JP2009250720A - Autoanalyzer and method for analyzing liquid sample - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an autoanalyzer and a method for analyzing a liquid sample, capable of performing photometry in a region where the quantity of the transmitted light is stable, regardless of the size of a reaction vessel. <P>SOLUTION: The autoanalyer and the method for analyzing the liquid sample analyze the liquid sample, based on an optical characteristic value of a light emitted from a light source, transmitted when crossing the reaction vessel holding the liquid sample and measured by a photometric means. The autoanalyzer is provided with a calculation part 15, including a photometric value obtaining part 15a for obtaining the time-dependent change of the photometric value measured by the photometric means; a temporal differentiation value calculating part 15b for calculating the temporal differentiation value of the photometric value; a time region specifying part 15c for specifying the time region, based on a predetermined threshold value; a process value calculation part 15d for calculating the calculation process value of the photometric value contained in the time region; an optical characteristic value calculation part 15e for calculating the optical characteristics value of the liquid sample, based on the calculation process value; and a component concentration specifying part 15f for specifying the component or concentration, based on the optical characteristic values. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

  The present invention relates to an automatic analyzer and a method for analyzing a liquid sample.

  Conventionally, an automatic analyzer for analyzing a biological sample (specimen) such as blood dispenses and reacts a specimen and a reagent in a reaction container, and optically measures the liquid sample after the reaction, whereby the components of the specimen are analyzed. The concentration and the like are analyzed (for example, see Patent Document 1).

Utility Model Registration No. 2534624

  By the way, as shown in FIG. 10, the automatic analyzer disclosed in Patent Document 1 has a predetermined time from the time (t1) when the converted voltage of the transmitted light passing through the liquid sample exceeds the reference voltage value (V0). The transmitted light is sampled within the photometric time during which the amount of transmitted light from the time (t2) to the time (t3) is stable, and the time (t1) to the time (t2) before and after the sampling time Ts. A margin time Tm extending from time (t3) to time (t4) is set. For this reason, in the automatic analyzer of Patent Document 1 in which the relative movement speed of light with respect to the reaction container is constant, the width W of the reaction container C along the direction in which the light beam BL crosses is determined as shown in FIG. There was a problem.

  On the other hand, in recent years, automatic analyzers are required to reduce the amounts of specimens and reagents in order to reduce the burden on the human body and reduce the operating costs of the apparatus. In this case, it is necessary to reduce the size of the reaction container as the amount of the sample and the reagent is reduced. However, the automatic analyzer disclosed in Patent Document 1 has a sampling time in which the amount of transmitted light is stable while the margin time Tm is secured. In order to secure Ts, there was a restriction on the miniaturization of the reaction vessel.

  The present invention has been made in view of the above, and provides an automatic analyzer and a liquid sample analysis method that enable photometry in a region where the amount of transmitted light is stable regardless of the size of the reaction vessel. For the purpose.

  In order to solve the above-described problems and achieve the object, the automatic analyzer of the present invention is an optical analyzer for the light emitted from the light source and transmitted when crossing the reaction vessel holding the liquid sample, and measured by the photometric means. An automatic analyzer for analyzing the liquid sample based on a characteristic value, the photometric value acquisition means for acquiring the photometric value measured by the photometric means for each reaction container, and the temporal change A time differential value calculating means for calculating a time differential value of a photometric value over time, a time domain specifying means for specifying a time domain based on a predetermined threshold of the time differential value, and the specified time domain A processing value calculation means for calculating a calculation processing value of the photometric value, an optical characteristic value calculation means for calculating an optical characteristic value of the liquid sample based on the calculation processing value, and the optical characteristic value Based on the component or concentration of the liquid sample Characterized by comprising an arithmetic unit having a component concentration specifying means constant for, a.

  In the automatic analyzer of the present invention, in the above invention, the photometric value acquisition unit applies the light transmitted through the liquid sample held by the reaction vessel to the liquid sample out of the light measured by the photometric unit. It is characterized in that a change in time of a relative photometric value with respect to incident light is acquired.

  Further, the automatic analyzer according to the present invention is characterized in that, in the above invention, the optical characteristic value calculation means sets the average value of the time differential values included in the specified time region as the calculation processing value. To do.

