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EP-4741825-A1 - TEST KIT

EP4741825A1EP 4741825 A1EP4741825 A1EP 4741825A1EP-4741825-A1

Abstract

[Problem] To provide a test kit that does not require a complicated device to perform detection and that allows easier detection confirmation than conventional test kits in which chromatography is used. [Solution] Provided is a test kit including: a sample pad that absorbs a sample; a conjugate pad that has a detection marker supported thereon; a chromatographic body that has a membrane; an absorption pad that prevents backflow of the sample; and a light source that irradiates light of 300 nm to 400 nm. The test kit is characterized in that the detection marker is a fluorescent substance that emits light having a wavelength of at least 600 nm when light having a wavelength of 300 nm to 400 nm is applied.

Inventors

  • SHIBASAKI FUTOSHI
  • KAJIWARA NAOKI

Assignees

  • Lifetrek Inc.

Dates

Publication Date
20260513
Application Date
20240703

Claims (6)

  1. A test kit comprising: a sample pad configured to absorb a specimen; a conjugate pad supporting a detection marker; a chromatographic body comprising a membrane; an absorption pad configured to prevent backflow of the specimen; and a light source configured to emit light of 300 nm to 400 nm, wherein the detection marker contains a fluorescent substance that emits light having a wavelength of 600 nm or more when irradiated with light having a wavelength of 300 nm to 400 nm.
  2. The test kit according to claim 1, wherein the fluorescent substance is a rare earth complex.
  3. The test kit according to claim 1, wherein the fluorescent substance has a fluorescence brightness of 0.8 or more when a brightness of an excitation light is set to 1.
  4. The test kit according to claim 1, further comprising: a fluorescent color level sample, wherein the test kit is configured to allow quantification by visually comparing a color level of the fluorescent color level sample with a chromatographic fluorescent color on the chromatographic body.
  5. The test kit according to claim 2, wherein the fluorescent substance is a polymer particle encapsulating t the rare earth complex.
  6. The test kit according to claim 5, wherein a mixing ratio of the detection antibody to the polymer particle, which is the antibody/the particle (mg/g), in the detection marker is 20 to 80.

Description

Technical Field The present invention relates to a test kit for detecting various target objects such as an antibody, an antigen, a protein, a biomarker, a chemical molecule, and a nucleic acid. More specifically, the present invention relates to a test kit that does not require a complicated device for detection and allows for easier detection and confirmation compared to conventional chromatography-based test kits. Background Art A large number of test kits for detecting various target objects, such as an antibody, an antigen, a protein, a biomarker, a chemical molecule, and a nucleic acid, have been proposed. Among these, test kits using immunochromatography are widely used due to the ease of use thereof, and various types thereof have been proposed. For example, PTL 1 proposes an immunochromatography test piece that is capable of achieving both highly sensitive detection of a substance to be detected and a simple test piece structure, which are generally mutually exclusive. Specifically, an immunochromatographic test piece has been proposed, wherein the immunochromatographic test piece is an immunochromatographic test piece for measuring a substance to be detected, by: including therein a membrane on which a capture substance is immobilized, which is a ligand that binds to a substance to be detected; using insoluble carrier particles to which a ligand that binds to a substance to be detected is bound; accumulating the insoluble carrier particles by capturing the same with the capture substance immobilized on the membrane; and irradiating the membrane with light to detect light emitted at a site where the insoluble carrier particles have accumulated or at a surrounding site other than the site where the insoluble carrier particles have accumulated, and wherein the immunochromatographic test piece includes a light-reflecting material on a side opposite to the side, where the light is applied, of the membrane. In addition, PTL 2 proposes a test kit that has excellent detection sensitivity for a substance to be detected. Specifically, a test kit has been proposed, wherein the test kit has: on a base material, a reagent retaining portion containing a labeling reagent in which a binding substance that specifically binds to a substance to be detected is immobilized on labeled fine particles; and a test part on which a test capture substance that specifically binds to a substance to be detected is immobilized, and the labeled fine particles are fine particles made of a noble metal, and the test part contains an up-conversion material. In addition, PTL 3 discloses a test kit, wherein the test kit is a test kit for detecting and/or quantifying a biological or chemical substance of interest in a liquid sample with a capillary action test by using, as a probe, photoluminescent inorganic nanoparticles of Formula A1 - xLnxVO4 (1-y) (PO4)y (II), where in the formula, Ln is selected from europium (Eu), dysprosium (Dy), samarium (Sm), neodymium (Nd), erbium (Er), ytterbium (Yb), thulium (Tm), praseodymium (Pr), holmium (Ho), and a mixture thereof, A is selected from yttrium (Y), gadolinium (Gd), lanthanum (La), lutetium (Lu), and a mixture thereof, 0 < x < 1 and 0 ≤ y <1 are satisfied, and moreover the method thereof detects emission of nanoparticles having an emission lifetime of less than 100 ms after one-photon absorption by exciting a matrix at a wavelength of 320 nm or less. Citation List Patent Literature PTL 1: JP No. 2015-31610APTL 2: JP No. 2017-223616APTL 3: JP No. 2021-530700A Summary of Invention Technical Problem However, in the test kit proposed above, the chromatographic results cannot be clearly confirmed by visual inspection(observation), and thus it is necessary to use a detection device for reading. This poses a problem in that detection and confirmation cannot be easily carried out due to , for instance, the requirement for a complicated device. As a result, an object of the present invention is to provide a test kit that does not require a complicated device for detection and allows detection and confirmation to be implemented easier, as compared with conventional chromatography-based test kits. Solution to Problem As a result of carrying out intensive studies to solve the above-described problems, the inventors have found that when a europium complex is used for a target reagent, detection and confirmation can be carried out by visual inspection(observation) using only ultraviolet light (such as a commonly used so-called "black light") without a special device. and as a result of carrying out further studies based on such finding, the inventors of the present invention have completed the present invention. That is, the present invention provides each of the following inventions. 1. A test kit comprising: a sample pad that absorbs a specimen;a conjugate pad on which a detection marker is supported;a chromatographic body comprising a membrane;an absorption pad that prevent backflow of the specimen; a