WO2011001530A1

WO2011001530A1 - Instrument for analyzing body fluid components

Info

Publication number: WO2011001530A1
Application number: PCT/JP2009/062189
Authority: WO
Inventors: 務臼井; 伸一横山
Original assignee: 株式会社ティー・ティー・エム
Priority date: 2009-07-03
Filing date: 2009-07-03
Publication date: 2011-01-06
Also published as: JP5339554B2; JPWO2011001530A1

Abstract

Provided is an instrument for analyzing body fluid components which has a simple structure, enables the performance of an analysis using a simple procedure without a need for precise control of liquid-feeding, and makes it possible to quickly acquire highly accurate analytical data. An instrument for analyzing body fluid components provided with a sample inlet port (2) from which a body fluid sample is supplied into the inside and a reaction chamber (4) communicating therewith through a channel (3) extending therefrom, wherein a first reagent (42) and a second reagent (43) surface-coated with a coating layer (44) are contained in the reaction chamber (4) in an isolated state from each other, the coating layer (44) remains insoluble upon contact with the body fluid sample alone, and the first reagent (42) contains a coating layer-solubilizing agent capable of solubilizing the coating layer. Owing to this constitution, reactions of the body fluid sample with multiple kinds of reagents can be successively conducted in a single reaction chamber and body fluid components can be analyzed at a high accuracy without forming a plural number of reaction chambers within the instrument or conducting precise liquid-feeding.

Description

Body fluid component analyzer

The present invention relates to a body fluid component analyzer that can easily and quickly measure a specific component in a body fluid.

As a simple device that can quickly and accurately perform analysis of specific components in body fluids, drop body fluid samples to cause multiple reactions inside them, and measure physical quantities of body fluid samples after reaction A body fluid component analyzer configured to measure a component to be analyzed by the above is widely used.

For example, when the analysis target is cholesterol (hereinafter referred to as HDL-C) in high-density lipoprotein (hereinafter referred to as HDL), the difference in the specificity of the surfactant with respect to the lipoprotein can be obtained without requiring fractionation. A specimen-like analytical instrument using a so-called direct method of selectively measuring HDL-C is known (see Patent Document 1). In order to specifically measure HDL-C, the analytical instrument disclosed in Patent Document 1 first reacts a dropped fluid sample with a reagent that prevents dissolution of lipoproteins other than HDL, and then reacts with HDL. The reagent is configured to react with a reagent for measuring cholesterol after reacting with a reagent with high solubilization performance. However, since it is necessary to cause a plurality of different reactions to occur in a predetermined order in order to measure a component to be analyzed, in the analytical instrument disclosed in Patent Document 1, each reaction is performed along the traveling direction of the body fluid sample. It was necessary to arrange a reagent for waking up in a layered manner at a predetermined position of the porous body. Moreover, since the movement of the body fluid sample depends on the chromatographic action in the porous body, it is difficult to control the reaction time to be constant.

Also, when the analysis target is glucose, an analytical instrument that can easily measure glucose in a body fluid is also known (see Patent Document 2). Patent Document 2 discloses an analytical instrument for analyzing glucose in a body fluid using a reductase. However, ascorbic acid contained in the body fluid has a reducing property, and thereby the reducing color former is colored. Therefore, ascorbic acid causes a positive error in measurement. Further, when glucose in a body fluid is analyzed using oxidase, ascorbic acid causes a negative error in measurement because peroxidase and ascorbic acid compete and compete for hydrogen peroxide. Therefore, in the analytical instrument disclosed in Patent Document 2, in order to remove the effect of reducing ascorbic acid, the bodily fluid sample is retained in the sample processing chamber equipped with ascorbic acid oxidase for a certain period of time. A structure is adopted in which ascorbic acid is reacted with ascorbic acid oxidase to oxidatively decompose ascorbic acid, and then a body fluid sample is transferred to the photometric chamber by performing precise liquid feeding control to cause a color reaction in the photometric chamber. . That is, in the conventional analytical instrument, it is necessary to separately provide a chamber for causing the first reaction for removing the inhibitor and a chamber for causing the second reaction for measuring the component to be analyzed. Further, in order to transfer a small amount of body fluid sample inside the analytical instrument, a separate device capable of precise liquid feeding control is required.