  In order to solve the above-described problems and achieve the object, the liquid sample analysis method of the present invention is emitted from a light source and transmitted when crossing a reaction container holding a liquid sample, and photometric means measures the light. A liquid sample analysis method for analyzing the liquid sample based on optical characteristic values of light, wherein a photometric value acquisition step of acquiring, for each reaction container, a temporal change in the photometric value measured by the photometric means, A time differential value calculating step of calculating a time differential value of the photometric value over time based on the time change, and a time region specifying step of specifying a time region based on a predetermined threshold of the time differential value A processing value calculation step of calculating a calculation processing value of the photometric value included in the time domain; an optical characteristic value calculation step of calculating an optical characteristic value of the liquid sample based on the calculation processing value; The liquid sample based on optical characteristic values Characterized in that it comprises a component concentration specifying step of specifying a component or concentration, the.

  In the method for analyzing a liquid sample according to the present invention, in the above invention, the photometric value acquisition step may be a method of measuring a relative photometric value of light transmitted through the liquid sample held by the reaction vessel with respect to light incident on the liquid sample. It is characterized by acquiring a time change.

  In the liquid sample analysis method of the present invention, in the above invention, the optical characteristic value calculation step may use an average value of the time differential values included in the specified time region as the calculation processing value. Features.

  The automatic analyzer according to the present invention includes a photometric value acquisition unit that acquires, for each reaction vessel, a time change of a photometric value measured by the photometric unit, and a time for calculating a time differential value of the photometric value over time based on the time change. Differential value calculation means, time domain specification means for specifying a time domain based on a predetermined threshold value of time differential values, process value calculation means for calculating calculation processing values of photometric values included in the specified time domain, Calculation having optical characteristic value calculation means for calculating the optical characteristic value of the liquid sample based on the calculation processing value, and component concentration specifying means for specifying the component or concentration of the liquid sample based on the optical characteristic value The method for analyzing a liquid sample of the present invention includes a photometric value acquisition step of acquiring, for each reaction container, a time change of a photometric value measured by a photometric means, and a time differential value of the photometric value based on the time change. Time differential value calculation process that calculates over time and time A time region specifying step for specifying a time region based on a predetermined threshold value of a minute value, a processing value calculating step for calculating a processing value of a photometric value included in the specified time region, and a liquid based on the processing value An optical characteristic value calculating step for calculating the optical characteristic value of the sample, and a component concentration specifying step for specifying the component or concentration of the liquid sample based on the optical characteristic value are included. For this reason, the automatic analyzer and the method for analyzing a liquid sample according to the present invention have an effect that light can be measured in a region where the amount of transmitted light is stable regardless of the size of the reaction vessel.

  DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments according to an automatic analyzer and a liquid sample analysis method of the present invention will be described in detail with reference to the drawings. FIG. 1 is a schematic configuration diagram of an automatic analyzer according to the present invention. FIG. 2 is a schematic configuration diagram of the cuvette wheel, photometric device, control unit, input unit, and display unit of the automatic analyzer shown in FIG. FIG. 3 is a perspective view of a reaction vessel used in the automatic analyzer shown in FIG.

  As shown in FIG. 1, the automatic analyzer 1 includes a sample table 3, a sample dispensing mechanism 5, a cuvette wheel 6, a photometric device 8, a cleaning device 9, a reagent dispensing mechanism 10, a reagent table 11, and a work table 2. A stirring device 20 is provided.

  As shown in FIG. 1, the sample table 3 is rotated in the direction indicated by the arrow by the driving means, and a plurality of storage chambers 3 a are provided on the outer periphery at regular intervals along the circumferential direction. In each storage chamber 3a, a sample container 4 storing a sample is detachably stored.

  The sample dispensing mechanism 5 is means for dispensing a sample into a plurality of reaction containers 7 held by a cuvette wheel 6 and sequentially reacts the samples from the plurality of sample containers 4 in the sample table 3 as shown in FIG. Dispense into container 7.

  The cuvette wheel 6 is rotated in a clockwise direction indicated by an arrow in FIG. 1 by a pulse motor M (see FIG. 2), and a plurality of holders 6a for individually holding the reaction vessels 7 are arranged on the outer circumference at equal intervals along the circumferential direction. Is provided. The cuvette wheel 6 rotates, for example, clockwise (1 turn-1 reaction vessel) / 4 minutes in one cycle. The reaction vessel 7 moves one holder 6a counterclockwise in four cycles. In the vicinity of the outer periphery of the cuvette wheel 6, a photometric device 8, a cleaning device 9, and a stirring device 20 are arranged.

