Abstract:
Disclosed are a blood tester for measurement of temperature of a sample placed in a blood-testing disc using a thermochromic pigment, and a control method thereof. The disclosed blood-testing disc, the blood tester having the blood-testing disc loaded therein, and the control method of the same, are used to measure a light absorbance of the thermochromic pigment in order to determine a temperature of a sample when a biological material such as blood, blood serum, blood plasma, or sputum, is subjected to analysis, so that the test may be executed at a constant temperature. Accordingly, more reproducible and accurate results are obtainable, and temperature measurement of a sample may be simply and effectively attained by an optical analyzer built in the blood tester, without an alternative instrument or sensor for measurement thereof.

Description:
CROSS-REFERENCE TO RELATED APPLICATION  
       [0001]    This application claims the benefit of Korean Patent Application No. 2009-89100 filed on Sep. 21, 2009 with the Korean Intellectual Property Office, the disclosures of which are incorporated herein by reference. 
       BACKGROUND  
       [0002]    1. Field 
         [0003]    Embodiments relate to a blood tester for measurement of temperature of a sample contained in a blood-testing disc using a thermochromic pigment, and a control method thereof. 
         [0004]    2. Description of the Related Art 
         [0005]    In general, pathogenic studies require many manual operations and various instruments to analyze biological materials including, for example, blood, blood serum, blood plasma, sputum, etc. In order to conduct an assay by a predetermined process, some stages of the process, e.g., reagent introduction, mixing, separation and migration, reaction, centrifugation, and so forth are executed by manual operation of an experimenter once or several times. 
         [0006]    Accordingly, a highly skilled clinical pathologist is required to rapidly implement an assay and such a skilled clinical pathologist also has difficulty in simultaneously conducting several tests. In particular, some assaying methods with different processes such as immunoassay or clinical chemistry require different instruments, leading to more significant difficulties in simultaneous testing. In diagnosis of emergency patients, a rapid examination and results thereof are very important for prompt emergency services. Therefore, an instrument capable of simultaneously, rapidly and correctly conducting a plurality of pathogenic examinations in relation to medical situations is required. 
         [0007]    As an example of such instruments, a blood-testing disc including a fluid storage chamber, a channel through which the fluid flows and a valve for regulating the fluid flow, has been developed in order to enable simultaneous, rapid and correct implementation of multiple pathogenic assays, e.g., immunoassay, clinical chemistry, gene study, etc. For instance, after introducing a blood sample into a rotatable blood-testing disc, the disc is rotated, thereby achieving centrifugation to separate serum from the blood sample. The separated serum is then mixed with a desired amount of diluent and transferred to several reaction chambers. Different reagents depending on blood test items are contained beforehand in the chambers and each of such reagents reacts with the serum to generate a specific color. Blood assay is performed by measuring light absorbance based on variation in color. 
         [0008]    With regard to the foregoing blood-testing disc, since reagents/samples are generally stored in a chilled state, these are generally kept at room temperature before examination, then used. In this case, a temperature of the sample depends upon a time period during which the sample is maintained at room temperature. In particular, the temperature of the sample is a very important parameter, influencing antigen-antibody reaction, substrate reaction, enzyme reaction, and the like. Therefore, the experimental conditions, including the temperature of a sample at the time of testing is significant for obtaining reproducible results during immunoassay or clinical chemistry. 
       SUMMARY  
       [0009]    The present disclosure describes a blood tester for measuring the temperature of a sample using a thermochromic pigment, where a material for analysis, such as blood, blood serum, blood plasma, or sputum may be assayed in a blood-testing disc as well as, a method for controlling the blood tester. 
         [0010]    Also, a blood tester may control the starting time of a reaction based on when the temperature of a sample reaches a preset level suitable for examination and enables the examination to be executed at a constant temperature whenever the sample is subjected to continuous/discontinuous testing and a control method thereof. 
         [0011]    According to an embodiment, a blood-testing disc may include a reaction chamber in which a reagent reacts with a sample, as well as a thermochromic pigment used for measuring a temperature of the sample. 
         [0012]    Such a thermochromic pigment may be in any form, including a powder, slurry, master batch or film. 
         [0013]    A film type thermochromic pigment may be prepared by applying a powder or liquid thermochromic pigment to a film, which is in turn attached to a blood-testing disc. 
         [0014]    A master batch type thermochromic pigment may be prepared by directly adding a pigment to a plastic resin as a raw material for a blood-testing disc. 