As described above, when trying to analyze a specific component in a body fluid, first, a first reaction for removing an inhibitor contained in the body fluid sample is caused, and after the first reaction is completed, the component to be analyzed is measured. In some cases, a procedure for causing the second reaction is required. When this analysis procedure is to be carried out with a simple instrument, it is necessary to separate the chamber for causing the first reaction and the chamber for causing the second reaction, and precise liquid feeding control is possible. There was a problem that a separate device was required.

Therefore, a body fluid component that has a simple structure, can perform an analysis with a simple operation without requiring precise liquid feeding control, and can quickly obtain a highly accurate analysis result. Analytical instruments were required.

Japanese Patent No. 3686326 Japanese Patent No. 3480876

The problem to be solved by the present invention is that it has a simple structure, can perform an analysis with a simple operation without requiring precise liquid feeding control, and quickly obtains a highly accurate analysis result. It is an object of the present invention to provide a body fluid component analyzer.

The present invention has been made to solve the above problems, and the invention according to claim 1 includes a sample supply port through which a bodily fluid sample is supplied, a flow path extending from the sample supply port, A reaction chamber communicating with the flow path, a first reagent provided in the reaction chamber, and a second reagent provided separately from the first reagent, the surface of which is covered with a coating layer, The said coating layer is a body fluid component analysis instrument characterized by containing the coating layer dissolving agent which does not melt | dissolve even if it contacts only with the said body fluid sample, and said 1st reagent melt | dissolves the said coating layer.

According to the first aspect of the present invention, when the body fluid sample is supplied to the sample supply port and then sent to the reaction chamber, the first reagent is first dissolved in the body fluid sample, the first reaction starts, and the first reaction ends. After that, the coating layer is dissolved by the coating layer dissolving agent contained in the first reagent, the second reagent is exposed, the second reagent is dissolved in the body fluid sample, and the second reaction is started. That is, it is possible to provide a body fluid component analysis instrument capable of sequentially causing a plurality of reactions in one reaction chamber without providing a plurality of reaction chambers inside the instrument and without performing precise liquid feeding. it can.

The invention according to claim 2 is characterized in that the coating layer comprises a salt of alginic acid and a divalent metal, and the coating layer solubilizer comprises a salt of ethylenediaminetetraacetic acid and an alkali metal. This is a device for analyzing body fluid components.

According to the invention described in claim 2, the bivalent metal in the coating layer is removed by the complexing reaction of ethylenediaminetetraacetic acid, in which the first reagent is dissolved in the body fluid sample flowing into the reaction chamber and released into the reaction chamber. Thus, it is possible to provide a body fluid component analyzing instrument configured such that the coating layer is broken and the second reagent is exposed in the reaction chamber.

The invention described in claim 3 is the body fluid component analyzing instrument according to claim 2, wherein the coating layer is made of calcium alginate.

According to the invention of claim 3, it is possible to provide a body fluid component analysis instrument provided with a coating layer for safely and reliably coating the second reagent.

The invention according to claim 4 is characterized in that the second reagent contains sodium alginate and the coating layer is formed by dropping calcium chloride onto the surface of the second reagent. It is an analytical instrument for the body fluid component described.

According to the invention described in claim 4, it is possible to provide a body fluid component analyzing instrument capable of forming a coating layer covering the surface of the second reagent by a simple method.

The invention according to claim 5 is characterized in that the wall surface surrounding the reaction chamber has water impermeability, and at least a part of the wall surface has air permeability. It is a device for analyzing body fluid components.

According to the fifth aspect of the present invention, there is provided a body fluid component analyzing instrument capable of reliably transferring a body fluid sample to the reaction chamber by simply pressurizing the sample supply port without performing precise liquid feeding control. can do.

The invention according to claim 6 is a water-impermeable and air-permeable ventilation plate, a water-permeable and air-impermeable first sealing plate disposed so as to abut against one plate surface of the ventilation plate, A second sealing plate that is impermeable to water and impermeable to air, and has a through hole that penetrates in the plate thickness direction. The reaction chamber is defined by a hole, the first sealing plate, and the second sealing plate, the first reagent is attached to the first sealing plate, and the second reagent is the second sealing. 6. The body fluid component analysis instrument according to claim 5, which is attached to a stop plate.

