JPH06341986A - Testing tool having heating means - Google Patents

Abstract

PURPOSE:To carry out measurement at high sensitivity and to shorten the measuring time without using an expensive complex equipment and under no influence of measuring environment by providing a reagent layer and a heating layer in a layered form composed of carriers having adsorbed a detecting reagent component and a heating reagent component. CONSTITUTION:A heating layer 3, a separating layer 2 and a usual reagent layer 1 are made to adhere laminatedly to a supporting body 4 in order from the lower side. The heating layer 3 needs to use such a heating principle as it is formed by making a carrier, namely a filter paper and a dish cloth, adsorb a heating reagent, and generates heat only by coming into contact with an aqueous solution to be detected to attain temperature suitable for detecting reaction in the reagent layer 1, and moreover heating reaction is not influenced by a component in the detecting solution. Calcium oxide or its mixture with organic acid or inorganic acid is used as the heating reagent. The separating layer 2 is provided so that the heating reagent may not mix with a detecting reagent in the reagent layer and not disturb the reaction of both the reagents, and a material which is not water-permeable and has a certain degree of heat resistance, for instance, polyethylene sheet having thickness not to disturb heat conduction, is used as a material suitable for the separating layer.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a test device used for measuring a specific component in a body fluid such as blood or urine, which is used for speeding up the measurement and increasing the sensitivity.

[0002]

2. Description of the Related Art In recent years, dry chemistry methods have become widespread, with the trend of accelerating clinical tests and simplifying operations used for medical diagnosis. The dry chemistry method is a substance to be detected by contacting a reagent necessary for diagnosis with a non-measurement solution such as blood or urine, using a test device in which an adsorptive carrier such as filter paper or cloth is supported. When present, a color reaction occurs and the presence of the substance is easily recognized.

Examples of such a test device include tests for occult blood in blood, urine and feces, tests for leukocytes in urine, ketone bodies, urobilinogen, nitrite ascorbic acid, blood, glucose in urine, protein, Bilirubin,
pH, ammonia, amylase test, cholesterol in blood, triglyceride, uric acid, GOT,
Some are for ion inspection of GPT, urea nitrogen, hemoglobin, sodium / potassium, etc.

Although the measuring principle of these test tools varies widely depending on the measurement item, various measures are generally taken to shorten the detected concentration and obtain a more accurate result. For example, in the reagent composition, the material and shape of the test device, the method of applying the sample, the method of reading the color change, and the like, many measures have been made so that the test device has the best performance.

However, the reduction of the detection speed and the improvement of the detection sensitivity have already reached the limit of some measurement items by these methods, so that the satisfactory accuracy and the measurement time have not been obtained yet, or the performance is further improved. There are many measurement items that need to be improved.

As one of the means for solving these problems, there is a method of heating the detection reaction to a constant temperature. The detection reaction includes an enzymatic reaction and a chemical reaction, but in any reaction, the reaction temperature often affects the reaction rate. In particular, the enzymatic reaction is highly dependent on the reaction temperature and may be significantly affected by the measurement environment such as the temperature in the laboratory. Although most of the reaction temperatures of most enzymes are around 37 ° C., which is the living body temperature, the detection reaction is usually performed at room temperature, so that a series of reactions may proceed under non-optimal reaction conditions. It is suggested.

Therefore, by performing these detection reactions by heating them to a constant temperature, the detection reactions proceed under more suitable conditions, and as a result, the detection speed can be shortened and the sensitivity can be improved, and the measurement environment such as temperature can be improved. It is possible to measure without being affected by. In order to achieve this means, conventionally, a heating device is attached to a measuring device for performing a detection reaction in a constant temperature reaction tank, reading a color change of a test device, and continuously performing measurement, A method has been used in which the test device is heated during the reaction.

However, it is impossible or very difficult to use this method in the case of a simple measurement in a home or the like where equipment such as a constant temperature bath cannot be used or a measurement by visual judgment without the use of measurement equipment.

