Analysis device

Abstract

This analysis device comprises: a photometric unit that includes a plurality of types of light-emitting elements that selectively irradiate a reaction region of an analysis chip with light having a different center wavelength and that are disposed at different positions, and an area sensor that captures an image of a predetermined imaging range including a reaction region irradiated with light from the light-emitting element; a color plate disposed within the imaging range; and a processor that calculates the concentration of the detection target substance on the basis of a measurement value corresponding to the luminance data of the reaction region extracted from the acquired image, the processor extracting, from the image, correction luminance data that is luminance data of the color plate in addition to the luminance data of the reaction region, and correcting the measurement value with the correction luminance data, wherein the processor changes an extraction region of the correction luminance data extracted from the image according to the type of the light-emitting element that emits light.

Description

Analyzer

[0001] The present disclosure relates to an analytical device.

[0002] There is known an analytical device that analyzes a specimen sample using an analytical chip onto which the specimen sample is deposited. The analysis of the specimen sample involves measuring the concentration of a detection target substance contained in the specimen sample by measuring the reaction state between the specimen sample and a reagent. The specimen sample is, for example, blood or urine. The analytical chip is generally an analytical chip equipped with a reaction region containing a dry reagent.

[0003] In the analytical device, a measurement light is irradiated onto the reaction area of ​​the analytical chip where the specimen sample has been dropped, and the reflected light is detected to detect the reaction product produced by the reaction between the substance to be detected and the reagent. For this reason, the analytical device is equipped with a photometric unit that irradiates the analytical chip with measurement light and detects the reflected light.

[0004] Japanese Patent Application Laid-Open No. 07-005110 proposes that in an analytical device, a standard reflective piece is placed within the field of view of a detector, and the reflectance of the test piece is corrected by the reflectance of the reflective piece, thereby correcting fluctuations in sensitivity due to fluctuations in the light intensity of a light source lamp, etc.

[0005] In order to perform analysis of multiple items (detection target substances), the analyzer irradiates light of a wavelength appropriate for each item. The light source may be a single white light source and an optical filter that allows wavelength selection, or may be multiple types of light-emitting elements that output light of different wavelengths.

[0006] When an analytical device is equipped with multiple types of light-emitting elements, the light-emitting elements will naturally be arranged in different positions. The light intensity distribution of light emitted by light-emitting elements arranged in different positions will not be the same, and will vary depending on the respective arrangement positions. JP-A-07-005110 does not take into consideration the fact that differences in light intensity distribution will occur depending on the arrangement of multiple types of light-emitting elements arranged in different positions when correcting for sensitivity fluctuations.

[0007] The technology of the present disclosure has been made in consideration of the above circumstances, and aims to provide an analysis device that is capable of highly accurate analysis even when equipped with multiple types of light-emitting elements.

[0008] The analytical device of the present disclosure is an analytical device that has an analytical chip with a reaction area that holds a reagent removably mounted thereon, and that analyzes a specimen sample that has been dropped onto the reaction area of ​​the analytical chip, and that includes the reagent; a photometric unit that optically detects the color produced by the reaction of a substance to be detected in the specimen sample, the photometric unit including multiple types of light-emitting elements that selectively irradiate the reaction area with light of different center wavelengths and are arranged at different positions, and an area sensor that captures an image of a predetermined shooting range that includes the reaction area irradiated with light from the light-emitting elements; a color plate that is arranged within the shooting range and has an area that is irradiated with light from all of the multiple types of light-emitting elements; and a processor that acquires an image from the photometric unit and calculates the concentration of the substance to be detected based on a measurement value corresponding to the luminance data of the reaction area extracted from the acquired image, the processor extracting correction luminance data, which is the luminance data of the color plate, from the image in addition to the luminance data of the reaction area, and correcting the measurement value with the correction luminance data, and that is configured to change the extraction area of ​​the correction luminance data extracted from the image depending on the type of light-emitting element that emits light.

[0009] The analytical chip preferably contains a dry reagent as the reagent.

[0010] It is preferable that the optical density of the color plate is 1.5 or less.

[0011] The color plate is preferably monochromatic.

[0012] According to the analysis device of the technology of the present disclosure, even when multiple types of light-emitting elements are provided, highly accurate analysis is possible.