  The reaction vessel 7 has a capacity made of a transparent material that transmits 80% or more of the light contained in the analysis light emitted from the light source of the photometric device 8, for example, glass including heat-resistant glass, synthetic resin such as cyclic olefin or polystyrene. The cuvette is a very small amount (several nL to several tens of μL). As shown in FIG. 3, the reaction container 7 includes a side wall 7a, 7b and a bottom wall 7c that form a liquid holding part 7d that holds a liquid containing a reagent, a specimen, and the like. An opening 7e is formed above the liquid holding part 7d. Have. The reaction vessel 7 is arranged in the holder 6a with the side wall 7b facing the radial direction of the cuvette wheel 6. Here, when the reaction vessel 7 crosses the light beam BL emitted from the light source 8a of the photometry device 8 as the cuvette wheel 6 rotates, the lower portion of the side wall 7b is used as a photometry region Am through which the light beam BL passes. .

  As shown in FIGS. 1 and 2, the photometric device 8 is disposed near the outer periphery of the cuvette wheel 6, and a light source 8a that emits light for analysis, and a photometric unit that measures the intensity of light transmitted through the liquid for each wavelength. 8b and an AD converter 8c for converting optical signals output from the photometry unit 8b into digital values. The light source 8a and the photometry unit 8b are arranged at positions facing each other in the radial direction across the holder 6a of the cuvette wheel 6. The photometry unit 8b measures, for example, a diffraction grating such as a concave diffraction grating and the light dispersed by the diffraction grating for each spectrum determined by the measurement item, and outputs a light signal relating to the light quantity, a CCD sensor, a CMOS sensor And other light receiving sensors.

  The cleaning device 9 has a discharging means for discharging the liquid and the cleaning liquid from the reaction vessel 7 and a cleaning liquid dispensing means. The cleaning device 9 dispenses the cleaning liquid after discharging the liquid after photometry from the reaction container 7 after photometry. The cleaning device 9 cleans the inside of the reaction vessel 7 by repeating the operation of dispensing and discharging the cleaning liquid a plurality of times. The reaction container 7 washed in this way is used again for analysis of a new specimen.

  The reagent dispensing mechanism 10 is a means for dispensing a reagent to a plurality of reaction containers 7 held by the cuvette wheel 6, and sequentially reacts the reagents from a predetermined reagent container 12 of the reagent table 11 as shown in FIG. Dispense into container 7.

  The reagent table 11 is rotated in a direction indicated by an arrow in FIG. 1 by a driving means different from the sample table 3 and the cuvette wheel 6, and a plurality of storage chambers 11a formed in a sector shape are provided along the circumferential direction. In each storage chamber 11a, the reagent container 12 is detachably stored. Each of the plurality of reagent containers 12 is filled with a predetermined reagent corresponding to a test item, and an information recording medium (not shown) such as a barcode label for displaying information on the stored reagent is attached to the outer surface.

  Here, on the outer periphery of the reagent table 11, as shown in FIG. 1, information such as the type, lot, and expiration date of the reagent recorded on the information recording medium affixed to the reagent container 12 is read and sent to the control unit 14. A reading device 13 for outputting is installed.

  The control unit 14 includes a sample table 3, a sample dispensing mechanism 5, a reaction wheel 6, a photometric device 8, a cleaning device 9, a reagent dispensing mechanism 10, a reagent table 11, a reading device 13, an input unit 18, a display unit 19, and an agitation. It is connected to the device 20 and the like to control these operations, and for example, a microcomputer or the like is used. As shown in FIG. 2, the control unit 14 includes a calculation unit 15, a storage unit 16, and a drive control unit 17.

  The calculation unit 15 analyzes the component concentration of the specimen from the absorbance of the liquid sample in the reaction container 7 based on the light quantity measured by the photometry unit 8b of the photometry device 8 via the control unit 14, and sends the analysis result to the control unit 14. Output. As shown in FIG. 4, the calculating unit 15 includes a photometric value acquiring unit 15a, a time differential value calculating unit 15b, a time region specifying unit 15c, a processing value calculating unit 15d, an optical characteristic value calculating unit 15e, and a component concentration specifying unit 15f. have.

