Abstract:
A cuvette ( 10 ) for storing a biological sample to be analyzed by means of a predefined detection technique is disclosed. The cuvette ( 10 ) is formed from a moldable material that contains particles ( 15   a   , 15   b ) at a concentration within a predefined range. The particles ( 15   a   , 15   b ) are randomly distributed, in order to form a unique pattern. Moreover, the particles ( 15   a   , 15   b ) have measurable physical properties, so that the unique pattern is detectable using the detection technique that is used to analyze the biological sample. The unique properties obtained by the randomly distributed particles ( 15   a   , 15   b ) render copying nearly impossible, since it is more complicated to distribute the particles in a predetermined pattern than to let them distribute randomly.

Description:
TECHNICAL FIELD 
       [0001]    The present invention relates to a cuvette for storing a biological sample to be analyzed by a measuring device. The invention also relates to a method for authentication of a cuvette. 
       BACKGROUND OF THE INVENTION 
       [0002]    In health care today an increasing amount of analysis of biological samples are performed instantly at the point of care due to for example developed techniques in this area. The increasing use of biological analysis causes usage of an increased amount of disposable cuvettes on which a biological sample, such as a blood sample, is stored. When performing the analysis the cuvette is introduced to a measuring device that generates an analysis result. 
         [0003]    Low cost producers have noticed that the profit is made through selling such disposable cuvettes, rather than selling the actual measuring device to which a cuvette is introduced, whereby copying of cuvettes by low cost producers has become a problem. Cuvettes being produced by low cost producers impacts on the quality of cuvettes that leads to decreased reliability of analysis results when the copied cuvettes are used in measuring devices intended for the original cuvettes. 
         [0004]    In an attempt to give a unique identity to a known cuvette it could be labeled with an identifier, such as a bar code. However, labeling requires additional steps in the manufacturing process and such a label is moreover relatively easy to reproduce. Therefore, there is a need for a cuvette that cannot be easily reproduced to thereby obtain reliable test results and that can be easily authenticated to its corresponding measuring device. 
       SUMMARY OF THE INVENTION 
       [0005]    In view of the above mentioned need, a general object of the present invention is to provide a cuvette that cannot be easily reproduced, and which is adapted to be authenticated. This and other objects are achieved through a cuvette for storing a biological sample to be analyzed by means of a predefined detection technique, the cuvette being formed from a moldable material, such as a plastic material, containing particles at a concentration within a predefined range. The particles are randomly distributed, in order to form a unique pattern, and the particles have measurable physical properties, so that the unique pattern is detectable using the detection technique. 
         [0006]    The unique pattern of the present invention is used as an identifier of the cuvette, and is integrated in the material from which the cuvette is formed, by means of randomly distributed particles. The unique properties obtained by the randomly distributed particles render copying nearly impossible, since it is more complicated to distribute the particles in a predetermined pattern than to let them distribute randomly. 
         [0007]    Furthermore, the physical properties of the particles being measurable renders the unique pattern detectable, and by that means each cuvette holds a unique detectable identity. In addition, the pattern being detectable using the same detection technique as for detecting the biological sample forms a basis for a simple authentication of the cuvette using the same technique as when analyzing the biological sample. In other words, the cuvette of the present invention is less laborious to give the unique properties to, more complicated to copy than cuvettes of prior art, and adapted to easily be authenticated without requiring additional equipment. 
         [0008]    The cuvette may moreover have a handle portion and an introducible portion adapted to be introduced into a measuring device, at least a portion of the introducible portion being a sample holding portion for storing of a biological sample, wherein the unique pattern is comprised in the introducible portion outside the sample holding portion with the result that the unique pattern may be introduced to a measuring device together with the biological sample. The unique pattern being separated from the sample holding portion forms a basis for a correct analysis result as well as a correctly executed authentication of the cuvette. 
         [0009]    Further, the size of the particles may be in the order of micrometers, preferably ranging from 1 to 10 micrometers, such as micro beads, having the properties to be easily detected by detection techniques used for sample analysis. Furthermore, the particles may have such properties so that they easily distribute in the moldable material, which hence simplifies the manufacturing process, and the achievement of the unique pattern. An example of particle material is glass. 
         [0010]    The cuvette may be provided with a readable label, wherein the label contains a stored digital representation of the unique pattern, which forms a basis for a reliable authentication of the cuvette, where the stored digital representation may be compared to the unique pattern of the cuvette. 
         [0011]    The label may be readable using the same detection technique. In this case, the label is preferably arranged adjacent to the unique pattern, so that only one image is enough to both read the label and detect the unique pattern. 
         [0012]    Further, the physical properties may be at least one of reflectivity and transmittivity, in which case the detection technique may be optical detection of an image. This is a suitable technique for obtaining a representation of the unique pattern and to read the stored representation of the label, which technique is also a common technique for analyzing a biological sample. Other detection techniques include for example chemical analysis. 
