Method and apparatus for the extraction and handling of biological liquids from thin walled receptacles

Abstract: The invention provides apparatus which comprises a minimum of two sections which can be interengaged with one another, one section being capable of being moved relative to the other, and having means for radially and axially holding the thin-walled tubular receptacle containing a biological liquid sample and being provided with means to ensure that on engagement of the two sections with one another the thin-walled receptacle is ruptured at the required points, the said sections comprising components of the device which are joint structures for the purpose of squeezing the thin-walled receptacle after the receptacle has been ruptured, the section directly receiving the thin-walled receptacle being transparent, so as to make it possible to read identifying marks on the said sample-holding receptacle from without.

Description: The present invention refers to a method and apparatus for handling and extracting biological samples held in receptacles with thin walls such as those obtained by sectioning a tubular element with a number of pockets for the purpose of holding the samples to be analyzed. The present invention offers important characteristics of novelty and inventive activity in relation to the state of the art, enabling biological liquids to be handled in a manner which offers considerable security against external contamination and avoids the possibility of leakage from the sample. The invention is especially applicable to the treatment of blood products, such as whole blood, red cells, serum etc. and facilitates the carrying out of analysis thereof. At the present time blood, red cells, serum, etc. from a sample taken from a donor which is intended, for example, for transfusion are usually stored in PVC pockets together with an anti-coagulant and are duly labelled. The contents of the pockets must be analyzed on numerous occasions, at least for each patient who may be given a transfusion, and in these processes it is highly important to prevent accidental contamination (both contamination of the exterior by the contents of the pocket and contamination of the contents from the exterior) and also to prevent confusion occurring in the identification of the samples. Normally each pocket is provided with a long PVC tube which is filled with liquid from the pocket after extraction and is immediately sealed at several points and at its end by welding the walls of the tube by the high frequency method (or any other method). Thus several segments are formed which contain samples of the liquid and these are stored without being cut or separated from the pocket. The tube and the pocket can be marked (for example with numbers or bar codes) a number of times so that each segment contains at least one distinguishing mark. If high frequency welding is used, the electrodes can leave a notch in the welded joint so that subsequently the segments can be separated from one another by traction leaving both ends completely closed and avoiding any leakage of liquid. This whole process is safe and free of contamination. When the contents of a pocket have to be tested, the last of the segments is separated and the test is carried out on the liquid contained therein. For this purpose a test tube is usually taken and placed on a tube rack, and the segment is cut by means of scissors and is emptied by way of the tube, then the empty segment is thrown away and the test is carried out on the tube, which has previously been marked with the same number as that which identifies the pocket. In these conditions: the sample has ceased to be separately identified upon becoming separated from the segment, upon cutting the segment, a stump or end piece is detached and this must be thrown away, the scissors becomes soiled and must be cleaned for the next sample, upon pouring the liquid into the tube splashing may occur, and there is a risk of contamination of the sample from the exterior, and also from the sample outwards and between samples, and danger to humans of viral or bacterial contamination (by AIDS, HEPATITIS, etc.) The same or similar problems are found with other procedures used to recover liquid from inside the segments. One is therefore drawn to the conclusion that although the creation of a number of aliquot parts from the donated sample by means of segments is a clean and safe system, further use of the said segments is very unsatisfactory due to the fact that it does not afford a high standard of hygiene and is potentially dangerous. US-A-4 846 005 and EP-A-0 350 792 disclose devices for blood gathering and testing. The present invention seeks to overcome the problems described above, by providing a method as defined in claim 1 and an apparatus as defined in claim 2 for extracting and handling blood samples held in container elements with thin walls, enabling the said operations to be carried out safely and aseptically, without any real possibility of actual contact with the analysis personnel and enabling the samples to be identified easily during the whole cycle of tests. In order to achieve its aims, the present invention provides apparatus comprising an intermediate receptacle to receive the tubular element holding the sample of biological liquid, the said receptacle being constructed in a manner which is generally similar to that of a test tube, in order to make it possible for the sample to be handled in a manner similar to that which would be used in the case of a test tube, the said intermediate receptacle internally comprising buffering and centring means for the purpose of receiving the tubular receptacle with thin walls for holding the sample of biological liquid, thus creating a lower small container for collecting the biological liquid which will be released from the tubular element which holds it by any suitable means. The size of the intermediate receptacle must be such that, in relation to the tubular element containing the biological sample it enables pipetting to be carried out, possibly by an automatic device of the said intermediate receptacle. The method for handling the biological liquid samples will therefore basically comprise the following successive stages: Placing a tubular container element, one constructed with thin walls, containing the biological sample inside the intermediate receptacle and engaging it with means for centring and retaining the same. Perforating and cutting or tearing the side wall of the tubular element