JP7788134B2 - Solvent-containing substance test kit - Google Patents

Description

This invention relates to a solvent-containing substance testing kit, and more specifically to a solvent-containing substance testing kit that can easily test for target substances (test substances) such as biological components and drugs contained in a developing solvent while preventing leakage of biological components.

For example, a vertical immunological testing device (solvent-containing substance testing kit) that easily detects target substances (such as antigens or antibodies) contained in specimens (developing solvents) such as blood, serum, and urine collected from a living body is known, which uses an immunochromatography method that utilizes an antigen-antibody reaction (see, for example, Patent Document 1).
This vertical immunological test device has a transparent test tube-like bottle (solvent container, e.g., Patent Document 2) into which a sample is placed, and a strip-shaped developing medium (chromatography medium) that is longer than the bottle and can be infused by capillary action. From its bottom to its top, the strip-shaped developing medium is divided into a sample immersion zone (solvent immersion zone), a labeled reagent zone containing a labeled reagent, and a detection zone where a target substance contained in the sample is detected.

During testing, the strip-shaped developing medium is inserted into a bottle containing a sample, with each zone positioned within the bottle, and the sample immersion zone is immersed in the sample. This causes the sample to develop toward the top of the strip-shaped developing medium, and in the labeled reagent zone, the target substance in the sample binds to the labeled substance, forming a complex. The complex in the sample is then captured by the capture substance in the detection zone, and by observing whether the labeled substance develops color here, it is determined whether the sample is positive, meaning it contains the target substance, or negative, meaning it does not.

Japanese Patent Application Laid-Open No. 2010-122205 JP 2013-167509 A

In the immunological test device disclosed in Patent Document 1, a thin, stick-like strip-shaped developing medium is inserted into a bottle containing the sample, and then the sample is tested. As a result, the following four problems arise.
(1) There was a gap between the edge of the bottle opening and the strip-shaped developing medium at the opening of the bottle. Therefore, if the bottle was accidentally knocked over, there was a risk that the contents (the specimen) would leak and infectious substances would be scattered around.
(2) Furthermore, during testing, dust, bacteria, viruses, and other floating particles could easily enter the bottle through gaps in the bottle opening, which could affect the test results.
(3) Generally, there are products that only have a thin stick, but during testing, the position of the colored test line, control line, etc. in the detection zone determines whether the result is positive or the end of the reaction, but it is difficult to physically provide instructions on the test device to identify the respective colored positions. Therefore, in the case of test devices that measure multiple items simultaneously, there is a risk of misjudgment if the judgment is based solely on the position of the colored lines.

Furthermore, for example, if the sample is highly viscous and contains impurities, when a stick-shaped strip of developing medium is inserted into a bottle and the sample immersion zone is immersed in the sample, the impurities may adhere to the sample immersion zone, preventing the sample from being infused by capillary action.

This invention was developed in consideration of the problems with the prior art described above, and aims to provide a solvent-containing substance testing kit that can prevent infectious substances contained in the specimen (the contents) from being dispersed to the surrounding area due to leakage of test liquid from the test container during testing, can prevent floating substances from entering the test container during testing, and furthermore, makes it easier to visually check test results, thereby increasing the accuracy of the determination.

The invention described in claim 1 is a solvent-containing substance testing kit comprising: a solvent container having an opening and containing a developing solvent containing a target substance to be detected at its bottom; a vertical cassette device attached through the opening of the solvent container for testing the target substance contained in the developing solvent; and a covering container fitted to the solvent container to seal the opening and covering and sealing the cassette device. The cassette device comprises a vertically elongated strip-shaped developing medium capable of infusing the developing solvent by capillary action, and a vertically elongated medium storage case capable of storing the strip-shaped developing medium. The strip-shaped developing medium has a solvent immersion zone immersed in the developing solvent and a labeling reagent containing a labeling reagent for labeling the target substance. A labeled reagent zone having a target substance and a detection zone containing a capture substance that captures the target substance are arranged sequentially from the bottom to the top of the strip-shaped developing medium, and the medium storage case has a solvent immersion zone holder that holds the solvent immersion zone of the strip-shaped developing medium in an exposed state, a labeled reagent zone covering that covers the labeled reagent zone of the strip-shaped developing medium, and a determination cassette unit that has a determination window that exposes the detection zone of the strip-shaped developing medium and stores the upper part of the strip-shaped developing medium, arranged sequentially from top to bottom.After the cassette device is inserted into the solvent container, it fits into the solvent container to seal the opening and cover the cassette device.