         [0013]    According to a second aspect of the present invention there is provided a method for manufacturing a cuvette for storing a biological sample to be analyzed by means of a predefined detection technique. The method comprises the steps of providing a moldable material containing particles at a concentration within a predefined range, which particles have measurable physical properties; and forming a cuvette from the material, so that the particles are randomly distributed, in order to form a unique pattern, which is detectable using the detection technique. 
         [0014]    Providing the particles constituting the unique properties already in the manufacturing process is a relatively simple way to achieve unique properties, since it belongs to the nature of such particles, such as micro beams, to distribute randomly in the moldable material. Moreover, as described in relation to the cuvette according to the present invention copying such a cuvette is nearly impossible, since it is much more complicated to manufacture a cuvette by inserting particles in a predetermined pattern, than to let them distribute randomly. 
         [0015]    According to a third aspect of the present invention, there is provided a method for authenticating a cuvette formed from a moldable material comprising particles having measurable physical properties, the particles being randomly distributed, in order to form a unique, detectable pattern. The method comprises the steps of introducing the cuvette into a measuring device that is intended to analyze a biological sample, such as a blood sample; and detecting the unique pattern of the cuvette using the measuring device. 
         [0016]    Re-using a measuring device that is intended for performing an analysis of a biological sample for also detecting the unique pattern of the cuvette is efficient and practical. No additional detection device is hence required for this purpose, and the effect of with certainty preventing usage of copied products in a measuring device is obtained. 
         [0017]    When the cuvette is provided with a label comprising a stored digital representation of the unique pattern the method may further comprise the steps of reading the stored digital representation from the label to be verified; and comparing the stored digital representation with the detected unique pattern to thereby achieve a reliable result of authentication. 
         [0018]    Moreover, the label may be readable using equipment used to detect the unique pattern, so as to be readable by the measuring device. In this case, the label is preferably provided adjacent to the unique pattern, so that only one image is enough to both read the label and detect the unique pattern. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0019]    In the following, embodiments of the present invention will be described in detail, with reference to the accompanying, exemplifying drawings on which: 
           [0020]      FIG. 1  is a perspective view of a cuvette and a measuring device according to the present invention. 
           [0021]      FIG. 2  is a perspective view of a system for analyzing a biological sample and for authenticating a cuvette. 
           [0022]      FIG. 3  is a flow chart schematically illustrating an exemplary method for analyzing a biological sample of the present invention. 
           [0023]      FIG. 4  is a flow chart schematically illustrating an exemplary method for authenticating a cuvette performed by the measuring device. 
       
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
       [0024]    The present invention will be mainly described hereinafter with reference to a cuvette  10  illustrated in  FIG. 1 . 
         [0025]    The cuvette  10  is formed from a moldable material, e.g. a plastic material, that comprises particles  15   a - b , such as glass micro beads, that are randomly distributed in the moldable material before the cuvette  10  is molded. The properties of the particles  15   a - b  are moreover measurable. 
         [0026]    The cuvette  10  comprises a handle portion  11  and an introducible portion  12 . The handle portion  11  of the cuvette  10  is adapted to be held by a user when storing a blood sample from a patient, and for simplifying insertion of the introducible portion  12  of the cuvette  10  into a measuring device. The introducible portion  12  of the cuvette  10  is further divided into a sample holding portion  13 , where the blood sample is stored, and an authentication portion  14 , adapted to uniquely identify the cuvette  10 , by the properties achieved by particles  15   a - b . The particles  15   a - b  form a unique pattern due to the unique location and orientation in relation to each other of these particles  15   a - b  for each cuvette  10 . Since the properties of the particles  15   a - b  are measurable the unique pattern may be both detected and stored, for example by means of taking an image of the pattern. The unique pattern of the authentication portion  14  of the cuvette  10  is as mentioned dedicated for the purpose of identifying the cuvette. 
         [0027]    There is a label  16  provided on the cuvette, that contains a stored digital representation of the unique pattern of the cuvette, and alternatively also a digital signature. In more detail the label may for example have been produced by first taking an image of the authentication portion  14  of the unique pattern, which image has been transformed into a compact digital representation. The signature has then been generated from the digital representation for example by means of using a signing algorithm. Signing may be performed by using for example a private key of a certification authority. The digital representation and the digital signature has thereafter been combined into so called enrolment data, which is printed or otherwise provided as a label  16  on the cuvette  10 , in the form of for example a bar code, a block code, or an electronic identifier, such as an RFID. Alternatively, the digital representation is stored e.g. in a database in the device that performs the authentication method. 
         [0028]    By digitally signing the digital representation it is more difficult for a malicious party to generate valid data, since it also requires a valid signature. 
