Patent Publication Number: US-2021178398-A1

Title: Base module and tray insert of a multipurpose tray for an automated processing system, multipurpose tray for an automated processing system, and method of simplified loading/unloading of a multipurpose tray into/from an automated processing system

Description:
TECHNICAL FIELD 
     The present invention relates to a base module and a tray insert of a multipurpose tray for an automated processing system, such as an analytical, pre-analytical or post-analytical processing system, as well as to a multipurpose tray comprising such base module and such tray insert. The present invention further relates to a method of simplified loading/unloading of such a multipurpose tray into/from the automated processing system. In further detail, the present invention is directed to a base module of such a multipurpose tray, which base module receives the tray insert and forms the multipurpose tray together with the tray insert, wherein the tray insert can be particularly used for holding a plurality of reagent or sample tubes to be processed in the automated processing system. Based thereon, a method of simplified loading/unloading such a multipurpose tray into/from the automated processing system by an operator can also be achieved, as a side aspect of the present invention. 
     BACKGROUND 
     In laboratory settings, the processing of biological samples usually involves complex laboratory equipment and, thus, a complex workflow of operational steps carried out by laboratory personnel, such as a laboratory employee or a laboratory assistant, or the like. For example, such biological samples can entail human tissue, blood, saliva or urine, which samples are routinely taken from patients by medical personnel in hospitals or in private practice, for laboratory analysis, e.g. for determining concentration levels of different components within the taken samples. The complex workflow usually entails an increased number of procedural aspects to be considered ahead of the execution of each processing step, leading to a very time-consuming effort in addition to the processing steps themselves. Here, in order to counteract such time burden and comply with the usual time pressure of producing analysis results fast and reliable, any degree of automation of the largely manually carried-out process steps can significantly reduce personnel costs and increase sample throughput volume and, in turn, can reduce the time it takes to analyze the sample and report the results to the recipient. 
     Already available automated processing systems, e.g. for performing medical diagnostic analysis of biological samples, typically use already known commercially available sample containers for receiving the biological samples to be analyzed. Also, as addition to the biological samples, reagents can be required for the analysis, which reagents are usually provided in reagent containers. Such sample or reagent containers can come in the form of sample or reagent tubes, also referred to as primary tubes, or any other suitable kind of sample or reagent container which can be open at its top, or closed with a lid or the like, and which can differ slightly in shape and size. Furthermore, in order to facilitate the analysis process, it is common practice to use one particular kind of sample tube for a particular kind of sample, resulting in uniform sample containers for each type of sample, i.e. different kind of sample tubes for different kinds of sample, for the sake of streamlining the analyzing process and increasing sample throughput volume. The need to use different containers for different kinds of sample may also be dictated by various factors, such as sample volume, treatment conditions or the like, but -in any event- brings along the advantage that it is easier to tell different kinds of sample apart from each other, which makes it difficult to accidentally use the wrong kind of sample in a process intended for another kind of sample. This is particularly true where automated processing systems are used for processing the samples, since the automated systems usually comprise certain laboratory equipment designed for use with a certain kind of sample, i.e. with a certain kind of sample tube. 
     Now, in order to increase handling efficiency inside an automated processing system, such as an analytical, pre-analytical or post-analytical processing system, the sample or reagent tubes are usually placed into a tube tray adapted to support multiple tubes generally in an upright orientation. However, a laboratory usually receives the biological samples as well as the reagents in a lot of different tube types, wherein every tube type usually has its own tray adapted for the respective tube shape and size. This makes it complicated for an operator to load the laboratory processing system that treats different samples in different sample tube types. Also, in automated processing systems for processing biological samples, such as an analytical, pre-analytical or post-analytical processing system, the sample tubes are usually manipulated, for example by removing from or inserting into the tubes fluids or other specimen by means of a needle or pipette, or the like. Accordingly, handling the sample tubes generally requires a very exact positioning in relatively precise manner; otherwise, i.e. in case the sample tubes are not positioned with sufficient precision, a manipulator of such an automated processing system might not be in the position to reliably manipulate the sample tubes. Another problem of the trays is that their barcode is usually not human readable. Thus, the operator never knows if the samples are already treated, if they are fresh, or if the operator has to pay special attention, for example with infectious biological samples. A sample tube tray which can hold differently sized sample tubes and which is able to achieve the desired exact positioning can be gathered from, for example, U.S. Pat. No. 8,142,740 B2, in which a sample tube tray for an automated processing system is disclosed, which tray has several wells adapted to be able to hold one of two differently sized sample tubes in a concentric manner. As further known prior art, EP 2 098 296 A1 describes a sample tube tray for holding and positioning a plurality of sample tubes having outer diameters which lie within a predetermined diameter range. According to one particular embodiment of EP 2 098 296 A1, an improved sample tube tray is disclosed which can hold sample tubes with two different diameters, the tray basically consisting of uniformly spaced pillars. Accordingly, even though the known sample tube trays are usable for different sample tube designs, only fixed positions for the sample tubes can be used, i.e. it is not possible to merge smaller sample tubes closer together than bigger sample tubes. 
     Now, even though automated processing systems using the above described already known tube trays already improve sample processing efficiency by providing results more quickly while minimizing human error, there is the constant need for improvements in the overall performance of automated analyzer systems due to increasing demands on clinical laboratories regarding accuracy of analytical results and also sample throughput volume. In particular, the efficiency of patient sample handling continually needs to be increased, regardless of the assay to be performed. Here, the ability to quickly and securely introduce a plurality of samples or reagents into an automated processing system by means of sample or reagent tubes as described above is an important factor of achieving high efficiency in throughput of biological samples. In addition, the storing of different types of sample tubes or reagent tubes in one tray, the storing of several tube trays in small space, or the ability for laboratory personnel to carry several tube trays at once can highly increase the efficiency of patient sample handling with automated processing systems. Therefore, the constant need exists to improve the handling of a plurality of samples or reagents, of identical or mixed kind, in correlation with an automated processing system. 
     SUMMARY 
     The present invention addresses the above described problems and provides for a base module of a multipurpose tray, which base module receives at least one tray insert and forms the multipurpose tray together with the at least one tray insert, wherein the tray insert can be particularly used for holding a plurality of reagent or sample tubes to be processed in an automated processing system, such as an analytical, pre-analytical or post-analytical processing system. In particular, according to one aspect of the present invention, a base module of a multipurpose tray for such an automated processing system is provided, which base module is open on one side and comprises protrusions for engagement with at least one tray insert, wherein the at least one tray insert is releasably engagable within the open side of the base module by engagement with the protrusions of the base module. Accordingly, with the protrusions provided as integral part of the base module, at least one tray insert can be connected to the base module to form an engagement between the base module and the tray insert, or better between the open side of the base module and the tray insert, which engagement can be released again, if desired, in order to switch the tray insert with another tray insert of the same od a different kind, thereby rendering the tray to be a multipurpose tray. Accordingly, the multipurpose property of the multipurpose tray can already be achieved by the exchangeability of the tray insert, or also by the exchangeability of several tray inserts received by one and the same base module, for example in a mix and match manner, thereby achieving a high flexibility regarding the selection of tubes to be received by the multipurpose tray. Furthermore, as described further below in more detail, the multipurpose property of the multipurpose tray is also achieved by the ability of a tray insert according to the present invention to receive several different kinds of containers in one and the same tray insert, also referred to as universal tray insert. 
     According to a specific embodiment of the inventive base module of the presently described aspect, the protrusions of the base module, i.e. each protrusion provided integrally with the base module, protrudes laterally inward towards the inner side of the base module. Thereby, the protrusions of the base module can establish a form-fit connection in the form of a releasable push-in connection or a snap connection with respective counterparts of the tray insert, such as respective engagement features of the tray insert. For example, the protrusions of the base module can provide a kind of tongue of a tongue-and-groove connection, wherein respective engagement features of the tray insert provide the groove counterpart, for example by means of respective suitable engagement recesses. Here, for example, the protrusions can be of cylindrical shape, in order to match into respective circular engagement recesses in the tray insert. Alternatively or additionally, each cylindrical protrusion can comprise a center hole, open to the open side of the base module, which can receive a respective counterpart provided at the tray insert, such as a plug connector protruding from the bottom side of the tray insert, in order to be able to be pushed into the center hole of the respective protrusion of the base module, thereby establishing a push-in connection as mentioned above, which can be detached again. In general, regarding the manufacturing of a base module of the present invention, the base module can be an injection molded component, wherein the base module can be made of polypropylene (PP) or polycarbonate blends, such as polycarbonate with styrene acrylonitrile (PC/SAN) and polycarbonate with acrylonitrile-butadiene-styrene (PC/ABS), which all constitute injection-moldable materials. 
     According to a further specific embodiment of the inventive base module, the base module is stackable on top of another base module of a multipurpose tray of the same type. Thereby, several base modules can be stacked on top of each other in a space saving manner, independent from the tray insert provided in each of the stacked base modules, which also contributes to user convenience since several base modules can be stacked together when loaded with reagent or sample tubes provided by means of the respective tray insert and can be carried or transported in the stacked arrangement, thereby improving transportability and also storability of the base modules. In order to achieve such a stacking connection between at least two base modules on top of each other, the bottom side of each base module can comprise a step portion with reduced outer circumference, e.g. a narrowing step portion, which step portion matches into an upper edge of the open side of another base module. Accordingly, the step portion of the bottom side of the upper base module can be stacked into an upper edge of the open side of another base module, e.g. in a nestable manner. 
     Regarding the general structure of the inventive base module, the base module can comprise a rectangular structure with a substantially closed bottom side and at least partially closed side walls, usually four in number and thin-walled compared to the overall rectangular structure of the base module, wherein the upper side of the rectangular structure constitutes the above mentioned open side of the base module. With such structure, the base module constitutes a box shape with a substantially closed bottom, with the exception of manufacturing-related holes or slits or the like, side walls, which can be continuously closed or which can only be closed in part, and an open upper side, substantially without any kind of wall surface or the like. Regarding the structure of the side walls, at least one of the at least partially closed side walls of the base module can comprise an open side slot starting at the open upper side, i.e. the open upper side continues in the open side slot, and can continue toward the closed bottom side, wherein the side slot does not have to continue until the closed bottom side but can finish above the closed bottom, thereby constituting a window of the side wall open to the top. 
     According to an alternative specific embodiment, each side wall of the base module can comprise such an open side slot constituting a window of each side wall open to the top. Thereby, each corner of the rectangular structure comprises an angular corner post starting from the closed bottom and continuing to the open upper side, which angular corner posts can also be referred to as corner struts or corner pillars, achieving sufficient distance between the closed bottom side and the open side of the base module for receiving at least one tray insert as well as the tubes provided therein, without interacting with another base module stacked on top of it. 
     According to a further specific embodiment of the inventive base module, the base module comprises, as an interface, at least one handle on its outer circumference for improved transportability of the base module by an operator, such as laboratory personnel or the like, wherein the handle simplifies a grasping of the base module by the operator who can grasp the base module with one or two hands. Alternatively, the base module comprises, as an interface, two handles on its outer circumference opposite to each other, which even further improves the transportability of the base module by the operator, since the two opposite handles simplify a grasping of the base module by the operator who can grasp the base module with two hands. 
     According to a further specific embodiment of the inventive base module, the base module can comprise, as an interface, at least one engagement indentation on its outer circumference, wherein the engagement indentation is not to be confused by a handle as described above, but is particularly provided for a tray carrier, or tray carrier instrument such as a tray shuttle or the like, of the automated processing system, which carrier can engage with the indentation and, thus, pick up the base module, for improved transportability of the base module by the tray carrier in the course of an automated transportation process. For the sake of convenience, the at least one engagement indentation is provided within a handle positioned on the base module&#39;s outer circumference, as described above. Thereby, it becomes possible for the base module to be picked-up and transported not only by a human operator, but also by an automated tray carrier instrument, at the identical location at the base module. Similar to the provision of two handles as described above in an alternative embodiment, the base module can comprise, as an interface, two engagement indentations, or even more than two indentations, if necessary, on its outer circumference opposite to each other for improved transportability of the base module by the tray carrier of the automated processing system, wherein each engagement indentation can be provided within a handle allocated on the base module&#39;s outer circumference. Thereby, it becomes possible for the base module to be picked-up and transported not only by a human operator, but also by an automated tray carrier instrument in the same manner as being picked-up by a human operator with two hands, at the identical locations at the base module. The above described interfaces are provided as interfaces either form human interaction or as interface to instruments of an automated processing system, wherein the interfaces can be provided for interaction with such an instrument for the transport to and from loading slots of the automated processing system, to a work deck of the automated processing system, to a barcode labeler of the automated processing system, or for a tray shuttle provided within of the automated processing system. 