  The photometric value acquisition unit 15a is a ratio of the light transmitted through the liquid sample held by the reaction vessel 7 to the light incident on the liquid sample out of the light measured by the photometric unit 8b, and the maximum value is 1. The time change of the photometric value is acquired (see FIG. 5). The time differential value calculation unit 15b calculates the time differential value of the relative photometric value over time based on the temporal change (see FIG. 5) of the relative photometric value acquired by the photometric value acquisition unit 15a (see FIG. 7).

  The time domain specifying unit 15c specifies the time domain based on a predetermined threshold value of the time differential value calculated by the time differential value calculation unit 15b. The processing value calculation unit 15d calculates the calculation processing value of the relative photometric value included in the time domain specified by the time domain specification unit 15c. As the arithmetic processing value, for example, an average value of relative photometric values included in the specified time domain is used, but may be a relative photometric value at the center of the time domain, a median value of relative photometric values, or the like. .

  The optical characteristic value calculation unit 15e calculates an absorbance that is an optical characteristic value of the liquid sample held in the reaction vessel 7 based on the calculation processing value. The component concentration specifying unit 15f specifies the component or concentration of the liquid sample based on the absorbance calculated by the optical characteristic value calculating unit 15e and the calibration curve stored in the storage unit 16.

  The storage unit 16 includes photometric data relating to the amount of light (optical signal) measured by the photometric unit 8b and the temporal change of the relative photometric value, the time differential value and the average value calculated by the calculation unit 15, a preset time differential value threshold, A calibration curve or the like relating to the component concentration and absorbance of the liquid sample is stored.

  The drive control unit 17 controls the operation of each unit of the automatic analyzer 1 and stops the analysis work when the reagent lot is different or the expiration date is out of date based on the information read from the record of the information recording medium. Thus, the automatic analyzer 1 is controlled, or a function of issuing a warning to the operator by displaying a predetermined content on the display unit 19 is provided.

  The input unit 18 is a part that performs an operation of inputting an inspection item or the like to the control unit 14, and for example, a keyboard or a mouse is used. The display unit 19 displays analysis contents, analysis results, alarms, or the like, and a display panel or the like is used.

  The stirring device 20 is a device that stirs the liquid held in the reaction vessel 7, and includes a device that stirs the liquid directly with a stirring bar and a device that stirs the liquid in a non-contact manner using sound waves.

  In the automatic analyzer 1 configured as described above, the reagent dispensing mechanism 10 sequentially dispenses the reagent from the reagent container 12 to the plurality of reaction containers 7 conveyed along the circumferential direction by the rotating cuvette wheel 6. . The reaction container 7 into which the reagent has been dispensed is conveyed along the circumferential direction by the cuvette wheel 6, and the specimens are sequentially dispensed from the plurality of specimen containers 4 held on the specimen table 3 by the specimen dispensing mechanism 5.

  Then, the reaction container 7 into which the specimen has been dispensed is conveyed to the stirring device 20 by the cuvette wheel 6, and the dispensed reagent and specimen are sequentially stirred and reacted. The reaction container 7 holding the reaction solution in which the sample and the reagent have reacted in this way passes through the photometric device 8 when the cuvette wheel 6 rotates again, and the luminous flux BL of the analysis light emitted from the light source (see FIG. 3). ) Is transmitted. At this time, the light beam BL transmitted through the reaction solution is measured by the photometry unit 8b, and the concentration of the component is determined based on the absorbance calculated by the calculation unit 15 using the average value obtained by averaging the time differential values included in the predetermined range. Is analyzed. After the analysis is completed, the reaction vessel 7 is washed by the washing device 9 and then used again for analyzing the specimen. The automatic analyzer 1 automatically executes such a series of analysis operations under the control of the control unit 14.

In the photometry associated with this series of analysis operations, the photometric value acquisition unit 15a uses the ratio of the light transmitted through the liquid sample held by the reaction vessel 7 to the light incident on the liquid sample out of the light measured by the photometric unit 8b. Thus, the time change of the relative photometric value with the maximum value being 1 is acquired and stored in the storage unit 16. At this time, FIG. 6 is an enlarged view in the vertical axis direction of the region where the relative photometric value is 0.990 or more in the time change diagram shown in FIG. At longitudinal enlarged time change diagram shown in FIG. ^6, the relative photometric value is stabilized in a range of ^{11m · sec -1 ~18m · sec -1} , relative photometric value is greatly changed in the area of both sides. Therefore, the present invention measures the light beam BL transmitted through the reaction liquid held in the reaction vessel 7 in the region where the photometric value is stable.