The solvent-containing substance test kit referred to here is a test device (kit) that can easily test for various target substances contained in a developing solvent. For example, a kit including an immunological test tool can be used.
An immunological testing device is a device for simple immunological testing of clinical specimens using the immunochromatography method, which utilizes an antigen-antibody reaction. The immunological test may be an antigen detection system or an antibody detection system.
The developing solvent here refers to a solution of only the specimen containing the target substance, or a mixture of the specimen and a specimen extract.
The type of specimen is not limited, and examples include blood such as whole blood, plasma, and serum, body fluids such as urine, saliva, synovial fluid, and bone marrow fluid, as well as sputum, pharyngeal and nasal swabs, nasopharyngeal swabs, nasal blows, nasal aspirates, and lung lavage fluid.
Examples of sample extracts that can be used include surfactants for solubilizing viruses and the like, buffers for improving the spreading properties in immunochromatography, and buffers for reducing the viscosity of samples such as mucin. A composite buffer solution that combines multiple of these buffers can also be used. Buffers for solubilizing viruses and the like and buffers for improving the spreading properties in immunochromatography contain nonionic surfactants, anionic surfactants, and cationic surfactants. Buffers for reducing the viscosity of samples such as mucin contain lysozyme, hyaluronidase, glucosidase, and the like.

There are no limitations on the material of the solvent container and the covering container, and for example, various synthetic resins and various metals can be used.
The solvent container and the covering container may have any shape, such as a test tube or a rectangular box.
The solvent container/covering container referred to here may be, for example, a test tube-shaped bottle made of soft synthetic resin, or a bottle-shaped container that does not easily deform when squeezed. Specifically, for example, when processing a biological component (specimen) collected with a cotton swab or the like, a test tube-shaped bottle made of soft synthetic resin may be used to extract the specimen using a specimen processing solution by squeezing the outside of the bottle with fingers. Furthermore, in the case of a bottle-shaped container that does not easily deform, the squeeze-less bottle shown in Patent Document 2, which extracts a specimen from a cotton swab using an extraction assisting member, is even more suitable because it eliminates finger fatigue caused by the squeezing operation. It is necessary that the covering container of the solvent-containing substance testing kit of the present invention be structured so that it can cover the entire cassette device by fitting into the solvent container so as to seal the opening of the solvent container.

The type of target substance (capture substance) is arbitrary. For example, when the developing solvent is the sample, antigens, antibodies, hormones, hormone receptors, lectins, lectin-binding carbohydrates, drugs or their metabolites, drug receptors, nucleic acids, and fragments thereof can be used. Specific examples include cells of bacteria, protozoa, fungi, etc., viruses, proteins, polysaccharides, etc. More specific examples include various viruses such as influenza virus, parainfluenza virus, respiratory syncytial virus, human metapneumovirus, Mycoplasma pneumoniae, rotavirus, calcivirus, coronavirus, adenovirus, enterovirus, herpes virus, human immunodeficiency virus, and hepatitis virus, as well as cells of Escherichia coli, Staphylococcus aureus, Streptococcus pneumoniae, Streptococcus spyogenes, Mycoplasma pneumoniae, and malaria parasites, pathogens of various diseases such as digestive system diseases, central nervous system diseases, and hemorrhagic fever, and metabolic products of pathogens.

The cassette device can be any device that has a strip-shaped developing medium capable of testing the target substance in the developing solvent, and a cassette case that stores the strip-shaped developing medium and is completely covered when the covering container is fitted after it is attached to the solvent container.
Any material can be used for the strip-shaped developing medium. For example, nitrocellulose, plastic, nonwoven fabric, filter paper, etc. can be used. Of these, nitrocellulose is preferred because it is wettable to liquids and does not substantially absorb the applied liquid. This strip-shaped developing medium is used as a carrier to immobilize antibodies and antigens in the detection zone.

