JPH01202659A - Reagent composition and test piece for detecting component in body fluid - Google Patents

Abstract

PURPOSE:To obtain the results of decision accurately and quickly along with easy manufacture for detecting specified components in a body fluid, especially in blood, by arranging a composition made up of a reagent to detect a specified component in a body fluid and a polyester resin sulfonated as carrier therefor. CONSTITUTION:A composition is made up of a reagent to detect a specified component in a body fluid and a polyester resin sulfonated for a carrier of the reagent. 3-7.5mol.% of all carboxylic acid components in the polyester is an ester forming sulfonic alkali metal compound. This facilitates the manufacture while achieving a higher penetration speed of a sample as the carrier is hydrophilic thereby producing the results of decision accurately and quickly. A test piece to be used can be obtained with ease simply by coating the support with this reagent composition.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a reagent composition for detecting components in body fluids and a test piece using the same.

[Problems to be Solved by the Prior Art and the Invention 3 In recent years, as a means for analyzing components in body fluids, so-called dry case (IJ-I) using test pieces has been developed. In addition to the development of test strips for measuring urinary shield, protein, and pH, new items for measuring urine components have been added, and now semi-quantitative methods using these test strips are being developed. A simple diagnostic method has been established. Furthermore, components in body fluids, especially blood, have come to be measured using test pieces using dry chemistry techniques. In particular, test strips for measuring glucose in the blood are useful in cases such as diabetes where it is necessary to maintain a constant blood glucose concentration.

In order to manufacture such test pieces, conventionally, F paper is used as a carrier, which is impregnated with a reagent for detecting a specific component, and then coated with a polymer compound as a means to remove blood cells, etc. methods have been taken. However, this method has drawbacks such as complicated manufacturing of test pieces and large variations in the test pieces themselves.

JP-A-59.22B166 discloses, as an improvement on this, a method in which a partially crosslinked polymer compound is further coated on top. This coating is said to be advantageous when removing excess samples, such as blood, by wiping, but since hydrophilic proteins or carbohydrates are used here, adhesion phenomena due to re-dissolution are observed, and F, which is a carrier, is used many times during the manufacturing stage.
The manufacturing process has been further increased to process paper.

Therefore, recently, dryke streaks using single-layer or multi-layer film compositions have been developed. Tokuko Showa 49-! l! Publication No. 1800, JP-A-55-1254
No. 53 discloses a single-layer diagnostic agent consisting of a water-resistant film in which reagents are uniformly distributed. The diagnostic agent contains a film-forming component and a reagent component that are soluble in organic solvents such as ethyl cellulose, acetyl cellulose, polyvinyl acetate, polyvinyl propionate, polyvinyl butyl acetal, or latex, or are dispersible in water. It is obtained by mixing in a dispersed state, applying it to a support, and drying it. If necessary, inorganic or organic insoluble fine particles can be used as a film release agent.

The test pieces obtained by this method, when blood cells are removed after reacting with blood for a certain period of time, can obtain a color tone that is problematic due to the concentration of the components, but it does not use hydrophobic film-forming components to begin with. Therefore, it took a long time for the reaction to occur, and it also took a long time for the coloring to become stable. Furthermore, even when dispersing film-forming components and reagent components, it is difficult to obtain a uniform dispersion state.

JP-A-62-19454 discloses a single transparent reagent carrier layer. The reagent carrier layer consists of a water-soluble or water-swellable component and an essentially insoluble film-forming component, and the film-forming component is a high molecular weight polymer such as cellulose ester, polyvinyl acetate, polyamide, or a nonionic component. Or using an ionic polyurethane dispersion. The feature here is that the mixing ratio of the water-swellable component and the film-forming component is kept within a certain range.
This ratio is between 1:1 and 1:50, preferably between 5 and 1:10.
It is said that Therefore, in order to form the reagent carrier layer, the film-forming component alone is insufficient because it is essentially insoluble in itself, and a water-soluble or water-swellable component is essential.

In addition, since an essentially water-insoluble component and a water-swellable component are mixed, it is necessary to use the same solvent or diluent for both, and it is difficult to obtain a uniform dispersion state and requires manufacturing technology. It is.

Regarding multilayer film compositions, Japanese Patent Publication No. 56-45
Publication No. 599, Publication No. 58-18628, Japanese Unexamined Patent Application Publication No. 1973
It is disclosed in Japanese Patent No. 6-24576 and Japanese Patent No. 57-66559. These structures generally consist of a deployment layer,
It is made by laminating a reagent layer and a detection layer on a support,
A body fluid, particularly serum, is dropped onto the developing layer, and after reaction for a certain period of time, the color development of the detection layer is detected through a transparent support.

Therefore, a dedicated reading device is required for these, and it is difficult to imagine them as a simple means of measurement as described above. Additionally, special equipment is required to laminate the film.
In addition to being difficult to manufacture, it is also expensive in terms of cost.

The present invention is intended to solve the problems in the prior art described above.

