Extraction method, analytical method, extraction device, and analytical device

Patent metadata

Field	Value
Publication number	US-2017191114-A1
Application number	US-201615363247-A
Country	US
Kind code	A1
Filing date	Nov 29, 2016
Priority date	May 29, 2015
Publication date	Jul 6, 2017
Grant date	—

Abstract

The present invention is a method for extracting nucleic acid. A biological sample existing in a fluid is trapped using metal mesh. The biological sample contains nucleic acid and a coating structure covering the nucleic acid. The metal mesh with the biological sample trapped thereon is immersed in a nucleic acid extractant. The nucleic acid extractant is a solvent for the nucleic acid but not for the coating structure.

First claim

1 . A method for extracting nucleic acid, the method comprising:
trapping a biological sample existing in a fluid using metal mesh, the biological sample containing nucleic acid and a coating structure covering the nucleic acid; immersing the metal mesh with the biological sample trapped thereon in a nucleic acid extractant which is a solvent for the nucleic acid but not for the coating structure; and thereafter collecting the nucleic acid extractant.

2 . The extraction method according to claim 1 , wherein the metal mesh has an aperture size which is smaller than the average size of the biological sample and larger than the average size of the nucleic acid.

3 . The extraction method according to claim 1 , wherein the metal mesh is insoluble in the nucleic acid extractant.

4 . The extraction method according to claim 1 , wherein the nucleic acid extractant contains phenol.

5 . The extraction method according to claim 4 , wherein the nucleic acid extractant also contains chloroform.

6 . The extraction method according to claim 1 , wherein trapping the biological sample includes removing a material other than the biological sample from the fluid using a pre-filter before trapping the biological sample on the metal mesh.

7 . A method for analyzing a biological sample, the method comprising extracting nucleic acid in accordance with claim 1 and thereafter analyzing nucleic acid.

8 . A method for extracting nucleic acid from first and second biological samples existing in a fluid, the first biological sample having a different average size than the second biological sample, the method comprising:
trapping the first and second biological samples using first and second metal meshes, respectively, the first biological sample containing a first nucleic acid and a first coating structure covering the first nucleic acid, the second biological sample containing a second nucleic acid and a second coating structure covering the second nucleic acid; immersing the first and second metal meshes, with the respective biological samples trapped thereon, in a nucleic acid extractant which is a solvent for both the first and second nucleic acids but is not a solvent for the first or second coating structures; and thereafter separately collecting the first and second nucleic acids.

9 . A method for extracting nucleic acid in accordance with claim 8 , wherein the first metal mesh has an aperture size smaller than the average size of the first biological sample and larger than the average size of the first nucleic acid and the second metal mesh has an aperture size smaller than the average size of the second biological sample and larger than the average size of the second nucleic acid.

10 . An extraction device comprising:
a trap having a channel for a fluid; metal mesh in the channel of the trap for trapping a biological sample existing in the fluid, the biological sample containing nucleic acid and a coating structure covering the nucleic acid; and a container that holds a nucleic acid extractant that is a solvent for the nucleic acid but is not a solvent for the coating structure such that the metal mesh, and with it the biological sample trapped on the metal mesh, can be immersed in the nucleic acid extractant.

11 . The extraction device according to claim 10 , wherein the metal mesh has an aperture size which is smaller than the average size of the biological sample and larger than the average size of the nucleic acid.

12 . The extraction device according to claim 8 , wherein the metal mesh is insoluble in the nucleic acid extractant.

13 . The extraction device according to claim 10 , wherein the nucleic acid extractant contains phenol.

14 . The extraction device according to claim 13 wherein the nucleic acid extractant also contains chloroform.

15 . The extraction device according to claim 10 , further comprising a pre-filter located upstream of the metal mesh in the channel in the trap for removing a material other than the biological sample from the fluid.

16 . The extraction device according to claim 10 , wherein the trap is a syringe barrel and
the extraction device further includes a gasket which is slidable in the syringe barrel to form a liquid tight seal and a plunger connected to the gasket.

17 . A device for analyzing a biological sample, the device comprising:
an extraction device according to claim 10 ; and an analyzer for analyzing nucleic acid extracted by the extraction device.

18 . An extraction device comprising:
a trap having a channel for a fluid; first and second metal meshes located in the channel for trapping first and second biological samples existing in the fluid, the first biological sample containing a first nucleic acid and a first coating structure covering the first nucleic acid, the second biological sample containing a second nucleic acid and a second coating structure covering the second nucleic acid; and a container that holds a nucleic acid extractant that is a solvent for both the first and the second nucleic acid but is not a solvent for either the first or the second coating structure such that the first metal mesh, and with it the first biological sample trapped on the first metal mesh, and the second metal mesh, and with it the second biological sample trapped on the second metal mesh, can be immersed in the nucleic acid extractant.

19 . The extraction device in accordance with claim 18 , wherein the first metal mesh has an aperture size smaller than the average size of the first biological sample and larger than the average size of the first nucleic acid and the second metal mesh has an aperture size smaller than the average size of the second biological sample and larger than the average size of the second nucleic acid.

Assignees

• Murata Manufacturing Co

Inventors

• Kamba Seiji
• Kondo Takashi
• Hasegawa Makoto

Classifications

• C12Q1/6806 Primary

  Preparing nucleic acids for analysis, e.g. for polymerase chain reaction [PCR] assay (C12Q1/6804 takes precedence) · CPC title

• G01N2001/1006

  Dispersed solids · CPC title

• C12Q1/24

  Methods of sampling, or inoculating or spreading a sample; Methods of physically isolating an intact microorganisms · CPC title

• C12Q1/04

  Determining presence or kind of microorganism; Use of selective media for testing antibiotics or bacteriocides; Compositions containing a chemical indicator therefor {(C12Q1/6897 takes precedence)} · CPC title

• G01N1/10

  in the liquid or fluent state {(burettes, pipettes B01L3/02; sampling of ground water E02D1/06; metering by volume of fluids or fluent solid material G01F11/00, G01F13/00)} · CPC title