Microfluidic system including a bubble valve for regulating fluid flow through a microchannel

• US 8,623,295 B2
• Filed: 09/26/2011
• Issued: 01/07/2014
• Est. Priority Date: 04/17/2002
• Status: Expired due to Term

• Current Assignee: Cytonome/St, Llc (Cytonome Inc.)
• Original Assignee: Cytonome/St, Llc (Cytonome Inc.)
• Inventors: Gilbert, John Richard, Bhm, Sebastian, Deshpande, Manish
• Primary Examiner(s): Hyun, Paul
• Application Number:
  US13/245,331
• Publication Number:
  US 20120015442A1
• Time in Patent Office: 834 Days
• Field of Search: 422/537, 422502-504
• US Class Current: 422/503
• CPC Class Codes: B01L 2200/0636 Focussing flows, e.g. to laminate flows
• CPC Class Codes: B01L 2200/0647 Handling flowable solids, e.g. microscopic beads, cells, particles
• CPC Class Codes: B01L 2300/0816 Cards, e.g. flat sample carriers usually with flow in two horizontal directions
• CPC Class Codes: B01L 2300/0864 comprising only one inlet and multiple receiving wells, e.g. for separation, splitting
• CPC Class Codes: B01L 2300/089 Virtual walls for guiding liquids
• CPC Class Codes: B01L 2400/0415 electrical forces, e.g. electrokinetic
• CPC Class Codes: B01L 2400/06 Valves, specific forms thereof
• CPC Class Codes: B01L 2400/0688 surface tension valves, capillary stop, capillary break
• CPC Class Codes: B01L 2400/082 Active control of flow resistance, e.g. flow controllers
• CPC Class Codes: B01L 3/502738 characterised by integrated valves microvalves F16K99/0001
• 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 3/502776 specially adapted for focusing or laminating flows
• CPC Class Codes: B07C 5/34 Sorting according to other particular properties material testing per se G01N; quality control G07C3/14
• CPC Class Codes: F16K 2099/0074 using photolithography, e.g. etching
• CPC Class Codes: F16K 2099/008 Multi-layer fabrications
• CPC Class Codes: F16K 2099/0084 Chemistry or biology, e.g. "lab-on-a-chip" technology
• CPC Class Codes: F16K 99/0001 Microvalves microdevices B81B1/00; manufacture or treatment of devices or systems in or on a substrate B81C1/00; microfluidic structures B01L3/5027; micropumps F04B19/006
• CPC Class Codes: F16K 99/0017 Capillary or surface tension valves, e.g. using electro-wetting or electro-capillarity effects
• CPC Class Codes: F16K 99/0019 Valves using a microdroplet or microbubble as the valve member
• CPC Class Codes: F16K 99/0034 Operating means specially adapted for microvalves
• CPC Class Codes: F16K 99/0036 : operated by temperature variations
• CPC Class Codes: F16K 99/004 : using radiation
• CPC Class Codes: F16K 99/0046 : using magnets
• CPC Class Codes: F16K 99/0048 : using piezoelectric means
• CPC Class Codes: G01N 15/149 : specially adapted for sorting particles, e.g. by their size or optical properties
• CPC Class Codes: Y10T 137/0318 : Processes
• CPC Class Codes: Y10T 137/0396 : Involving pressure control
• CPC Class Codes: Y10T 137/0497 : Fluid actuated or retarded
• CPC Class Codes: Y10T 137/2076 : Utilizing diverse fluids
• CPC Class Codes: Y10T 137/2082 : Utilizing particular fluid
• CPC Class Codes: Y10T 137/2191 : By non-fluid energy field affecting input [e.g., transducer]
• CPC Class Codes: Y10T 137/2196 : Acoustical or thermal energy
• CPC Class Codes: Y10T 137/2202 : By movable element
• CPC Class Codes: Y10T 137/2207 : Operating at timed intervals [e.g., to produce pulses]
• CPC Class Codes: Y10T 137/2213 : Electrically-actuated element [e.g., electro-mechanical transducer]
• CPC Class Codes: Y10T 137/2224 : Structure of body of device
• CPC Class Codes: Y10T 29/49405 : Valve or choke making
• CPC Class Codes: Y10T 436/143333 : Saccharide [e.g., DNA, etc.]
• CPC Class Codes: Y10T 436/25375 : Liberation or purification of sample or separation of material from a sample [e.g., filtering, centrifuging, etc.]

Abstract

A microfluidic system includes a bubble valve for regulating fluid flow through a microchannel. The bubble valve includes a fluid meniscus interfacing the microchannel interior and an actuator for deflecting the membrane into the microchannel interior to regulate fluid flow. The actuator generates a gas bubble in a liquid in the microchannel when a sufficient pressure is generated on the membrane.

Claims

1. A microfluidic system comprising:

a microfluidic flow channel formed in a substrate and adapted to facilitate analysis or processing of a sample having one or more particles suspended in a suspension medium flowing through the flow channel;

a first reservoir operatively associated with the flow channel and adapted for dampening or absorbing a pressure pulse propagated across the flow channel; and

a second reservoir operatively associated with the flow channel and adapted for generating the pressure pulse based on a change in volume or pressure in the second reservoir;

wherein the flow channel defines a first aperture for connecting the flow channel relative to the first reservoir and a second aperture for connecting the flow channel relative to the second reservoir, wherein the first aperture is substantially opposite the second aperture.

2. The system of claim 1 further comprising an actuator or pressurizer operatively associated with the second reservoir and adapted for generating the pressure pulse by varying the volume or pressure in the second reservoir.

3. The system of claim 1, wherein the flow channel includes a branched portion, wherein the pressure pulse is used to sort one or more particles into a selected branch of the branched portion.

4. The system of claim 1, wherein the first reservoir includes a gas pocket, wherein compression of the gas facilitates the dampening or absorbing of the pressure pulse.

5. The system of claim 4, further comprising a fluid filled region interfacing with the flow channel and the gas pocket.

6. The system of claim 5, wherein the fluid filled region includes a portion of the first reservoir.

7. The system of claim 5, wherein the fluid filled region includes a side channel connecting the first reservoir to the flow channel.

8. The system of claim 5, wherein the fluid filled region prevents the gas from the gas pocket from leaking into the flow channel.

9. The system of claim 1, wherein the first reservoir includes a resilient wall for facilitating dampening or absorbing of the pressure pulse.

10. The system of claim 1, wherein the second reservoir includes a gas pocket, wherein compression of the gas facilitates the generating of the pressure pulse.

11. The system of claim 10 further comprising a fluid filled region interfacing with the flow channel and the gas pocket.

12. The system of claim 11, wherein the fluid filled region includes a portion of the second reservoir.

13. The system of claim 11, wherein the fluid filled region includes a side channel connecting the second reservoir to the flow channel.

14. The system of claim 11, wherein the fluid filled region prevents the gas from the gas pocket from leaking into the flow channel.

15. The system of claim 11, wherein the fluid filled region forms a meniscus with the gas pocket.

16. The system of claim 15, wherein the change in volume or pressure in the second reservoir deflects the meniscus into the flow channel.

17. The system of claim 1, wherein the second reservoir includes a deflectable flexible membrane wherein deflection of the membrane increases the pressure in the second reservoir.

18. The system of claim 1, wherein the change in volume or pressure in the second reservoir is a transient change in volume or pressure.