         [0015]    Such a plastic resin may include polyethylene (PE), polypropylene (PP), polystryrene (PS), polymethyl (meth)acrylate (PMMA), cyclic olefin copolymer (COC), acrylonitrile styrene copolymer (AS) or polyvinyl chloride (PVC). 
         [0016]    The temperature range in which the color of a thermochromic pigment may be altered is from −15 to 220° C. 
         [0017]    A concentration of the thermochromic pigment may be adjusted depending upon an optical measurement range. 
         [0018]    An optically measurable wavelength may range from 200 to 900 nm depending upon the color of the thermochromic pigment. 
         [0019]    Examples of a thermochromic pigment include spiropyrans, ethylene compounds (dixanthylene, bianthrone, xanthylideneanthrone), disulfide (diphenyldisulfide, β-dinaphthyldisulfide), or polyamide diacetylene. 
         [0020]    The thermochromic pigment may have a main color, including red, rose red, orange, yellow, sky blue, fast blue, dark blue, violet and green, and may also be prepared with other colors by combination of two or more colors. 
         [0021]    According to another embodiment a blood tester may include: a blood-testing disc containing a thermochromic pigment; an optical analyzer to measure a light absorbance of the pigment; and a control part that determines the temperature of a sample in the blood-testing disc using the measured light absorbance, determines whether the sample temperature reaches a preset level, and controls the start of assaying the blood-testing disc when the sample temperature reaches the preset level. 
         [0022]    The blood-testing disc may include a reaction chamber, in which the reagent reacts with the sample, and a pigment chamber, containing the thermochromic pigment. 
         [0023]    The optical analyzer includes: a plurality of light sources to irradiate the pigment chamber with light having different wavelengths; and a plurality of light detection devices to detect a light transmittance of the light penetrating the pigment chamber, wherein the light sources may be aligned to face the corresponding detection devices by interposing the blood-testing disc between the light sources and detection devices. 
         [0024]    The plural light sources and the plural detection devices may be arranged opposite to the reaction chamber and the pigment chamber at constant intervals. 
         [0025]    The control part may determine the sample temperature by calculating the temperature of the thermochromic pigment according to a signal detected by the light detection device. 
         [0026]    An embodiment of the blood tester may further include an identification part to recognize information about the blood-testing disc, while the control part sets a temperature of a sample suitable for immunoassay or clinical chemistry according to the information about the blood-testing disc. The identification part to recognize information may include, but is not limited to, an optical scanning device. The optical device may include a laser scanner capable of reading a bar code. 
         [0027]    The control part may determine whether the sample temperature reaches the preset temperature and, if so, may control the start of assaying the blood-testing disc. 
         [0028]    When the sample temperature is less than the preset temperature, the control part may control heating of the blood-testing disc, which in turn may enable the sample temperature to reach the preset temperature. The term “preset temperature” as used herein is defined for the purposes of the specification as “a target temperature that is selected by the experimenter and may be between −15 to 220° C.” 
         [0029]    According another embodiment a method for controlling a blood tester may include: loading a blood-testing disc containing a thermochromic pigment (into the blood tester); measuring a light absorbance of the thermochromic pigment; measuring a temperature of a sample placed in the blood-testing disc using the measured light absorbance of the thermochromic pigment; and comparing the sample temperature with the preset temperature and, when the sample temperature reaches the preset temperature, starting an assay of the blood-testing disc. 
         [0030]    The measurement of light absorbance of the thermochromic pigment may include measuring an degree or amount of variation in color of the thermochromic pigment based on optical transmission. 
         [0031]    The measurement of temperature of the sample placed in the blood-testing disc may be performed by calculating a temperature of the thermochromic pigment based on optical transmission and measuring a temperature of the sample according to the calculated temperature of the thermochromic pigment. 
         [0032]    The control method may further include: recognizing information about the blood-testing disc; and setting a temperature of a sample suitable for assay of the blood-testing disc based on the information about the blood-testing disc. 
         [0033]    The control method may further include heating of the blood-testing disc when the sample temperature is less than the preset temperature. 