     According to a further specific embodiment of the inventive base module, the base module can comprise at least one color indicator for indication of a loading status of a content of the multipurpose tray, i.e. a content of the tray insert as received in the base module of the multipurpose tray. As one example, the color indicator can provide four different colors, which can indicate that the multipurpose tray has new, i.e. unprocessed, content, already processed content, content designated for the archive, or erroneous content, wherein the unprocessed content can be color-coded with green color and the already processed content, or alternatively erroneous content, can be color-coded with red color. Here, as a specific embodiment, the color indicator can be operable manually by the operator, and/or can be implemented in the form of a rotating indicator plug or pole provided in a respective pocket in the base module, for example in one of several corner posts of the base module, wherein the pocket comprises a viewing window to the outside, in which the respective color can be shown and changed by rotation of the indicator pole. Also, in case that the multipurpose tray carries content that is not in need of loading status indication, for example in case the tray insert carries consumable tips or the like, i.e. content without any status, a so-called blind plug can be fitted into the base module pocket, i.e. a plug without any different colors provided on it, such as a grey-colored plug or the like. Accordingly, the color indicator can be replaced, if desired, for improved user convenience. Furthermore, it is to be noted that the color indicator is particularly reasonable when using a so-called universal tray insert which can hold different kinds of sample tubes, or when using a urine sample container tray. On the other hand, a blind plug can be reasonable when using a consumable tips carrying tray insert, as mentioned before. As additional aspect of the provision of the indicator in form of an indicator pole stuck into a pocket of the base module, any optical sensor of the automated processing system can be used to identify the correct loading of the multipurpose tray into a loading slot of the automated processing system, since the pocket is either provided on the end of the tray loaded first into the loading slot, or not. Depending on the desired orientation of the tray when loaded into the loading slot, the correct orientation or a false orientation can be detected and, for example, signalized to an operator. 
     According to a further specific embodiment of the inventive base module, the base module can comprise at least one writable surface on its outer circumference, in order for an operator to provide the base module with a human readable marking and allowing rapid marking and erasing of such markings on the surface by a human operator, if desired, wherein the writable surface can be implemented by means of a whiteboard material, i.e. a wipeable material, to be able to use it more then one time. Thereby, any operator can provide the base module, and, thus, the multipurpose tray with human-readable markings, if desired, which can easily be erased again, for example when using the base module another time together with another tray insert, in order to write the content of the tray insert onto the base module. According to a one implementation of the writable surface, the same can be provided by means of the placement of a label on a side wall of the base module, for example the right side of the base module, wherein it is useful if the writable surface in the form of the label can only be cleaned with alcohol or suchlike, in order to improve the durability of the operator&#39;s markings. Thus, the writable surface provides white space to label the trays with notes for co-workers or co-operators, or the like, for example in order to prevent risk of loosing of delayed samples. 
     In addition to the human-readable marking as described before, the base module of the present invention can also comprise at least one identification code on its outer circumference, which can be an adhesive label or the like, carrying a human-readable machine-writing, which can provide substantial information about the base module or its content for a human operator. Alternatively or additionally, a machine-readable identification code can be provided on the outer circumference of the base module, for example implemented by a barcode or the like, or also in the form of a RFID tag or the like, which makes an automatic identification of the base module or its content in the automated processing system possible, and which can provide a unique identification code for each base module. For example, such barcode or RFID tag can consist of 3 characters for identification of the tray type, i.e. the type of tray insert provided in the base module, and 5 characters giving a consecutive serial number, for recordability reasons. 
     According to another aspect of the present invention, and in complementary addition to the base module as described above, a tray insert of a multipurpose tray for an automated processing system is provided herewith, for holding a plurality of reagent or sample tubes having similar or differing diameters, wherein the tray insert can also be referred to as universal tray insert or universally applicable tray insert and comprises an array of tube receiving recesses with different sizes, thereby achieving the universal property of the universal tray insert, wherein the size can be, for example, the tube receiving recess diameter, and tube receiving recesses can be formed in a substantial cylindrical shape. In general, regarding the manufacturing of such a tray insert of the present invention, the tray insert can be an injection molded component, wherein the tray insert can be made of polypropylene (PP) or polycarbonate blends, such as polycarbonate with styrene acrylonitrile (PC/SAN) and polycarbonate with acrylonitrile-butadiene-styrene (PC/ABS), which all constitute injection-moldable materials. Regarding the structure of the universal tray insert of the present invention, the above mentioned array of tube receiving recesses comprises at least a first group of tube receiving recesses, and also a second group of tube receiving recesses, wherein the size of a recess of the first group of tube receiving recesses and the size of a recess of the second group of tube receiving recesses differ from each other, i.e. the recess sizes between those groups are different to each other. For example, the first group of tube receiving recesses can be used for receiving a first group of tubes with a large diameter, and the second group of tube receiving recesses can be used for receiving tubes with a smaller diameter than the first group of tubes. Moreover, a contour of an inner circumference of each tube receiving recess of the first group of tube receiving recesses intersects with a contour of an inner circumference of at least one adjacent tube receiving recess of the second group of tube receiving recesses. Here, as contour of an inner circumference of a tube receiving recess, an outline of the inner circumference of the tube receiving recess is to be understood, wherein the contour or outline of the inner circumference of the tube receiving recess can also be identified as the substantial cross-section of the tube receiving recess when viewed from above. However, the inner circumferences of the tube receiving recesses of both the first group and the second group do not have to be continuous, wherein the tube receiving recesses of both groups can intersect with each other when viewed from above, thus exhibiting an intersection of the contour of an inner circumference of each tube receiving recess of the first group of tube receiving recesses with the contour of an inner circumference of at least one adjacent tube receiving recess of the second group of tube receiving recesses. With such a particular structure of tube receiving recesses with differing sizes, a universal tray insert design can be achieved which can receive different container shapes and sizes, wherein it particularly becomes possible to merge smaller containers closer together than bigger containers. Accordingly, different tube types with differing diameters can fit in the universal tray insert and, thus, in the respective multipurpose tray, always in an optimized way, in order to achieve an increase in receivable tube number that can be inserted into the universal tray insert. Thus, such a particular structure of tube receiving recesses results in the universal property of the universal tray insert, since the tray insert can be universally used for a plurality of different kinds of sample tubes. Here, as an example, in case only one type of tubes is loaded into the universal tray insert, it becomes possible to load about 20 pieces, such as 21 pieces of tubes with large diameter, such as PreservCyt tubes, or about 30 pieces, such as 32 pieces of tubes with a smaller diameter, such as SurePath tubes. In case different tubes are loaded, of the previously described kind, between about 20 and 30 pieces can be loaded in a mixed manner. 
     According to a further specific embodiment of the inventive tray insert, the intersection of contours of the first group of tube receiving recesses and the second group of tube receiving recesses corresponds to a non-tangential crossover of contours. This is to be understood in that the intersection point or junction point between the different contours, i.e. the contour of an inner circumference of each tube receiving recess of the first group of tube receiving recesses crosses the contour of an inner circumference of at least one adjacent tube receiving recess of the second group of tube receiving recesses in a non-tangential manner. This is particularly relevant when considering the cylindrical contours of each tube receiving recess, since such an arrangement specifically assists in achieving the optimized way of fitting tubes with differing diameters into the inventive tray insert, in order to achieve an increase in receivable tube number that can be inserted into the tray insert. Alternatively or additionally, a center axis of each respective tube receiving recess of the first group of tube receiving recesses can be arranged in an eccentric manner in relation to a center axis of an adjacent tube receiving recess of the second group of tube receiving recesses, meaning that the center axes of both groups of tube receiving recesses do not coincide with each other, which additionally assists in achieving the already described optimized way of fitting tubes with differing diameters into the inventive tray insert. Here, the distances between the respective axes are chosen so that a “wrong” loading of tubes into the universal tray insert is not possible, or at least can easily be detected by the operator during loading. 
     According to a further specific embodiment of the inventive tray insert, a depth of each tube receiving recess of the first group of tube receiving recesses is different from a depth of each tube receiving recess of the second group of tube receiving recesses. Thereby, tubes with differing length can also be received by the presently described tray insert, wherein it can be advantageous that the depth of the different groups of tube receiving recesses are chosen such that the tops of the one group of tubes having a longer length do not or only slightly protrude compared to the other group of tubes having a shorter length. 
     According to a further specific embodiment of the inventive tray insert, the array of tube receiving recesses comprises a third group of tube receiving recesses additionally to the already described first and second groups of tube receiving recesses, wherein a contour of an inner circumference of at least one of tube receiving recesses of the third group of tube receiving recesses intersects with a contour of an inner circumference of at least one adjacent tube receiving recess of the first and/or second group of tube receiving recesses. Accordingly, the array of tube receiving recesses comprises additionally a third group of tube receiving recesses, wherein the size of a recess of the third group of tube receiving recesses and the size of a recess of the first and/or second group of tube receiving recesses differ from each other, i.e. the recess sizes between those groups are different to each other. For example, the first group of tube receiving recesses can be used for receiving a first group of tubes with a large diameter, the second group of tube receiving recesses can be used for receiving tubes with a smaller diameter than the first group of tubes, and the third group of tube receiving recesses can be used for receiving a third group of tubed with an even smaller diameter than the second group of tubes. Moreover, a contour of an inner circumference of at least one of a of tube receiving recess of the third group of tube receiving recesses intersects with a contour of an inner circumference of at least one adjacent tube receiving recess of the first/second group of tube receiving recesses. Here again, as contour of an inner circumference of a tube receiving recess, an outline of the inner circumference of the tube receiving recess is to be understood, wherein the contour or outline of the inner circumference of the tube receiving recess can also be identified as the substantial cross-section of the tube receiving recess when viewed from above. However, the inner circumferences of the tube receiving recesses of all three groups do not have to be continuous, wherein the tube receiving recesses of all groups can intersect with each other when viewed from above, thus exhibiting an intersection of the contour of an inner circumference of each tube receiving recess of the first group of tube receiving recesses with the contour of an inner circumference of at least one adjacent tube receiving recess of the second group of tube receiving recesses and/or with the contour of an inner circumference of at least one adjacent tube receiving recess of the third group of tube receiving recesses. With such a particular structure of tube receiving recesses with differing sizes, the above mentioned universal tray insert design can be further improved in that it can receive three different container shapes or sizes, wherein it again becomes possible to merge smaller containers closer together than bigger containers. Accordingly, different tube types with three differing diameters can fit in the universal tray insert and, thus, in the respective multipurpose tray, always in an optimized way, in order to achieve an increase in receivable tube number that can be inserted into the universal tray insert. For example, in case only one type of tubes is loaded into the universal tray insert, it becomes possible to load about 20 pieces, such as 21 pieces of tubes with large diameter, such as PreservCyt tubes, about 30 pieces, such as 32 pieces of tubes with a smaller diameter, such as SurePath tubes, or about 80 pieces, such as 78 pieces of tubes with an even smaller diameter, such as PCR tubes. Thus, the array of tube receiving recesses can receive between about 20 and 80 sample tubes, of the same type or of different types in a mixed manner, depending on the respective diameter of the sample tubes and, thus, depending on the diameters of the tube receiving recesses. With an alternative arrangement of tube receiving recesses, 20 pieces of tubes with large diameter, such as PreservCyt tubes, 20 pieces of tubes with a smaller diameter, such as SurePath tubes, or 62 pieces of tubes with an even smaller diameter, such as PCR tubes can be loaded. Such a particular structure of tube receiving recesses results in further improvement of the universal property of the universal tray insert, since the tray insert can be universally used for an even bigger plurality of different kinds of sample tubes. As an additional optional feature, in order to achieve a further stabilized holding of any kind of sample tube, which makes it possible to also introduce smaller tubes into larger tube receiving recesses, a centering spring can be provided inside at least one of the tube receiving recesses, for centering a tube inside the respective tube receiving recess, i.e. for centering and holding a smaller tube inside a larger tube receiving recess. Accordingly, such a centering spring can further improve the universal property of the universal tray insert, since the tray insert can be universally used for an ever-greater plurality of different kinds of sample tubes. For example, a centering spring in accordance with the present invention can comprise a substantially circular middle part for attachment inside a tube receiving recess, and several clamp arms protruding away from the middle part in a longitudinal manner, each comprising an inwardly protruding nib at its end, for contacting the tube to be held, thereby holding and centering the same in coaxial manner with the centering spring, i.e. with the respective tube receiving recess, in a clamped manner. Such centering spring, as a separate component of the tray insert, can be made of spring steel, in order to improve its clampability, in addition to the clampability as achieved by the shape of the centering spring itself. 