[0013] 1 is a schematic diagram showing the overall configuration of an analysis device of an embodiment; FIG. 2 is a plan view of the main parts of the analysis device of FIG. 1; FIG. 3 is a cross-sectional view of the transport path portion of the analysis chip; FIG. 4 is a diagram showing an example of the configuration of the analysis chip; FIG. 5 is a schematic diagram showing the general configuration of the photometric unit and the positional relationship of the analysis chip; FIG. 6 is a perspective view showing the positional relationship of the analysis chip, a first group of light-emitting elements, a second group of light-emitting elements, and an area sensor; FIG. 7 is a plan view of the irradiation device and the area sensor viewed from the rotating substrate side; FIG. 8 is an image captured by the area sensor; FIG. 9 is a graph showing the variation in measurement values ​​not corrected with luminance data of a color plate in multiple measurements (comparative example); FIG. 10 is a graph showing the variation in measurement values ​​after correction with luminance data of a color plate in multiple measurements (example).

[0014] Preferred embodiments of the present invention will now be described with reference to the drawings. The same components are designated by the same reference numerals in each drawing. Fig. 1 is a schematic diagram showing the overall configuration of an analytical device 100 according to one embodiment. Fig. 2 is a plan view of the essential parts of the analytical device 100 shown in Fig. 1, Fig. 3 is a cross-sectional view of the transport path of an analytical chip, and Fig. 4 is a diagram showing an example of the configuration of an analytical chip.

[0015] The analytical device 100 shown in Fig. 1 is an example of an analytical device for analyzing a specimen sample. An analytical chip 12 is removably mounted in the analytical device 100. The analytical device 100 uses, for example, a dry analytical chip to measure the concentration of a detection target substance contained in the specimen sample. The analytical device 100 of this example uses blood as the specimen sample and optically measures the concentration of the detection target substance contained in the blood. More specifically, the concentration of the detection target substance is measured by colorimetric measurement.

[0016] The analyzer 100 comprises a chip setting section 10 , a reader 20 , a sample application section 30 , a chip transport mechanism 40 , a sample application mechanism 50 , an incubator 60 , a photometric unit 70 , a chip disposal mechanism 80 , and a processor 90 .

[0017] In the chip setting section 10, a stocker 14 for storing analytical chips 12 is arranged on a holder 11. The stocker 14 stores a plurality of analytical chips 12 in a stacked manner.

[0018] The reader 20 is, for example, a code reader that reads the item information attached to the analytical chip 12. This allows the type and / or lot number of the analytical chip 12 to be identified. The reader 20 is configured with an image sensor such as a CCD (Charge Coupled Device) or a CMOS (Complementary Metal Oxide Semiconductor). The item information read by the reader 20 is output to the processor 90.

[0019] In the specimen application section 30, a specimen sample containing a specimen such as plasma, whole blood, serum, or urine is applied to the analytical chip 12. A chip support table 31 is provided in the specimen application section 30, and the specimen sample is applied to the analytical chip 12 transported onto the chip support table 31 on the chip support table 31. The specimen sample is applied by a specimen application mechanism 50, which will be described later. The chip support table 31 is disposed adjacent to the holder table 11.

[0020] 1 and 2 , the chip transport mechanism 40 transports the analytical chip 12 from the chip setting unit 10 to the specimen application unit 30, and then from the specimen application unit 30 to the incubator 60. The chip transport mechanism 40 includes a thin plate-shaped chip transport member 42 and a drive mechanism 44 that reciprocates the chip transport member 42 in the direction in which the chip setting unit 10, the specimen application unit 30, and the incubator 60 are aligned. The drive mechanism 44 is, for example, a linear actuator. The chip transport member 42 is slidably supported by a guide rod (not shown) and is reciprocated by the drive mechanism 44.

[0021] 1 , the specimen application mechanism 50 includes a nozzle 52, a suction / discharge mechanism (not shown), and a movement mechanism for moving the nozzle 52. The specimen application mechanism 50 aspirates a specimen sample from a specimen storage section (not shown), and applies the specimen sample to the analysis chip 12 in the specimen application section 30.

[0022] The incubator 60 can accommodate multiple analytical chips 12. The incubator 60 has a thermostatic function that maintains a constant temperature to promote the reaction between the reagents in the analytical chips 12 and the specimen samples. The set temperature is, for example, 37°C.

[0023] As shown in Fig. 2, the incubator 60 includes a circular rotating platform 62 on which are provided a plurality of cells S into which analytical chips 12 are loaded. Also, on the upper part of the rotating platform 62, a disk-shaped holding member 65 having a pressing member 64 that presses the analytical chips 12 loaded in the cells S from a direction facing the reaction region 12A (see Fig. 4) is provided. The pressing member 64 is provided corresponding to each of the plurality of cells S, and as shown in Fig. 3, in the incubator 60, a slit-like space is formed between the pressing surface 64A of the pressing member 64 and the cell S, and the analytical chip 12 is loaded into this space.