         [0034]    As described above, according to the disclosed blood-testing disc, the blood tester equipped with the same and the control method thereof, assay of biological substances, such as blood, blood serum, blood plasma, sputum, etc., may start at a constant temperature by measuring a light absorbance of a thermochromic pigment and, in turn, determining a temperature of a sample, so that more reproducible and accurate results are obtainable for test items influenced by temperature as an important parameter. In addition, temperature measurement of a sample may be simply and effectively attained by an optical analyzer built in the blood tester, without an alternative instrument or sensor for measurement thereof. Moreover, an experimenter can select a desired optically measurable wavelength in consideration of use thereof, and also predetermine a temperature range, at which color is varied, in consideration of test purposes. Therefore, the disclosed embodiments may be used in a wide range of applications. The thermochromic pigment used herein may take any form including a powder, slurry, master batch or film, thus being used in a solid state as well as a liquid state in various applications. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS  
         [0035]    Hereinafter, exemplary embodiments will be described in greater detail with reference to the accompanying drawings: 
           [0036]      FIG. 1  is a view illustrating reaction characteristics of a thermochromic pigment according to an exemplary embodiment; 
           [0037]      FIG. 2  is a view illustrating an optical measurement principle of a thermochromic pigment according to an exemplary embodiment; 
           [0038]      FIGS. 3A and 3B  are graphs illustrating measured results of light absorbance of 1% blue slurry at a wavelength of 630 nm according to an exemplary embodiment; 
           [0039]      FIGS. 4A and 4B  are graphs illustrating measured results of light absorbance of light blue powders with different concentrations at a wavelength of 630 nm according to an exemplary embodiment; 
           [0040]      FIGS. 5A and 5B  are graphs illustrating measured results of light absorbance of 0.25% black powder at a wavelength of 450 nm according to another exemplary embodiment; 
           [0041]      FIG. 6  is a configuration view illustrating an example of a blood-testing disc containing a thermochromic pigment according to an exemplary embodiment; 
           [0042]      FIG. 7  is a configuration view illustrating another example of a blood-testing disc containing a thermochromic pigment according to an exemplary embodiment; 
           [0043]      FIG. 8  is a schematic configuration view illustrating a blood tester for measurement of temperature of a sample placed in a blood-testing disc using a thermochromic pigment according to an exemplary embodiment; 
           [0044]      FIG. 9  is a schematic configuration view illustrating a blood tester for measurement of temperature of a sample placed in a blood-testing disc using a thermochromic pigment according to another exemplary embodiment; 
           [0045]      FIG. 10  is a control block diagram illustrating a blood tester for measurement of temperature of a sample placed in a blood-testing disc using a thermochromic pigment according to an exemplary embodiment; and 
           [0046]      FIG. 11  is a flow diagram illustrating a process of controlling measurement of temperature of a sample placed in a blood-testing disc using a thermochromic pigment according to an exemplary embodiment. 
       
    
    
     DETAILED DESCRIPTION  
       [0047]    Hereinafter, reference will be made in detail to exemplary embodiments without particular restriction to these embodiments. 
         [0048]      FIG. 1  is a view illustrating reaction characteristics of a thermochromic pigment according to an embodiment of the present disclosure. 
         [0049]    Referring to  FIG. 1 , a thermochromic pigment  10  may be a reversible heat sensitive substance with color variation depending upon temperature, including a microcapsule consisting of an electron donor  11  and an electron acceptor  12 . 
         [0050]    The thermochromic pigment  10  may generate a color on a crystalline material by interaction between the electron donor  11  and the electron acceptor  12 , wherein, when a temperature rises (that is, at a high temperature), the electron acceptor  12  combined with the electron donor  11  is separated therefrom and loses color (becomes transparent). In contrast, when the temperature decreases, the electron acceptor  12  is again combined with the electron donor  11  such that color is generated. 
         [0051]    The thermochromic pigment  10  may have a main color including, for example, red, rose red, orange, yellow, sky blue, fast blue, dark blue, violet, green and black and, in addition, may be prepared with other colors by combination of two or more colors. 
         [0052]    Examples of materials of the thermochromic pigment  10  may include, for example: spiropyrans; ethylene compounds (e.g., dixanthylene, bianthrone, xanthylideneanthrone); disulfide (e.g., diphenyldisulfide, β-dinaphthyldisulfide); polyamide diacetylene, etc. In addition, the thermochromic pigment may take any form including a powder, slurry, master batch or film. The master batch type pigment may be prepared using a resin selected from PE, PP, PS, PMMA, cyclic olefin copolymer (COC), AS and PVC. 
