JP2009063482A - Absorbing member and kit for immuno-chromatography - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an absorbing member capable of eliminating the ambiguity of determination by smearing of a determination section by sharply reducing liquid return of sample liquid in a kit for immuno-chromatography, and to provide a kit for immuno-chromatography including the absorbing member. <P>SOLUTION: The absorbing member is used as a component member of the kit for immuno-chromatography, and contains high absorbent fiber of water swelling degree of 10 times or more. The kit for immuno-chromatography contains the absorbing member. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an absorbent member used as a constituent member of an immunochromatography kit and an immunochromatography kit including the absorbent member.

  There is a method of using immunochromatography as a method for easily examining various diseases using a body fluid such as blood, serum, or pharyngeal wipe as a specimen (see, for example, Patent Documents 1, 2, and 3).

  A kit for testing using such immunochromatography includes a sample adding part, a labeling part containing a labeled substance labeled with a capture substance (antibody or antigen) corresponding to an antigen or antibody as a test substance in the sample, A porous carrier on which a capture substance (antibody or antigen) corresponding to an antigen or antibody as a test substance is immobilized (having a function as a development part and a judgment part), and an absorbing member that absorbs an excess sample Composed.

  In the immunochromatography kit, when a liquid containing a sample is added to the sample addition part, the test substance moves by capillary action in the order of the label part, the porous carrier, and the absorbent member using the liquid as a moving layer. At this time, when the sample solution is added to the sample addition portion, the labeled substance labeled with the latex particles that have been dried forms a complex with the test substance in the sample solution while moving by the sample solution. This complex moves on the porous carrier, and is captured by the trapping substance fixed to the porous carrier, so that a colored line of latex particles is formed in the determination part. By visually observing this colored line, the presence or absence of the measurement target in the sample liquid can be confirmed. Examples of the detection substance include bacteria that cause an antigen-antibody reaction, cells such as protists and fungi, viruses, proteins, and polysaccharides.

However, in the conventional immunochromatography kit, since the water absorption of the absorbent member made of a cotton non-woven sheet or the like is not sufficient, the sample liquid once absorbed returns to the determination unit, and the line formed in the determination unit is blurred. There was a problem that the judgment became ambiguous.
Note that a highly water-absorbing fiber having a high degree of water swelling is conventionally known, for example, from Patent Document 4.

JP 2001-289852 A JP 2006-194687 A JP 2006-194688 A Japanese Patent Laying-Open No. 2005-200785

  The present invention has been made in view of the above background, and in an immunochromatography kit, an absorbent member capable of eliminating the ambiguity of determination due to bleeding of the determination unit by greatly reducing the liquid return of the sample liquid And an immunochromatography kit including the absorbent member.

  As a result of intensive studies to achieve the above-mentioned problems, the present inventor has found that a desired absorbent member can be obtained by configuring an absorbent member using superabsorbent fibers, and has further intensively studied the present invention. It came to be completed.

  Thus, according to the present invention, “an absorbent member used as a component of an immunochromatography kit, wherein the absorbent member includes a superabsorbent fiber having a water swelling degree of 10 times or more. Is provided.

  In that case, it is preferable that the superabsorbent fiber is any one selected from the group consisting of a crosslinked sodium polyacrylate fiber, an acrylate fiber obtained by hydrolyzing the surface of the acrylic fiber, and a PVA fiber. Moreover, it is preferable that the single fiber fineness of the said superabsorbent fiber exists in the range of 1-20 dtex.

  In the absorbent member of the present invention, the superabsorbent fiber is preferably contained in an amount of 5 to 80% by weight based on the total weight of the absorbent member. Moreover, it is preferable that 10-80 weight% of heat-fusible fiber is contained as another fiber with respect to the total weight of an absorption member. In that case, it is preferable that the said heat-fusible fiber is a heat-fusible fiber containing the heat-fusible component which consists of polyethylene.