At this time, at the vertical enlarged time change diagram shown in FIG. 6, the tangent slope ^is nearly flat in a range of ^{11m · sec -1 ~18m · sec -1} , it is read to vary greatly in the region on both sides. In FIG. 6, the slope of the tangent L1 at 11 m · sec ⁻¹ , that is, the time differential value is 1 / sec, and the slope of the tangent L2 at 18 m · sec ⁻¹ , that is, the time differential value is −1 / sec. Met. Therefore, when the time differential value of the relative photometric value, which is the slope of the tangent, is calculated over time by the time differential value calculation unit 15b based on the longitudinal expansion time variation diagram shown in FIG. 6, the result is as shown in FIG.

  Accordingly, in FIG. 7, the time domain AT between the times T1 and T2 is specified by the time domain specifying unit 15c with the time differential value -1 / sec to 1 / sec as a threshold value. Then, an average value M of a plurality of relative photometric values in the time region AT shown in FIG. 8 is calculated by the processing value calculation unit 15d. Absorbance is calculated by the optical characteristic value calculation unit 15e based on the calculated average value M, and the concentration in the reaction container 7 is determined by the component concentration specifying unit 15f based on a calibration curve obtained in advance based on this absorbance. Determine the component or concentration of the liquid sample.

  At this time, the time differential value as the threshold is determined for each automatic analyzer 1 based on the photometric unit 8b used in the photometric device 8, the wavelength used, photometric conditions such as photometric accuracy, measurement (inspection) items, and the like. The data is stored in the storage unit 16. However, if the threshold value is increased too much, as is apparent from FIG. 7, there is a problem that the photometric value falls outside the stable region. On the other hand, if the threshold value is too small, a subtle change in the photometric value in a region where the photometric value is stable will be captured. For this reason, as shown in FIG. 7, it is desirable to set the time differential value as the threshold value to the smallest possible value that sandwiches the region where the photometric value is stable from above and below.

  Therefore, the liquid sample analysis method of the present invention is executed for each reaction vessel 7 by the calculation unit 15 according to the flowchart shown in FIG. 9 under the control of the analysis operation of the automatic analyzer 1 by the drive control unit 17.

  First, the calculating part 15 acquires the time change of a relative photometric value from the optical signal input from the photometry apparatus 8 (step S100). Next, the calculating part 15 calculates a time differential value based on the time change of the relative photometric value acquired at step S100 (step S102). At this time, the calculation unit 15 may calculate the time differential value based on the vertical enlargement time variation diagram in which the region where the relative photometric value is 0.990 or more is enlarged in the vertical axis direction as described above. However, from the viewpoint of avoiding noise errors, higher accuracy can be obtained by directly calculating without using the vertical enlargement time variation diagram as described in step S102.

  Next, the calculation unit 15 specifies a time region based on a preset threshold value of the time differential value (step S104). Thereafter, the calculation unit 15 calculates a calculation processing value (average value) of the relative photometric values within the specified time region (step S106).

  Next, the calculation unit 15 calculates the absorbance using the calculation processing value (average value) (step S108). Next, the calculation unit 15 specifies the component or concentration of the liquid sample based on the calculated absorbance and the calibration curve stored in the storage unit 16 (step S110).

  Thereafter, the calculation unit 15 determines whether or not photometry of all the reaction vessels 7 has been completed (step S112). This determination is performed based on the analysis information input from the input unit 18. As a result of the determination, when the photometry of all the reaction vessels 7 has not been completed (No at Step S112), the calculation unit 15 returns to Step S100 and repeats the subsequent steps. On the other hand, when the photometry of all the reaction containers 7 has been completed (step S112, Yes), the calculation unit 15 ends the calculation related to the analysis of the liquid sample.

  As described above, the automatic analyzer and the liquid sample analyzing method of the present invention finds a region where the photometric value is stable based on the time differential value calculated from the time change of the photometric value, and the optical region within the stable region. The liquid sample is analyzed using the characteristic values. For this reason, the automatic analyzer and the liquid sample analysis method of the present invention can perform photometry in a region where the amount of light transmitted through the reaction vessel 7 is stable. In particular, the automatic analyzer and analysis method of the present invention have the advantage that they can be executed by a common program regardless of the size of the reaction vessel.

  Moreover, the calculating part 15 acquired the time change of the relative photometric value from the optical signal input from the photometry apparatus 8, and calculated the time differential value based on the time change of the relative photometric value. However, the calculation unit 15 may calculate the time differential value from the time change of the optical signal (absolute value) input from the photometry device 8.