         [0053]      FIG. 2  is a view illustrating an optical measurement principle of a thermochromic pigment according to an exemplary embodiment. 
         [0054]    Referring to  FIG. 2 , an optical analyzer  30  may include a light source  31  (e.g., LED) and a light detection device  32  (e.g., photodiode) that may be disposed by interposing a chamber  20  containing the thermochromic pigment  10  therebetween and may measure variation in color of the thermochromic pigment  10  by applying optical transmission. 
         [0055]    Where the light source  31  emits light to the chamber  20  containing the thermochromic pigment  10 , optical transmission, that is, light absorbance of the light penetrating the chamber  20 , is measured by the light detection device  32 . Since the measured light absorbance depends upon variation in color of the thermochromic pigment  10 , an internal temperature of the thermochromic pigment  10  may be determined by measuring the light absorbance. 
         [0056]    A temperature area in which variation in color of the thermochromic pigment  10  occurs, that is, in which a color of the thermochromic pigment is altered, may range from −15 to 220° C. and the temperature area is optionally defined within this range. 
         [0057]    The light source  31  irradiates the chamber  20  containing the thermochromic pigment  10  with light having an optically measurable wavelength in the range of 200 to 900 nm, depending upon color of the thermochromic pigment  10 . Accordingly, a concentration of the thermochromic pigment  10  may be adjustable based on the optically measurable wavelength range. 
         [0058]    According to color and concentration of the thermochromic pigment  10 , an experimenter can select and use a specific light absorbance measured at the optically measurable wavelength, in consideration of test purposes and kinds of samples. 
         [0059]      FIGS. 3A and 3B  are graphs illustrating measured results of light absorbance of 1% blue slurry at a wavelength of 630 nm according to an exemplary embodiment. 
         [0060]    In  FIG. 3A , wherein the x-axis is temperature and the y-axis is light absorbance, it was found that a 1% blue slurry comprising the thermochromic pigment  10  becomes transparent in the temperature range of 31 to 33° C., in turn exhibiting reduced light absorbance. 
         [0061]    In  FIG. 3B , a straight line for light absorbance measured in the temperature range of 31 to 33° C. is expressed by a linear equation of, e.g., y=−0.2667x+10.012. 
         [0062]    Here, a correlation coefficient R 2  for the foregoing thermochromic pigment is 0.9985, which is substantially close to 1, meaning that the light absorbance is closely correlated with the temperature. 
         [0063]    Accordingly, for the thermochromic pigment  10  in the form of 1% blue slurry, using the light absorbance measured at 630 nm in the temperature range of 31 to 33° C. may determine a temperature of a sample. Therefore, in consideration of test purposes and kinds of samples, an experimenter can select and use a specific light absorbance. 
         [0064]      FIGS. 4A and 4B  are graphs illustrating measured results of light absorbance of light blue powders with different concentrations at a wavelength of 630 nm according to an exemplary embodiment. 
         [0065]    As illustrated in  FIG. 3A , when the x-axis is temperature and the y-axis is light absorbance in  FIG. 4A , it was found that each of thermochromic pigments  10  in 3% and 3.5% light blue powders, respectively, becomes transparent in the temperature range of 26 to 28° C., in turn exhibiting reduced light absorbance. 
         [0066]    In  FIG. 4B , a straight line for light absorbance of the 3% light blue powder pigment measured in the temperature range of 26 to 28° C. is expressed by a linear equation of, e.g., y=−0.2767x+10.953, while a straight line for light absorbance of the 3.5% light blue powder pigment measure in the same temperature range is expressed by another linear equation of, e.g., y=−0.4139x+13.993. 
         [0067]    Here, a correlation coefficient R 2  for the 3% light blue powder pigment is 0.9895 and another correlation coefficient R 2  for the 3.5% light blue powder pigment is 0.9968, each of which is substantially close to 1, meaning that the foregoing pigment exhibits a close correlation between light absorbance and temperature. 
         [0068]    Accordingly, for each of thermochromic pigments  10  in the form of 3% blue powder and 3.5% blue powder, respectively, using the light absorbance measured at 630 nm in the temperature range of 26 to 28° C. may determine a temperature of a sample. Therefore, in consideration of test purposes and kinds of samples, an experimenter can select and use a specific light absorbance. 
         [0069]      FIGS. 5A and 5B  are graphs illustrating measured results of light absorbance of 0.25% black powder at a wavelength of 450 nm according to another embodiment of the present disclosure. 