     According to a further specific embodiment of the inventive tray insert, a center axis of each respective tube receiving recess of the third group of tube receiving recesses is arranged in an eccentric manner in relation to a center axis of an adjacent tube receiving recess of the first and/or second group of tube receiving recesses, meaning that the center axes of all groups of tube receiving recesses do not coincide with each other, which additionally assists in achieving the already described optimized way of fitting tubes with differing diameters into the inventive tray insert. Here, the distances between the respective axes are chosen so that a “wrong” loading of tubes into the universal tray insert is not possible, or at least can easily be detected by the operator during loading. Alternatively or additionally, a depth of each tube receiving recess of the third group of tube receiving recesses is different from a depth of each tube receiving recess of the first and/or second group of tube receiving recesses. Thereby, tubes with differing length can also be received by the presently described tray insert, wherein it can be advantageous that the depth of the different groups of tube receiving recesses are chosen such that the tops of one or two groups of tubes having a longer length do not or only slightly protrude compared to the remaining group of tubes having a shorter length. Moreover, a contour of each tube receiving recess of one group of tube receiving recesses can be spaced apart from a contour of an adjacent tube receiving recess of the same group of tube receiving recesses. Thus, a direct contact between the tubes of the same group of tubes can be avoided, thereby achieving a maximum exploitation of the space provided by the entire tray insert for this kind of tube. 
     According to a further specific embodiment of the inventive tray insert, fiducial markers are provided at the edge of an upper surface of the tray insert. The fiducial markers are used for clear allocation of each of the tube receiving recesses in the tray insert, wherein the fiducial markers can be provided in the form of a grid consisting of alphabetic characters and/or numbers, for identifying each tube receiving recess. Here, as an example, the individual positions can be printed on the edge of the tray insert in the form of a grid, such as known from a chessboard, wherein letters can assign rows and numbers can assign columns, for example from A1 to M11. 
     As already mentioned above, the tray insert comprises engagement features for being releasably engagable with protrusions within an open side of a base module of a multipurpose tray. As already described above in relation to the base module, the protrusions of the base module can provide a kind of tongue of a tongue-and-groove connection, wherein the respective engagement features of the tray insert provide the groove counterpart, for example by means of respective suitable engagement recesses which can be provided in an outer circumferential edge of the tray insert. Alternatively, the engagement features can be provided in the form of plug-in connectors provided on a bottom side of the tray insert, which connectors can be pushed into a center hole of the respective protrusions of the base module. In both cases, a push-in connection between the base module and the tray inset can be achieved, which can be detached again. 
     According to another aspect of the present invention, a multipurpose tray for an automated processing system is also provided by the present invention, which multipurpose tray comprises a base module as described above in detail, as well as at least one tray insert as described above in detail. Here, the tray insert can be enclosed at least in part by the base module in a framed manner without the at least one tray insert protruding to the outside of the base module. Also, as described above, the content of the tray insert does not protrude to the outside of the base module. Thereby, the stackability of the multipurpose tray can be achieved, independent the chosen tray insert and its content. Further, the protrusions of the base module and the engagement features of the tray insert establish a form-fit connection in the form of a releasable push-in connection or a snap connection, as already described above in detail. 
     Furthermore, in accordance with a further aspect of the present invention, a method of simplified loading/unloading of a multipurpose tray into/from an automated processing system by an operator is also provided. Such multipurpose tray can be the multipurpose tray as described above, or, alternatively, a multipurpose tray having any kind of tray insert inserted therein. Here, the inventive method comprises the steps of loading such a multipurpose tray into a loading slot, also referred to as input slot, of the automated processing system, wherein the automated processing system can comprise more than one loading slot; processing the content of the multipurpose tray by laboratory instrument of the automated processing system, such as an analytical instrument; and unloading the multipurpose tray from an unloading slot, also referred to as output slot, of the automated processing system, wherein the automated processing system can comprise more than one unloading slot. Here, the automated processing system comprises a sensor recognizing the content of the multipurpose tray loaded into the loading slot without interaction between the operator and software of the automated processing system, i.e. the automated processing system is able to automatically recognize the loaded multipurpose tray and its content by means of the sensor, such as an optical sensor, an RFID sensor or the like, and, thus, is able to identify the necessary or desired processing steps to be carried out automatically by the laboratory instruments inside the automated processing system, without the necessity for the operator of data input regarding the content of the multipurpose tray, for example by means of a user interface. Moreover, the multipurpose tray to be unloaded from the unloading slot of the automated processing system can be unloaded by the operator from the unloading slot without interaction between the operator and software of the automated processing system regarding the format or content of the multipurpose tray, i.e. the automated processing system allows unloading of the multipurpose tray without the necessity for the automated processing system to provide data about the multipurpose tray to be unloaded to the operator, for example by means of the user interface. However, in general, any multipurpose tray to be unloaded from the unloading slot of the automated processing system can only be unloaded by the operator from the unloading slot by interaction between the operator and software of the automated processing system, i.e. the automated processing system allows unloading of the multipurpose tray only with a respective input from the operator to the system, for example by means of the user interface. In general, the automated processing system can comprise a control unit carrying application software for interaction with an operator as well as for controlling the workflow inside the automated processing system. 
     The presently described method is based on the fact that it is so far only known in the art that loading slots of an automated processing system can only be used by particularly identifying the respective slot for loading a tray that carries sample tubes, or a loading slot for loading a tray that carries disposables/consumables like pipette tips. Accordingly, only the loading of samples and reagents in different randomized slots is well known, but not the combination of loading sample tubes containing a liquid and racks or carriers that only contain consumables/disposables like pipette tips in a simple way. Accordingly, the presently described inventive method offers a user-convenient way of loading samples and disposables into an automated processing system. The necessity of such improvement is based on the fact that the operator in a laboratory usually has to load a lot of different trays with supplies, consumables and samples into the loading slots of the automated processing system. Each of these trays has usually a different format and, thus, a different loading slot which is adapted to the format of the tray. However, with a multipurpose tray as described, each tray can have the same format for different samples and supplies. Accordingly, the operator can load the trays comprising supplies and/or samples into one or several random loading slots, without having to identify the matching loading slot each time a tray has to be loaded into the automated processing system. 
     As an example of the presently described inventive method, the automated processing system can be equipped with, e.g., 8 slots as tray interface between the outside and the inside of the automated processing system, wherein 4 of the slots can be assigned to be loading slots and the remaining 4 slots can be assigned to be unloading slots, for user convenience. For example, in an arrangement with two rows of slots, 4 slots on top arranged of the other 4 slots, the top 4 slots can be assigned to be the tray loading slots, and the bottom 4 slots can be assigned to be the tray unloading slots. Alternatively, all slots can be used for loading and unloading at the same time. Now, regarding the loading step of the presently described method, the multipurpose tray is loaded into any of the slots assigned to be a loading slot of the automated processing system, wherein the multipurpose tray can carry one or several universal tray inserts, one or several urine container tray inserts, and/or one or several tip rack tray inserts. Accordingly, as specific embodiment of the inventive method, the operator can fill sample or reagent tubes, or disposables, such as pipette tips, into the multipurpose tray as its content, wherein the step of loading the filled multipurpose tray into the loading slot or any loading slot of the automated processing system is carried out without the necessity of exchange of data regarding the format or content of the multipurpose tray with the software of the automated processing system. Due to the automatic recognition of the loaded tray by the automated processing system, the trays are loadable by the operator into the loading slots without the necessity of any user interaction with the software of the automated processing system, for example by means of a user interface or the like. 
     According to a further specific embodiment of the inventive method, the step of loading the multipurpose tray comprises loading a multipurpose tray with prioritized content into a predetermined loading slot of a plurality of loading slots, wherein the automated processing system carries out the processing step with prioritizing the multipurpose tray with prioritized content. Further, the predetermined loading slot can be a priority loading slot, and the prioritized content can be prioritized sample. For example, one of the 4 loading slots of the above described example can be designated to be the priority loading slot for prioritized trays, i.e. trays with prioritized content, such as prioritized samples that should be processed immediately, without getting in line behind other, non-prioritized samples. Thereby, the order of automated steps of processing sample can be influenced by the operator in this regard, if desired. 
     As further specific embodiment of the inventive method, the automated processing system can lock an unloading slot for preventing unloading of the multipurpose tray from the unloading slot before clearance, while the respective multipurpose tray is in processing. Accordingly, while each tray is in processing, the automated processing system prevents manual removal of the tray from the respective slot. Such prevention can be achieved by a manual lock or the like, holding the respective tray in the respective slot in place. Alternatively, or additionally, the automated processing system can comprise a loading/unloading status indicator for each slot, indicating the status of loading/unloading permission or loading/unloading prohibition for each slot. Thereby, in case the tray is not supposed to be unloaded, for example since processing of its content is still in process, the status indicator can signal the operator an unloading prohibition signal, for example in the form of a red light provided near the respective slot. 
     Regarding the unloading step of the present inventive method, it can be established that different kinds of tray with differing contents can be unloaded from the unloading slots. However, as a specific embodiment of the presently described method, one of the unloading slots can be designated to be an unloading slot for unloading sample error trays, i.e. trays with sample tubes that have been identified by the automated processing system to exhibit some kind of error, such as an unreadable label or the like, or also in case of an erroneous sample. Accordingly, the step of unloading the multipurpose tray can comprise unloading of a multipurpose tray with predetermined content from a predetermined unloading slot, wherein the predetermined content can be containers with erroneous samples. 
     The present invention is not limited to the particular methodology described herein because they may vary. Although any devices, methods and materials similar or equivalent to those described herein can be used in the practice of the present invention, the specific devices, specific methods and specific materials are described herein. Further, the terminology used herein is for the purpose of describing specific embodiments only and is not intended to limit the scope of the present invention. 
     In the context of the present invention, the term “automated processing system” as used herein refers to an automated laboratory system in a laboratory comprising one or more laboratory instrument(s) operatively connected to a control unit, such as an analytical, pre-analytical or post-analytical processing system, for automatically processing biological sample. In general, before a chemical, biological, physical, optical or other technical analysis can be performed on a sample by an analytical processing system, a variety of different pre-analytical processing steps may have to be executed on a sample of a patient by instruments of a pre-analytical processing system, such as sample centrifugation instrument for centrifuging a sample, sample resuspension instrument for resuspension of a sample, sample container capping or decapping instruments for capping and/or decapping a sample container, a recapping instrument for recapping a sample container after decapping the same, and/or aliquotation instrument for dividing a sample into aliquots of the sample, and the like. After the analysis, a variety of different pre-analytical processing steps may have to be executed on the sample by instruments of a post-analytical processing system, for example for executing one or more post-analytical processing steps on one or more biological samples, such as the verification and review of the analytical results, as well as the communication of these results to the operator of the laboratory system and their interpretation. 
     The term “laboratory instrument” or “instrument” of the laboratory as used herein encompasses any apparatus or apparatus component operable to execute one or more processing steps/workflow steps on one or more biological samples. The expression “processing steps” thereby refers to physically executed processing steps such as centrifugation, aliquotation, sample analysis and the like. The term “laboratory instrument” or “instrument” of the laboratory covers pre-analytical instruments, post-analytical instruments and also analytical instruments. 