According to the sixth aspect of the present invention, the first reagent is attached to the first sealing plate, the second reagent is attached to the second sealing plate, and the coating layer is further formed. It is possible to provide a body fluid component analysis instrument that can be configured by laminating a stop plate and a second sealing plate.

The invention according to claim 7 is the body fluid component according to claim 6, wherein a portion of the first sealing plate and the second sealing plate adjacent to the reaction chamber has light permeability. It is an analytical instrument.

According to the seventh aspect of the present invention, it is possible to provide a body fluid component analysis instrument capable of analyzing a body fluid component by measuring the optical change amount in the reaction chamber after the second reaction is completed. .

According to the present invention, when a body fluid sample is supplied to the sample supply port and then sent to the reaction chamber, the first reagent is first dissolved in the body fluid sample, the first reaction starts, and the first reaction is completed. The coating layer is dissolved by the coating layer solubilizing agent, and the second reagent is exposed, the second reagent is dissolved in the body fluid sample, and the second reaction starts. That is, it is possible to provide a body fluid component analysis instrument capable of analyzing a body fluid component without providing a plurality of reaction chambers inside the instrument and without performing precise liquid feeding.

It is a top view which shows the analytical instrument of the bodily fluid component which concerns on embodiment of this invention. FIG. 2 is a cross-sectional view showing an AA cross section in FIG. 1. It is a disassembled perspective view which shows the analytical instrument of the bodily fluid component which concerns on embodiment of this invention. FIG. 2 is an enlarged cross-sectional view of the reaction chamber in the AA cross-section in FIG. 1, showing dissolution of the reagent after the body fluid sample has flowed into the reaction chamber. It is a figure which shows the time change of the light absorbency in the Example and comparative example of this invention. It is a figure which shows the change of the light absorbency by the density | concentration of the ascorbic acid in a sample in the Example and comparative example of this invention.

Next, an embodiment of the present invention will be described with reference to the drawings. The embodiments described below are preferred embodiments of the present invention, and thus various technically preferable limitations are given. However, the scope of the present invention is particularly limited in the following description. As long as there is no description which limits, it is not restricted to these aspects.

1 to 3 show an embodiment of a body fluid component analyzer according to the present invention. FIG. 1 is a plan view of a humor component analyzing instrument according to the present embodiment, FIG. 2 is a sectional view showing a section AA in FIG. 1, and FIG. 3 is an analysis of a humor component according to the present embodiment. It is a disassembled perspective view of an instrument. FIG. 4 is an enlarged cross-sectional view of the reaction chamber in the AA cross section in FIG. 1, showing the dissolution of the reagent after the body fluid sample flows into the reaction chamber. In the present embodiment, a plasma sample is dropped as a body fluid sample and glucose is measured.

First, the structure of the body fluid component analyzer according to this embodiment will be described. As shown in FIGS. 1 to 3, the body fluid component analysis instrument 1 according to the present embodiment is configured by laminating a first sealing plate 11, a ventilation plate 12, and a second sealing plate 13. Yes. One plate surface 12a of the ventilation plate 12 and the inner plate surface 11a of the first sealing plate 11 abut, and the other plate surface 12b of the ventilation plate 12 and the inner plate surface 13a of the second sealing plate 13 Are brought into contact with each other through an adhesive layer (not shown) such as a double-sided tape.

The first sealing plate 11 is provided with a through hole 21 penetrating in the plate thickness direction to form the sample supply port 2. The ventilation plate 12 is also provided with a through hole 22 penetrating in the thickness direction substantially concentrically with the through hole 21, and a groove 31 extends from the through hole 22. A region surrounded by the groove 31 and the inner plate surface 11 a of the first sealing plate 11 and the inner plate surface 13 a of the second sealing plate 13 defines the flow path 3 extending from the sample supply port 2. ing.

A blood cell separation membrane (not shown) for separating blood cell components is installed at the sample supply port 2, and a whole blood sample is dropped onto the blood cell separation membrane so that a body fluid sample from which the blood cell components have been removed is supplied to the sample supply port 2. It can also be configured to flow in.