         [0070]    As illustrated in  FIGS. 3A and 4A , when the x-axis is temperature and the y-axis is light absorbance in  FIG. 5A , it was found that the thermochromic pigment  10  in 0.25% black powder becomes transparent in the temperature range of 35 to 38° C., in turn exhibiting reduced light absorbance. 
         [0071]    In  FIG. 5B , a straight line for light absorbance measured in the temperature range of 35 to 38° C. is expressed by a linear equation of, e.g., y=−0.2938x+12.773. 
         [0072]    Here, a correlation coefficient R 2  is 0.998, which is substantially close to 1, meaning that the foregoing pigment exhibits a close correlation between light absorbance and temperature. 
         [0073]    Accordingly, for the thermochromic pigment  10  in the form of 0.25% black powder, using the light absorbance measured at 450 nm in the temperature range of 35 to 38° C. may determine a temperature of a sample. Therefore, in consideration of test purposes and kinds of samples, an experimenter can select and use a specific light absorbance. 
         [0074]      FIG. 6  is a configuration view illustrating an example of a blood-testing disc containing a thermochromic pigment according to an exemplary embodiment. 
         [0075]    Referring to  FIG. 6 , a blood-testing disc  100  includes a reaction chamber  110  in which a reagent reacts with a sample, and a pigment chamber  120 , which may contain a thermochromic pigment  10 . 
         [0076]    More particularly, a rotatable blood-testing disc  100  has two reaction chambers  110  spaced at an interval of 180° angle. A reagent is introduced beforehand into each of the reaction chambers  110 , thus reacting with particular ones among ingredients of a sample, in turn generating a color. Depending upon kinds of the reagent, ingredients reacting with the reagent are different and the color is also varied. 
         [0077]    Likewise, two pigment chambers  120  are disposed at an interval of 180° angle on a surface of the blood-testing disc  100 . Each of the pigment chambers  120  contains the thermochromic pigment  10  in slurry state, wherein the color of the pigment is varied according to temperature range. In particular, as illustrated in  FIGS. 3 to 5 , the thermochromic pigment  10  contained in the pigment chamber  120  may be prepared with different colors and/or concentrations according to test purposes and kinds of samples. 
         [0078]      FIG. 7  is a configuration view illustrating another example of a blood-testing disc containing a thermochromic pigment according to an exemplary embodiment. 
         [0079]    Referring to  FIG. 7 , after coating a film  121  with a thermochromic pigment  10  in powder or liquid state, the coated film is fixed and attached to a blood-testing disc  100 . Alternatively, a master batch type pigment may be prepared by directly adding a thermochromic pigment  10  to a plastic resin as a raw material of the blood-testing disc  100 . 
         [0080]    Referring to  FIGS. 6 and 7 , the blood-testing disc  100  is an illustrative example of a disc used for immunoassay. For a commonly used immunoassay disc, a reaction chamber and a detection chamber may be separately present in the disc. Since the reaction chamber is substantially positioned closer to the back of the disc than the detection chamber, a resultant product may be delivered to the detection chamber through a channel after completing reaction, followed by optical measurement thereof. In this case, the detection chamber does not contain a reagent. 
         [0081]      FIG. 8  is a schematic configuration view illustrating a blood tester for measurement of temperature of a sample placed in a blood-testing disc using a thermochromic pigment according to an exemplary embodiment. 
         [0082]    Referring to  FIG. 8 , a blood tester  200  comprises: a centrifugally rotatable blood-testing disc  100  containing a thermochromic pigment  10 ; a rotating driver  210  to rotate the blood-testing disc  100 ; an optical analyzer  220  to measure a light absorbance of the thermochromic pigment  10 ; and a control part  250  that determines a sample temperature using the light absorbance of the thermochromic pigment  10  measured by the optical analyzer  220 , and controls the start of assaying the blood-testing disc. 
         [0083]    Although a reaction chamber  110  and a pigment chamber  120  only are illustrated in  FIG. 8 , the blood-testing disc may also have other components in the center thereof, for example: a sample chamber in which a sample such as blood is stored; a dilution chamber in which another reagent such as a diluent miscible with the sample is stored; several channels connecting the foregoing chambers to one another; and/or at least one valve for control of the flow passing through the channels. More detailed description of the blood-testing disc  100  is disclosed in an earlier co-pending application of the present applicant, Korean Laid-Open Patent Application No. 10-2009-0020086, the disclosure of which is incorporated herewith by reference. 