A first object of the present invention is to provide a reagent composition for detecting a specific component in body fluids, particularly blood, which is easy to manufacture and allows accurate and rapid determination results.

A second object of the present invention is that the reagent composition described above can be manufactured without using complicated manufacturing processes or manufacturing equipment;
The objective is to provide a test piece that is inexpensive, easy to use, and highly reliable.

[Means to solve the problem]

As a result of intensive research in order to obtain a recombinant and a test piece that meet these conditions, the present inventors have developed a composition in which a reagent for detecting specific components in body fluids is mixed with a sulfonated polyester resin; It was found that the test piece obtained after coating the same on a support and drying at a constant temperature had the above-mentioned performance, leading to the completion of the present invention.

That is, the reagent composition for detecting components in body fluids of the present invention is characterized by comprising a reagent for detecting a specific component in body fluids and a sulfonated polyester resin as a carrier for the reagent. .

Generally, polymer resins have been dissolved in organic solvents and used as raw materials for paints, inks, films, adhesives, etc. However, in recent years, polymer resins have been used as raw materials for paints, inks, films, adhesives, etc.; , research has been conducted on water solubilization as a safer direction. A common way to make a resin water-soluble is to introduce a hydrophilic substituent into the resin skeleton, usually in the form of a salt of the hydrophilic group. It can be divided into two forms: anionic and cationic. It is possible to obtain an aqueous solution state of these water-soluble polymer resins without using an emulsifier, and thus a purely aqueous polymer resin liquid without using an organic solvent can be produced.

Specific measures for making the resin hydrophilic include a method of using raw materials that have a salt of a hydrophilic group from the beginning, for example, a method of obtaining a resin by copolymerizing a dicarboxylic acid such as 5-sulfoisophthalic acid sodium salt; There is a method in which a substituent having the ability to form a salt is introduced in advance and then made hydrophilic, for example, a method in which residual carboxylic acid in a polyester having a high acid value is neutralized with an alkali. Furthermore, there is also a method of introducing hydrophilic groups by a reaction not directly related to increasing the molecular weight, such as adding an inorganic sulfate to a polymer resin having unsaturated bonds.

Surprisingly, among such water-soluble polymer resins developed as base materials for paints and inks, i? The sulfonated polyester resin is mixed with a reagent that detects specific components in body fluids, coated at a certain thickness, and then dried at a certain temperature to form a film. It has been discovered that it has the ability to remove polymeric substances such as red blood cells from body fluids, and can also penetrate and react with target components.

Examples of the sulfonated polyester resin used in the present invention include FINETE manufactured by Dainippon Ink and Chemicals.
X-ES (trade name, Finetex-ES) is particularly good.

The resin contains, for example, 679 parts of dimethyl terephthalate, 225 parts of dimethyl isophthalate, 104 parts of dimethyl sodium 5-sulfoisophthalate, 496 parts of ethylene glycol, 212 parts of diethylene glycol, and zinc acetate n.
The resin can be obtained by mixing 3 parts of antimony trichloride and 15 parts of antimony trichloride, reacting by heating to 170 to 200°C under a nitrogen stream, and neutralizing the resulting polyester copolymer with aqueous ammonia. A major feature of the polyester is that 5 to 7.5 moles of the total carboxylic acid component in the polyester is composed of an ester-forming alkali metal sulfonate compound.

The content rate of the alkali metal sulfonate compound is an important factor between the water solubilization of the polyester resin and the strength of the film after drying, and if this rate is too high or too low, the desired performance will not be achieved. I can't get it.

Therefore, since this reagent composition uses the polyester resin with hydrophilic groups as a base material, the penetration rate is fast when it comes into contact with the specimen, and therefore the reaction time is longer than that of conventional essentially insoluble films. This is much shorter than when using formable polymer resin. However, on the other hand, because the original backbone of this reagent composition is polyester, it will not completely redissolve upon contact with the analyte, and after the reaction the surface will be the hole through which the analyte passed and the hole where the reagent was dissolved. Although it penetrates through the support, the original resin skeleton remains and will not peel off from the support.

A mixture of sulfonated polyester resin and reagent is used as a test piece by coating it on a support. Particularly preferred are water-insoluble polymeric compounds such as polychloride, polyethylene terephthalate, polycarbonate, polypropylene, and polystyrene in the form of a film, sheet, or rod.

In this way, a mixture of a reagent for detecting a specific component in body fluids and a sulfonated polyester resin is applied onto a support at a constant thickness, and after drying, the resulting reagent composition is supported. When a test piece is prepared by cutting the supporting material into an appropriate size, a body fluid, especially blood, is placed on it, reacted for a certain period of time, and then blood cell components are removed using an appropriate method. This means that color can be obtained.

〔Example〕

The invention will be explained in further detail in the following examples. Note that the present invention is not limited to the following examples.