The ventilation plate 12 is provided with a through hole 41 that communicates with the groove 31 and penetrates in the thickness direction. A region surrounded by the through hole 41, the inner plate surface 11 a of the first sealing plate 11 and the inner plate surface 13 a of the second sealing plate 13 divides the reaction chamber 4. In the reaction chamber 4, a first reagent 42 is attached to the inner plate surface 11 a of the first sealing plate 11, and a second reagent is attached to the inner plate surface 13 a of the second sealing plate 13. Reagent 43 is attached. Furthermore, a coating layer 44 is provided so as to cover the surface of the second reagent 43. With this configuration, the first reagent 42 and the second reagent 43 can be easily provided separately in the reaction chamber 4.

The second reagent 43 and the coating layer 44 can be provided on the inner plate surface 11 a of the first sealing plate 11, and the first reagent 42 can be provided on the inner plate surface 13 a of the second sealing plate 13. These reagents can also be provided separately at different positions in the reaction chamber 4. Further, at least the through-hole 41 of the first sealing plate 11 and the second sealing plate 13 so that light reaches the reaction chamber 4 from the outside when measuring the optical change amount in the reaction chamber 4 after the reaction. A portion that is substantially concentric with the reaction chamber 4, that is, a portion adjacent to the reaction chamber 4 is configured to have optical transparency. A non-light-transmitting film (not shown) provided with an aperture is attached to the first sealing plate 11 and the second sealing plate 13, or light is transmitted around a region that provides light-transmitting properties. The size of the light-transmitting part can be set, for example, by applying a paint having no property (not shown).

Next, the material of each component will be described. Since the first sealing plate 11 and the second sealing plate 13 are impermeable and impermeable to water, plastic materials such as polyethylene terephthalate (PET) and AS resin are easy to process. Is preferred. However, the present invention is not limited to this as long as a flow path in which the body fluid sample does not leak can be formed.

The ventilation plate 12 is impermeable and breathable, and a porous material that is impermeable and breathable is preferably used. The processing of the holes and grooves is easy, and part of the wall surface surrounding the reaction chamber 4 has air permeability, and air escapes from here, so that the body fluid sample is transferred to the reaction chamber 4 without providing an air vent hole or the like. Because it becomes possible to do. As the water-impermeable and air-permeable porous material, polytetrafluoroethylene (PTFE), cellulose acetate and cellulose mixed ester subjected to water repellent treatment, and the like are preferably used. An air vent hole communicating from the wall surface of the reaction chamber 4 to the outside can also be provided. In this case, the ventilation plate 12 is made of an impermeable and impermeable material in place of the impermeable and breathable material. It can also be used.

The first reagent 42 is configured to dissolve in the body fluid sample to generate a first reaction, and the second reagent 43 is configured to dissolve in the body fluid sample after the first reaction is completed to generate a second reaction. Yes. The first reaction is a reaction in which an inhibitor that inhibits the measurement of the component to be analyzed is removed, and the second reaction is an optical characteristic or electrical characteristic so that the component to be analyzed can be measured. It is a reaction in which the physical quantity changes. After the second reaction is completed, the body fluid sample exhibits changes in physical quantities such as optical characteristics and electrical characteristics. Therefore, the body fluid components can be analyzed by measuring the changes. In the present embodiment, the body fluid component can be analyzed by measuring the optical change amount of the body fluid sample after the second reaction is completed. In addition, by providing an electrode or the like in the reaction chamber 4, it is possible to measure a change in electrical characteristics and analyze a body fluid component.