         [0084]    If the blood-testing disc  100  with such a configuration is rotated at a high speed, the sample stored in the sample chamber flows toward an outer side of the blood-testing disc  100  via the channel by centrifugal force, so as to be blended with other reagents in turn flowing into the reaction chamber  110 . 
         [0085]    A shape of the blood-testing disc  100  is not particularly limited to a disc form and may include a sector form disc capable of being fixed to a rotatable frame, in addition to a round type rotating disc. The blood-testing disc  100  is easily formable and may be fabricated using a biologically inactive plastic material such as PMMA, polydimethyl siloxane (PDMS), polycarbonate (PC), etc. Other than the foregoing materials, the blood-testing disc may also be fabricated using any materials with desired chemical and/or biological stability, favorable optical transparency and mechanical workability, without particular restrictions thereto. 
         [0086]    Meanwhile, the rotating driver  210  provides centrifugal force to rotate the blood-testing disc  100  at a high velocity, so as to enable the sample to be introduced into the reaction chamber  110  mounted on the blood-testing disc  100 . Also, according to rotation of the blood-testing disc  100 , the rotating driver  210  guides the reaction chamber  110  and the pigment chamber  120  to face the optical analyzer  220 . 
         [0087]    The optical analyzer  220  comprises a plurality of, e.g., ten (10) light sources  230  (e.g., LED) which are disposed on a bottom of the blood-testing disc  100  equipped with the reaction chamber  110  and the pigment chamber  120 , as well as a plurality of, e.g., 10 light detection devices  240  (e.g., photodiode) which are disposed on a top of the same blood-testing disc  100 . An optical measurement device provided in a conventional blood tester is used as the optical analyzer  220 . 
         [0088]    The plural light sources  230  are aligned opposite to the reaction chamber  110  and the pigment chamber  120  on the blood-testing disc  100  at constant intervals. Likewise, the plural light detection devices  240  are also aligned opposite to the reaction chamber  110  and the pigment chamber  120  on the blood-testing disc  100  at constant intervals. Each of the light sources  230  is arranged to face each corresponding light detection device  240  such that ten (10) different wavelengths are all determined in each of the chambers  110  or  120  during rotation of the blood-testing disc  100 . 
         [0089]    The plural light sources  230  emit light having an optically measurable wavelength (200 to 900 nm) to the pigment chamber  120  containing the thermochromic pigment  10  depending upon color thereof and the measurable wavelength may be selected by an experimenter in consideration of use thereof. While measuring a light absorbance using one of the light sources  230 , the remaining light sources  230  are shut off in order to prevent errors during measurement of the light absorbance. 
         [0090]    When light having different wavelengths irradiates the pigment chamber  120  containing the thermochromic pigment  10 , optical transmission, e.g., a light absorbance of the light penetrating the pigment chamber  120  is measured in the plural light detection devices  240 . Since the light absorbance measured in the plural light detection devices  240  is altered depending upon variation in color of the thermochromic pigment  10 , an internal temperature of the thermochromic pigment  10  may be determined by measuring the light absorbance. 
         [0091]    The control part  250  functions to control behavior of the rotating driver  210  and the optical analyzer  220 . More particularly, the control part detects a rotation phase of the rotating driver  210  and, through rotation phase synchronization, controls measurement of light absorbance of the reaction chamber  110  or the pigment chamber  120  in the optical analyzer  220 . For instance, the blood-testing disc  100  has a mark indicating a reference position and controls behavior of the optical analyzer  220  to enable measurement of light absorbance at a site facing the reaction chamber  110  or the pigment chamber  120  using a rotational speed of the disc  100 . 
         [0092]    The control part  250  measures a light absorbance of the thermochromic pigment  10  penetrating the pigment chamber  12  according to a signal detected by the light detection device  240  of the optical analyzer  220 , in turn, calculates an internal temperature of the thermochromic pigment  10  and determines a temperature of a sample using the calculated temperature of the thermochromic pigment  10 . 