[0024] A rotating cylinder 66 is provided below the rotating platform 62. The rotating cylinder 66 has a cross-sectional shape that is approximately an inverted triangle, with the inner diameter tapering downward. A bearing 67 is disposed at the bottom of the outer periphery of the rotating cylinder 66, and the rotating cylinder 66 is rotatably supported by the bearing 67. The rotating platform 62 rotates as the rotating cylinder 66 rotates. The holding member 65 rotates integrally with the rotating platform 62. The rotating cylinder 66 has an opening at the bottom, which is the apex of the inverted triangle, and this opening functions as a disposal hole 68 for disposing of used analytical chips 12. The used analytical chips 12 loaded in the cell S are moved toward the center of the annular rotating platform 62 and dropped toward the inclined surface of the rotating cylinder 66. The used analytical chips 12 that fall into the rotating cylinder 66 slide down the inclined surface and are discarded through the disposal hole 68.

[0025] The holding member 65 is provided with a heating means such as a heater (not shown), and the temperature of the analytical chip 12 housed in the cell S is maintained at a predetermined constant temperature by adjusting the temperature. A heat-retaining cover 69 is provided on the upper surface of the holding member 65. Note that Fig. 2 shows the state in which the holding member 65 and heat-retaining cover 69 have been removed, exposing the rotating platform 62.

[0026] As shown in Figure 2, a photometric opening window 62A is formed in the center of the bottom surface of each cell S of the rotating substrate 62, and colorimetric measurement of the analysis chip 12 is performed through this opening window 62A by a photometric unit 70 arranged below the rotating substrate 62.

[0027] The photometric unit 70 performs colorimetric measurement, which is measurement of the optical density of the analytical chip 12 using colorimetry. The photometric unit 70 is provided below the rotating platform 62 in the outer periphery of the incubator 60. The photometric unit 70 acquires a detection signal representing the optical density of the reaction region 12A of the analytical chip 12 and outputs it to the processor 90. The photometric unit 70 includes multiple types of light-emitting elements and an area sensor. This is one embodiment of the photometric device of the present disclosure. Details of the photometric unit 70 will be described later.

[0028] The analysis device 100 further includes a color plate 75 arranged within the imaging range of the area sensor. The color plate 75 has an area onto which light from all of the multiple types of light-emitting elements is irradiated.

[0029] The tip disposal mechanism 80 includes a thin plate-shaped tip transport member 82 and a drive mechanism 84 that reciprocates the tip transport member 82. The tip disposal mechanism 80 inserts the tip transport member 82 into the cell S from the outer periphery of the incubator 60, and pushes the used analytical chip 12 after measurement to the center of the incubator 60, causing it to drop into the disposal hole 68. The drive mechanism 84 is, for example, a linear actuator. The tip transport member 82 is slidably supported by a guide rod (not shown), and is reciprocated by the drive mechanism 84. A collection box for collecting used analytical chips 12 is provided below the disposal hole 68.

[0030] The processor 90 comprehensively controls each component of the analyzer 100. While the processor 90 may have any configuration, it may be configured, for example, with a central processing unit (CPU), non-volatile memory (NVM), and random access memory (RAM). The processor 90 executes programs to perform measurement processing in the analyzer 100. The processor 90 derives the concentration of the target substance contained in the specimen based on the detection signal acquired from the photometric unit 70. Specifically, the processor 90 derives the optical density from the reflected light intensity value of the reaction area 12A and derives the concentration of the target substance based on a calibration curve showing the relationship between the optical density and the concentration of the target substance. In addition to the luminance data of the reaction area 12A, the processor 90 extracts correction luminance data, which is luminance data of the color plate 75, from the image and corrects the measurement value using the correction luminance data. The processor 90 also changes the extraction area for the correction luminance data extracted from the image depending on the type of light-emitting element.

[0031] As shown in Figure 4, the analytical chip 12 has a planar reaction area 12A to which a reagent is fixed. The reagent reacts with the substance to be detected to produce a substance that develops a specific color. The substance that develops color as a result of this reaction will be referred to as a reaction substance hereinafter. For example, a dry reagent that is in a dry state at least at the time of shipment is used as the reagent. A specimen sample is applied to the reaction area 12A of the analytical chip 12.