The surface of the second reagent 43 is covered with a coating layer 44, and the coating layer 44 is made of a material that does not dissolve even when it comes into contact with a body fluid sample. The first reagent 42 contains a coating layer dissolving agent that dissolves the coating layer 44. That is, after the first reaction is completed, the coating layer 44 is dissolved by the action of the coating layer dissolving agent dissolved in the body fluid sample, the second reagent 43 is exposed, and the second reagent 43 is dissolved in the body fluid sample. Two reactions begin. By adjusting the thickness of the coating layer 44 and the concentration of the coating layer solubilizing agent contained in the first reagent 42, the time from when the body fluid sample flows into the reaction chamber 4 until the second reagent 43 is exposed is adjusted. It is possible to control. In this embodiment, the coating layer 44 is made of a salt of alginic acid and a divalent metal, and the coating layer dissolving agent contained in the first reagent 42 is made of a salt of ethylenediaminetetraacetic acid and an alkali metal. According to this configuration, the coating layer 44 is not dissolved by contact with only the body fluid sample, but the coating layer 44 is formed by a complexing reaction of ethylenediaminetetraacetic acid as a coating layer dissolving agent contained in the first reagent 42 dissolved in the body fluid sample. The bivalent metal is removed, the coating layer 44 is destroyed, and the second reagent 43 is exposed.

Although the method of covering the second reagent 43 with the coating layer 44 is arbitrary, the second reagent 43 is allowed to contain sodium alginate, and the second reagent 43 is attached to the second sealing plate 13, and then the surface thereof is applied. When calcium chloride is added dropwise, the surface of the second reagent 43 is changed to calcium alginate, so that the coating layer 44 made of calcium alginate that does not affect the reaction covers the surface of the second reagent 43 by a simple method. It can be formed and is preferred. The thickness of the coating layer 44 to be formed can be adjusted by adjusting the concentration of sodium alginate in the second reagent 43 and the concentration of calcium chloride dropped onto the second reagent 43. Furthermore, by adjusting the concentration of ethylenediaminetetraacetic acid contained in the first reagent 42, the time from when the body fluid sample flows into the reaction chamber 4 until the second reagent 43 is exposed can be easily controlled. it can.

In the present embodiment, when glucose is measured using a reductase, the first reagent 42 contains glucose dehydrogenase and diaphorase, and removes ascorbic acid, which is an inhibitory factor. It is preferable that the second reagent 43 is prepared so as to contain acid oxidase, and the second reagent 43 is prepared so as to contain a reducing color former. When glucose is measured using an oxidase, the first reagent 42 is prepared to contain ascorbate oxidase and an oxidative condensation color former, and the second reagent 43 contains glucose oxidase and peroxidase. It is preferred to prepare to contain. This is because ascorbic acid is removed before the glucose oxidase reaction proceeds so as not to cause a decrease in coloration due to competition between ascorbic acid and peroxidase.

Here, instead of glucose as an analysis target in the present embodiment, HDL-C may be configured as an analysis target. In this case, the first reagent 42 is prepared so as to contain a reagent such as a surfactant that prevents the dissolution of lipoproteins other than HDL, and the second reagent 43 is a surfactant having high solubilizing performance with respect to HDL. And a reagent for enzyme measurement for cholesterol measurement may be prepared.

Next, an analysis procedure using the body fluid component device and the operation of the body fluid component analysis device according to the present embodiment will be described with reference to FIGS.

First, a bodily fluid sample made of plasma is dropped onto the sample supply port 2, and then the sample supply port 2 is pressurized. Here, when a blood cell separation membrane is installed in the sample supply port 2, a whole blood sample can be dropped onto the blood cell separation membrane as a body fluid sample, and the body fluid sample from which the blood cell component has been removed by the blood cell separation membrane is It flows into the sample supply port 2.

The aeration plate 12 has air permeability while impervious to water. Therefore, the wall surface of the reaction chamber 4 is also air permeable, so that the body fluid sample flows into the reaction chamber 4 through the flow path 3 and remains there. FIG. 4 shows an enlarged cross-sectional view of the reaction chamber 4 after the body fluid sample flows into the reaction chamber 4. In FIG. 4, 5 indicates a body fluid sample. FIG. 4A is a view immediately after the body fluid sample 5 flows into the reaction chamber 4.

In the reaction chamber 4, the first reagent 42 starts to dissolve in the body fluid sample 5 by contacting the body fluid sample 5. On the other hand, since the second reagent 43 is covered with the coating layer 44, and the coating layer 44 is not dissolved by contact with only the body fluid sample 5, the second reagent 43 is not yet exposed. As time passes, the first reagent 42 is completely dissolved in the body fluid sample 5 (see FIG. 4B).