         [0093]    With the measured temperature of the sample according to the light absorbance of the thermochromic pigment  10 , the control part  250  determines whether the sample temperature is a preset temperature (e.g., 37° C.) suitable for immunoassay and, if the sample temperature is less than the preset temperature, commands heating of the blood-testing disc  100 , and then, controls the start of the immunoassay when the sample temperature reaches the preset temperature. Since the control part  250  has a sample temperature predetermined for immunoassay and stored therein, a sample is taken out from a refrigerator and introduced into the sample chamber built in the blood-testing disc  100 , followed by measuring a light absorbance of the thermochromic pigment  10  during rotation of the blood-testing disc  100  in order to execute immunoassay. As a result of measuring the light absorbance and, in turn, determining the sample temperature, the control part controls the start of the immunoassay if the sample temperature reaches a preset level suitable for immunoassay, thereby enabling the start of reaction under a constant temperature condition. 
         [0094]      FIG. 9  is a schematic configuration view illustrating a blood tester for measurement of a temperature of a sample placed in a blood-testing disc using a thermochromic pigment, according to another exemplary embodiment. The constitutional components substantially the same as those of  FIG. 8  are represented by the same reference numerals and detailed descriptions thereof will be omitted hereinafter to avoid repetition where it may make the subject matter of the disclosure less clear. 
         [0095]    Referring to  FIG. 9 , a blood tester  200  comprises: a rotatable blood-testing disc  300  containing a thermochromic pigment  10 ; a rotating driver  210  to rotate the blood-testing disc  300 ; an optical analyzer  220  to measure a light absorbance of the thermochromic pigment  10 ; and a control part  250  that determines a sample temperature using the light absorbance of the thermochromic pigment  10  measured by the optical analyzer  220 , and then, controls the start of assaying the blood-testing disc  300  at a certain temperature. 
         [0096]    While two reaction chambers  110  illustrated in  FIG. 8  are disposed and spaced from each other at an interval of 180° angle on a top of the rotatable blood-testing disc  100 ,  FIG. 9  shows that a plurality of (i.e., at least 18 units) reaction chambers  310  is arranged at constant intervals on the same radial positions from a top of the blood-testing disc  300 . In terms of test items, the reaction chambers contain different type reagents, respectively, provided beforehand therein. Each of such reagents in the reaction chambers  310  reacts with a specific ingredient contained in a sample to generate a color. Reactive materials may depend on kinds of the reagents and may generate different colors. 
         [0097]    The blood-testing disc  300  illustrated in  FIG. 9  is an example of common discs used for clinical chemistry. Two pigment chambers  310  containing the thermochromic pigment  10  are disposed and spaced from each other at an interval of 180° C. angle on a top of the blood-testing disc  300 , which is the same as illustrated in  FIG. 8 . 
         [0098]    Accordingly, with the measured temperature of the sample according to the light absorbance of the thermochromic pigment  10 , the control part  250  determines whether the sample temperature is a preset temperature (e.g., 25° C., 30° C., 37° C. . . . ) suitable for clinical chemistry and, if the sample temperature is less than the preset temperature, commands heating of the blood-testing disc  300 , and then, controls the start of the clinical chemistry when the sample temperature reaches the preset temperature. Since the control part  250  has a sample temperature predetermined for clinical chemistry and stored therein, a sample is removed from a refrigerator and introduced into the sample chamber built in the blood-testing disc  300 , followed by measuring a light absorbance of the thermochromic pigment  10  during rotation of the blood-testing disc  300  in order to execute clinical chemistry. As a result of measuring the light absorbance and, in turn, determining the sample temperature, the control part controls the start of the clinical chemistry if the sample temperature reaches a preset level suitable for clinical chemistry, thereby enabling the start of reaction under a constant temperature condition. 
         [0099]      FIG. 10  is a control block diagram illustrating a control process of a blood tester for measurement of temperature of a sample placed in a blood-testing disc using a thermochromic pigment, according to an exemplary embodiment. In this drawing, an identification part  260 , a storage part  270  and a heating part  280  are further illustrated in addition of configurations shown in  FIGS. 8 and 9 . 
         [0100]    When the blood-testing disc containing the thermochromic pigment  10  is safely placed on a tray of the blood tester  200 , and then, loaded in the blood tester, the identification part  260  recognizes information about the blood-testing disc (e.g., an immunoassay disc or a clinical chemistry disc) and transfers the recognized information to the control part  250 . 
         [0101]    The storage part  270  provides a database file corresponding to the information about the blood-testing disc  100  or  300  recognized in the identification part  260 , to the control part  250 . According to the information, the control part  250  controls an optical reaction in the blood-testing disc  100  or  300 . For example, after determining whether the blood-testing disc  100  or  300  is an immunoassay disc or a clinical chemistry disc, a specific sample temperature suitable for each of the foregoing testing manners is stored in the control part  250  according to the determined results. 
