Chemical analytic apparatus and chemical analytic method

• US 8,372,658 B2
• Filed: 02/07/2012
• Issued: 02/12/2013
• Est. Priority Date: 01/15/2004
• Status: Expired due to Fees

• Current Assignee: Japan Science And Technology Agency
• Original Assignee: Japan Science And Technology Agency
• Inventors: Shikida, Mitsuhiro, Sato, Kazuo, Honda, Hiroyuki, Inouchi, Kohta
• Primary Examiner(s): Bullock, In Suk
• Assistant Examiner(s): Pregler, Sharon
• Application Number:
  US13/367,849
• Publication Number:
  US 20120135533A1
• Time in Patent Office: 371 Days
• Field of Search: 422/68.1, 422/500, 422/501, 422/502, 422/503, 422/504, 422/505, 422/506, 422/507, 422/508, 422/82.02, 422/82.05, 422/82.08, 422/58, 435/288.2, 435/287.2, 435/287.5, 205/98, 436/43, 436/150, 436/514, 436/518, 436/526, 436/501
• US Class Current: 436/501
• CPC Class Codes: B01L 2200/0647 Handling flowable solids, e.g. microscopic beads, cells, particles
• CPC Class Codes: B01L 2200/0673 Handling of plugs of fluid surrounded by immiscible fluid
• CPC Class Codes: B01L 2300/089 Virtual walls for guiding liquids
• CPC Class Codes: B01L 2400/043 magnetic forces
• CPC Class Codes: B01L 3/502761 specially adapted for handling suspended solids or molecules independently from the bulk fluid flow, e.g. for trapping or sorting beads, for physically stretching molecules investigating characteristics of particles G01N15/00
• CPC Class Codes: B01L 3/502784 specially adapted for droplet or plug flow, e.g. digital microfluidics automatic analysis using a stream of discrete samples in a tube system G01N35/08
• CPC Class Codes: B01L 3/502792 for moving individual droplets on a plate, e.g. by locally altering surface tension
• CPC Class Codes: Y10T 436/11 Automated chemical analysis

Abstract

A chemical analytic apparatus of the present invention is the one which proposes that a miniaturization, a making low-cost and portability are possible and also the operation of each process of separation, concentration and dilution of specimen is possible, and, which includes: an introduction means (S1) that introduces a droplet to which magnetic ultrafine particles are mixed into another liquid that differs from the droplet while maintaining a single droplet; a conveyance means by which the droplet that includes the magnetic particles is conveyed in another liquid of the introduction means by applying magnetic field externally to the magnetic ultrafine particles; and processing means (S2 to S6) by which operations for processing of chemical analysis are performed one by one in the process in which the droplet to which the magnetic ultrafine particles are mixed is conveyed by the conveyance means.

Claims

1. A chemical analytic method which performs various kinds of processing for chemically analyzing very small droplets, the method comprising the steps of;

introducing a droplet containing magnetic ultrafine particles into a first small compartment of a plurality of small compartments separated by plural projecting bulkheads;

conveying the droplet containing the magnetic ultrafine particles, through a stationary fluid by a magnetic force, the droplet passing beneath a first projecting bulkhead and into a second small compartment;

uniting the droplet containing the magnetic ultrafine particles, with at least another droplet which is stationary within the second small compartment;

conveying the united droplet to a from of a second projecting bulkhead by the magnetic force;

conveying via the magnetic force the united droplet beneath the second projecting bulkhead, wherein a main portion of the united droplet is unable to pass the second projecting bulkhead and only a peripheral portion of the united droplet that includes the magnetic ultrafine particles is conveyed by the magnetic force into a third small compartment such that the united droplet is separated and divided into a droplet including the magnetic ultrafine particles and a droplet that does not contain the magnetic ultrafine particles;

conveying via the magnetic force the divided droplet containing the magnetic ultrafine particles into a fourth small compartment containing at least a further droplet which is stationary within the fourth small compartment;

uniting the divided droplet with the magnetic ultrafine particles with the further droplet;

conveying via the magnetic force the further united droplet with the ultrafine magnetic particles into a small detection compartment to detect the result of the processing; and

discharging the further united droplet with the magnetic ultrafine particles from the small detection compartment.