[0032] The analytical chip 12 has a carrier 16 onto which a specimen sample is deposited, and the carrier 16 is housed in a case 17. The case 17 is composed of a first case 17A and a second case 17B, with the carrier 16 sandwiched between the first case 17A and the second case 17B. The first case 17A has an opening 17C that functions as a drip port for depositing the specimen sample onto the reaction area 12A. The second case 17B has an opening 17D for irradiating the reaction area 12A with light. The carrier 16 is exposed to the opening 17C of the first case 17A, which constitutes the front surface of the analytical chip 12. The carrier 16 is also exposed to the opening 17D of the second case 17B, which constitutes the back surface of the analytical chip 12. The area of ​​the carrier 16 exposed to the opening 17D constitutes the reaction area 12A to which the reagent is immobilized. The second case 17B is also provided with an information code 17E that encodes item information regarding the measurement item. The information code 17E is, for example, a pattern in which a plurality of dots are arranged, and the dot arrangement pattern differs for each measurement item. Of course, one-dimensional barcodes, two-dimensional barcodes, etc. may also be used as the information code 17E.

[0033] By preparing multiple analytical chips 12 each containing a different type of reagent to react with the specimen, it becomes possible to analyze the specimen for multiple measurement items. An analytical chip 12 is prepared for each measurement item, and a carrier 16 holding a reagent corresponding to the measurement item is fixed to the analytical chip 12. The item information assigned to each analytical chip 12 includes identification information (such as the reagent name and identification code) of the reagent fixed to the carrier 16 of the analytical chip 12, or identification information (such as the item name and identification code) of the measurement item measured by the reagent.

[0034] 3, an insertion opening 14B into which the chip transport member 42 is inserted is provided in the side wall of the stocker 14. The chip transport member 42 is inserted into the stocker 14 through the insertion opening 14B.

[0035] The stocker 14 has an opening 14A on its bottom surface. The analytical chips 12 are stored in a position where the surface on which the information code 17E is recorded faces the opening 14A of the stocker 14. Therefore, the information code 17E of the analytical chip 12 located at the bottom, closest to the opening 14A, in the stocker 14 is exposed from the opening 14A. An opening 11A is also formed in the holder 11 on which the stocker 14 is placed. Therefore, the information code 17E of the analytical chip 12 located at the bottom in the stocker 14 is exposed to the reader 20 through the opening 11A of the holder 11 and the opening 14A of the stocker 14. The reader 20 is disposed below the holder 11 and reads the information code 17E exposed through the openings 11A and 14A.

[0036] The chip transport member 42 is pressed against the analytical chip 12 stored in the lowest row of the analytical chips 12 stacked in the stocker 14. In this state, the chip transport member 42 moves toward the incubator 60, thereby transporting the analytical chip 12 to the incubator 60.

[0037] In the incubator 60, the analytical chip 12 is loaded into a slit-shaped space formed between the cell S of the rotating substrate 62 and the pressing member 64. The analytical chip 12 is warmed in the incubator 60 and transported to a measurement position by the rotation of the incubator 60. The measurement position is a position where a photometric unit 70 is disposed below the rotating substrate 62 and where colorimetric measurement of the analytical chip 12 is performed.

[0038] 5 is a schematic diagram showing the general configuration of the photometric unit 70 and the positional relationship of the analysis chip 12. As shown in Fig. 5, the photometric unit 70 includes a housing 71, an irradiation device 73 for irradiating the reaction area 12A with measurement light L, and an area sensor 74 for capturing an image of the reaction area 12A. The housing 71 includes an optical system (not shown) for collecting reflected light L1 from the reaction area 12A and guiding it to the area sensor 74.

[0039] As will be described in detail later, the irradiation device 73 includes two light-emitting element groups 101 and 102, each equipped with a plurality of light-emitting elements. The wavelength range of the measurement light L is determined according to the substance to be detected (i.e., the measurement item). For example, in this example, as described above, a reaction between the substance to be detected and the reagent produces a reaction substance that develops a specific color. Since the light emitted by the irradiation device 73 is measurement light L for detecting whether a reaction substance has been produced, the wavelength range is determined according to the color produced by the reaction substance. In this example, the measurement light L is, for example, light including a wavelength range absorbed by the reaction substance in order to detect the reaction substance. The plurality of light-emitting elements 1a to 8a (see FIG. 6) provided in the light-emitting element group 101 emit light with different center wavelengths. The plurality of light-emitting elements 1b to 8b (see FIG. 6) provided in the light-emitting element group 102 emit measurement light L with different center wavelengths. Each light-emitting element is used according to the type of analysis chip 12, i.e., the measurement item.