         [0102]    When it is determined whether the sample temperature determined in the control part  250  using the light absorbance of the thermochromic pigment  10  is a preset temperature suitable for immunoassay or clinical chemistry, then, if the sample temperature is less than the preset temperature, the heating part  280  heats the blood-testing disc  100  or  300  according to control commands of the control part  250 . The heating part  280  is arranged above and below the tray on which the blood-testing disc  100  or  300  is safely placed, thus heating both sides of the blood-testing disc  100  or  300 . 
         [0103]      FIG. 11  is a flow diagram illustrating a control process of measuring a sample temperature in a blood tester for measurement of temperature of a sample placed in a blood-testing disc using a thermothromic pigment, according to an exemplary embodiment. 
         [0104]    Referring to  FIG. 11 , in order to execute immunoassay or clinical chemistry, a sample is first removed from a refrigerator and introduced into a sample chamber of the blood-testing disc  100  or  300 . After the blood-testing disc  100  or  300  having the sample is safely placed on a tray of the blood tester  200 , an identification part  260  recognizes information about the blood-testing disc  100  or  300  (e.g., an immunoassay disc or a clinical chemistry disc) and transfers the recognized information to the control part  250  ( 400 ). 
         [0105]    Therefore, the control part  250  receives a database file corresponding to the information about the blood-testing disc  100  or  300  recognized in the identification part  260 , from the storage part  270 , and then, controls an optical reaction in the blood-testing disc  100  or  300  ( 402 ). 
         [0106]    Afterward, the control part  250  controls a high speed rotation of the blood-testing disc  100  or  300  via the rotating driver  210 , based on the database file information (i.e., temperature information of a sample suitable for immunoassay or clinical chemistry) ( 404 ). 
         [0107]    When the blood-testing disc  100  or  300  is rotated at a high speed, the optical analyzer  220  mounted on a top and a bottom of the blood-testing disc  100  or  300  measures optical transmission, that is, a light absorbance of light penetrating the pigment chamber  120  or  320  containing the thermochromic pigment  100  and transfers the measured light absorbance to the control part  250  ( 406 ). 
         [0108]    Since the light absorbance measured in the optical analyzer  220  is altered according to variation in color of the thermochromic pigment  10 , an internal temperature of the thermochromic pigment  10  may be calculated by measuring the light absorbance. 
         [0109]    Before controlling an optical reaction in the blood-testing disc  100  or  300 , the control part  250  calculates the internal temperature of the thermochromic pigment  10  using the light absorbance measured by the optical analyzer  220  and a temperature of a sample is determined using the calculated temperature of the thermochromic pigment  100  ( 408 ). 
         [0110]    As illustrated in  FIGS. 3 to 5 , the light absorbance of the thermochromic pigment  100  is substantially coincided with a temperature of the same pigment to show a close correlation therebetween. Also, since the temperature of the thermochromic pigment  10  corresponds to a temperature of a sample, the sample temperature may be obtained by measuring the light absorbance of the thermochromic pigment  100 . 
         [0111]    Accordingly, the control part  250  determines whether the sample temperature measured by the optical analyzer  220  reaches a preset temperature suitable for assaying the blood-testing disc  100  or  300  ( 410 ). 
         [0112]    As a result of the determination in step  410 , if the sample temperature does not reach the preset temperature, the control part  250  controls the heating part  280  to heat both sides of the blood-testing disc  100  or  300  ( 412 ), then, returns to step  406  in order to execute further processes. 
         [0113]    Alternatively, as a result of the determination in step  410 , when the sample temperature reaches the preset temperature, the control part  250  controls the start of immunoassay or clinical chemistry for the blood-testing disc  100  or  300 , so as to enable the start of reaction under the same temperature condition ( 414 ). 
         [0114]    Finally, the control part  250  determines whether the assay of the blood-testing disc  100  or  300  is terminated or not ( 416 ) and, if yes, the assay of the blood-testing disc is ended. 
         [0115]    Although a few embodiments of the present disclosure have been shown and described, it would be appreciated by those skilled in the art that substitutions, variations and/or modifications may be made in these embodiments without departing from the principles and spirit of the disclosure, the scope of which is defined in the claims and their equivalents.