In the absorbent material of the present invention, the absorbent member preferably has a sheet-like shape. Moreover, it is preferable that an absorption member is the air laid nonwoven fabric manufactured by the air laid method. Moreover, it is preferable that an absorption member has a 3 layer structure which consists of a surface layer, an intermediate | middle layer, and a back layer, and the said absorptive fiber is contained only in an intermediate | middle layer. In that case, it is preferable that a hydrophilic fiber is contained in the surface layer and the back layer. The thickness of the absorbing member is preferably in the range of 0.3 to 2 mm. The basis weight is preferably in the range of 50 to 1000 gr / m ² . In the absorbent member, the water absorption measured by the following is preferably 200% by weight or more.

First, the sample (width 2.5 cm × length 18 cm) is conditioned by placing it in an atmosphere at a temperature of 20 ° C. and a relative humidity of 65% for 12 hours, and then the weight W1 of the sample is measured. Next, in an atmosphere at a temperature of 20 ° C. and a relative humidity of 65%, with the sample suspended vertically, a portion from the lower end of the sample to 0.5 cm is immersed in the water surface to absorb water, and after 10 minutes, Is removed, and the weight W2 after water absorption is measured. And a water absorption is computed by a following formula.
Water absorption (%) = (W2−W1) / W1 × 100

  Moreover, according to this invention, the kit for immunochromatography containing the said absorption member is provided.

  According to the present invention, in an immunochromatography kit, an absorption member capable of eliminating the ambiguity of determination due to bleeding of the determination unit by greatly reducing the return of the sample solution, and an immunochromatography including the absorption member A graphy kit is obtained.

Hereinafter, embodiments of the present invention will be described in detail.
The absorbing member of the present invention is an absorbing member used as a constituent member of an immunochromatography kit, and absorbs an excessive sample solution.

The absorbent member of the present invention includes superabsorbent fibers having a water swelling degree of 10 times or more (preferably 30 to 300 times). Here, the degree of water swelling is measured by the following method. First, 0.4 g of superabsorbent fiber is immersed in 300 cc of physiological saline, left for 30 minutes, then poured onto a 32 mesh metal sieve and drained for 10 minutes. And the mass (gr) of the gel-like fiber which remained on the mesh is measured, and a water swelling degree is computed by a following formula.
Water swell degree = (gel fiber mass [gr] −0.4 [gr]) / 0.4 [gr]

  Examples of such superabsorbent fibers include cross-linked poly (sodium acrylate) fibers (for example, “BEL OASIS” (registered trademark) manufactured by Teijin Fibers Ltd.), acrylate fibers obtained by hydrolyzing the surface of acrylic fibers, PVA fibers, and the like. The These superabsorbent fibers may be used alone or in combination of two or more.

  The single fiber fineness of the superabsorbent fiber is preferably in the range of 1 to 20 dtex. If the single fiber fineness is less than 1 dtex, it may be difficult to produce superabsorbent fibers. On the other hand, if the single fiber fineness is larger than 20 dtex, sufficient water absorption performance may not be obtained.

  In the absorbent member of the present invention, the mixing ratio of the superabsorbent fibers is not limited and can be arbitrarily selected according to the water absorption performance and fiber strength of the fibers used, but the mixing ratio (weight ratio) of the superabsorbent fibers is absorbed. It is preferable to be within the range of 5 to 80% by weight (more preferably 20 to 50% by weight) with respect to the total weight of the member. When the mixing ratio is less than 5% by weight, sufficient water absorption performance may not be obtained. On the other hand, when the mixing ratio is larger than 80% by weight, the handleability may be impaired.

  In the absorbent member of the present invention, when other fibers other than the superabsorbent fibers are included, the other fibers include synthetic fibers such as polyester fibers, nylon fibers and polyolefin fibers, natural fibers such as cotton, and regenerated fibers such as rayon. Examples thereof include fibers. Especially, it is preferable that 10-80 weight% (more preferably 20-50 weight%) of heat-fusible fiber is contained. When the heat-fusible fiber is contained in the absorbent member, swelling in the thickness direction during water absorption can be suppressed, and as a result, sufficient water absorption performance is exhibited. Here, when the content of the heat-fusible fiber is less than 10% by weight, the absorbent member easily swells in the thickness direction upon water absorption. Therefore, in a state where the absorbent member is stored in an immunochromatography kit with a limited volume. There is a possibility that sufficient water absorption performance is not exhibited. On the contrary, when the content of the heat-fusible fiber is larger than 80% by weight, the content of the highly water-absorbent fiber is small, so that sufficient water absorption performance may not be exhibited.