holding the biological sample at a minimum of one point, preferably close to the lower floor of the said circular element, and optionally, making one or more further perforations in the upper part of the same in order to facilitate an intake of air. Squeezing the tubular element holding the biological sample in order to cause the whole of the said sample to be discharged towards the inside of the intermediate receptacle, or emptying by gravity in the case where an upper intake of air is provided for. Pipetting the sample in order for the same to be subjected to the required analysis. Temporary storage of the device holding the tubular element, which is provided with legible marks for the purpose of identifying the sample. The device for carrying out this procedure should preferably be manufactured from a low cost plastic material, which is provided internally with means for centring and holding the tubular element holding the biological sample and a small container for collecting the biological liquid after the said tubular element has been ruptured and squeezed, means being provided for rupturing the tubular element and for squeezing out its contents. In a preferred embodiment of this method, the intermediate receptacle will be produced from two parts or sections, one of which comprises the centring and holding means for the tubular element which holds the biological sample and likewise, means such as projections, blades or other suitable components for the purpose of making cuts in the tubular element containing the biological sample. In this embodiment one section will preferably be connected to the other, either by being moulded in one piece or by being constructed with external hinges which may be situated in the lower portion of a cover extending lengthwise or laterally. In all cases it must be possible to carry out the method which is the subject of the invention in a convenient and rapid manner and in conditions which are especially aseptic. In order to facilitate understanding of the invention, various drawings are annexed hereto by way of explanatory but non-restrictive example, showing embodiments of the present invention. Figures 1 and 2 are both views in cross-section, shown diagrammatically, of one form of device according to the present invention. Figure 3 shows a view from above of a device according to the present invention, which makes it possible to appreciate the internal visibility of the tubular element, due to the fact that it is transparent. Figure 4 shows a diagrammatic cross-section of the device itself. Figures 5 and 6 are views in perspective of a device according to the present invention, showing the components in an open position and in a closed position, respectively. Figure 7 shows a cross-section of a device according to the present invention showing the positioning of a pipetting needle. According to this invention, in order to handle and extract liquids from receptacles with thin walls, a cut will be made in one of the said receptacles indicated with the numeral 1 in Figure 1, this being the usual tubular unit containing various individual containers of the same sample; in order to carry out various tests, the said unit is placed centrally inside a special device which basically comprises a section 2 for the purpose of holding the tubular element, a section 3 which can be connected to section 2 and which is designed to compress and rupture at various points of receptacle 1, and a section 4 in the lower portion of which a small container is arranged, this said lower portion being preferably common to sections 2 and 3 and preferably designed to catch the sample of liquid to be analyzed. At least one of the said sections or components 2 and 3 will be constructed from a transparent material, in order to make it possible to read from outside the identification marks of the sample which refer to the receptacle containing the sample. After the receptacle 1 with thin walls has been placed in position and centred, this receptacle being preferably constructed from a thin plastic material, the said receptacle will be held in position by means of an abutment 5 which may have various forms, and will be subjected to the action of section 3 of the device, which will in the first place produce transverse compression of the receptacle 1 and will also rupture the walls of the receptacle by contact at several points, one point being preferably situated close to the lower end and another point or points being situated close to the upper portion, in order to permit an intake of air to permit complete emptying of the tube; this will contribute to the compression effect of section 3 upon section 2, thereby squeezing the tube, the contents of which will be conveyed into the lower small container 4 in the form of a liquid mass 6, which will then be available to receive reagents, the said small container being capable of being partially removed it necessary, and also capable of being further handled, all of these operations being carried out by means of a pipetting system as shown diagrammatically in Figure 7 by means of the pipetting needle 7. Alternatively, it is possible to empty the tube by means of a single lower perforation, which is made in such a manner as to prevent any intake of air, and squeezing the tube. Preferably, sections 2 and 3 of the device will be hinged to each other at the lower section 4. However, the main characteristic of the device is that the two sections 2 and 3 can be moved in relation to one another, in order to clamp and compress the inner tubular receptacle or container 1, whereby the arrangement of both sections can be variable; for example, they can be movable rectilinearly, in form of laterally hinged container and cover parts, or arranged in any other manner which achieves the required aims, i.e., that the receptacle with thin walls carrying the sample for analysis is well centred, that the liquid contained in the said tubular receptacle is collected, and also that once the integral components of the device have been adapted so as to ensure that the receptacle is ruptured and squeezed, the unit which is constructed in this manner offers fluid-tight conditions which are similar to those of a test tube, and which makes it possible for the device to be used in the later analytical stages. In order to achieve the desired objects, the device which is the subject of the present invention will comprise an internal passage 8 which will be substantially concentric with the liquid mass 6 in the lower small