The strip-shaped developing medium can be configured, for example, with a sample pad placed in the solvent immersion zone, a conjugate pad with immobilized labeled reagent placed in the labeled reagent zone, a nitrocellulose membrane with immobilized capture substance placed in the detection zone, and a water-absorbent material (including absorbent paper) placed above the detection zone. In this case, the developing solvent (e.g., a specimen) immersed in the sample pad in the solvent immersion zone is developed toward the top of the strip-shaped developing medium. As it passes through the conjugate pad in the labeled reagent zone, the target substance binds to the labeled reagent, forming a target substance-labeled reagent complex. The developing solvent containing this complex then reaches the detection zone, where it is captured by the capture substance immobilized on the nitrocellulose membrane, forming an immune complex of target substance-labeled reagent-capture substance. After capture, the used developing solvent is absorbed by an absorbent material such as filter paper or a sponge. This prevents the developing solvent from flowing back through the strip-shaped developing medium.

The solvent immersion zone is a region that is disposed at the lower end of the strip-shaped developing medium and is immersed in the specimen placed at the bottom of the solvent container.
The labeled reagent zone is located above the solvent immersion zone of the strip-shaped developing medium and is a region containing a labeled reagent.
The labeling reagent may be, for example, a complex formed by binding an antigen or antibody to a labeling substance such as colored latex, metal colloid (gold colloid, silver colloid, bronze colloid, iron colloid, etc.), colored cellulose particles, fluorescent cellulose particles, colored silica particles, fluorescent silica particles, etc. Alternatively, fluorescent substances or chemiluminescent substances may be used as labeling substances, or various enzyme-labeling reagents may be used.

The detection zone is located above the labeled reagent zone of the strip-shaped developing medium, and is an area where a capture substance that captures the target substance that has bound to the labeled reagent obtained in the labeled reagent zone is immobilized.
The capture substance is changed appropriately depending on the target substance in the developing solvent. If the target substance is an antibody, its antigen will be the capture substance, and vice versa.
Examples of the structure of the immune complex captured in the detection zone (target substance-labeled reagent-capture substance) include (1) solid-phase antibody-antigen in the specimen-labeled antibody, (2) solid-phase antigen-antibody in the specimen-labeled antibody, and (3) solid-phase antigen-antibody in the specimen-labeled antigen. The area where such a sandwich structure is formed is colored with a labeling substance such as gold colloid or colored latex in the labeling reagent, and the presence or absence of the target substance can be determined visually or using a camera imaging device.
In addition, in order to confirm the success of the test, a separate capture substance that captures the labeled reagent may be immobilized in the detection zone.

The medium storage case may be made of any material, such as various synthetic resins or metals.
The medium storage case may have any shape as long as it is elongated and can store the strip-shaped developing medium while supporting the solvent immersion zone in an exposed state. For example, it may be stick-shaped.
The solvent immersion zone holding portion is the lower portion of the medium storage case that supports the solvent immersion zone portion located below the strip-shaped developing medium in an exposed state with only the front surface, only the back surface, or both the front and back surfaces exposed.
The shape of the solvent immersion zone holder is not limited, and may be, for example, a stick, a circular tube, a semicircular tube, an elliptical tube, or the like.

The shape of the labeled reagent zone covering portion is not limited as long as it can cover the labeled reagent zone portion of the strip-shaped developing medium. For example, it may be a predetermined tubular shape.
The shape of the determination cassette part may be any shape as long as it has a determination window and can accommodate the upper part of the strip-shaped developing medium. For example, it may be a rectangular box shape.
The reading window must be of a shape and size that does not interfere with the reading of the specimen test.

The invention described in claim 2 is the solvent-containing substance test kit described in claim 1, characterized in that the solvent immersion zone portion of the strip-shaped developing medium is made of a porous material with a thickness of 0.5 mm to 3 mm.