     The term “pre-analytical” as used herein relates to the execution of one or more pre-analytical processing steps on one or more biological samples, thereby preparing the samples for one or more succeeding analytical tests. A pre-analytical processing step can be, for example, a centrifugation step, a capping-, decapping- or recapping step, an aliquotation step, a step of adding buffers to a sample and the like. The term “analytical” as used herein encompasses any process step carried out by one or more laboratory devices or operative units which are operable to execute an analytical test on one or more biological samples. The term “post-analytical” as used herein relates to the execution of one or more post-analytical processing steps on one or more biological samples, which steps begin with the verification and review of the analytical results, as well as to the communication of these results to the operator of the laboratory system and their interpretation. 
     The term “control unit” as used herein encompasses any physical or virtual processing device configurable to control a laboratory system comprising one or more laboratory instruments in a way that workflow(s) and workflow step(s) are conducted by the laboratory system. The control unit may, for example, carry different kinds of application software and instruct the laboratory system (or a specific instrument thereof) to conduct pre-analytical, post analytical and analytical workflow(s)/ workflow step(s). The control unit may receive information from a data management unit regarding which steps need to be performed with a certain sample. Further, the control unit might be integral with a data management unit, may be comprised by a server computer and/or be part of one instrument or even distributed across multiple instruments of the laboratory system. The control unit may, for instance, be embodied as a programmable logic controller running a computer-readable program provided with instructions to perform operations. 
     The term “user interface” as used herein encompasses any suitable piece of application software and/or hardware for interactions between an operator and a machine, including but not limited to a graphical user interface for receiving as input a command from an operator and also to provide feedback and convey information thereto. Also, a system/device may expose several user interfaces to serve different kinds of users/operators. 
     In the context of biomedical research, analytical processing is a technical procedure to characterize the parameters of a biological sample or of an analyte. Such characterization of parameter comprises, for example, the determination of the concentration of particular proteins, metabolites, ions or molecules of various sizes in biological samples derived from humans or laboratory animals, or the like. The gathered information can be used to evaluate e.g. the impact of the administration of drugs on the organism or on particular tissues. Further analyses may determine optical, electrochemical or other parameters of the samples or the analytes comprised in a sample. 
     In the context of the present invention, an erroneous sample and/or an erroneous sample container will be determined as being not in the condition to be processed, i.e. not in the condition to be completed successfully, if an error occurred during the sample processing workflow and if the laboratory system was not able to continue the workflow run until its completion, which resulted in an undesired workflow run interruption. 
     The term “workflow” as used herein encompasses any task that comprises a number of steps, such as for maintenance or operation of the system or one of its system components. 
     The term “workflow step” as used herein encompasses any activity belonging to a workflow. The activity can be of an elementary or complex nature and is typically performed at or by one or more instrument(s). 
     The terms “sample” and “biological sample” refer to material(s) that may potentially contain an analyte of interest. The sample can be derived from any biological source, such as a physiological fluid, including blood, saliva, ocular lens fluid, cerebrospinal fluid, sweat, urine, stool, semen, milk, ascites fluid, mucous, synovial fluid, peritoneal fluid, amniotic fluid, tissue, cultured cells, or the like. The patient sample can be pretreated prior to use, such as preparing plasma from blood, diluting viscous fluids, lysis or the like. Methods of treatment can involve filtration, distillation, concentration, inactivation of interfering components, and the addition of reagents. A sample may be used directly as obtained from the source or used following a pretreatment to modify the character of the sample. In some embodiments, an initially solid or semi-solid biological material can be rendered liquid by dissolving or suspending it with a suitable liquid medium. In some embodiments, the sample can be suspected to contain a certain antigen or nucleic acid. 
     The term “sample tube” or “sample container” refers to any individual container for transporting, storing and/or processing a sample. In particular, the term without limitation refers to a piece of laboratory glass- or plastic-ware optionally comprising a cap on its upper end. Sample tubes, e.g. sample tubes used to collect blood, often comprise additional substances such as clot activators or anticoagulant substances which have an impact on the processing of the sample. As a consequence, different tube types typically are adapted for pre-analytical, analytical and/or post-analytical requirements of a particular analysis, e.g. a clinical chemistry analysis, a hematological analysis or a coagulation analysis. A mix-up of sample tube types can make (blood) samples unusable for analysis. To prevent errors in the collection and handling of samples, the sample caps of many tube manufacturers can be encoded according to a fixed and uniform color scheme. Some sample tubes types in addition or alternatively are characterized by particular tube dimensions, cap dimensions, and/or tube color. A dimension of a tube comprises e.g. its height, its size and/or further characteristic shape properties. 
     As used herein and in the appended claims, the singular forms “a”, “an”, and “the” include plural reference unless the context clearly dictates otherwise. Similarly, the words “comprise”, “contain” and “encompass” are to be interpreted inclusively rather than exclusively; that is to say, in the sense of “including, but not limited to”. Similarly, the word “or” is intended to include “and” unless the context clearly indicates otherwise. The terms “plurality”, “multiple” or “multitude” refer to two or more, i.e. 2 or &gt;2, with integer multiples, wherein the terms “single” or “sole” refer to one, i.e. =1. Furthermore, the term “at least one” is to be understood as one or more, i.e. 1 or &gt;1, also with integer multiples. Accordingly, words using the singular or plural number also include the plural and singular number, respectively. Additionally, the words “herein,” “above,” and “below” and words of similar import, when used in this application, shall refer to this application as a whole and not to any particular portions of the application. 
     The description of specific embodiments of the disclosure is not intended to be exhaustive or to limit the disclosure to the precise form disclosed. While the specific embodiments of, and examples for, the disclosure are described herein for illustrative purposes, various equivalent modifications are possible within the scope of the disclosure, as those skilled in the relevant art will recognize. Specific elements of any foregoing embodiments can be combined or substituted for elements in other embodiments. Furthermore, while advantages associated with certain embodiments of the disclosure have been described in the context of these embodiments, other embodiments may also exhibit such advantages, and not all embodiments need necessarily exhibit such advantages to fall within the scope of the disclosure. 
     The following examples are intended to illustrate various specific embodiments of the present invention. As such, the specific modifications as discussed hereinafter are not to be construed as limitations on the scope of the present invention. It will be apparent to the person skilled in the art that various equivalents, changes, and modifications may be made without departing from the scope of the present invention, and it is thus to be understood that such equivalent embodiments are to be included herein. Further aspects and advantages of the present invention will become apparent from the following description of particular embodiments illustrated in the figures. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a schematic perspective illustration of several multipurpose trays according to an embodiment of the present invention, consisting of a base module and different tray inserts inserted therein, respectively, arranged next to each other for direct comparison; 
         FIG. 2  is a schematic perspective illustration of a base module of any one of the multipurpose trays as shown in  FIG. 1 ; 
         FIGS. 3 and 4  are schematic perspective illustrations of a multipurpose tray with a base module as shown in  FIG. 1  and an empty universal tray insert inserted therein, viewed from different angles, as also shown in  FIG. 1  on the left side, wherein  FIG. 3  comprises an enlarged detail of the inner structure of a handle of the base module in a longitudinal cross section along line A-A; 
         FIG. 5  is a schematic perspective illustration of two multipurpose trays, each with a base module as shown in  FIG. 1  and an empty universal tray insert inserted therein, stacked on top of each other; 
         FIG. 6  is an enlarged detail of a top view of a left side of the multipurpose tray as shown in  FIGS. 3 and 4 ; 
         FIG. 7  is a schematic perspective illustration of a multipurpose tray with a universal tray insert inserted therein, and with different kinds of containers mixedly arranged therein next to each other in an optimized manner; 
         FIG. 8  is an enlarged detail view of the left side of the multipurpose tray as shown in  FIG. 7 ; 
         FIG. 9  is a schematic perspective illustration of the multipurpose tray as shown in  FIG. 7 , viewed from a different angle; 
         FIG. 10  is a top view of the multipurpose tray as shown in  FIGS. 7 to 9 ; 
         FIG. 11  is a schematic perspective illustration of a multipurpose tray with a universal tray insert inserted therein, fully filled with containers of one and the same kind, comprising a large diameter, and arranged therein next to each other in an optimized manner; 
         FIG. 12  is a top view of the multipurpose tray as shown in  FIG. 11 ; 
         FIG. 13  is a schematic perspective illustration of a multipurpose tray with a universal tray insert inserted therein, fully filled with containers of one and the same kind, comprising a mid-sized diameter, and arranged therein next to each other in an optimized manner; 
         FIG. 14  is a top view of the multipurpose tray as shown in  FIG. 13 ; 
         FIG. 15  is a schematic perspective illustration of a multipurpose tray with a universal tray insert inserted therein, fully filled with containers of one and the same kind, comprising a small diameter, and arranged therein next to each other in an optimized manner; 
         FIG. 16  is a top view of the multipurpose tray as shown in  FIG. 15 ; 
         FIG. 17  is a top view of a an alternative embodiment of a multipurpose tray as shown in  FIGS. 3 and 4 ; 
         FIG. 18  is a schematic perspective illustration of a multipurpose tray with a tray insert for urine sample containers inserted therein, as also shown in  FIG. 1  in the middle position; 
         FIG. 19  is a schematic perspective illustration of two multipurpose trays as shown in  FIG. 18 , stacked on top of each other, each with one single urine sample container provided therein; 
         FIG. 20  is a schematic perspective illustration of a multipurpose tray with several tray inserts inserted therein, each tray insert consisting of a tip rack for receiving consumable pipette tips, as also shown in  FIG. 1  on the right side; 
         FIG. 21  is an enlarged schematic perspective illustration of a centering spring for a universal tray insert according to an embodiment of the present invention; 
         FIG. 22  is a flowchart illustrating an embodiment of a method of the present invention; 
         FIG. 23  is a schematic perspective illustration of a loading/unloading station of an automated processing system, for loading/unloading one or several multipurpose trays according to an embodiment of the present invention; and 
         FIG. 24  is a schematic illustration of the arrangement of loading/unloading slots as shown in  FIG. 23 . 
     
    
    
     LIST OF REFERENCE NUMERALS 
       10  loading/unloading station 
       11  flap door 
       12  loading slot 
       121  prioritized loading slot 
       13  unloading slot 
       131  error-out unloading slot 
       20  multipurpose tray for different sample tubes 
       20 ′ alternative multipurpose tray for different sample tubes 
       30  multipurpose tray for urine sample containers 
       40  multipurpose tray for disposable pipette tips 
       100  base module 
       101  closed bottom 
       102  side plate 
       103  side slot/window 
       104  corner post 
       1041  corner post window 
       1042  top indentation 
       105  step portion 
       106  handle 
       1061  engagement indentation 
       107  color indicator 
       1071  rotary knob 
       108  writable surface 
       109  identification code 
       110  engagement protrusion 
       200  universal tray insert 
       201  large diameter tube receiving recess 
       201 ′ large diameter tube receiving recess 
       2011  large diameter tube receiving recess center axis 
       202  middle diameter tube receiving recess 
       202 ′ middle diameter tube receiving recess 
       2021  middle diameter tube receiving recess center axis 
       203  small diameter tube receiving recess 
       203 ′ small diameter tube receiving recess 
       2031  small diameter tube receiving recess center axis 
       204  bracket 
       204 ′ recess division bridge/bar 
       205 ′ tube spring 
       210  engagement recess 
       220  fiducial markers 
       220 ′ fiducial markers 
       230  color indicator groove 
       300  urine sample tray insert 
       301  urine sample container recess 
       400  tip rack tray insert 
       401  pipette tip hole 
       410  pipette tip rack 
       420  plug connector 
       501  large diameter sample tube 
       502  middle diameter sample tube 
       503  small diameter sample tube 
       601  urine sample container 
       701  pipette tip 
       800  centering spring 
       810  centering spring middle part 
       820  clamp arm 
       830  nib 
       831  pointed nib end 
       910  Decision step 
       920  Execution step 
       930  Execution step 
       940  Execution step 
       950  Execution step 
     DETAILED DESCRIPTION 
     In  FIG. 1 , three different variations of a multipurpose tray according to an embodiment of the present invention are shown as schematic perspective illustrations arranged next to each other. According to the choice of tray insert, the purpose of the multipurpose tray can change. In particular, on the left side of  FIG. 1 , a multipurpose tray  20  with a base module  100  as shown in  FIG. 2  and an empty universal tray insert  200  inserted therein is shown, without any sample tubes arranged in the universal tray insert  200 . Further, in the middle position of  FIG. 1 , a multipurpose tray  30  with a base module  100  as shown in  FIG. 2  and a urine sample tray insert  300  for urine sample containers inserted therein is shown, without any urine sample containers arranged in the urine sample tray insert  300 . Moreover, on the right side of  FIG. 1 , a multipurpose tray  40  with a base module  100  as shown in  FIG. 2  and a tip rack tray insert  400  with four tip racks inserted therein is shown, without any consumable pipette tips arranged in the tip rack tray insert  400 . In the following, each of the multipurpose trays  20 ,  30 ,  40  and its particular structure is described in more detail based on respective illustrations in the drawings. 