  The heat-fusible fiber referred to in the present invention is a fiber containing a heat-fusible component that melts at 160 ° C. or less (preferably 90 to 120 ° C.). A composite fiber composed of a non-fusing component having a melting point higher than that of the adhering component is preferable.

  In addition, as the heat-fusible fiber, a core-sheath type composite fiber in which the sheath component is made of polyethylene, isophthalic acid, caprolactone copolymer polyester or polyether ester, and the core component is made of polypropylene or polyethylene terephthalate is preferable. Moreover, the composite fiber by which the sheath component and the core component were joined by the side-by-side type may be sufficient.

  In the absorbent member of the present invention, the shape is preferably a sheet from the viewpoint of handleability. Moreover, the structure is not specifically limited, Any of a woven fabric, a knitted fabric, and a nonwoven fabric may be sufficient. Among these, non-woven fabrics are preferable because the interstitial voids are small and excellent water absorption performance is obtained. Examples of the nonwoven fabric include nonwoven fabrics manufactured by an airlaid method, a needle punch method, a thermal bond method, a chemical bond method, and the like. Of these, nonwoven fabrics obtained by the airlaid method are preferred. Nonwoven fabrics produced by the airlaid method are preferred because highly water-absorbing fibers are easily arranged uniformly in the structure, and even when the use area is small as in this application, variations in water absorption performance are reduced.

  Further, the member of the present invention may have a single-layer structure consisting of only a layer containing a superabsorbent fiber, but a layer not containing a superabsorbent fiber is disposed above and below a layer containing a superabsorbent fiber. It preferably has a three-layer structure. If the single-layer structure is composed only of layers containing superabsorbent fibers, the surface of the absorbent member may become sticky due to the superabsorbent fibers that have gelled during water absorption, and the handling properties may be impaired.

  In that case, it is preferable that the layer which does not contain a superabsorbent fiber is comprised with a hydrophilic fiber. When a layer composed of hydrophilic fibers is arranged above and below a layer containing superabsorbent fibers to form a three-layer structure, the absorption rate of the sample solution is higher than that of a single-layer structure consisting only of layers containing superabsorbent fibers. It is possible to increase. At this time, the hydrophilic fiber is preferably cotton fiber or rayon fiber.

  As the absorbent member of the present invention, the nonwoven fabric obtained by the above-mentioned production method or the woven or knitted fabric knitted and woven by a conventional method may be used as it is. preferable. By hot pressing, the water absorption performance can be increased by increasing the density, and when the water-absorbing fiber is contained in the water-absorbing member, the heat-fusible fiber can be heat-sealed. In addition, if the purpose of the present invention is within the range not impairing, antibacterial processing, dyeing processing, hydrophilic processing, etc., in which an antibacterial agent or a fungicide is added before and / or after the production of the member is performed. You may give it.

  In the absorbent member thus obtained, the thickness is preferably in the range of 0.3 to 2 mm (more preferably 0.5 to 1.5 mm). If the thickness is less than 0.3 mm, the water absorption performance may be impaired. Conversely, if the thickness is greater than 2 mm, the handleability may be impaired.

Further, it is preferable that as the basis weight 50~1000gr / ^{m 2} (more preferably 70~300gr / ^{m 2)} is in the range of. If the basis weight is less than 50 gr / m ² , water absorption performance may be impaired. On the other hand, when the basis weight is larger than 1000 gr / m ^{2, the} handleability may be impaired.

  Since the absorbent member of the present invention contains the high-absorbency fiber as described above, it exhibits excellent water absorption performance and greatly reduces the liquid return of the sample solution, thereby making the determination part ambiguity due to line blurring. Can be solved. As such absorption performance, it is preferable that the water absorption measured by the following is 200% by weight or more (more preferably 300 to 1000% by weight).