The first reaction proceeds by dissolving the first reagent 42 in the body fluid sample 5, and the inhibitory factor present in the body fluid sample 5 that inhibits the measurement of the component to be analyzed is removed. At the same time, the coating layer solubilizer contained in the first reagent 42 dissolves into the body fluid sample 5 and the coating layer 44 is dissolved by the coating layer solubilizer. When the coating layer 44 is broken, the second reagent 43 is exposed. At this stage, the first reaction has been completed and the inhibitor has already been removed. The exposed second reagent 43 is dissolved in the body fluid sample 5, and the second reaction proceeds. Then, with the passage of time, the second reagent 43 is completely dissolved in the body fluid sample 5, and the second reaction is also completed (see FIG. 4C). When the second reaction is completed, the component to be analyzed can be measured by a change in physical quantities such as optical characteristics and electrical characteristics. In the present embodiment, the optical characteristic of the body fluid sample 5 is changed by the second reaction, and the component to be analyzed can be measured by measuring the change of the optical characteristic in the reaction chamber 4. Yes.

(Example)
Here, in order to confirm the effect of the analytical instrument according to the present invention, a sample is analyzed using a specific example of the analytical instrument for body fluid components according to the present embodiment and a comparative example, and the results are compared. went.

The subject of analysis was glucose. A sample with a known glucose concentration added with ascorbic acid as an inhibitor was applied to Examples and Comparative Examples. Specifically, the glucose concentration was common at 100 mg / dL, and the comparison was performed using three types of samples having ascorbic acid concentrations of 0 mg / dL, 10 mg / dL, and 20 mg / dL, respectively. Further, the gap between the reaction chambers 4, that is, the distance between the inner plate surface 11 a of the first sealing plate 11 and the inner plate surface 13 a of the second sealing plate 13 is 150 μm, and the sample is placed in the reaction chamber 4. After the transfer, the first reagent 42 and the second reagent 43 were dissolved, and then the absorbance was measured by irradiating the reaction chamber 4 with light of 630 nm.

Preparation of the first reagent, the second reagent, and the coating layer used in this example is shown below.

(First reagent)
Glucose dehydrogenase 120U / L (during reaction)
Diaphorase 40U / L (during reaction)
PIPES buffer 150 mM (during reaction)
Ascorbate oxidase 1000 U / L (during reaction)
Ethylenediaminetetraacetic acid disodium 0.5% (during reaction)
Sorbitol 2% (during reaction)

(Second reagent and first coating layer forming agent)
Oxidized nicotinamide adenine dinucleotide (β-NAD) 20 mM (during reaction)
Water-soluble tetrazolium salt (WST-8) 40 mM (during reaction)
Sodium alginate 1% (during reaction)

(Second coating layer forming agent)
Calcium chloride 0.5% (during reaction)

In addition, said 2nd reagent and 1st coating layer formation agent were prepared, and it adhered to the 2nd sealing plate 13 (300nL was dripped at a cell part of 1.4mm, and it dried naturally in 10% RH environment). Thereafter, when 150 nL of calcium chloride as the second coating layer forming agent is dropped onto this surface and naturally dried in a 10% RH environment, the surfaces of the second reagent and the first coating layer forming agent are changed to calcium alginate. Thus, a coating layer covering the surface of the second reagent is formed.

(Comparative example)
As a comparative example, what remove | excluded the ascorbate oxidase in the 1st reagent in the said Example and the 2nd coating film formation agent was used.

FIG. 5 and FIG. 6 show the results of comparison between the measured values using the body fluid component analyzer according to the example and the measured values using the body fluid component analyzer according to the comparative example. FIG. 5 is a graph showing changes in absorbance over time in Examples and Comparative Examples. FIG. 6 is a diagram showing changes in absorbance depending on the concentration of ascorbic acid in samples in Examples and Comparative Examples. In addition, the horizontal axis in FIG. 5 shows the elapsed time after a sample flows into the reaction chamber 4, and the vertical axis | shaft has shown the light absorbency. The horizontal axis in FIG. 6 indicates the concentration of ascorbic acid, and the vertical axis indicates the absorbance.