     As general basis for each multipurpose tray  20 ,  30 ,  40 , the base module  100  as shown in  FIG. 2  is used, which base module  100  according to a specific embodiment of the present invention basically consists of one integrally formed component, which can be injection-molded from polypropylene (PP) or a polycarbonate blend, such as polycarbonate with styrene acrylonitrile (PC/SAN) or polycarbonate with acrylonitrile-butadiene-styrene (PC/ABS). The base module  100  of the presently described specific embodiment is a general box-like structure with a closed bottom  101 , a circumferentially extending side plate  102  in the form of four thin-walled side walls connected with each other and connected with the bottom  101 , and an open upper side. Inside the base module  100 , protrusions  110  are provided on the inner wall surface of the side plate  102 , which protrusions  110  are cylindrically formed columns with a center hole, respectively, which annular columns are protruding laterally inward from the side plate  102 , i.e. the protrusions  110  are connected, at their base end, with the closed bottom  101 , and each protrusion  110  is integrally connected with the side plate  102  by means of an integrally formed connection part. Here, in the presently described specific embodiment, 8 protrusions  110  are provided. 
     Each protrusion  110  constitutes an engagement protrusion  110  for engagement with a respective engagement feature of one of the tray inserts  200 ,  300 ,  400 , which will be described later in more detail. In each side wall of the side plate  102 , an open side slot  103  is provided, which side slot  103  extends from the open upper side, i.e. the open upper side continues in the open side slot  103 , thereby constituting four windows of the side plate  102  open to the top. Here, the protrusions  110  only extend over the extent of the respective side wall, i.e. the protrusions  110  do not extend upwards into the open side slot  103 . As a result of the provided side slots  103 , each corner of the rectangular base module  100  constitutes an angular corner post  104  starting from the closed bottom  101  and continuing to the open upper side, which angular corner posts  104  generate sufficient distance between the closed bottom  101  and the open upper side for the base module  100  to be able to receive at least one of the tray inserts  200 ,  300 ,  400  as well as the respective content provided therein, without interacting with another base module  100  stacked on top of it, as is illustrated, for example, in  FIGS. 5 and 19 . Accordingly, the base module  100  is stackable on top of another base module  100  of the same type, resulting in a stackability of the base modules  100  in a space saving manner, independent from the tray insert  200 ,  300 ,  400  provided in each of the stacked base modules  100 . In order to achieve the stacking connection between at least two base modules  100  on top of each other, the bottom side of the bottom  101  of each base module  100  comprises a step portion  105  with reduced outer circumference, i.e. the step portion  105  is formed as a narrowing step portion, which step portion  105  matches into an inner side of an upper edge of the open side of another base module  100 , or more specifically into the inner side of the thin-walled angular corner posts  104  of such base module  100 . Accordingly, the step portion  105  on the bottom  101  of the upper base module  100  can be stacked into an upper edge of the open side of another base module  100 , e.g. in a nestable manner, see  FIGS. 5 and 19 . As can also be gathered from  FIGS. 5 and 19 , besides a weight reduction of the base module  100 , the side slots  103  in the side plate  102  of each base module  100  also result in an improved visibility of the content of the respective tray insert  200 ,  300 ,  400  from the outside, which further improves the handling, such as transport or the like, of the multipurpose trays  20 ,  30 ,  40 . 
     Furthermore, as shown in most of the drawings, such as in, for example,  FIGS. 1 to 5 , the base module  100  comprises two handles  106  on its outer circumference, i.e. on the outer side of the side plate  102 , for improved transportability of the base module  100  by an operator, wherein the handles  106  are provided in opposite side walls, thus opposite to each other, and wherein each handle  106  simplifies a grasping of the base module  100  by the operator. The handles  106  are provided in an integral manner inside the side plate  102 , i.e. formed in the manner of side pockets protruding into the inside of the base module  100 , as can be gathered from  FIG. 2 . Here, it is to be noted that the handles  106  do not interfere with the step portion  105  and, thus, do not interfere with the stackability feature of the base module  100 . Furthermore, since the open side of the handle  106 , i.e. the open side of the pocket formed by the handle  106  is open to the side, an operator is able to grasp into the respective handle  106  even when the base module  100  is stacked on top of another base module  100 , see also  FIGS. 5 and 19 . 
     Moreover, the base module  100  of the presently described specific embodiment can comprise, as a further interface, an engagement indentation  1061  on its outer circumference, as can be gathered from the enlarged detail illustration in  FIG. 3  in a partial cross sectional view along line A-A. Here, the engagement indentation  1061  is not to be confused by one of the handles  105  itself as described above, but is particularly provided inside the inner structure of the respective handle  105  for a tray carrier, or tray carrier instrument such as a tray shuttle or the like, of the automated processing system, for improved transportability of the base module  100  by the tray carrier in the course of an automated transportation process. In more detail, one or more engagement indentations  1061  are provided within each handle  105 , wherein each engagement indentation  1061  is formed in the shape of a notch provided inside a handle pocket of each handle  105 . 
     As further feature of the base module  100  as depicted in  FIG. 2 , the base module  100  comprises a rotatable color indicator  107  for indication of a loading status of a content of a multipurpose tray  20 ,  30 ,  40 , i.e. a content of a tray insert  200 ,  300 ,  400  as received in the base module  100  of the multipurpose tray  20 ,  30 ,  40 . Here, the color indicator  107  is provided in the form of a manually operable rotating indicator pin or pole arranged in a respective stud hole provided in one of the corner posts  104  of the base module  100 , wherein the stud hole comprises a viewing window  1041  to the outside of the base module  100 , in which the respective color can be shown and changed by rotation of the color indicator  107 . The color indicator  107  in the form of the described pin embedded in the hole in the respective corner post  104  comprises an actuation portion in the form of a rotary knob  1071 , see also  FIG. 3 . The respective corner post  104  comprising the stud hole for the indicator post  107  exhibits a top indentation  1042  at its top end, in which the rotary knob  1071  is arranged in a rotatable manner, so that the rotary knob  1071  does not extend over the upper edge of the corner post  104 , in order to maintain the stackability property of the base module  100 , see  FIG. 5 . Due to the color indicator  107 , its stud hole and the top indentation  1042  at its top end, the loading direction of the base module  100  can clearly be determined, since, referring to its geometry, a tray comprising the base module  100  can also be loaded into loading slots of an automated processing system with a turn of  180 ° around its Z-pivot, i.e. with the color indicator  107  on its back end, since the structural marks in the form of the color indicator  107 , its stud hole and the top indentation  1042  at its top end are detectable by optical sensors of the automated processing system, enabling the same to detect if the tray was wrongly provided into one of the loading slots. Here, following states can be detected: “Tray not available”, “Tray available”, and “Tray available (inverted loading with a turn of 180°)” 
     As one particular color example, the color indicator  107  can provide four different colors, which can indicate that the multipurpose tray  20 ,  30  has new, i.e. unprocessed, content, already processed content, content designated for the archive, or erroneous content, wherein the unprocessed content can be color-coded with green color and the already processed content, or alternatively erroneous content, can be color-coded with red color. Also, in case that the multipurpose tray  40  carries content that is not in need of loading status indication, for example in case the tray insert  400  carries consumable tips or the like, i.e. content without any status, a so-called blind plug can be fitted into the stud hole of the corner post  104  instead of the color indicator  107 , i.e. a plug without any different colors provided on it, such as a grey-colored plug or the like. Accordingly, the color indicator can be replaced, if desired, for improved user convenience. The color indicator  107  as described above is particularly useful when using the universal tray insert  200  which can hold different kinds of sample tubes, or when using a urine sample container tray  300 . On the other hand, a blind plug can be reasonable when using a consumable tips carrying tray insert  400 , as mentioned before. Here, such blind plug can have the same structural design as the color indicator  107 , however without any color markings on its outer circumference. 
     According to a further aspect of the presently discussed specific embodiment of the inventive base module  100 , the base module  100  can comprise two writable surfaces  108  on the outer circumference of the side plate  102 , in order for an operator to provide the base module  100  with a human readable marking and allowing rapid marking and erasing of such markings on the surface of the base module  100  by a human operator, if desired, wherein each writable surface  108  is implemented by means of a whiteboard material, i.e. a wipeable material. Moreover, the base module  100  can have one or several identification codes  109  on its outer circumference, which can be an adhesive label or the like, carrying a human-readable machine-writing or a machine-readable identification code  109  implemented by a barcode, both of which are provided on the side plate  102  of the base module  100  as illustrated in  FIG. 2 . 
     In  FIG. 3 , a multipurpose tray  20  is shown, similar to the illustration on the left side of  FIG. 1 , comprising the above described base module  100 , with an empty universal tray insert  200  inserted therein, without any sample tubes arranged in the universal tray insert  200 . Here, it is to be noted that the universal tray insert  200  can be provided in one single piece inserted into the base module  100 , but the universal tray insert  200  can also be provided in the form of two or more pieces, for easier insertion. Furthermore, in this specific embodiment of a multipurpose tray  20 , however, only one writable surface  108  but two identification codes  109  carrying a human-readable machine-writing and one machine-readable identification code  109  are provided on the outer circumference of the side plate  102 . The remaining features of the base module  100  are identical to the above described base module  100 , i.e. the basic structure of the base module  100  is maintained, wherein the application of external features, i.e. the application of writable surfaces  108  or identification codes  109  on the outside of the base module  100 , slightly varies. 
     As can be gathered from  FIGS. 3 and 4 , the universal tray insert  200  comprises  8  circular engagement recesses  210  on its outer edge, which engagement recesses  210  establish a form-fit connection in the form of a releasable push-in connection with the protrusions  110  of the base module  100 , i.e. the protrusions  110  of the base module  100  provide a tongue of a tongue-and-groove connection, wherein the engagement recesses  210  of the tray insert  200  provide the groove counterpart. Also, the circumferential edge of the entire universal tray insert  200  matches the inner circumference of the side plate  102  of the base module  100 , which supports the releasable push-in connection between base module  100  and universal tray insert  200 . Furthermore, as can be gathered particularly from  FIG. 4  which shows the multipurpose tray  20  of  FIG. 3  from a different viewing angle, fiducial markers  220  are provided at the edge of an upper surface of the universal tray insert  200 , which fiducial markers  220  are used for clear allocation of each of the tube receiving recesses in the universal tray insert  200  and can be provided in the form of a grid consisting of alphabetic characters and/or numbers, for identifying each tube receiving recess in the universal tray insert  200 . Here, in the embodiment as depicted in  FIG. 4 , the fiducial markers  220  designating the rows of tube receiving recesses are shown in capital letters. However, as an alternative, the fiducial markers  220  could also be provided on the outer circumference of the side plate  102  of the base module  100 , for example by printing or by means of additional adhesive labels. 