It is a schematic block diagram of the automatic analyzer of this invention. It is a schematic block diagram of the cuvette wheel of the automatic analyzer shown in FIG. 1, a photometry apparatus, a control part, an input part, and a display part. It is a perspective view of the reaction container used with the automatic analyzer shown in FIG. It is a block diagram which shows the structure of the calculating part with which the automatic analyzer shown in FIG. 1 is provided. It is a time change figure of the relative photometric value which permeate | transmitted the reaction container. FIG. 6 is a longitudinal enlargement time change diagram in which a region where the relative photometric value is 0.990 or more in the time change diagram shown in FIG. 5 is enlarged in the vertical axis direction. It is a time change figure which shows the time domain specified by the time differential value computed based on the vertical expansion time change figure shown in FIG. 6, and the threshold value of a time differential value. It is a figure which shows the average value of the relative photometry value in the specified time area | region. It is a flowchart explaining the analysis method of the liquid sample of this invention. It is explanatory drawing explaining the sampling time and margin time of the transmitted light in the conventional automatic analyzer. In the conventional automatic analyzer, it is sectional drawing of the reaction container explaining the width | variety of the reaction container along the direction which a light beam crosses.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Automatic analyzer 2 Work table 3 Sample table 4 Sample container 5 Sample dispensing mechanism 6 Cuvette wheel 7 Reaction container 8 Photometric device 8a Light source 8b Photometric unit 8c AD converter 9 Cleaning device 10 Reagent dispensing mechanism 11 Reagent table 12 Reagent container 13 Reading device 14 Control unit 15 Calculation unit 15a Photometric value acquisition unit 15b Time differential value calculation unit 15c Time domain specification unit 15d Process value calculation unit 15e Optical characteristic value calculation unit 15f Component concentration specification unit 16 Storage unit 17 Drive control unit 18 Input Section 19 Display section 20 Stirrer Am Metering area BL Light flux M Pulse motor

Claims (6)

An automatic analyzer for analyzing the liquid sample based on the optical characteristic value of the light emitted from the light source and transmitted across the reaction vessel holding the liquid sample and measured by the photometric means,
A photometric value acquisition means for acquiring a time change of a photometric value measured by the photometric means for each reaction container;
Time differential value calculation means for calculating the time differential value of the photometric value over time based on the time change,
Time domain specifying means for specifying a time domain based on a predetermined threshold of the time differential value;
A processing value calculation means for calculating a calculation processing value of the photometric value included in the identified time region;
An optical characteristic value calculating means for calculating an optical characteristic value of the liquid sample based on the calculation processing value;
Component concentration specifying means for specifying the component or concentration of the liquid sample based on the optical characteristic value;
An automatic analyzer comprising a computing means having   The photometric value acquisition means acquires a change in time of a relative photometric value of light transmitted through the liquid sample held by the reaction vessel with respect to light incident on the liquid sample, out of the light measured by the photometric means. The automatic analyzer according to claim 1, characterized in that:   3. The automatic analyzer according to claim 1, wherein the optical characteristic value calculation unit sets an average value of the time differential values included in the identified time region as the calculation processing value. 4. A liquid sample analysis method for analyzing a liquid sample based on an optical characteristic value of light emitted from a light source and transmitted when crossing a reaction vessel holding a liquid sample, and measured by a photometric means,
A photometric value acquisition step of acquiring the time change of the photometric value measured by the photometric means for each reaction container;
A time differential value calculation step of calculating the time differential value of the photometric value over time based on the time change;
A time domain specifying step of specifying a time domain based on a predetermined threshold of the time differential value;
A processing value calculation step for calculating a calculation processing value of the photometric value included in the identified time region;
An optical characteristic value calculating step of calculating an optical characteristic value of the liquid sample based on the calculation processing value;
A component concentration specifying step of specifying a component or concentration of the liquid sample based on the optical characteristic value;
A method for analyzing a liquid sample, comprising:   5. The liquid according to claim 4, wherein the photometric value acquisition step acquires a temporal change in a relative photometric value of light transmitted through the liquid sample held by the reaction vessel with respect to light incident on the liquid sample. Sample analysis method.   6. The method of analyzing a liquid sample according to claim 4, wherein the optical characteristic value calculation step uses an average value of the time differential values included in the specified time region as the calculation processing value.

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