First, a sample (width 2.5 cm × length 18 cm) is conditioned by placing it in an atmosphere at a temperature of 20 ° C. and a relative humidity of 65% for 12 hours, and then the weight W1 (gr) of the sample is measured. Next, in an atmosphere at a temperature of 20 ° C. and a relative humidity of 65%, with the sample suspended vertically, a portion from the lower end of the sample to 0.5 cm is immersed in the water surface to absorb water, and after 10 minutes, Is removed and the weight W2 (gr) after water absorption is measured. And a water absorption is computed by a following formula.
Water absorption (%) = (W2−W1) / W1 × 100

  Next, the immunochromatography kit of the present invention is an immunochromatography kit including the above-described absorbing member as a constituent member. Since such a kit includes the above-described absorbing member, it is possible to resolve the ambiguity of determination due to blurring of the line of the determination unit by greatly reducing the return of the sample liquid.

  Next, although the Example and comparative example of this invention are explained in full detail, this invention is not limited by these. In addition, each measurement item in an Example was measured with the following method.

(1) Water swelling degree It measured with the following method. First, 0.4 g of superabsorbent fiber was immersed in 300 cc of physiological saline, allowed to stand for 30 minutes, then poured onto a 32 mesh metal sieve and drained for 10 minutes. And the mass (gr) of the gel-like fiber which remained on the mesh was measured, and the water swelling degree was computed by the following formula.
Water swell degree = (gel fiber mass [gr] −0.4 [gr]) / 0.4 [gr]

(2) Water Absorption Rate of Absorbing Member After conditioning the sample (width 2.5 cm × length 18 cm) by placing it in an atmosphere at a temperature of 20 ° C. and a relative humidity of 65% for 12 hours, the weight W1 (gr of the sample ) Was measured. Next, in an atmosphere at a temperature of 20 ° C. and a relative humidity of 65%, with the sample suspended vertically, a portion from the lower end of the sample to 0.5 cm is immersed in the water surface to absorb water, and after 10 minutes, The weight W2 (gr) after water absorption was measured. And the water absorption was computed by the following formula.
Water absorption (%) = (W2−W1) / W1 × 100

(3) Thickness of absorbent member Measured according to JIS L1085.

(4) Line bleeding of determination unit The sample liquid was conducted to the immunochromatography kit, and after 15 minutes, the line bleeding indicating the conduction of the sample liquid was confirmed. The degree of bleeding of the line was evaluated based on the following evaluation criteria.
Grade 4: No blur is observed and the line is clear.
Grade 3: Some line bleeding is observed.
Second grade: Line bleeding is observed, but barely possible.
First grade: Bleeding is severe and cannot be determined.

(5) Melting point Using a differential thermal analyzer 990 manufactured by Du Pont, measured at a temperature increase of 20 ° C./min, and obtained a melting peak. When the melting temperature was not clearly observed, the melting point was defined as the temperature at which the polymer softened and started to flow (softening point) using a micro melting point measuring device (manufactured by Yanagimoto Seisakusho). In addition, the average value was calculated | required by n number 5.

[Example 1]
Super water-absorbing fiber "BEL OASIS" (registered trademark) (single fiber fineness 10 dtex, fiber length 5 mm) 30% by weight manufactured by Teijin Fibers Ltd., which has a water swelling degree 45 times, and polyolefin thermal fusion fiber "manufactured by Chisso Corporation" Intac "(trade name) (single fiber fineness 2.2 dtex, fiber length 5 mm, sheath component: polyethylene with melting point 130 ° C., core component: polypropylene with melting point 160 ° C., water swelling degree less than 10 times) 70% by weight An absorbent member (thickness: 1.0 mm) of the present invention was obtained by producing a non-woven fabric of 216 g / m ^{2 by} an airlaid method and hot pressing at a temperature of 130 ° C. Moreover, using the absorbent member, an immunochromatography kit as schematically shown in FIG. 1 was prepared. Table 1 shows the evaluation results of the absorbent member and the immunochromatography kit.

[Example 2]
101 g of basis weight comprising 30% by weight of the same superabsorbent fiber as in Example 1, 30% by weight of Example 1 and heat-fusible fiber, and 40% by weight of bleached pulp pulverized by a hammer mill (water swelling degree is less than 10 times). An absorbent member (thickness: 1.1 mm) was obtained by producing a nonwoven fabric of / m ² by the airlaid method and hot pressing at a temperature of 130 ° C. Moreover, using the absorbent member, an immunochromatography kit as schematically shown in FIG. 1 was prepared. Table 1 shows the evaluation results of the absorbent member and the immunochromatography kit.