     Regarding the structure of tube receiving recesses in the universal tray insert  200  of the presently described specific embodiment, there are several different kinds of tube receiving recesses provided as a tube receiving recess array in the universal tray insert  200  as shown in  FIGS. 1 and 3 to 5 , which can clearly be derived from the detail of a top view of a left side of the multipurpose tray  20  as shown in  FIG. 6 . Here, the array of tube receiving recesses comprises a first group of tube receiving recesses  201  with a large diameter, in order to receive sample tubes with a large outer diameter, such as PreservCyt tubes, a second group of tube receiving recesses  202  with a middle sized diameter, i.e. a smaller diameter compared to the tube receiving recesses  201 , in order to receive sample tubes with a middle sized outer diameter, such as SurePath tubes, and a third group of tube receiving recesses  203  with a small diameter, i.e. an even smaller diameter compared to the other tube receiving recesses  201 ,  202 , in order to receive sample tubes with a small outer diameter, such as PCR tubes. For clarification, in the enlarged detail of the universal tray insert  200  as shown in  FIG. 6 , 6 full, i.e. uncropped, tube receiving recesses  201  of the first group,  10  full tube receiving recesses  202  of the second group, and 24 full tube receiving recesses  203  of the third group are shown. Moreover, for illustrative reasons only, one exemplary sample tube  501  with a large outer diameter is shown in one of the tube receiving recesses  201  of the first group in the left column in the middle position, depicted by means of a dashed circular line and arranged next to the capital letters “C” and “D” of the fiducial markers  220 , one exemplary sample tube  502  with a middle sized diameter is shown in one of the tube receiving recesses  202  of the second group in the second to left column in the uppermost position, depicted by means of a dashed circular line, and one exemplary sample tube  503  with a small diameter is shown in one of the tube receiving recesses  203  of the third group in the left column in the second position counted from the lower side of the illustration, depicted by means of a dashed circular line and arranged next to the capital letter “E” of the fiducial markers  220 . Here, in order to depict the correlation between the diameters of the exemplary sample tubes  501 ,  502 ,  503  and the intersecting tube receiving recesses  201 ,  202 ,  203 , the intersecting parts of the same are also depicted in a dashed circular manner, for the sake of improved perceptibility. Here, as an optional feature, the inner diameter of each tube receiving recess  201 ,  202 ,  203  can provide lash/tolerance to some extent, so that a respective sample tube  501 ,  502 ,  503  provided with one or several labels on its outer circumference can still fit into the respective tube receiving recess  201 ,  202 ,  203 . 
     As described above, the size of a tube receiving recess  201  of the first group, the size of a tube receiving recess  202  of the second group and the size of a tube receiving recess  203  of the third group differ from each other, i.e. the recess sizes between those groups are different to each other. Moreover, a contour of an inner circumference of each tube receiving recess  201  of the first group, which basically coincides with the dashed circular line of the large diameter sample tube  501 , intersects with a contour of an inner circumference of at least one adjacent tube receiving recess  202  of the second group, which basically coincides with the dashed circular line of the middle diameter sample tube  502 . Here, as contour of a tube receiving recess inner circumference, an outline of the tube receiving recess inner circumference is to be understood, wherein the contour or outline of the tube receiving recess inner circumference also be identified as the substantial cross-section of the respective tube receiving recess when viewed from above, as in  FIG. 6 . However, as can also be gathered from  FIG. 6 , the inner circumferences of the tube receiving recesses  201 ,  202  of both the first group and the second group are not continuous, since the tube receiving recesses  201 ,  202  of both groups intersect with each other, thus exhibiting an intersection of the contour of a tube receiving recess inner circumference of the first group of tube receiving recesses  201  with the contour of an inner circumference of at least one adjacent tube receiving recess  202  of the second group of tube receiving recesses  202 . Also, the intersection of contours of the first group of tube receiving recesses  201  and the second group of tube receiving recesses  202  constitutes a non-tangential crossover of contours, meaning that the contour of an inner circumference of each tube receiving recess  201  of the first group crosses the contour of an inner circumference of at least one adjacent tube receiving recess  202  of the second group in a non-tangential manner. Such arrangement of tube receiving recesses  201 ,  202  specifically assists in achieving the optimized way of fitting tubes with two differing diameters into the universal tray insert  200 , in order to achieve an increase in receivable tube number that can be inserted into the universal tray insert  200 . 
     Furthermore, it is to be noted that a center axis  2011  of each respective tube receiving recess  201  of the first group is arranged in an eccentric manner in relation to a center axis  2021  of an adjacent tube receiving recess  202  of the second group, meaning that the center axes  2011 ,  2021  of both groups of tube receiving recesses  201 ,  202  do not coincide with each other, which additionally assists in achieving the already described optimized way of fitting tubes with differing diameters into the universal tray insert  200 . Here, the distances between the respective axes  2011 ,  2021  are set in a way in accordance with the respective sample tubes  501 ,  502  to be loaded so that a “wrong” loading of the sample tubes  501 ,  502  into the universal tray insert  200  is not possible, or at least can easily be detected by the operator during loading. Moreover, a depth of each tube receiving recess  201  of the first group can be different from a depth of each tube receiving recess  202  of the second group, depending on the length of the respective sample tubes  501 ,  502  to be inserted therein. Thereby, sample tubes  501 ,  502  with differing length can also be received by the universal tray insert  200 , wherein the depth of the different groups of tube receiving recesses  201 ,  202  can be chosen such that the tops of sample tubes having a longer length do not or only slightly protrude compared to the other group of tubes having a shorter length. 
     As already described above, the tube receiving recess array of the universal tray insert  200  of the multipurpose tray  20  comprises the tube receiving recesses  203  of the third group, additionally to the already described first and second groups of tube receiving recesses  201 ,  202 , wherein a contour of an inner circumference of at least one of tube receiving recesses  203  of the third group, which basically coincides with the dashed circular line of the small diameter sample tube  503 , intersects with a contour of an inner circumference of at least one adjacent tube receiving recess  201 ,  202  of the first and/or second group. Here again, as contour of an inner circumference of a tube receiving recess  203 , an outline of the inner circumference of the tube receiving recess  203  is to be understood, wherein the contour or outline of the inner circumference of the tube receiving recess  203  can also be identified as the substantial cross-section of the tube receiving recess  203  when viewed from above. Also, a center axis  2031  of each respective tube receiving recess  203  of the third group is arranged in an eccentric manner in relation to the center axis  2011  of an adjacent tube receiving recess  201  of the first group and to the center axis  2021  of an adjacent tube receiving recess  202  of the second group, meaning that the center axes  2011 ,  2021 ,  2031  of all groups of tube receiving recesses  201 ,  202 ,  203  do not coincide with each other. However, regarding the contour of the tube receiving recesses  203 , it has to be noted that, different from the contours of the tube receiving recesses  201 ,  202 , each contour of the tube receiving recesses  203  comprises  4  axial slots  2032  provided in a manner of always two slots  2032  being arranged opposite of each other, i.e. resulting in a general X-shape of the axial slots  2032 . The axial slots  2032  are provided for manufacturing reasons. 
     In addition to the respective observations above regarding the first and second groups of tube receiving recesses  201 ,  202 , the inner circumferences of the tube receiving recesses  201 ,  202 ,  203  of all three groups of the presently described specific embodiment are not continuous, wherein the tube receiving recesses  201 ,  202 ,  203  of all groups can intersect with each other when viewed from above, thus exhibiting an intersection of the contour of an inner circumference of each tube receiving recess  201  of the first group with the contour of an inner circumference of at least one adjacent tube receiving recess  202  of the second group and also with the contour of an inner circumference of at least one adjacent tube receiving recess  203  of the third group. This additionally assists in achieving the already described optimized way of fitting tubes with differing diameters into the universal tray insert  200 . Further, the distances between the respective axes  2011 ,  2021 ,  2031  are set in a way in accordance with the respective sample tubes  501 ,  502 ,  503  to be loaded so that a “wrong” loading of the sample tubes  501 ,  502 ,  503  into the universal tray insert  200  is not possible, or at least can easily be detected by the operator during loading. With such a particular structure of tube receiving recesses  201 ,  202 ,  203  with differing sizes, the design of the universal tray insert  200  can be further improved in that it can receive three different container shapes or sizes of the sample tubes  201 ,  202 ,  203 , wherein it again becomes possible to merge smaller containers closer together than bigger containers. Accordingly, the three differing types of sample tubes  501 ,  502 ,  503  with three differing diameters can fit in the universal tray insert and, thus, in the respective multipurpose tray, always in an optimized way, in order to achieve an increase in receivable tube number that can be inserted into the universal tray insert  200 . For example, in case only one of the three different sample tube types is loaded into the universal tray insert  200  of the presently described design, it becomes possible to load 21 pieces of sample tubes  501  with large diameter, such as PreservCyt tubes, 32 pieces of sample tubes  502  with a middle sized diameter, such as SurePath tubes, or 78 pieces of sample tubes  503  with a small diameter, such as PCR tubes. Thus, the universal tray insert  200  of the presently described specific embodiment can receive between 21 and 78 sample tubes, of the same type or of different types in a mixed manner, depending on the composition of loaded sample tubes  501 ,  502 ,  503 . 
     Regarding the depth of the tube receiving recesses  203  of the third group, it has to be noted that the same are partially provided in the bottom of one or several of the tube receiving recesses  201 ,  202  of the first and second group, meaning that the depth of the tube receiving recess  203  of the third group is deeper than the depth of the tube receiving recesses  201 ,  202  of the first and second group. This can also be gathered from  FIGS. 3 and 4 . Based on the different depths, the different sizes and the eccentric arrangement of the tube receiving recesses  201 ,  202 ,  203  of all groups, the universal tray insert  200  comprises brackets  204  protruding from a bottom of the universal tray insert  200  and surrounding the tube receiving recesses  201 ,  202 ,  203 , which brackets  204 —when fully shaped, i.e. not provided at the edge of the universal tray insert  200  but rather to the middle-exhibit a substantial shape in the form of the capital letter “H”. 
     With the above described structure of the universal tray insert  200 , different types of sample tubes  501 ,  502 ,  503  with differing diameters can fit in the universal tray insert  200  and, thus, in the respective multipurpose tray  20 , always in an optimized way, in order to achieve an increase in receivable tube number that can be inserted into the universal tray insert  200 , see also  FIGS. 7 to 10 . Here, as an example as depicted in  FIGS. 7 to 10 , 6 large diameter sample tubes  501 , such as PreservCyt tubes, 12 middle diameter sample tubes  502 , such as SurePath tubes, and 36 small diameter sample tubes  503 , such as PCR tubes, are loaded into the universal tray insert  200  of the multipurpose tray  20 , in a mixed manner. 
     However, the universal tray insert  200  can also only be filed with one single type of sample container. Here, with the above described structure of the universal tray insert  200  of the presently described embodiment of the multipurpose tray  20  and as shown in  FIGS. 11 and 12 , in case only sample tubes  502  with large diameter are loaded into the universal tray insert  200  in an optimized way, up to 21 large diameter sample tubes  501 , such as PreservCyt tubes, can fit in the universal tray  200 . Moreover, as shown in  FIGS. 13 and 14 , in case only sample tubes  502  with middle sized diameter are loaded into the universal tray insert  200  in an optimized way, up to 32 middle sized diameter sample tubes  502 , such as SurePath tubes, can fit in the universal tray  200 . Finally, as shown in  FIGS. 15 and 16 , in case only sample tubes  503  with small diameter are loaded into the universal tray insert  200  in an optimized way, up to 78 small diameter sample tubes  502 , such as PCR tubes, can fit in the universal tray  200 . Moreover, as can also be gathered from, for example,  FIG. 16 , the universal tray insert  200  comprises a color indicator groove  230  provided in order to leave out the space required for the stud hole in the one of the corner posts  104  of the base module  100  comprising the color indicator  107 . Here, on the opposite corner of the universal tray insert  200 , another color indicator groove  230  is provided, which renders it irrelevant how the universal tray insert  200  is actually inserted into the inner side of the base module  100 , since it is also can be inserted in a 180°-turned-around manner. 