2. The chemical analytic method according to claim 1, wherein

by controlling the magnetic force, said magnetic ultrafine particles contained in the droplet are dispersed and cohered in the inside of the droplet, and also a chemical reactive operation of a specimen for performing a chemical reactive operation that adhered to surfaces of said magnetic ultrafine particles is performed.

3. The chemical analytic method according to claim 2, wherein

other than the control of said magnetic force, at least physical and chemical reaction control by light, heat or pH is used.

4. The chemical analytic method according to claim 1, wherein

in the condition where a specimen for performing a chemical reactive operation is adhered to surfaces of said magnetic ultrafine particles, said magnetic ultrafine particles are used as a carrier to perform the chemical reactive operation to said specimen.

5. The chemical analytic method according to claim 1, wherein

by combining the plurality of small compartments, at least a series of chemical reactive operations by reaction, separation and dilution to a specimen that adhered to surfaces of said magnetic ultrafine particles is performed.

6. A chemical analytic method which performs various kinds of processing for chemically analyzing very small droplets, the method comprising steps of:

introducing a droplet containing specimens and magnetic ultrafine particles into a chemical analytic apparatus, the apparatus separated into plural small compartments communicating with each other and entirely filled with a liquid that is stationary in the apparatus, and the droplet containing the specimens and the magnetic ultrafine particles is introduced into the chemical analytic apparatus while maintaining a single droplet in the stationary liquid filling the apparatus, the droplet is immiscible with the liquid; and

conveying the droplet containing the specimens and the magnetic ultrafine particles that has been introduced into the apparatus through the stationary liquid in the apparatus, from one compartment to another compartment of the apparatus for performing processing for chemically analyzing the droplet, by moving a magnetic field generation device arranged adjacent to the apparatus in a direction in which the droplet is to be conveyed, the magnetic field generation device generating a magnetic field to which the magnetic ultrafine particles contained in the droplet are attracted.

7. The chemical analysis method according to claim 6, wherein the chemical analytic apparatus entirely filled with the liquid is separated into the plural small compartments communicating with each other by plural bulkheads projecting into the apparatus from a top side thereof.

8. The chemical analysis method according to claim 7, wherein the step of introducing the droplet containing specimens and magnetic ultrafine particles includes introducing the droplet containing the specimens and the magnetic ultrafine particles into a first small compartment of the plural small compartments, and

wherein the step of conveying the droplet containing the specimens and the magnetic ultrafine particles from one compartment to another compartment includes conveying the droplet containing the specimens and the magnetic ultrafine particles from the first small compartment to a second small compartment of the plural compartments, the droplet passing beneath a first projecting bulkhead of the plural bulkheads separating the first small compartment from the second small compartment, and uniting the droplet with a droplet of a reactive agent which is fixed in a fixed place within the second small compartment.

9. The chemical analysis method according to claim 8, wherein the step of conveying the droplet containing the specimens and the magnetic ultrafine particles from one compartment to another compartment further includes conveying the united droplet containing the specimens and the magnetic ultrafine particles from the second will compartment to a third small compartment of the plural compartments, the united droplet passing beneath a second projecting bulkhead of the plural bulkheads separating the second small compartment from the third small compartment, and separating and dividing the united droplet into a droplet containing the magnetic ultrafine particles and a droplet not containing the magnetic ultrafine particles, only the droplet containing the magnetic ultrafine particles conveyed to the third small compartment.

10. The chemical analysis method according, to claim 9, wherein the step of conveying the droplet containing the specimens and the magnetic ultrafine particles from one compartment to another compartment further includes conveying the divided droplet containing the magnetic ultrafine particles from the third small compartment into a fourth small compartment oldie plural compartments, the divided droplet passing beneath a third projecting bulkhead of the plural bulkheads separating the third small compartment from the fourth small compartment, and uniting the divided droplet with a droplet for dilution which is fixed in a fixed place within the fourth small compartment.

11. The chemical analysis method according to claim 10, wherein the step of conveying the droplet containing the specimens and the magnetic. ultrafine particles from one compartment to another compartment further includes conveying the further united droplet from the fourth small compartment into a fifth small compartment of the plural small compartments to detect as result of the processing.