Method of detecting target substance

Patent metadata

Field	Value
Publication number	US-2016291003-A1
Application number	US-201615088742-A
Country	US
Kind code	A1
Filing date	Apr 1, 2016
Priority date	Oct 2, 2013
Publication date	Oct 6, 2016
Grant date	—

Abstract

A method of detecting a target substance, containing the steps of:
incorporating labeling particles into a test liquid containing an analyte; heating the test liquid; irradiating the test liquid with excitation light, and detecting the target substance contained in the test liquid depending on a state of light emission of the labeling particles; wherein an aggregation state of the labeling particles is changed by the heating step; and wherein the labeling particles have a thermoresponsive polymer on a surface of a composite particle containing a magnetic material and a fluorescent material, and further have a biomolecule having properties of binding with the target substance.

First claim

1 . A method of detecting a target substance, comprising the steps of:
incorporating labeling particles into a test liquid comprising an analyte; heating the test liquid; irradiating the test liquid with excitation light, and detecting the target substance included in the test liquid depending on a state of light emission of the labeling particles;
wherein an aggregation state of the labeling particles is changed by the heating step; and
wherein the labeling particles have a thermoresponsive polymer on a surface of a composite particle comprising a magnetic material and a fluorescent material, and further have a biomolecule having properties of binding with the target substance.

2 . The method of detecting a target substance according to claim 1 ,
wherein non-existence of the target substance is identified by development of fluorescence emission of the labeling particles that are locally gathered in the test liquid after the heating step, and existence of the target substance is identified by no development of the fluorescence emission of the gathered labeling particles.

3 . The method of detecting a target substance according to claim 1 ,
wherein a dispersant is introduced into the test liquid.

4 . The method of detecting a target substance according to claim 1 ,
wherein a wavelength of the excitation light is 300 to 700 nm and a wavelength of the fluorescence is 350 to 800 nm.

5 . The method of detecting a target substance according to claim 1 ,
wherein the composite particle comprises a phase having the magnetic material and a phase having the fluorescent material, and wherein the phase having the fluorescent material is constituted of a continuous phase formed of a transparent material and a dispersed phase formed of the fluorescent material.

6 . The method of detecting a target substance according to claim 1 ,
wherein the test liquid is heated so as to span a critical solution temperature (CST) of the thermoresponsive polymer in the range of 10° C. to 100° C.

7 . The method of detecting a target substance according to claim 1 ,
wherein magnetic force is provided for the test liquid and the labeling particles in an aggregated state are gathered in a portion provided with the magnetic force.

8 . The method of detecting a target substance according to claim 1 ,
wherein an average particle diameter of the composite particle is less than 1 μm.

9 . The method of detecting a target substance according to claim 5 ,
wherein the transparent material comprises silica or polystyrene.

10 . The method of detecting a target substance according to claim 1 ,
wherein the magnetic material is magnetite, nickel oxide, ferrite, cobalt iron oxide, barium ferrite, carbon steel, tungsten steel, KS steel, a rare earth cobalt magnet or hematite.

Assignees

• Furukawa Electric Co Ltd

Inventors

• Fukushima Masayuki
• Ohkubo Michio
• Miyoshi Kazutomi
• Nishida Masataka

Classifications

• G01N21/6428 Primary

  Measuring fluorescence of fluorescent products of reactions or of fluorochrome labelled reactive substances, e.g. measuring quenching effects, using measuring "optrodes" (in vivo A61B5/00; immunoassay G01N33/53) · CPC title

• G01N2021/6439

  with indicators, stains, dyes, tags, labels, marks · CPC title

• G01N33/54346

  Nanoparticles · CPC title

• G01N33/54333 Primary

  Modification of conditions of immunological binding reaction, e.g. use of more than one type of particle, use of chemical agents to improve binding, choice of incubation time or application of magnetic field during binding reaction · CPC title

• G01N33/552

  Glass or silica · CPC title