container 4, so as to enable the pipetting needle 7 to be inserted, and similarly the device will be provided with means for cutting the tubular element, the said means being constructed in the form of sharp points or projecting points of another type, knife components, etc. which are shown diagrammatically in the drawings and indicated by the numerals 9, 10 and 11. One of these components will cut into the tubular component near the lower end, which is designed as an outlet for the contents of the receptacle, while the other means, if they are provided, will be situated in the higher portion of the receptacle for the purpose of enabling air to be taken inside the said receptacle, in order to assist the process of emptying the same. In the case shown in Figures 1 and 2 the component 2 is provided with projecting points 9, 10 and 11 and the element or section 3 has corresponding recesses 12, 13 and 14 in order to permit the cutting components to be partially inserted into the tubular component 1 for the purpose of rupturing its walls. For the purpose of holding the two components or sections 2 and 3 of the device once the rupturing and squeezing actions have been carried out, it will be possible to provide side flaps 15 or other similar components in one of the sections, the said flaps being designed so that they can be inserted into one another as shown by numeral 16 in Figure 5, and the same effect can similarly be obtained with other fastening components ensuring that the two components are well secured to each other. Obviously, it will also be possible for the desired effect to be obtained by hinging the two sections 2 and 3 by means of an appropriate pivot 17 as shown in Figures 5 and 6. Thus, the described method will comprise a first stage of centring and axially holding the tubular element inside the rupturing and squeezing device, subsequently simultaneously rupturing transversely at a point close to the lower end of the tubular element and optionally at points which are situated in the extreme upper portion of the same and finally compressing the receptacle in order to squeeze out the liquid held inside the same, the empty tubular receptacle becoming lodged inside the device, the said device being manufactured from transparent materials in order to enable the used receptacle to act as a holder for the marks identifying the sample, thus enabling the sample to be identified both visually and automatically in an automated analytical apparatus.

Claims: A method for extracting and handling biological liquids from thin-walled tubular receptacles in which they are held, and handling the same, wherein a thin-walled tubular element is used for holding a sample of liquid, which tubular element is provided externally with identifying marks and is inserted inside a device having transparent walls, so that it is centred laterally and axially, which device is made to carry out the controlled rupturing of the receptacle at a point which is close to its lower end in order to empty the receptacle, and optionally at points which are close to its top end so as to provide for air intake, then transversely compressing the tubular element so as to squeeze the same, the tubular element being lodged securely in the rupturing and squeezing device so as to ensure that the identifying data of the sample contained in the said thin-walled receptacle can still be read. Apparatus for extracting and handling biological liquids from thin-walled tubular receptacles (1) in which they are held and handling the same, by the method according to claim 1, wherein said apparatus comprises at least two sections (2, 3) which can be joined to each other, one section being movable in relation to another, and including means for radially and axially holding the thin-walled tubular receptacle containing a sample of liquid and being provided with means whereby the two sections of the apparatus co-operate to cause the thin-walled receptacle to be ruptured at desired points, the said sections being constructed so that the thin-walled receptacle can be squeezed after the said receptacle has been ruptured, and the section (2) which directly receives the thin-walled receptacle having transparent characteristics, in order to facilitate reading from outside of identifying marks which identify the said receptacle which holds the sample to be analyzed. Apparatus according to claim 2, characterised in that both sections of the same are connected to a container-section (4) with liquid-tight properties so that it can receive the liquid to be analyzed which is held in the thin-walled receptacle. Apparatus according to claims 2 and 3, characterised in that the two connecting sections of the device and the container-section for receiving the same constitute a unit made of plastics material, whereby the two main sections of the device are hinged to each other and to the said container-section. Apparatus according to claims 2 and 3, characterised in that the said two sections are hinged to each other and one of them is integral with the container-section for receiving the liquid to be analyzed. Apparatus according to claims 2 to 5, characterised in that one of the two sections holds an axial conduit (8) affording access for a pipetting needle, which can be inserted so as to extend into the container-section. Apparatus according to claims 2 to 5, characterised in that one of the said sections is provided with cutting elements (9, 10, 11) which are capable of cutting or perforating the receptacle holding the sample to be analyzed, at the required points. Apparatus according to claim 7, characterised in that one section of the device is provided with recesses (13, 14) which co-operate with the cutting elements of the other section, for the purpose of compressing and cutting the receptacle holding the liquid to be analysed. Apparatus according to claims 2 to 8, characterised in that holding means (15, 16) are provided between the two integral sections of the device to enable them to be secured in position after they have been interengaged with one another. Apparatus according to claims 2 to 9, characterised in that the two integral sections and the said container-section can be interengaged to form a unit, the overall form of which is similar to that of a test tube.

Inventors: MARTINELL GISPER-SAUCH ENRIQUE, MARTINELL GISPER-SAUCH, ENRIQUE
Applicants: PROBITAS PHARMA SA, PROBITAS PHARMA, S.A.
Application year: 1998
Main classification: B01L3
IPC codes: G01N35, G01N1, A61B5, B01L3, G01N33, B67B7, B01L11