As shown in FIG. 5, in the comparative example, the absorbance begins to rise immediately after the sample flows into the reaction chamber 4, and the absorbance varies depending on the concentration of ascorbic acid. As the absorbance increases, the higher the concentration of ascorbic acid, the higher the absorbance.

In contrast, in the example, the absorbance is substantially unchanged for about 60 seconds after the sample flows into the reaction chamber 4. This is because the second reagent 43 does not dissolve in the sample and the second reaction does not occur due to the presence of the coating layer 44, and during this about 60 seconds, the first reagent 42 dissolves in the sample, and the coating layer 44 It shows that dissolution is progressing gradually. And the coating layer 44 is destroyed, the 2nd reagent 43 begins to melt | dissolve in a sample, and a light absorbency increases as 2nd reaction advances.

In the examples, the change in absorbance with time in the three samples is almost the same regardless of the concentration of ascorbic acid. This indicates that the change in absorbance in the second reaction is not affected because ascorbic acid, which is an inhibitory factor, has already been oxidatively decomposed by the first reaction prior to the second reaction.

FIG. 6 shows the change in absorbance with the concentration of ascorbic acid. For the comparative example, the absorbance after 300 seconds has passed since the sample flowed into the reaction chamber 4, and for the example, the absorbance of the sample after 360 seconds has passed into the reaction chamber 4. In the example, since the dissolution of the second reagent 43 starts after about 60 seconds from the flow of the sample into the reaction chamber 4, in both the comparative example and the example, the dissolution of the second reagent 43 starts approximately. The absorbance after 300 seconds is shown. As shown in the figure, in the comparative example, the absorbance measurement value tended to increase in positive error as the concentration of ascorbic acid increased, but in the examples, the absorbance measurement value was almost constant regardless of the ascorbic acid concentration. It has become. That is, by using the body fluid component analysis instrument according to the present invention, after the first reaction for removing the inhibitory factor is completed, the second reaction in which the change in absorbance occurs can be started, and a highly accurate body fluid component It is shown that the analysis of

DESCRIPTION OF SYMBOLS 1 Analyzing instrument of body fluid component 11 1st sealing plate 12 Ventilation plate 13 2nd sealing plate 2 Sample supply port 21 Through hole 22 Through hole 3 Channel 31 Groove 4 Reaction chamber 41 Through hole 42 First reagent 43 Second reagent 44 Coating layer 5 Body fluid sample

Claims

A sample supply port through which a body fluid sample is supplied;
A flow path extending from the sample supply port;
A reaction chamber communicating with the flow path;
A first reagent provided in the reaction chamber;
A second reagent provided separately from the first reagent, the surface of which is covered with a coating layer;
The coating layer does not dissolve even when contacted only with the body fluid sample,
The first reagent contains a coating layer dissolving agent that dissolves the coating layer.
The coating layer comprises a salt of alginic acid and a divalent metal;
The body fluid component analysis instrument according to claim 1, wherein the coating layer solubilizer comprises a salt of ethylenediaminetetraacetic acid and an alkali metal.
The body fluid component analysis instrument according to claim 2, wherein the coating layer is made of calcium alginate.
The second reagent contains sodium alginate;
The body fluid component analysis instrument according to claim 3, wherein the coating layer is formed by dropping calcium chloride onto the surface of the second reagent.
5. The body fluid component analysis instrument according to claim 1, wherein a wall surface surrounding the reaction chamber is impermeable to water, and at least a part of the wall surface is air permeable.
Impervious and breathable ventilation plates;
A first sealing plate that is disposed so as to abut against one plate surface of the ventilation plate and is impermeable and impermeable to water;
A second sealing plate which is disposed so as to abut against the other plate surface of the ventilation plate, and is impermeable and impermeable.
The ventilation plate has a through-hole penetrating in the thickness direction,
The reaction chamber is partitioned by the through hole, the first sealing plate, and the second sealing plate,
The first reagent is attached to the first sealing plate;
The body fluid component analysis instrument according to any one of claims 1 to 5, wherein the second reagent is attached to the second sealing plate.
The part adjacent to the reaction chamber of the first sealing plate and the second sealing plate has light permeability. The body fluid component analysis instrument according to claim 6.