[Example 3]
A nonwoven fabric having a structure in which a cotton spunlace nonwoven fabric “Cot Ace” (trade name) (mesh weight 40 g / m ² ) manufactured by Unitika Ltd. was pasted on the upper and lower sides of the absorbent pad obtained in Example 2 (mesh weight 187 g / m ² ). The absorbent member (thickness 1.1 mm) was obtained by producing and further hot pressing. Moreover, using the absorbent member, an immunochromatography kit as schematically shown in FIG. 1 was prepared. Table 1 shows the evaluation results of the absorbent member and the immunochromatography kit.

[Comparative Example 1]
The cotton fibers were subjected to ordinary treatment by carding, cross laying, and needle punching to produce a nonwoven fabric having a basis weight of 310 g / m ² and a thickness of 1.5 mm. Further, an absorbing member (thickness: 0.9 mm) was obtained by hot pressing. Moreover, using the absorbent member, an immunochromatography kit as schematically shown in FIG. 1 was prepared. Table 1 shows the evaluation results of the absorbent member and the immunochromatography kit.

  According to the present invention, in an immunochromatography kit, an absorption member capable of eliminating the ambiguity of determination due to bleeding of the determination unit by greatly reducing the return of the sample solution, and an immunochromatography including the absorption member A graphic kit is obtained, and its industrial value is enormous.

It is (a) top view and (b) side view of the kit for immunochromatography.

Explanation of symbols

1: Sample addition part 2: Labeling part 3: Porous carrier 4: Absorbing member 5: Substrate

Claims (14)

  An absorbent member used as a constituent member of an immunochromatography kit, wherein the absorbent member includes superabsorbent fibers having a water swelling degree of 10 times or more.   The absorption according to claim 1, wherein the superabsorbent fiber is any one selected from the group consisting of a crosslinked poly (sodium acrylate) fiber, an acrylate fiber obtained by hydrolyzing the surface of an acrylic fiber, and a PVA fiber. Element.   The absorbent member according to claim 1 or 2, wherein a single fiber fineness of the superabsorbent fiber is in a range of 1 to 20 dtex.   The absorbent member according to claim 1, wherein the superabsorbent fiber is contained in an amount of 5 to 80% by weight based on the total weight of the absorbent member.   The absorbent member according to any one of claims 1 to 4, further comprising 10 to 80% by weight of heat-fusible fiber with respect to the total weight of the absorbent member.   The absorbent member according to claim 5, wherein the heat-fusible fiber is a heat-fusible fiber containing a heat-fusible component made of polyethylene.   The absorbent member according to claim 1, wherein the absorbent member has a sheet-like shape.   The absorbent member according to any one of claims 1 to 7, wherein the absorbent member is an airlaid nonwoven fabric produced by an airlaid method.   The absorbent member according to any one of claims 1 to 8, wherein the absorbent member has a three-layer structure including a surface layer, an intermediate layer, and a back layer, and the absorbent fiber is contained only in the intermediate layer.   The absorbent member according to claim 9, wherein hydrophilic fibers are contained in the surface layer and the back layer.   The absorbent member according to any one of claims 7 to 10, wherein the thickness is within a range of 0.3 to 2 mm. Basis weight in the range of 50~1000gr / ^{m 2,} the absorption member according to any one of claims 7-11. The absorption member in any one of Claims 1-12 whose water absorption rate measured by the following is 200 weight% or more in an absorption member.
First, the sample (width 2.5 cm × length 18 cm) is conditioned by placing it in an atmosphere at a temperature of 20 ° C. and a relative humidity of 65% for 12 hours, and then the weight W1 of the sample is measured. Next, in an atmosphere at a temperature of 20 ° C. and a relative humidity of 65%, with the sample suspended vertically, a portion from the lower end of the sample to 0.5 cm is immersed in the water surface to absorb water, and after 10 minutes, Is removed, and the weight W2 after water absorption is measured. And a water absorption is computed by a following formula.
Water absorption (%) = (W2−W1) / W1 × 100   An immunochromatography kit comprising the absorbent member according to claim 1.

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