[0040] The wavelength range of the measurement light L is preferably limited to a wavelength range that is absorbed by the reaction substance. Examples of the light-emitting elements 1a to 8a and 1b to 8b that emit the measurement light L include light-emitting diodes (LEDs), organic electroluminescence (EL), and semiconductor lasers.

[0041] When the analysis chip 12 is irradiated with the measurement light L, the area sensor 74 captures an image of a predetermined imaging range including the reaction region 12A of the analysis chip 12. The area sensor 74 is an area sensor, and is, for example, an image sensor such as a CCD camera or a CMOS camera. The area sensor 74 outputs the captured image to the processor 90 (see FIG. 1).

[0042] The analysis in the analysis device 100 is carried out as follows.

[0043] First, the analytical chip 12 is removed from the stocker 14 by the chip transport mechanism 40 and then transported to a spotting position on the chip support base 31. At the spotting position, a sample is spotted onto the analytical chip 12 by the sample spotting unit 30. After the sample has been spotted onto the analytical chip 12, the analytical chip 12 is transported into the incubator 60.

[0044] After the analytical chip 12 is transported into the incubator 60 , the analytical chip 12 is heated by heat generated by a heating means (not shown) in the incubator 60 .

[0045] The analytical chip 12 to be measured is transported to a measurement position where a photometric unit 70 is provided by rotation of the rotating platform 62. Then, at the measurement position, colorimetric measurement is performed on the analytical chip 12. The photometric unit 70 irradiates the analytical chip 12 with measurement light L and receives reflected light L1 from the analytical chip 12, thereby measuring the optical density in the analytical chip 12 according to the reaction state between the specimen and the reagent, and outputs a detection signal. The processor 90 derives the concentration of the substance to be detected from the detection signal obtained from the photometric unit 70.

[0046] In the reaction area 12A, the specimen sample and the reagent react to produce a reactant that develops a specific color. The reaction area 12A changes color as a result of the reaction, and this color change manifests itself as a change in the optical density of the reaction area 12A. The reflected light L1 is light that corresponds to the optical density of the reaction area 12A, and information about the reactant is reflected in the reflected light L1 due to factors such as light absorption by the reactant. The optical density of the reaction area 12A changes depending on the amount of reactant, and the amount of reactant represents the concentration of the target substance in the specimen. Therefore, the concentration of the target substance can be measured based on a detection signal that represents the reflected light L1, which contains information about the reactant.

[0047] After the measurement is completed, the analytical chip 12 is transported by the rotating substrate 62 to a position where the chip disposal mechanism 80 is located. The analytical chip 12 is then transported by the chip disposal mechanism 80 (see FIG. 2 ) from inside the incubator 60 to a disposal position provided in the center of the rotating substrate 62. The chip transport member 82 pushes out the analytical chip 12, moving the analytical chip 12 from inside the incubator 60 to the disposal hole 68.

[0048] The photometry unit 70 will be described in detail below.

[0049] As explained with reference to Fig. 5, the irradiation device 73 includes two light-emitting element groups 101 and 102. Hereinafter, one of the two light-emitting element groups 101 and 102 will be referred to as the first light-emitting element group 101, and the other as the second light-emitting element group 102. Fig. 6 is a perspective view showing the positional relationship between the analysis chip 12, the first light-emitting element group 101, the second light-emitting element group 102, and the area sensor 74 shown in Fig. 5. Note that the color plate 75 is omitted from Fig. 6. Fig. 7 is a plan view showing the color plate 75, the irradiation device 73, and the area sensor 74 viewed from the rotating substrate 62 side.

[0050] As shown in FIG. 6 , the first light-emitting element group 101 includes eight light-emitting elements 1a to 8a on a support substrate 111, and the second light-emitting element group 102 includes eight light-emitting elements 1b to 8b on a support substrate 112. As shown in the plan view of FIG. 7 , the first light-emitting element group 101 and the second light-emitting element group 102 are arranged opposite each other with the area sensor 74 sandwiched between them in a planar view. The first light-emitting element group 101 and the second light-emitting element group 102 are arranged such that the support substrates 111 and 112 are tilted relative to the normal to the analytical chip 12. Eight light-emitting elements 1a to 8a and 1b to 8b are arranged in two rows on the support substrates 111 and 112, respectively. On the support substrate 111, the first row, which faces the rotatable substrate 62, is arranged in the order of 8a, 7a, 6a, and 5a from the outer periphery of the rotatable substrate 62, and the second row is arranged in the order of 4a, 3a, 2a, and 1a from the outer periphery of the rotatable substrate 62. In contrast, on the support substrate 112, in the first row on the rotating substrate 62 side, the elements are arranged in the order of 1b, 2b, 3b, and 4b from the outer periphery of the rotating substrate 62, and in the second row, the elements are arranged in the order of 5b, 6b, 7b, and 8b from the outer periphery of the rotating substrate 62.