         [0029]    In  FIG. 2  a system for analyzing a blood sample that is stored on the cuvette and for authenticating the cuvette is illustrated. The system comprises a measuring device  20  intended to perform blood sample analysis, an authentication device  30  connected to the measuring device  20 , and a reader  40  connected to the authentication device  30 . 
         [0030]    The measuring device  20  has a display  21  for displaying analysis data etc, and an opening  22  in which the cuvette  10  may be inserted. The measuring device  20  is intended for analyzing a blood sample, which is achieved through image detection techniques. As an alternative to optical detection of an image, the detection may be based on for example electrical or chemical techniques. In operation the cuvette  10  is inserted to the measuring device  20 , whereby the unique pattern of the authentication portion  14  may be detected and the blood sample which is stored on the sample holding portion  13  of the cuvette  10  may be analyzed using the same detection technique, performed by the measuring device  20 . 
         [0031]    The reader  40  is adapted to read the label of the cuvette  10 , and depending on the type of label  16 , the reader  40  may be for example a bar code reader or a block code reader. 
         [0032]    The authentication device  30  is arranged to receive data which is read by the reader  40  and to authenticate the cuvette  10  using this information, which is further described in relation to  FIGS. 3 and 4 . The authentication device  30  may be a micro processor. 
         [0033]    Alternatively the reader  40  and the authentication device  30  are part of the measuring device. 
         [0034]    An example of a method for analyzing a biological sample, here a blood sample, will now be described with reference to  FIG. 3  which is a flow chart schematically illustrating such a method. 
         [0035]    First, in step  301 , a blood sample is taken from a patient at a point of care, and is stored at the sample holding portion of the cuvette  10 . Thereafter, in step  302 , the cuvette  10  is inserted to the opening  22  of the measuring device  20 . 
         [0036]    In step  303  the cuvette is authenticated by means of an authentication method that will be further described with reference to  FIG. 4 . If the authentication is successful, meaning that the cuvette  10  is an original cuvette that is to be used in the measuring device  20  in question, step  204  is performed. 
         [0037]    In step  304  the blood sample is analyzed according to conventional methods performed by the measuring device  20 . 
         [0038]    An example of a method for authenticating a cuvette will now be described with reference to  FIG. 4  which is a flow chart schematically illustrating such a method. The method may be implemented in the authentication device  30  by storing computer program code portions in the device  30 , a processor controlling the method described hereinafter 
         [0039]    First, in step  401 , the reader  40  reads the label  16  provided on the cuvette  10 . 
         [0040]    The digital signature and the digital representation are transmitted to the authentication device  30 . Thereafter, in step  402 , the authentication device  30  verifies the digital signature comprised in the label  16 . The verification is performed by using the public key corresponding to the private key used when producing the digital signature. Only if this verification is valid, the next step  403  is performed, otherwise the program control proceeds to step  405 , waiting for next cuvette to be verified. 
         [0041]    In step  403 , after a valid verification of the digital signature and the cuvette has been inserted into the measuring device  20 , the unique pattern is detected for example by means of taking an image of the pattern from a designated authentication portion  14  outside the sample holding portion of the cuvette  10 . A representation of the detected unique pattern is transmitted to the authentication device. 
         [0042]    Next, in step  404 , the digital representation that was read from the label  16  in step  301  is compared to the detected unique pattern, by the authentication device  30 . If the consistency between these two is not sufficient the cuvette  10  is considered to be fake, and is not compatible with the measuring device  20  in question. 
         [0043]    In case there is no digital signature the steps concerning the digital signature may accordingly be left out of the method. 
         [0044]    Step  401  and  403  of reading the label  16  and detecting the unique pattern may moreover be executed at the same time, by the measuring device  20 , if the properties of the cuvette  10  allow that the same technique is used for both reading the label and detecting the unique pattern, for example by taking an image using a microscope. This may be achieved by using a photoactive dye inside the cuvette  10  which can be modified with a laser. Moreover, it requires that the label  16  and the unique pattern  14  be arranged adjacent to each other. 
         [0045]    The person skilled in the art realizes that the present invention is not limited to the preferred embodiments. For example the particle properties may be of any measurable kind, such as intensity, or color, the unique pattern may be measured by various detection techniques and combinations of these, such as only reflective measurements, or both reflective and transmission measurements, etc. 
         [0046]    Such and other obvious modifications must be considered to be within the scope of the present invention, as it is defined by the appended claims. It should be noted that the above-mentioned embodiments illustrate rather than limit the invention, and that those skilled in the art will be able to design many alternative embodiments without departing from the scope of the appended claims. In the claims, any reference signs placed between parentheses shall not be construed as limiting to the claim. The word “comprising” does not exclude the presence of other elements or steps than those listed in the claim. The word “a” or “an” preceding an element does not exclude the presence of a plurality of such elements. Further, a single unit may perform the functions of several means recited in the claims.