Example t Production of a test strip for measuring glucose in blood In order to examine the effectiveness of a test strip using a reagent composition containing a sulfonated polyester resin of the present invention, a test strip for measuring glucose in blood was prepared. A test piece was prepared and compared with a test piece using a reagent composition containing a known resin.

(Reagent composition) Reagent components Glucose oxidase 48,000 IU Peroxidase 63,800 IUO-tolidine dihydrochloride 290 ■ 2,7-Diamitsufluorene
Dihydrochloride 320■a5M phosphate buffer (pH 7
fJ) 40ml ethanol
20au distilled water 30m Film forming component 857■FINET
EX-ES (sulfonated polyester resin) ■Polypropionate vinyl ■Anionic polyurethane dispersion After thoroughly mixing the above reagent components and film-forming component ■ to prepare reagent composition 1 of the present invention, as shown in FIG. As shown, the width is 10112I on a support 2 made of a true white polycarbonate film with a length of 80rIaR% and a width of 300mm! 1 thickness 3
Reagent composition 1 was applied laterally using an appropriate coating method to a thickness of 0.00 μm, followed by drying in a hot air dryer at 80° C. for 10 minutes. This was cut into a width of 5 mm in the longitudinal direction to obtain a test piece 5 (test piece ■). Similarly, test pieces 1 and 0 were obtained using film-forming components 1 and 2.

Blood was dropped onto the test piece 3 and wiped off with absorbent cotton after exactly 30 seconds. The results are shown in Table 1 below.

Table 1 Next, in order to examine the reactivity of these test pieces in more detail, blood containing 100, 200, 300, 500, 800 η/dt of glucose was prepared and the coloring obtained by performing the same procedure. compared.

■! As the temperature increased, the blue color became deeper, and a color difference was clearly observed.

■ You can see some color difference, but the colors are pale overall.

■ The color is pale overall and the color difference is not clear.

The reflectance of this color was immediately measured using a spectrophotometric colorimeter (Murakami Color Research Institute CMS-1200) at a wavelength of BO O nm. A calibration curve as shown in FIG. 2 was obtained from the obtained reflectance and the glucose concentration measured using a glucose analyzer (YSI Glucose Analyzer Model 23A).

In the figure, the vertical axis represents the reflectance at 600 nm, and the horizontal axis represents
Represents the glucose concentration in the blood.

As mentioned above, all of the K test pieces were good at removing blood cells, but in terms of reactivity, the test piece (2) of the present invention was found to be better than the other test pieces. In other words, test piece ■ or 0
Since the film-forming components are essentially water-insoluble, the permeability of the specimen cannot be improved without fine particles and water-swellable components as film release agents, and these components are therefore essential. However, in the test piece of the present invention, since the resin itself has water solubility, the specimen penetrates easily, and there is no need for special measures to improve permeability.

Example 2 Production of a test piece for measuring lactic acid in blood In order to create a test piece for measuring lactic acid in blood, a reagent composition having the following composition was prepared.

Lactate oxidase 21,000 IU Peroxidase 37,000 IU 4-aminoantivirine 244 ■ 1M Tris-HCl buffer (pH 7)
,5) 25v? Distilled water 30 - After thoroughly mixing the above components, FINE TEX-ES 50 was applied onto a white polyvinyl chloride film in the same manner as in Example 1, except that the coating thickness fzr was 450 μm, and then A test piece was obtained by drying in a hot air dryer at 70°C for 15 minutes. When blood is dropped onto this test piece and wiped off, a purple coloration corresponding to the lactic acid concentration is obtained.

〔Effect of the invention〕

As mentioned above, the reagent composition for detecting components in body fluids of the present invention includes:
Since sulfonated polyester resin is used as a carrier for reagents used to detect specific components in body fluids, it is easy to manufacture, and since the carrier is hydrophilic, the sample penetrates quickly and the determination results are accurate. and can be obtained quickly.

In addition, the test piece of the present invention can be easily obtained by simply applying the above-mentioned reagent composition onto a support, is inexpensive, has a simple structure, and can be easily modified in various ways, and is easy to use and reliable. is high.

[Brief explanation of the drawing]

Figure 1 is an explanatory diagram of the manufacturing process of one embodiment of the test piece for detecting components in body fluids of the present invention. Figure 2 shows the calibration curve obtained using the test pieces (■ to C) of Example 1. It is a diagram. In the figure, 1... Reagent composition 2... Support 3... Test piece patent applicant Eiken Chemical Co., Ltd. (and 2 others) Mijin: 1. +! !

Claims (3)

[Claims] (1) A reagent composition for detecting a component in a body fluid, comprising a reagent for detecting a specific component in a body fluid, and a sulfonated polyester resin as a carrier for the reagent. (2) The sulfone group in the sulfonated polyester resin is contained in an amount of 5 to 7.5 mol% based on the total carboxylic acid component as an ester-forming alkali metal sulfonate compound. reagent composition. (3) A test piece for detecting components in body fluids, comprising a support coated with the reagent composition according to claim 1 or 2.