     In  FIG. 17 , an alternative multipurpose tray  20 ′ is shown in full in a top view, similar to the illustration of the partially shown multipurpose tray  20  of  FIG. 6 , comprising the above described base module  100 , with an alternative empty universal tray insert  200 ′ inserted therein, without any sample tubes arranged in the alternative universal tray insert  200 ′. Here, it is to be noted that the universal tray insert  200 ′ can also be provided in one single piece inserted into the base module  100 , but the universal tray insert  200 ′ can also be provided in the form of two or more pieces, for easier insertion, which pieces can be attached to each other. The remaining features of the base module  100  of  FIG. 17  are identical to the above described base module  100 , i.e. the basic structure of the base module  100  is maintained, wherein the application of external features, i.e. the application of writable surfaces  108  or identification codes  109  on the outside of the base module  10  can vary. For example, in the base module  100 , a magnet can be provided, for example embedded in the bottom  101  of the base module  100 , wherein an automated processing system handling the tray  20 ′, e.g. a tray carrier instrument such as a tray shuttle or the like, can comprise a Hall sensor, which changes its state as soon as the magnet approaches the sensor, i.e. as soon as the tray  20 ′ is loaded. Thereby, the automated processing system can acknowledge the presence of the loaded tray  20 ′. 
     As can further be gathered from  FIG. 17 , the alternative universal tray insert  200 ′ also comprises circular engagement recesses establishing a connection in the form of a releasable push-in connection with the protrusions  110  of the base module  100 . Also, similar to the previously described multipurpose tray  20 , the alternative multipurpose tray  20 ′ of  FIG. 17  comprises fiducial markers  220 ′ provided at the edge of an upper surface of the universal tray insert  200 ′, which fiducial markers  220 ′ are used for clear allocation of each of the tube receiving recesses in the universal tray insert  200 ′ and can be provided in the form of a grid consisting of alphabetic characters and/or numbers, for identifying each tube receiving recess in the universal tray insert  200 ′. Here, in the alternative embodiment as depicted in  FIG. 17 , the fiducial markers  220 ′ designating the rows of tube receiving recesses are shown in capital letters A to I. 
     Regarding the structure of tube receiving recesses in the alternative universal tray insert  200 ′ of the presently described alternative embodiment, there are several different kinds of tube receiving recesses provided as a tube receiving recess array in the alternative universal tray insert  200 ′, wherein the tube receiving recess array in the alternative universal tray insert  200 ′ differs from the tube receiving recess array in the universal tray insert  200 . In particular, the array of tube receiving recesses comprises a first group of tube receiving recesses  201 ′ with a large diameter, in order to receive sample tubes with a large outer diameter, such as PreservCyt tubes, a second group of tube receiving recesses  202 ′ with a middle sized diameter, i.e. a smaller diameter compared to the tube receiving recesses  201 ′, in order to receive sample tubes with a middle sized outer diameter, such as SurePath tubes, and a third group of tube receiving recesses  203 ′ with a small diameter, i.e. an even smaller diameter compared to the other tube receiving recesses  201 ′,  202 ′, in order to receive sample tubes with a small outer diameter, such as PCR tubes. As described above, the size of a tube receiving recess  201 ′ of the first group, the size of a tube receiving recess  202 ′ of the second group and the size of a tube receiving recess  203 ′ of the third group differ from each other, i.e. the recess sizes between those groups are different to each other. Moreover, a contour of an inner circumference of each tube receiving recess  201 ′ of the first group intersects with a contour of an inner circumference of at least one adjacent tube receiving recess  202 ′ of the second group. Here, as contour of a tube receiving recess inner circumference, an outline of the tube receiving recess inner circumference is to be understood, wherein the contour or outline of the tube receiving recess inner circumference can also be identified as the substantial cross-section of the respective tube receiving recess when viewed from above. However, as can also be gathered from  FIG. 17 , the inner circumferences of the tube receiving recesses  201 ′,  202 ′ of both the first group and the second group are not continuous, since the tube receiving recesses  201 ′,  202 ′ of both groups intersect with each other, thus exhibiting an intersection of the contour of a tube receiving recess inner circumference of the first group of tube receiving recesses  201 ′ with the contour of an inner circumference of at least one adjacent tube receiving recess  202 ′ of the second group of tube receiving recesses  202 ′. Also, the intersection of contours of the first group of tube receiving recesses  201 ′ and the second group of tube receiving recesses  202 ′ constitutes a non-tangential crossover of contours, meaning that the contour of an inner circumference of each tube receiving recess  201 ′ of the first group crosses the contour of an inner circumference of at least one adjacent tube receiving recess  202 ′ of the second group in a non-tangential manner. Such arrangement of tube receiving recesses  201 ′,  202 ′ specifically assists in achieving a further optimized way of fitting tubes with two differing diameters into the alternative universal tray insert  200 ′, in order to achieve an increase in receivable tube number that can be inserted into the universal tray insert  200 ′. Here, in view of the alternative embodiment of the universal tray insert  200 ′, it is pointed out that the differing distribution of recesses  201 ′,  202 ′ and  203 ′ has been chosen in order to achieve a further advantage, i.e. that more space is provided for fingers of a sample tube gripper or the like, in order for the same to be able to better grip the tubes that need to be gripped further down, i.e. at a lower position on the outside of the respective sample tube. 
     As already described above, the tube receiving recess array of the alternative universal tray insert  200 ′ of the alternative multipurpose tray  20 ′ comprises additionally the tube receiving recesses  203 ′ of the third group, in addition to the already described first and second groups of tube receiving recesses  201 ′,  202 ′, wherein a contour of an inner circumference of at least one of tube receiving recesses  203 ′ of the third group can intersect with a contour of an inner circumference of at least one adjacent tube receiving recess  201 ′,  202 ′ of the first and/or second group. Here again, as contour of an inner circumference of a tube receiving recess  203 ′, an outline of the inner circumference of the tube receiving recess  203 ′ is to be understood, wherein the contour or outline of the inner circumference of the tube receiving recess  203 ′ can also be identified as the substantial cross-section of the tube receiving recess  203 ′ when viewed from above. As can be gathered from  FIG. 17 , within each of the tube receiving recesses  203 ′, tube springs  205 ′ are provided, in order to be able to securely hold tubes with an even smaller cross-section, such as tubes with a cross-section of 12 mm or 14 mm, wherein—in the present embodiment—each tube receiving recess  203 ′ exhibits an exemplary number of three tube springs  205 ′ in order to be able to securely hold a tube with an even smaller cross-section in a centric manner within the recess  203 ′. Of course, the number of tube springs  205 ′ can also be different, as long as the tube with an even smaller cross-section can be hold in a centric manner. Here, the tube springs  205 ′ are at least in part inserted into the inner circumference of the tube receiving recess  203 ′ so that merely tube contact parts of the tube springs  205 ′ protrude therefrom. Also, a center axis of each respective tube receiving recess  203 ′ of the third group is again arranged in an eccentric manner in relation to the center axis of an adjacent tube receiving recess  201 ′ of the first group and to the center axis of an adjacent tube receiving recess  202 ′ of the second group, similar to the previously described universal tray insert  200 , meaning that the center axes of all groups of tube receiving recesses  201 ′,  202 ′,  203 ′ do not coincide with each other. Accordingly, the three differing types of sample tubes  501 ,  502 ,  503  with three differing diameters can also fit in the alternative universal tray insert  200 ′ and, thus, in the respective alternative multipurpose tray  20 ′, always in a specifically optimized way, particularly optimized for improved gripping of each tube, in order to achieve an increase in receivable and graspable tube number that can be inserted into the alternative universal tray insert  200 ′. For example, in case only one of the three different sample tube types is loaded into the alternative universal tray insert  200 ′ of the presently described design as shown in  FIG. 17 , it becomes possible to load 20 pieces of sample tubes  501  with large diameter, such as PreservCyt tubes, 20 pieces of sample tubes  502  with a middle sized diameter, such as SurePath tubes, or 62 pieces of sample tubes  503  with a small diameter, such as PCR tubes. Thus, the alternative universal tray insert  200 ′ of the presently described alternative embodiment can receive between 20 and 62 sample tubes, of the same type or of different types in a mixed manner, depending on the composition of loaded sample tubes  501 ,  502 ,  503 . 
     Regarding the depth of the tube receiving recesses  203 ′ of the third group, it has to be noted that the same are partially provided in the bottom of one or several of the tube receiving recesses  201 ′,  202 ′ of the first and second group, meaning that the depth of the tube receiving recess  203 ′ of the third group is deeper than the depth of the tube receiving recesses  201 ′,  202 ′ of the first and second group, similar to the embodiment of universal tray insert  200  as described before. However, contrary to the embodiment of universal tray insert  200  as described before, the alternative universal tray insert  200 ′ of the presently described alternative embodiment comprises the already mentioned upper surface of the universal tray insert  200 ′, which exhibits the fiducial markers  220 ′, and in which the different tube receiving recesses  201 ′,  202 ′,  203 ′ are provided into the upper surface of the universal tray insert  200 ′ towards the bottom  101  of the base module  100 . Thereby, the different depths, different sizes and the eccentric arrangement of the tube receiving recesses  201 ′,  202 ′,  203 ′ are established, wherein the arrangement of tube receiving recesses  201 ′,  202 ′,  203 ′ of the universal tray insert  200 ′ results in an outer circumference of upper surface and two connecting elements in the form of division bars or division bridges  204 ′ instead of the brackets  204  of the universal tray insert  200 . Thus, the particular surface structure with protruding brackets  204  is omitted in the universal tray insert  200 ′, resulting in a smooth and substantially continuous upper surface of the universal tray insert  200 ′, of course except for the recesses  201 ′,  202 ′,  203 ′, wherein, in the present case, for the sake of improved utilization of space, additional independent tube recesses  203 ′ are provided into the upper surface of the universal tray insert  200 ′, exemplary shown in  FIG. 17  in the form of two additional independent tube recesses  203 ′ on the left side of the illustration. 
     In  FIG. 18 , as an alternative specific embodiment, the multipurpose tray  30  as depicted in the middle position of  FIG. 1  is shown, which comprises the base module  100  as shown in  FIG. 2  and as used in correlation with the previously described universal tray inserts  200 ,  200 ′ and in which a urine sample tray insert  300  for urine sample containers is inserted, without any urine sample containers arranged in the urine sample tray insert  300 . Here, in order to avoid the repetition of the description of identical features, only the differences vis-à-vis the previously described specific embodiment are described. In particular, the base module  100  is identical to the base module  100  as described in view of  FIGS. 1 to 17 . Similarly to the universal tray inserts  200 ,  200 ′ as described above, the urine sample tray insert  300  is inserted into the base module  100  by means of the same tongue-and-groove connection, wherein the urine sample tray insert  300  is shown in a bisected manner, i.e. the urine sample tray insert  300  consists of two halves which are both identical and inserted into the base module  100 , see also the color indicator groove at the edge. The urine sample tray insert  300  provides urine sample container recesses  301  for  20  urine sample containers  601 , see also  FIG. 19 , in which two multipurpose trays  30  are stacked on top of each other. Here again, corner posts  104  generate sufficient distance between the closed bottom  101  and the open upper side for the base module  100  to be able to receive the urine sample tray insert  300  as well as the respective urine sample containers  601  provided therein, without interacting with the other base module  100  stacked on top of it. 
     In  FIG. 20 , as a further alternative specific embodiment, the multipurpose tray  40  as arranged on the right side of  FIG. 1  is shown, comprising a base module  100  as shown in  FIG. 2  and as used in correlation with the previously described universal tray inserts  200 ,  200 ′,  300 , and in which a tip rack tray insert  400  with four tip racks  410  inserted therein is shown, wherein one consumable pipette tip  701  is arranged in a tip rack hole  401  or tip rack opening in one of the tip racks of the tip rack tray insert  400  as exemplary content. Here, in order to avoid the repetition of the description of identical features, only the differences vis-à-vis the previously described specific embodiment are described. In particular, the base module  100  is identical to the base module  100  as described in view of  FIGS. 1 to 19 . In contrast to the universal tray inserts  200 ,  200 ′ and the urine sample tray insert  300  as described above, the tip rack tray insert  400  is not inserted into the base module  100  by means of the tongue-and-groove connection, due to the overly long pipette tips. However, the tip rack tray insert  400  comprises plug connectors  420  provided on the bottom of the tip rack tray insert  400 , which plug connectors  420  are implemented in the form of downwardly protruding pins with a portion with reduced diameter on its lower end. Here, the reduced diameter portions of the plug connectors  410  can be removably inserted, i.e. removably plugged, into the center holes of the protrusions  104 , which holes are open to the open side of the base module  100  and which are provided to receive the plug connectors  420 , thereby establishing a push-in connection as mentioned above, which can be detached again. Further, the four tip racks  410  are inserted into the tip rack tray insert  400  from above by means of a snap-fit connection or the like. 