[0051] As described above, the eight light-emitting elements 1a to 8a of the first light-emitting element group 101 emit light in different wavelength ranges. Similarly, the eight light-emitting elements 1b to 8b of the second light-emitting element group 102 emit light in different wavelength ranges. Hereinafter, the light-emitting elements of the first light-emitting element group 101 will be referred to as first light-emitting elements 1a, 2a, 3a, etc., and the light-emitting elements of the second light-emitting element group 102 will be referred to as second light-emitting elements 1b, 2b, 3b, etc. In this example, elements with the same number, such as the first light-emitting element 1a and the second light-emitting element 1b, and the first light-emitting element 2a and the second light-emitting element 2b, emit light in the same wavelength range. In other words, the irradiation device 73 includes eight light-emitting element pairs that emit light of the same wavelength. Note that light in the same wavelength range refers to light whose center wavelengths match within a range of ±5 nm, and light whose wavelengths match within a range of ±5 nm is referred to as light of the same wavelength.

[0052] When measuring one analytical chip 12, a pair of light-emitting elements consisting of two light-emitting elements with the same central emission wavelength corresponding to the analytical chip 12 is selectively used from the first light-emitting elements 1a to 8a of the first light-emitting element group 101 and the second light-emitting elements 1b to 8b of the second light-emitting element group 102.

[0053] As already described, the color plate 75 is placed within the imaging range of the area sensor 74. In this example, as shown in Fig. 7, the color plate 75 is a rectangular member and has a rectangular opening. Note that "the color plate 75 is placed within the imaging range of the area sensor 74" does not mean that the entire color plate 75 is placed within the imaging range, but rather that at least a portion of the color plate 75 is within the imaging range.

[0054] 8 is an image P captured by the area sensor 74. The outline of the circular part in the center is the outline of the opening window 62A of the rotating platform 62, and the inside of the circular part is the reaction area 12A of the analysis chip 12 observed through the opening window 62A. The gray members located on both sides of the image P are color plates 75.

[0055] The processor 90 acquires the image P from the area sensor 74 of the photometric unit 70. The processor 90 calculates the concentration of the detection target substance based on the measurement value corresponding to the luminance data of the reaction area 12A extracted from the acquired image P. In this embodiment, in addition to the luminance data of the reaction area 12A, the processor 90 extracts correction luminance data, which is the luminance data of the color plate 75, from the image P and corrects the measurement value using the correction luminance data. The processor 90 changes the extraction area of ​​the correction luminance data extracted from the image P depending on the type of light-emitting element that emitted the measurement light L when the image P was acquired. For example, if the image P is obtained by irradiating the reaction area 12A of the analysis chip 12 with measurement light L from the first light-emitting element 1a and the second light-emitting element 1b, the region R1 in the color plate 75 of the image P is used as the extraction area for the correction luminance data. If the image P is obtained by irradiating the reaction area 12A of the analysis chip 12 with measurement light L from the first light-emitting element 1a and the second light-emitting element 2a and the second light-emitting element 2b, the region R2 in the color plate 75 of the image P is used as the extraction area for the correction luminance data. In this example, when the image P is obtained by irradiating the reaction area 12A of the analysis chip 12 with measurement light L from the first light-emitting element 3a and the second light-emitting element 3b, the region R3 in the color plate 75 of the image P is used as the extraction region for correction brightness data. When the image P is obtained by irradiating the reaction area 12A with measurement light L from the first light-emitting element 4a and the second light-emitting element 4b, the region R4 in the color plate 75 of the image P is used as the extraction region for correction brightness data. Note that the positional relationships of the pairs of light-emitting elements 5a and 5b, 6a and 6b, 7a and 7b, and 8a and 8b are equivalent to the positional relationships of the pairs of light-emitting elements 1a and 1b, 2a and 2b, 3a and 3b, and 4a and 4b. Therefore, in this example, the regions R1, R2, R3, or R4 of the pairs of light-emitting elements 5a and 5b, 6a and 6b, 7a and 7b, and 8a and 8b are used as the extraction regions for correction brightness data.