[0009]

SUMMARY OF THE INVENTION The present invention does not use expensive and complicated equipment, is not affected by the measurement environment,
The present invention provides a test device having high sensitivity and shortening the measurement time.

[0010]

The above object can be achieved by the present invention described below.

A reagent layer composed of a carrier in which a detection reagent component is adsorbed on a support and a heat generation layer composed of a carrier in which a heat generating reagent component is adsorbed are layered, or a mixed layer of the detection reagent component and the heat generating reagent component Is provided with a test tool.

[0012] The test device according to [1], wherein the exothermic layer is composed of a composition that causes an exothermic reaction by reacting with moisture in a non-measurement substance.

The test device according to (1), wherein a separation layer is provided between the reagent layer and the exothermic layer when the detection reagent component and the exothermic reagent component interact with each other.

The test device according to claim 1, wherein a temperature uniformizing layer for uniformizing the temperature distribution of the reagent layer is provided between the reagent layer and the heat generating layer.

[0015] The test device according to [1], wherein the separation layer according to [1] is the temperature average unification layer described above.

The test device according to the present invention can be constructed by newly providing a heat generating layer on the conventionally used test device. As the shape, as shown in FIG. 1, a heating layer may be laminated on a conventional reagent layer, or may be provided.
As shown in FIG. 2, it may be provided on the back side via a support.

In either case, a separation layer is provided between the reagent layer and the exothermic layer so that the exothermic reagent does not mix with the detection reagent and hinder the reaction of both, so that mutual liquid exchange can be performed when the sample solution is applied. It is desirable not to happen. It is also possible that the support itself also serves as a separation layer, as shown in FIG. 2 in which two layers are located via the support.

Further, since the heat of the exothermic layer is quickly and evenly transferred to the reagent layer, the exothermic layer becomes even more effective by providing the temperature uniformizing layer made of a substance having high thermal conductivity. Depending on the thickness, shape, and components of the reagent layer, the heat conduction speed of the heat generating layer may be slow, and the heat transfer to the reagent layer may be uneven, which may cause uneven coloring. These can be avoided by providing a temperature uniformizing layer.

As shown in FIG. 3, the temperature uniformizing layer is provided between the reagent layer and the exothermic layer in the form of also serving as a separation layer, or as shown in FIG.
When the support also serves as the separation layer as shown in, it may be provided between the support and the heat generating layer.

The exothermic layer rapidly generates heat only when it contacts the aqueous solution of the sample, and the exothermic temperature becomes a temperature suitable for the detection reaction in the reagent layer, and the exothermic reaction is not affected by the components in the sample solution. Such a heat generation principle must be used.

The exothermic reagent is applied to the test device by a method of adsorbing it on a carrier such as filter paper or cloth, or by dispersing the solid reagent in a suitable binder to form a layer. As the exothermic reagent, calcium oxide, a mixture of calcium oxide and an organic acid or an inorganic acid, a mixture of alkali metal sulfide and silica or alumina, iron oxide, or a mixture of iron oxide and an inorganic salt can be used.

Whichever principle is used, in order to prevent an exothermic reaction from being brought into contact with the aqueous solution of the sample and not to cause an exothermic reaction during storage or contact with air, in some cases, it may react with air or moisture in the air. In order to avoid contact with the above, a means for providing a coating with a water-soluble substance on the heating layer is taken. This coating component is preferably a substance that quickly dissolves in contact with the sample aqueous solution. For example, polyvinyl alcohol, polyvinylpyrrolidone, carboxymethyl cellulose, polyethylene glycol are used.

Further, depending on the heat generation principle, an efficient heat generation reaction may not occur even if the amount of water supplied is too large, and a sufficient temperature may not be obtained. In such a case, it is necessary to devise such that a part of the sample solution is supplied to the exothermic reagent, and this can be achieved by, for example, providing a porous hydrophobic film or mesh on the surface of the exothermic layer.