The material of the porous body is not particularly limited as long as it can be formed into a porous body. For example, polyvinyl alcohol, polystyrene, polypropylene, polyethylene, polyurethane, filter paper, glass fiber, regenerated cellulose, etc. can be used. The pore diameter of this porous body is approximately 50 μm to 500 μm. If the pore diameter is less than 50 μm, the pores are narrow, which tends to reduce the filtration performance and cause clogging due to impurities derived from the sample. Furthermore, if the pore diameter exceeds 500 μm, the pores become wide, which significantly reduces the liquid absorption performance due to capillary action. A preferred pore diameter is 80 μm to 300 μm. Within this range, rapid development can be achieved while maintaining the natural filtration performance of the sample.
If the thickness of the porous body is less than 0.5 mm, the liquid absorbed from the solvent immersion zone stagnates, slowing the rate of development to the subsequent labeled reagent zone and resulting in a delay in the determination time. Furthermore, if the thickness exceeds 3 mm, the amount of liquid retained in the porous body increases, preventing sufficient solution from being developed into the subsequent strip-shaped developing medium, resulting in a delay in the determination time and poor development. The preferred thickness of the porous body is 1 mm to 3 mm. Normally, when filtering impurities in a sample using a filter nozzle, applying too much force presses the impurities against the filter surface, causing clogging and making it difficult for the sample to pass through. However, if the porous body has an appropriate pore size of 50 μm to 500 μm, a thickness of 0.5 mm to 3 mm, and a wide immersion volume, the sample absorbed by capillary action is filtered slowly and efficiently, similar to natural filtration, and is rapidly infused toward the top of the strip-shaped developing medium.

The invention described in claim 3 is the solvent-containing substance testing kit described in claim 1 or claim 2, in which a solvent container rib is provided at the opening of the solvent container and a coating container rib is provided on the covering container, and when the coating container is fitted to the solvent container, the solvent container rib and the coating container rib come into close contact with each other.

According to the invention described in claim 3, the solvent container and the covering container are each provided with ribs. By adopting a configuration in which these ribs come into close contact when the covering container is fitted onto the solvent container, it is possible to prevent the developing solvent from leaking (flowing out) to the outside. This can reduce safety risks due to leakage to the outside, particularly when samples contain substances containing cancer cells or non-enveloped viruses such as adenovirus, norovirus, and parvovirus, which are difficult to inactivate with surfactant treatment alone.

According to the invention described in claim 1, after inserting the cassette device into the solvent container, the covering container is fitted to the solvent container so as to seal the opening, thereby covering the cassette device. This eliminates the risk of the developing solvent leaking and target substances (such as infectious substances) scattering around and contaminating the surrounding environment, even if the solvent container is accidentally knocked over. Furthermore, there is no risk of dust, bacteria, viruses, or other airborne particles entering the solvent container through the opening during testing and adversely affecting the test results.

In particular, according to the invention described in claim 2, a porous body with a thickness of 0.5 mm to 3 mm is used as a constituent of the solvent immersion zone of the strip-shaped developing medium. Therefore, with the appropriate voids, appropriate thickness, and large immersion volume, the sample absorbed by capillary action is filtered slowly and efficiently in a manner similar to natural filtration. Therefore, even if the sample is highly viscous and contains impurities, the impurities are unlikely to interfere with the infusion of the developing solvent from the solvent immersion zone when the solvent immersion zone is immersed in the developing solvent.

Furthermore, according to the invention described in claim 3, the solvent container and the covering container are each provided with ribs. By adopting a configuration in which these ribs come into close contact when the covering container is fitted to the solvent container, it is possible to prevent the developing solvent from leaking (flowing out) to the outside. This can reduce safety risks due to leakage to the outside, particularly when specimens that are difficult to inactivate, such as substances containing cancer cells or viruses without an envelope, are included.

1 is a plan view showing a cassette-type device used in a solvent-containing substance test kit according to a first embodiment of the present invention. FIG. 1 is a perspective view showing the relationship between a squeeze bottle (solvent container) and a covering container that constitute a part of a solvent-containing substance testing kit according to a first embodiment of the present invention. FIG. 1 is a front view including a partial cross-sectional view showing a test being performed using a solvent-containing substance test kit according to a first embodiment of the present invention.

The following describes specific examples of the present invention. Here, we use as an example a solvent-containing substance test kit for testing influenza virus antigens.

As shown in Figures 1 to 3, the solvent-containing substance testing kit 10 according to Example 1 of the present invention includes a squeeze bottle (solvent container, hereinafter referred to as "bottle") 11A having an opening 11Aa on its top surface and containing a specimen containing target substance a to be detected and a specimen extract (developing solvent) at its bottom; a vertical cassette device 12 that is attached to bottle 11A and used to test for target substance a contained in the specimen; and a covering container 11B that is inserted into opening 11Aa of bottle 11A to fit onto bottle 11A and cover cassette device 12.