     Each tip rack  410  provides  96  tip rack holes  401 , resulting in an overall loading capacity of the tip rack tray insert  400  of  384  consumable pipette tips Further, as shown in  FIG. 20 , each tip rack  410  comprises a barcode  411  on one side of the tip rack tray insert  400 , as well as a mark on the tip rack tray insert  400 , according to which the operator has to load the tip racks  410 . 
     As mentioned before, a centering spring  800  can be provided inside, for example, at least one of the tube receiving recesses  201 ,  201 ′,  202 ,  202 ′,  203 ,  203 ′ for centering and holding a smaller sample tube inside one of the tube receiving recesses  201 ,  201 ′,  202 ,  202 ′,  203 ,  203 ′ in case the respective tube receiving recess  201 ,  201 ′,  202 ,  202 ′,  203 ,  203 ′ has a larger inner diameter than the outer diameter of the sample tube to be held. Accordingly, the centering spring  800  has a similar function as the above mentioned tube spring  205 ′. Accordingly, such a centering spring  800  can further improve the universal property of the universal tray inserts  200 ,  200 ′, since the universal tray inserts  200 ,  200 ′ can be universally used for a greater plurality of different kinds of sample tubes, i.e. 
     exceeding the three differently sized sample tubes  501 ,  502 ,  503 . Here, as a specific example, the centering spring  800  is made of spring steel and comprises a substantially circular, or hexagonal, middle part  810  for attachment inside a respective tube receiving recess  201 ,  201 ′,  202 ,  202 ′,  203 ,  203 ′, and  3  clamp arms  820  protruding away from the middle part  810  in a longitudinal manner on each side of the middle part  810 , each clamp arm  820  comprising an inwardly protruding nib  830  at its end, for contacting the sample tube to be held, thereby holding and centering the same in coaxial manner with the centering spring  800  itself, i.e. with the respective tube receiving recess  201 ,  201 ′,  202 ,  202 ′,  203 ,  203 ′, in a clamped manner. The nib  830  is formed in a V-shape with the pointed end  831  directed inward, as contact point with the sample tube to be held. since at least  3  clamp arms  820  are provided on each side of the middle part  810 , a three-point spring support is achieved by the centering spring  800 , enabling the centering and holding of a sample tube inside the centering spring  800 . 
     In addition to the above, as further specific embodiments of multipurpose trays to be used for an analyzer, and due to the fact that the base module  100  can exhibit the size of 1×4 SBS (society of biomolecular screening=standard for microplate sizes), an insert with empty microwell plates for further processing can be inserted into the base module  100 . Furthermore, an insert for carrying reagents can also be considered, for example in the form of 4 MGP (magnetic glass particle) cassettes provided in the tip rack tray insert  400  instead of the tip racks  410 . 
     According to a specific embodiment of the present invention, a method of simplified loading/unloading of a multipurpose tray into/from an automated processing system by an operator is shown in  FIG. 22 . Further, an exemplary loading/unloading station  10  of the automated processing system is shown in  FIG. 23 , wherein an arrangement of the loading slots  12  and unloading slots  13  of  FIG. 23  is shown in  FIG. 24  in a more specific embodiment. The loading/unloading station  10  of the automated processing system can comprise a flap door  11  for covering the loading slots  12  and unloading slots  13 , if desired, in order to avoid any disturbance of the loaded multipurpose trays, or also of a multipurpose tray to be unloaded, as illustrated in one of the unloading slots  13  in  FIG. 23 . Here, such a multipurpose tray can be one of the multipurpose trays  20 ,  20 ′  30 ,  40  as described above in detail, or, alternatively, another kind of multipurpose tray having any kind of tray insert inserted in its base module  100 , wherein the technical features mentioned in its context in regard to the structure of the multipurpose tray also apply for the method of the present invention and are, thus, not repeated at this point. In further detail, the method comprises the following steps, which can be arranged in the following order in line with the flowchart of  FIG. 22 : 
     Decision step  910 : Determining if the multipurpose tray  20 ,  20 ′,  30 ,  40  to be loaded into a loading slot  12  contains prioritized content. 
     Execution step  920 : In case the determination in decision step  910  results in the multipurpose tray  20 ,  20 ′,  30 ,  40  to be loaded into a loading slot  12  containing prioritized content, loading the multipurpose tray  20 ,  20 ′,  30 ,  40  into a priority loading slot  121  of the automated processing system by the operator. 
     Execution step  930 : In case the determination in decision step  910  results in the multipurpose tray  20 ,  20 ′,  30 ,  40  to be loaded into a loading slot  12  does not contain prioritized content, loading the multipurpose tray  20 ,  20 ′,  30 ,  40  into any loading slot  12  other than the priority loading slot  121  of the automated processing system by the operator. 
     Execution step  940 : Processing the content of the loaded multipurpose tray  20 ,  20 ′,  30 ,  40  by laboratory instrument of the automated processing system. 
     Execution step  950 : Unloading the multipurpose tray  20 ,  20 ′,  30 ,  40  from an unloading slot  13  or from an error-out unloading slot  131  of the automated processing system by the operator. 
     In regard to the execution step  940 , i.e. the step of processing the content of the loaded multipurpose tray  20 ,  20 ′,  30 ,  40  by laboratory instrument of the automated processing system, the automated processing system comprises a sensor recognizing the content of the multipurpose tray  20 ,  20 ′,  30 ,  40  loaded into one of the loading slots  12  without interaction between the operator and software of the automated processing system, i.e. the automated processing system is able to automatically recognize the loaded multipurpose tray  20 ,  20 ′,  30 ,  40  and its content by means of the sensor, such as an optical sensor, an RFID sensor or the like, based on reading, for example, a machine-readable identification code  109  provided on the base module  100  of the multipurpose tray  20 ,  20 ′,  30 ,  40 . Thus, the automated processing system is able to identify the necessary or desired processing steps to be carried out automatically by the laboratory instruments inside the automated processing system, without the necessity for the operator of data input regarding the content of the multipurpose tray  20 ,  20 ′,  30 ,  40 , for example by means of a user interface. 
     In regard to the execution step  950 , the multipurpose tray  20 ,  20 ′,  30 ,  40  to be unloaded from any unloading slot  13  of the automated processing system can be unloaded by the operator from the respective unloading slot  13  without interaction between the operator and software of the automated processing system regarding the format or content of the multipurpose tray  20 ,  20 ′,  30 ,  40 , i.e. the automated processing system allows unloading of the multipurpose tray  20 ,  20 ′,  30 ,  40  without the necessity for the automated processing system to provide data about the multipurpose tray  20 ,  20 ′,  30 ,  40  to be unloaded from any of the unloading slots  13  to the operator, for example by means of a user interface. However, in general, any multipurpose tray  20 ,  20 ′,  30 ,  40  to be unloaded from any of the unloading slots  13  of the automated processing system can only be unloaded by the operator by interaction between the operator and software of the automated processing system, i.e. the automated processing system allows unloading of the multipurpose tray  20 ,  20 ′,  30 ,  40  to only with a respective input from the operator to the system, for example by means of the user interface. Thus, it is not possible to manually unload the multipurpose tray  20 ,  20 ′,  30 ,  40  without interaction between the operator and the software. Only when “unloading” is activated on the user interface, such as a touchscreen, the multipurpose tray  20 ,  20 ′,  30 ,  40  can be unloaded, i.e. when an “unlock” button on the touchscreen has been activated, the multipurpose tray  20 ,  20 ′,  30 ,  40  is provided automatically to the outside, for example by pushing open the flap door  11  of the loading/unloading station  10 . 
     In general, the automated processing system can comprise a control unit carrying application software for interaction with an operator as well as for controlling the workflow inside the automated processing system. Further, the automated processing system can lock any unloading slot  13  for preventing unloading of the multipurpose tray  20 ,  20 ′,  30 ,  40  from the unloading slot  13  before clearance, for example while the respective multipurpose tray  20 ,  20 ′,  30 ,  40  is still in the process of processing step  940 . Accordingly, while the multipurpose tray  20 ,  20 ′,  30 ,  40  is in processing, the automated processing system prevents manual removal of the multipurpose tray  20 ,  20 ′,  30 ,  40  from the respective unloading slot  13 , for example by means of a manual lock. Alternatively, or additionally, the automated processing system can comprise a loading/unloading status indicator for each slot, for example in the form of a LCD display or the like, indicating the status of loading/unloading permission or loading/unloading prohibition for each slot  12 ,  13 . Here, a loading/unloading status indication can be given, as example, by means of the following signs: 
     Displayed sign: ↑ (in green color); Meaning: Load multipurpose tray  20 ,  20 ′,  30 ,  40 ; Task: Multipurpose tray  20 ,  20 ′,  30 ,  40  can be loaded by the operator. 
     Displayed sign: ↓ (in green color); Meaning: Unload multipurpose tray  20 ,  20 ′,  30 ,  40 ; Task: Multipurpose tray  20 ,  20 ′,  30 ,  40  can be unloaded by the operator. 
     Displayed sign: ↓ (in red color); Meaning; Unload multipurpose tray  20 ,  20 ′,  30 ,  40  (buffer has no more capacity); Task: Multipurpose tray  20 ,  20 ′,  30 ,  40  has to be loaded by the operator. 
     Displayed sign:  ; Meaning; Loading slot  12  and/or unloading slot  13  is locked; Task: No task for the operator. 
     Accordingly, the presently described method offers a user-convenient way of loading samples and disposables into an automated processing system, wherein the operator can load the multipurpose tray  20 ,  20 ′,  30 ,  40  comprising supplies and/or samples into any one of the loading slots  12 , without having to identify a loading slot matching the format of content of the multipurpose tray  20 ,  20 ′,  30 ,  40  to be loaded each time a multipurpose tray  20 ,  20 ′,  30 ,  40  has to be loaded into the automated processing system. 
     In the presently described method, the loading/unloading station  10  of the automated processing system is particularly equipped with 8 loading/unloading slots  12 ,  13  as tray interface between the outside and the inside of the automated processing system, wherein the slots  12 ,  13  are arranged in two rows of slots  12 ,  13 , with 4 loading slots  12  on top and 4 unloading slots  13  at the bottom. Here, as illustrated in  FIG. 24 , the loading slot  12  on the right can be designated to be a priority loading slot  121 , wherein the automated processing system carries out the processing step  940  with prioritizing the multipurpose tray  20 ,  20 ′,  30 ,  40  with prioritized content loaded into the priority loading slot  121 . 
     Regarding the execution step  950  of unloading the multipurpose tray  20 ,  20 ′,  30 ,  40  from an unloading slot  13  or from an error-out unloading slot  131  of the automated processing system by the operator, different kinds of multipurpose trays  20 ,  20 ′,  30 ,  40  with differing contents can be unloaded from the unloading slots  13 . However, one of the unloading slots  13  can be designated to be an unloading slot for unloading sample error trays, i.e. an error-out unloading slot  131 , from which multipurpose trays  20 ,  20 ′,  30 ,  40  with sample tubes that have been identified by the automated processing system to exhibit some kind of error, such as an unreadable label or the like, or also in case of an erroneous sample, are to be unloaded. Accordingly, the execution step  950  of unloading the multipurpose tray  20 ,  20 ′,  30 ,  40  can comprise unloading of the multipurpose tray  20 ,  20 ′,  30 ,  40  with predetermined content from a predetermined unloading slot in the form of the error-out unloading slot  131 , wherein the predetermined content can be containers with erroneous samples. 
     While the current invention has been described in relation to its specific embodiments, it is to be understood that this description is for illustrative purposes only. Accordingly, it is intended that the invention be limited only by the scope of the claims appended hereto. Various publications are cited herein, the disclosures of which are incorporated by reference in their entireties.