Any material can be used as the material of the separation layer as long as it is impermeable to water and has heat resistance to some extent. Specifically, a sheet of polyethylene, polypropylene or vinyl chloride is used. Its thickness must be such that it does not interfere with heat conduction, and is preferably 10 to 30.
The one with μm is used.

The temperature uniformizing layer is usually made of a material having a high thermal conductivity such as a thin metal plate. Specifically, aluminum foil or copper foil is preferable, and its thickness is preferably 10 to 60 μm.

These layers are assembled in a test tool form by means such as adhesion using a double-sided tape or an adhesive, fixing each layer as shown in FIG. 5 to a holder in a laminated state. In particular, in the case of a multi-layered test device, which is often found in blood test papers, a method of collectively fixing the layers necessary for detection with a holder is adopted. When a double-sided tape is used for adhesion, the double-sided tape can also serve as the separation layer.

In order to retain the components of each layer on a carrier such as filter paper or cloth, each component is dissolved in an appropriate solvent, impregnated with the carrier, and then dried to remove the solvent. Next, examples will be shown to describe the test device of the present invention in more detail.

[0028]

[Example 1] Effect of temperature on leukocyte test paper detection reaction Filter paper (Advantech, No. 514A) 200 m
M Borax-hydrochloric acid buffer solution (pH = 8.0)
It was air-dried at 60 ° C. for 50 minutes. Furthermore, this filter paper 1
0 mM 3- [Np- (toluenesulfonyl) -L-
Alanyloxy] indole, 5 mM 2-methoxy-
4-Morpholinobenzenediazonium chloride zinc chloride double salt was impregnated with an acetone solution containing 2% of n-decanol, and air-dried at 40 ° C. for 20 minutes to form a reagent layer. The obtained test piece was cut into a 6 × 6 mm square and fixed on a polystyrene support with a double-sided tape.

A sample solution was dropped on the obtained test paper and reacted for 2 minutes in a thermostat at a predetermined temperature, and then the color change on the surface of the test paper was observed by measuring the reflection absorbance at 545 nm.
The measurement was performed using a spectrophotometer MCPD-200 manufactured by Otsuka Electronics Co., Ltd. As a sample, a solution of a granulocyte fraction isolated from human peripheral blood by a conventional method in an isotonic phosphate buffer solution to a concentration of 200 / μl was used, and as a control, cells were not included. Tonic phosphate buffer was used. The result is shown in Fig. 6.
Shown in.

From FIG. 1, the reaction carried out at around 20 ° C. and 40 ° C.
It is clear that there is a difference of 0.2 in the absorbance value when comparing the cases of heating. 0.2 for visual judgment
It is clear that the increase in the absorbance makes the determination considerably easier, and the results of the present Example were also easy to read by visual determination.

[0031]

Example 2 Preparation of white blood cell detection test tool Filter paper (Advantech No. 514A) 200 m
M Borax-hydrochloric acid buffer solution (pH = 8.0)
It was air-dried at 60 ° C. for 50 minutes. Furthermore, this filter paper 1
0 mM 3- [Np- (toluenesulfonyl) -L-
Alanyloxy] indole, 5 mM 2-methoxy-
4-Morpholinobenzenediazonium chloride zinc chloride double salt was impregnated with an acetone solution containing 2% of n-decanol, and air-dried at 40 ° C. for 20 minutes to form a reagent layer.

Filter paper (Advantech No. 462)
Was impregnated with a 5% citric acid aqueous solution and dried by ventilation at 70 ° C. for 80 minutes. Further, this filter paper was impregnated with an anhydrous chloroform solution containing 1% polyvinylpyrrolidone (K-30) in which 10% calcium oxide powder (300 mesh or less) was suspended, while stirring well, and the temperature was 40 ° C. and the humidity was 5% or less. Under the conditions described above, it was dried by ventilation for 15 minutes to form a heat generating layer. At this time,
20 μm thick vinyl chloride sheet as a separation layer, thickness 25 μm
m aluminum foil was used for the temperature homogenizing layer.