These components are described below.
The sample may be a nasal swab sample, a nasopharyngeal swab sample, a nasal mucus/nasal blow sample, a nasal aspirate sample, a pharyngeal swab sample, or the like, containing the target substance to be detected (e.g., influenza A virus).
The bottle 11A is a small test-tube-shaped container made of synthetic resin with a flange 11Ab formed at the top opening. The bottle 11A maintains an exposed specimen immersion zone (solvent immersion zone) 13A of the strip-shaped developing medium 13 (described later), and the inner wall of the bottle 11A holds the cassette device 12.
The covering container 11B is a container made of synthetic resin that can be fitted to the bottle 11A by being inserted into the opening 11Aa of the bottle 11A. The outer edge (outer wall) of the covering container 11B is rectangular, but the opening 11Ba is circular. Therefore, the covering container 11B can be fitted to the bottle 11A by inserting the covering container 11B into the opening of the bottle 11A. A flange 11Bb is provided on the covering container 11B at a position that contacts the flange 11Ab when the covering container 11B is fitted to the bottle 11A.

The cassette device 12 has a strip-shaped developing medium 13 into which a specimen extract can be infused by capillary action, and a vertically long medium storage case 14 in which the strip-shaped developing medium 13 can be stored.
The strip-shaped developing medium 13 is a stick-shaped immunochromatography medium made up of a plurality of members.
The strip-shaped developing medium 13 is arranged, from one end to the other in the longitudinal direction, with a specimen immersion zone 13A that is immersed in a specimen containing influenza virus, which is the target substance a to be detected; a labeled reagent zone 13B that contains a labeled reagent (conjugated antibody: gold colloid-labeled anti-influenza virus antibody) b that captures the target substance a; and a detection zone 13C that contains a capture substance (anti-influenza virus solid-phase antibody) c that captures the target substance a contained in the specimen A.

The medium storage case 14 is a vertically long container made of synthetic resin.
This medium storage case 14 is made up of a specimen immersion zone holding section 14A that holds the specimen immersion zone 13A portion of the strip-shaped developing medium 13 in an exposed state, a labeled reagent zone covering section 14B that covers the labeled reagent zone 13B portion of the strip-shaped developing medium 13, and a determination cassette section 14D that has a determination window 15 that exposes the detection zone 13C of the strip-shaped developing medium 13 and stores the upper part of the strip-shaped developing medium 13, all connected in an upward direction.

Of these, the specimen immersion zone holding section 14A is a shallow, elongated rectangular or semicircular gutter member that exposes the surface of the specimen immersion zone 13A. The specimen immersion zone holding section 14A may be a plate-like member that is shorter than the specimen immersion zone 13A, or may be omitted.
The labeled reagent zone covering portion 14B is a vertically long rectangular or semicircular container with an upper portion that is integrally connected to the upper end of the specimen immersion zone holding portion 14A and covers the entire area of the labeled reagent zone 13B.

A vertically long, rectangular test window 15 is formed on the front side of the lower part of the test cassette section 14D. On one side of the test window 15, the symbols A, B, and C are arranged from bottom to top to indicate the positions of the three test lines: top, middle, and bottom. Color development at position A indicates a positive reaction for influenza A; color development at position B indicates a positive reaction for influenza B; and color development at position C indicates a normal reaction. A small, horizontal window 14b is also formed directly above the test window 15. This small window 14b is a backflow prevention evaporation port that prevents the infusion of sample A that has reached the top end of the strip-shaped development medium 13 from flowing back into the test window 15.

The cassette device 12 is assumed to be fully assembled at the time of shipment from the factory, with the strip-shaped developing medium 13 attached to the medium storage case 14. Specifically, with the specimen immersion zone 13A exposed, the specimen immersion zone 13A is held by the specimen immersion zone holder 14A, the labeled reagent zone 13B is covered by the labeled reagent zone cover 14B, the detection zone 13C is exposed through the judgment window 15, and the upper part of the strip-shaped developing medium 13 is stored in the judgment cassette unit 14D.

