Method for trapping microparticle and microparticle trapping device

Patent metadata

Field	Value
Publication number	US-12474297-B2
Application number	US-202117547377-A
Country	US
Kind code	B2
Filing date	Dec 10, 2021
Priority date	Dec 14, 2020
Publication date	Nov 18, 2025
Grant date	Nov 18, 2025

Abstract

A microparticle trapping device includes: a fluid channel configured to be injected with a fluid including a microparticle; first and second electrodes configured to generate an electric field in the fluid channel; and an electrical insulator formed with at least one opening between the first and second electrodes in the fluid channel. The electrical insulator is disposed between the first and second electrodes so that an inhomogeneous electric field is made through the at least one opening between the first and second electrodes in the fluid channel, and the still other aspect is configured to trap the microparticle through dielectrophoresis.

First claim

What is claimed is:

1 . A method for trapping a microparticle through dielectrophoresis, the method comprising:
preparing a fluid channel, first and second electrodes configured to generate an electric field in the fluid channel, and an electrical insulator including two partition walls intersecting each other, each of the two partition walls including an opening formed in the fluid channel between the first electrode and the second electrode; injecting a fluid including the microparticle into the fluid channel; and applying a voltage to the first and second electrodes so that an inhomogeneous electric field is made through the opening between the first and second electrodes in the fluid channel, wherein the first electrode includes a first pair of electrodes opposing each other in a first direction, the second electrode includes a second pair of electrodes opposing each other in a second direction intersecting the first direction, the preparing a fluid channel, first and second electrodes comprises preparing a housing for the fluid channel, the housing including a base and a wall defining the fluid channel with the base, the first and second electrodes being disposed on the base, the electrical insulator being disposed on the wall, preparing the two partition walls to form four divisions in the fluid channel, and four electrodes including the first pair of electrodes and the second pair of electrodes, each of the four electrodes being disposed at one of the four divisions, and the injecting a fluid comprises injecting the fluid including the microparticle into the fluid channel so that the microparticle comes in contact with the four electrodes, and disposing the wall on the base so that the opening is positioned in the fluid including the microparticle.

2 . A method for analyzing a microparticle, the method comprising:
trapping the microparticle through the method according to claim 1 ; irradiating the trapped microparticle with first light; and detecting second light from the microparticle, the second light being emitted due to irradiation to the microparticle with the first light.

3 . The method according to claim 2 , wherein
the trapping the microparticle comprises preparing the electrical insulator transparent to the first light and the second light.

4 . The method according to claim 2 , wherein
the detecting second light comprises detecting fluorescence from the microparticle, the fluorescence being emitted due to the irradiation with the first light.

5 . A microparticle trapping device, comprising:
a fluid channel configured to be injected with a fluid including a microparticle; first and second electrodes configured to generate an electric field in the fluid channel; an electrical insulator including two partition walls intersecting each other, each of the two partition walls including an opening formed in the fluid channel between the first electrode and the second electrode; and a housing including a base and a wall defining the fluid channel with the base, the first and second electrodes being disposed on the base, the electrical insulator being disposed on the wall, wherein the first electrode includes a first pair of electrodes opposing each other in a first direction, the second electrode includes a second pair of electrodes opposing each other in a second direction intersecting the first direction, and wherein the two partition walls form four divisions in the fluid channel, each of the four electrodes including the first pair of electrodes and the second pair of electrodes, being disposed at one of the four divisions.

6 . A microparticle analysis device comprising:
the microparticle trapping device according to claim 5 ; a light irradiation unit configured to irradiate the microparticle trapped around the opening with first light; and a light detection unit configured to detect second light from the microparticle, the second light being emitted due to irradiation to the microparticle with the first light.

7 . The microparticle analysis device according to claim 6 , wherein
the electrical insulator is transparent to the first light and the second light.

8 . The microparticle analysis device according to claim 6 , wherein
the light detection unit is configured to detect fluorescence from the microparticle, the fluorescence being emitted due to the irradiation with the first light.

Assignees

• Hamamatsu Photonics Kk

Inventors

• Kimura Yuji
• Suzuki Kazuya
• Makino Ryo
• Itoh Hiroyasu

Classifications

• B03C5/005

  Dielectrophoresis, i.e. dielectric particles migrating towards the region of highest field strength · CPC title

• B03C5/022

  Non-uniform field separators · CPC title

• G01N2021/6495

  Miscellaneous methods · CPC title

• G01N21/64

  Fluorescence; Phosphorescence · CPC title

• G01N15/01

  specially adapted for biological cells, e.g. blood cells (investigating sedimentation of particle suspensions in blood G01N15/05) · CPC title