Microfluidic system, sample analysis device, and target substance detection/measurement method

• US 7,863,054 B2
• Filed: 11/27/2006
• Issued: 01/04/2011
• Est. Priority Date: 11/28/2005
• Status: Active Grant

• Current Assignee: Seiko Epson Corporation (Seiko Group)
• Original Assignee: Seiko Epson Corporation (Seiko Group)
• Inventors: Takagi, Fumio
• Primary Examiner(s): Gordon; Brian R
• Application Number:
  US11/604,540
• Publication Number:
  US 20070120903A1
• Time in Patent Office: 1,499 Days
• Field of Search: 422/100, 436/180
• US Class Current: 436/180
• CPC Class Codes: B01L 2200/027 for microfluidic devices
• CPC Class Codes: B01L 2300/0816 Cards, e.g. flat sample carriers usually with flow in two horizontal directions
• CPC Class Codes: B01L 2400/027 electrostatic forces between substrate and tip
• CPC Class Codes: B01L 2400/0439 ultrasonic vibrations, vibrating piezo elements
• CPC Class Codes: B01L 2400/0487 fluid pressure, pneumatics
• CPC Class Codes: B01L 3/0268 using pulse dispensing or spraying, eg. inkjet type, piezo actuated ejection of droplets from capillaries
• CPC Class Codes: B01L 3/502715 characterised by interfacing components, e.g. fluidic, electrical, optical or mechanical interfaces
• CPC Class Codes: B01L 3/502746 characterised by the means for controlling flow resistance, e.g. flow controllers, baffles B01L3/502738 takes precedence
• CPC Class Codes: B01L 3/563 Joints or fittings in general F16L; Separable fluid transfer means to transfer fluids between at least two containers, e.g. connectors
• CPC Class Codes: Y10T 436/2575 Volumetric liquid transfer

Abstract

A microfluidic system includes a plate-shaped microfluidic chip having a flow path, a liquid introduction tube for supplying liquid to the flow path, the liquid introduction tube having an end communicating with an end of the flow path and its other end that can be soaked in the liquid that is to be supplied to the flow path, and a liquid discharge head communicating with the other end of the flow path for discharging liquid that has passed through the flow path.

Claims

1. A method for detecting or measuring a target substance in a sample solution by using a microfluidic system including:

a plate-shaped microfluidic chip having a flow path;

a liquid introduction tube for supplying liquid to the flow path, the liquid introduction tube having an end communicating with an end of the flow path and its other end that can be soaked in the liquid that is to be supplied to the flow path; and

a liquid discharge head communicating with the other end of the flow path for discharging liquid that has passed through the flow path,

wherein the flow path has a dam section having a narrower flow path diameter than other parts of the flow path,

the method comprising;

soaking an end of the liquid introduction tube opposite the end connected to the flow path in a solution containing beads each having a size preventing the beads passing through the dam section, with a substance having affinity for the target substance being immobilized to the surface of the beads,

activating the liquid discharge head, introducing the solution containing the beads into the flow path in the microfluidic chip, and damming the beads at the dam section;

soaking an end of the liquid introduction tube opposite the end connected to the flow path in the sample solution;

activating the liquid discharge head and introducing the sample solution into the flow path in the microfluidic chip to bring the sample solution in sufficient contact with the beads dammed at the dam section; and

detecting or measuring binding between the target substance and the substance having affinity for the target substance that has been immobilized to the bead surface.

2. The target substance detection/measurement method according to claim 1, further comprising, after bringing the sample solution in contact with the beads and before detecting or measuring binding, soaking the end of the liquid introduction tube opposite the end connected to the flow path in cleaning liquid and activating the liquid discharge head.

3. The target substance detection/measurement method according to claim 1, further comprising, after bringing the sample solution in contact with the beads and before detecting or measuring binding, soaking an end of the liquid introduction tube opposite the end connected to the flow path in a solution containing a labelled substance having affinity for the target substance, activating the liquid discharge head, and binding the target substance with the labelled substance.

4. The target substance detection/measurement method according to claim 1, wherein the liquid discharge head is operated to sequentially discharge droplets at 2-10 kHz.