These layers were cut into a 6 × 6 mm square to assemble the following test device according to the present invention.

(A) Thickness of 0.
As shown in FIG. 1, the exothermic layer, the separation layer, and the reagent layer were adhered to the end of a 2 mm polystyrene support in this order from the bottom.

(B) As shown in FIG. 3, a heat generating layer, a temperature uniformizing layer (also serving as a separation layer), and a reagent layer were adhered in this order from the bottom to the end of the support.

(C) As shown in FIG. 2, a reagent layer was adhered to the end of the support, and a heat generating layer was adhered to the same position on the back side of the support.

(D) As shown in FIG. 4, a reagent layer was adhered to the end of the support, and a temperature equalizing layer and a heat generating layer were adhered to the back side of the support from below.

(E) The reagent layer, the temperature uniformizing layer and the exothermic layer were assembled and fixed in a holder as shown in FIG.

(F) Only the reagent layer was adhered to the above support (for performance comparison).

[0040]

Example 3 Evaluation of Test Tool After dropping the sample solution into each test tool prepared in Example 2, the change in color on the surface of the test paper was observed by measuring the reflection absorbance at 545 nm. Measurement is spectrophotometer MCPD made by Otsuka Electronics Co., Ltd.
It was performed using -200. As a sample, a solution of a granulocyte fraction isolated from human peripheral blood by a conventional method in an isotonic phosphate buffer solution to a known concentration was used. Acid buffer was used. The results are shown in Table 1.

[0041]

[Table 1]

As is clear from Table 1, the test tool having the heat generating means has a faster coloration speed. If you have a heating means,
Reached equivalent absorbance in about half the time without it,
It is clear that the measurement time can be shortened.

[0043]

EFFECT OF THE INVENTION The test device according to the present invention does not use expensive and complicated equipment, is not affected by the measuring environment, has high sensitivity, and can shorten the measuring time.

[Brief description of drawings]

FIG. 1 is a schematic sectional view of an example of a test tool according to the present invention.

FIG. 2 is a schematic sectional view of an example of a test device according to the present invention.

FIG. 3 is a schematic sectional view of an example of a test device according to the present invention.

FIG. 4 is a schematic sectional view of an example of a test device according to the present invention.

FIG. 5 is a schematic sectional view of an example of a test device according to the present invention.

FIG. 6 is a graph showing the influence of temperature on the leukocyte test strip detection reaction.

[Explanation of symbols]

 1 Reagent Layer 2 Separation Layer 3 Exothermic Layer 4 Support 5 Support (Separation Layer) 6 Temperature Uniformization Layer (Separation Layer) 7 Temperature Uniformization Layer 8 Holder

─────────────────────────────────────────────────── ───

[Procedure amendment]

[Submission date] July 5, 1994

[Procedure Amendment 2]

[Document name to be corrected] Drawing

[Correction target item name] All drawings

[Correction method] Change

[Correction content]

[Figure 1]

[Fig. 2]

[Figure 3]

[Figure 4]

[Figure 5]

[Figure 6]

Claims (5)

[Claims] 1. A reagent layer composed of a carrier having a detection reagent component adsorbed on a support and a heat generation layer composed of a carrier having an exothermic reagent component adsorbed in layers, or the detection reagent component and the exothermic reagent component. A test tool provided with a mixed layer of. 2. The test device according to claim 1, wherein the exothermic layer is composed of a composition that causes an exothermic reaction by reacting with water in a non-measurement substance. 3. The test device according to claim 1, wherein a separation layer is provided between the reagent layer and the exothermic layer when the detection reagent component and the exothermic reagent component interact with each other. . 4. The test device according to claim 1, wherein a temperature uniformizing layer for uniformizing the temperature distribution of the reagent layer is provided between the reagent layer and the heat generating layer. 5. The test device according to claim 1, wherein the separation layer according to claim 3 is the temperature-averaged unification layer according to claim 4.