[0056] In this example, for example, when the measurement light L is irradiated using the first light-emitting element 1a and the second light-emitting element 1b, the light intensity distribution of the irradiated measurement light L on the color plate 75 has a larger light intensity around region R1 than other regions. Also, for example, when the measurement light L is irradiated using the first light-emitting element 2a and the second light-emitting element 2b, the light intensity distribution of the irradiated measurement light L on the color plate 75 has a larger light intensity around region R2 than other regions. Thus, in this example, when extracting correction luminance data from the color plate 75, it is preferable to use a region where the irradiation intensity of the irradiated measurement light L is as large as possible for each light-emitting element used for irradiation.

[0057] A method for deriving the concentration of the detection target substance in the processor 90 when the image P is obtained by irradiating the reaction area 12A of the analysis chip 12 with measurement light L from the light emitting elements 1a and 1b will be described.

[0058] For example, the processor 90 designates the center of the reaction region 12A shown in FIG. 8 as the region of interest ROI and derives the average value A of the luminance data in this range as the measurement value. Then, the two regions R1 are designated as regions for extracting correction luminance data, and the luminance data in this range is used as correction luminance data and the average value B is derives as the correction value. The processor 90 then derives the value A / B, which is the average value of the luminance data in the ROI divided by the correction luminance data, as the corrected measurement value. The processor 90 then derives the concentration value of the detection target substance from the calibration curve based on this corrected measurement value.

[0059] The processor 90 uses one of the regions R1 to R4 as an extraction region for extracting corrected brightness data for each light-emitting element illuminated when capturing the image P, as described above, and derives the concentration value of the substance to be detected using the procedure described above.

[0060] In an apparatus capable of measuring multiple types of analytical chips containing different reagents for detecting different target substances, such as the present analytical device 100, multiple types of light-emitting elements are selectively lit because each analytical chip selectively emits light with a different center wavelength. In the analytical device 100, the temperature of the light-emitting element varies depending on the timing and number of times it is lit. The light intensity of the light-emitting element may vary depending on the temperature. Specifically, for example, if the light-emitting element is an LED, the light intensity decreases as the temperature increases and increases as the temperature decreases. Therefore, even if the concentration of the target substance is the same, the optical density of the reaction region 12A may vary depending on the timing and number of times the light-emitting element is lit. In the analytical device 100 of this embodiment, a color plate 75 is provided within the imaging range of the area sensor 74, and the luminance data of the reaction region 12A in the image P is corrected using the correction luminance data, which is the luminance data of the color plate 75. Normalization using the luminance data of the color plate 75 reduces the variance in the measured values ​​due to fluctuations in the light-emitting element's luminance. As a result, the accuracy of the concentration value of the target substance can be improved.

[0061] Figure 9 shows the results (comparison example) of irradiating a test chip with a constant optical density with measurement light L from the same light-emitting element multiple times (65 times), capturing images using a CMOS sensor (area sensor), and deriving a measurement value that is the average value of the luminance data of the region of interest (ROI) of the reaction area 12A. Figure 10 shows corrected measurement values ​​(example) in which the measurement values ​​obtained in Figure 9 are normalized by the average value of the luminance data of a specific region of the color plate 75. In Figures 9 and 10, the horizontal axis represents the number of measurements, and the vertical axis represents the variation of the measurement values ​​from the average of all 65 measurement values. As shown in Figures 9 and 10, the measurement values ​​before correction had a variation of more than ±1%, but the variation in the measurement values ​​after correction was reduced to approximately ±0.3%.

[0062] In the present analysis device 100, when extracting correction luminance data from the color plate 75, the area where the irradiated measurement light L is as large as possible for each light-emitting element used for irradiation is used. The light intensity distribution of the irradiated light on the color plate changes depending on the arrangement position of the light-emitting element. As in this example, by using luminance data from an area with a high light intensity, more accurate measurement results can be obtained.

[0063] In this example, the color plate 75 is a single component, but the color plate 75 may be composed of multiple components. The optical density of the color plate 75 is preferably 1.5 or less, and more preferably 1.0 or less, i.e., the reflectance is 10% or more. The color plate 75 is preferably gray or white. This is because the greater the amount of reflected light and the higher the luminance value of the color plate in the image P captured by the area sensor 74, the more improved the correction accuracy.

[0064] In this example, the color plate 75 is monochromatic, but it may have multiple color regions or may have a gradation of shades. If it has multiple color regions, the processor 90 preferably selects, according to the type of light-emitting element, a color region in which the amount of reflected light of the measurement light L having the center emission wavelength of the light-emitting element is high as the region for extracting the correction luminance data.