Next, a sample testing method using a solvent-containing substance testing kit 10 according to a first embodiment of the present invention will be described with reference to FIGS.
When testing a sample, first, a cotton swab (not shown) containing a sample containing biological components is inserted into a test tube-shaped bottle 11A made of soft synthetic resin containing a sample extract (developing solvent), and then the sample is extracted into the sample extract by squeezing it with fingers from the outside of the bottle 11A.
Thereafter, the specimen immersion zone holding portion 14A and the labeled reagent zone covering portion 14B of the medium storage case 14 are inserted into the bottle 11A through the opening 11Aa, and the covering container 11B is inserted through the opening 11Aa of the bottle 11A, thereby fitting the covering container 11B to the bottle 11A. This causes the cassette device 12 to be attached to the bottle 11A in an upright position.

At this time, the exposed specimen immersion zone 13A of the strip-shaped developing medium 13 is immersed in a mixture of the specimen and specimen extract (hereinafter referred to as the specimen). As a result, the specimen absorbed in the specimen immersion zone 13A is infused toward the upper end of the strip-shaped developing medium 13. Along the way, in the labeled reagent zone 13B, the target substance a in the specimen binds with the labeled substance to form a complex. Whether or not the complex in the specimen is captured by the capture substance in the detection zone 13C is determined by observing the presence or absence of color development of the labeled substance through the determination window 15.

In this way, the bottle 11A and the covering container 11B form an airtight space, and the cassette device 12 is positioned so that it is covered within that airtight space. Therefore, even if the bottle 11A is accidentally knocked over during testing, there is no risk of the sample leaking and the target substance (infectious substance, etc.) a scattering around and contaminating the surrounding environment. Furthermore, there is no risk of dust, bacteria, viruses, or other suspended matter entering the bottle 11A through the opening 11Aa during testing and adversely affecting the test results. After the sample has been absorbed and developed, it can also be placed horizontally if this makes it easier to interpret.

In addition, the solvent container is a test-tube-shaped bottle 11A made of synthetic resin, making the solvent container inexpensive and easy to handle.

The solvent-containing substance testing kit of this invention is useful as a technology that allows for easy testing of target substances such as biological components and drugs contained in developing solvents.

10 Solvent-containing substance test kit,
11A solvent container,
11Aa opening,
11B coated container,
12 cassette devices,
13. Strip-shaped developing medium;
13A specimen immersion zone (solvent immersion zone),
13B labeled reagent zone,
13C detection zone,
14 media storage case,
14A specimen immersion zone holder (solvent immersion zone holder),
14B labeled reagent zone covering portion;
14D judgment cassette part,
15 judgment window,
a Target substance.

Claims (3)

a solvent container having an opening and containing a developing solvent containing a target substance to be detected at the bottom;
a vertical cassette device that is attached to the solvent container through an opening thereof and that inspects the target substance contained in the developing solvent;
a covering container that fits over the solvent container to seal the opening, and that covers and seals the cassette device;
the cassette device includes a longitudinally long strip-shaped developing medium into which the developing solvent can be infused by capillary action, and a longitudinally long medium storage case capable of storing the strip-shaped developing medium;
the strip-shaped developing medium has a solvent immersion zone immersed in the developing solvent, a labeled reagent zone containing a labeled reagent for labeling the target substance, and a detection zone containing a capture substance for capturing the target substance, which are arranged in this order from the bottom end to the top end of the strip-shaped developing medium;
the medium storage case is arranged in an upward direction in this order: a solvent immersion zone holding section that holds the solvent immersion zone of the strip-shaped developing medium in an exposed state; a labeled reagent zone covering section that covers the labeled reagent zone of the strip-shaped developing medium; and a determination cassette section that has a determination window that exposes the detection zone of the strip-shaped developing medium and that stores an upper portion of the strip-shaped developing medium;
After the cassette device is inserted into the solvent container, the cassette device is fitted onto the solvent container to seal the opening, thereby covering the cassette device. The solvent-containing substance test kit described in claim 1, characterized in that the solvent immersion zone of the strip-shaped development medium is made of a porous material having a thickness of 0.5 mm to 3 mm. a solvent container rib is provided at the opening of the solvent container;
The coated container is provided with a coated container rib,
3. A solvent-containing substance testing kit as described in claim 1 or claim 2, wherein when the covering container is fitted to the solvent container, the solvent container rib and the covering container rib come into close contact with each other, thereby covering and sealing the cassette device.