[0065] In the photometric unit 70 of the present analysis device 100, the irradiation device 73 is provided with two light-emitting elements that emit light in the same wavelength range, but the number of light-emitting elements that emit light in the same wavelength range may be one, or three or more.

[0066] In this example, the color plate 75 is used to correct the brightness data of the reaction region 12A of the analysis chip 12, but the brightness data of the color plate 75 can also be used to detect malfunctions of the light-emitting elements 1a-8a and 1b-8b. For example, the processor 90 acquires an image P when the measurement light L is irradiated for each type of light-emitting element, and acquires the brightness value of a predetermined location for each type of light-emitting region. The processor 90 stores the brightness value of that location when the light-emitting element is lit normally as a reference brightness value in memory or the like, and compares this reference brightness value with the brightness value at the time of measurement. The processor 90 may be configured to issue an alert if the difference between the two is greater than a certain level, indicating that the light-emitting element may be malfunctioning.

[0067] In the above embodiment, the hardware structure of the processor 90 may be any of the following various processors: The various processors include a CPU, which is a general-purpose processor that executes software (programs) and functions as various processing units, as well as dedicated electrical circuits such as a PLD (Programmable Logic Device) whose circuit configuration can be changed after manufacture, such as an FPGA (Field-Programmable Gate Array), and an ASIC (Application Specific Integrated Circuit), which is a processor having a circuit configuration specifically designed to execute specific processing.

[0068] The above-described processing may be performed by one of these various processors, or by a combination of two or more processors of the same or different types (e.g., a plurality of FPGAs, or a combination of a CPU and an FPGA). Furthermore, a plurality of processing units may be configured by a single processor. An example of configuring a plurality of processing units by a single processor is a system-on-chip (SOC), in which a processor is used to realize the functions of an entire system including a plurality of processing units on a single IC (Integrated Circuit) chip.

[0069] Furthermore, more specifically, the hardware structure of these processors can be an electric circuit that combines circuit elements such as semiconductor elements.

[0070] In addition to the operating program of the analytical device, the technology disclosed herein also extends to a computer-readable storage medium (such as a USB memory or a DVD (Digital Versatile Disc)-ROM (Read Only Memory)) that non-temporarily stores the operating program of the analytical device.

[0071] The above-described description and illustrations are a detailed explanation of the parts related to the technology of the present disclosure and are merely an example of the technology of the present disclosure. For example, the above description of the configuration, functions, actions, and effects is an explanation of an example of the configuration, functions, actions, and effects of the parts related to the technology of the present disclosure. Therefore, it goes without saying that unnecessary parts may be deleted, new elements may be added, or replacements may be made to the above-described description and illustrations within the scope of the gist of the technology of the present disclosure. Furthermore, to avoid confusion and facilitate understanding of the parts related to the technology of the present disclosure, the above-described description and illustrations omit explanations of common technical knowledge that do not require particular explanation to enable the implementation of the technology of the present disclosure.

[0072] The disclosure of Japanese Patent Application No. 2023-156445, filed on September 21, 2023, is incorporated herein by reference in its entirety. All documents, patent applications, and technical standards described herein are incorporated herein by reference to the same extent as if each individual document, patent application, and technical standard were specifically and individually indicated to be incorporated by reference.

Claims

1. An analytical device in which an analytical chip having a reaction area for holding a reagent is removably mounted and which analyzes a specimen sample dropped onto the reaction area of ​​the analytical chip, the analytical device comprising: a photometric unit which optically detects color produced by a reaction between the reagent and a substance to be detected in the specimen sample, the photometric unit including a plurality of types of light-emitting elements arranged at different positions and which selectively irradiate the reaction area with light of different center wavelengths, and an area sensor which captures an image of a predetermined shooting range including the reaction area irradiated with light from the light-emitting elements; a color plate which is arranged within the shooting range and has an area irradiated with light from all of the plurality of types of light-emitting elements; and a processor which acquires the image from the photometric unit and calculates the concentration of the substance to be detected based on a measurement value corresponding to luminance data of the reaction area extracted from the acquired image, the processor extracting correction luminance data, which is the luminance data of the color plate, from the image in addition to the luminance data of the reaction area, and correcting the measurement value with the correction luminance data, the processor changing the extraction area of ​​the correction luminance data extracted from the image depending on the type of the light-emitting element emitting light.

2. The analytical device according to claim 1, wherein the analytical chip includes a dry reagent as the reagent.

3. The analytical device according to claim 1 or 2, wherein the optical density of the color plate is 1.5 or less.

4. The analytical device according to claim 1 or 2, wherein the color plate is monochromatic.

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