MICROFLUIDIC DEVICE WITH SURFACE TENSION VALVE AT REAGENT RESERVOIR OUTLET

• US 20110312596A1
• Filed: 06/01/2011
• Published: 12/22/2011
• Est. Priority Date: 06/17/2010
• Status: Abandoned Application

• Current Assignee: Geneasys Pty Ltd
• Original Assignee: Geneasys Pty Ltd
• Inventors: Silverbrook, Kia, Azimi, Mehdi
• Application Number:
  US13/150,154
• Publication Number:
  US 20110312596A1
• Time in Patent Office: Days
• US Class Current: 506/16
• CPC Class Codes: B01L 2200/10 Integrating sample preparation and analysis in single entity, e.g. lab-on-a-chip concept
• CPC Class Codes: B01L 2300/023 Sending and receiving of information, e.g. using bluetooth
• CPC Class Codes: B01L 2300/024 Storing results with means integrated into the container
• CPC Class Codes: B01L 2300/0636 Integrated biosensor, microarrays
• CPC Class Codes: B01L 2300/0654 Lenses; Optical fibres
• CPC Class Codes: B01L 2300/0883 Serpentine channels
• CPC Class Codes: B01L 2300/10 Means to control humidity and/or other gases
• CPC Class Codes: B01L 2300/1827 using resistive heater
• CPC Class Codes: B01L 2400/0406 capillary forces
• CPC Class Codes: B01L 2400/0633 with moving parts
• CPC Class Codes: B01L 2400/0677 phase change valves; Meltable, freezing, dissolvable plugs; Destructible barriers
• CPC Class Codes: B01L 2400/0688 surface tension valves, capillary stop, capillary break
• CPC Class Codes: B01L 3/5027 by integrated microfluidic structures, i.e. dimensions of channels and chambers are such that surface tension forces are important, e.g. lab-on-a-chip B01L3/5023 takes precedence; micromixers B01F33/30; microreactors for synthesis B01J19/0093; microcapillary devices in general B81B1/00
• CPC Class Codes: B01L 3/502707 characterised by the manufacture of the container or its components by shaping or joining plastic parts B29C59/00, B29C65/00; by laminating B32B37/00; manufacture of microstructural devices in general B81C
• CPC Class Codes: B01L 3/502738 characterised by integrated valves microvalves F16K99/0001
• CPC Class Codes: B01L 7/52 with provision for submitting samples to a predetermined sequence of different temperatures, e.g. for treating nucleic acid samples amplification or hybridisation processes per se C12Q1/68; controlling sequential reactions for synthesis B01J19/0046
• CPC Class Codes: C12Q 1/68 involving nucleic acids
• CPC Class Codes: F16K 99/003 Valves for single use only
• CPC Class Codes: F16K 99/0036 operated by temperature variations
• CPC Class Codes: Y02A 90/10 Information and communication technologies [ICT] supporting adaptation to climate change, e.g. for weather forecasting or climate simulation
• CPC Class Codes: Y10T 137/0352 : Controlled by pressure
• CPC Class Codes: Y10T 137/0391 : Affecting flow by the addition of material or energy
• CPC Class Codes: Y10T 137/1044 : With other condition responsive valve control
• CPC Class Codes: Y10T 137/206 : Flow affected by fluid contact, energy field or coanda effect [e.g., pure fluid device or system]
• CPC Class Codes: Y10T 137/2076 : Utilizing diverse fluids
• CPC Class Codes: Y10T 137/2202 : By movable element
• CPC Class Codes: Y10T 436/107497 : Preparation composition [e.g., lysing or precipitation, etc.]
• CPC Class Codes: Y10T 436/11 : Automated chemical analysis
• CPC Class Codes: Y10T 436/143333 : Saccharide [e.g., DNA, etc.]
• CPC Class Codes: Y10T 436/145555 : Hetero-N
• CPC Class Codes: Y10T 436/173845 : Amine and quaternary ammonium
• CPC Class Codes: Y10T 436/203332 : Hydroxyl containing
• CPC Class Codes: Y10T 436/25 : including sample preparation
• 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 device for processing a fluid sample, the microfluidic device having a reservoir for containing a reagent, and, a surface tension valve having an aperture configured to pin a meniscus of the reagent such that the meniscus retains the reagent in the reagent reservoir until contact with the fluid sample removes the meniscus such that the reagent flows out of the reagent reservoir.

Claims

1. A microfluidic device for processing a fluid sample, the microfluidic device comprising:

a reservoir for containing a reagent; and

,

a surface tension valve having an aperture configured to pin a meniscus of the reagent such that the meniscus retains the reagent in the reagent reservoir until contact with the fluid sample removes the meniscus such that the reagent flows out of the reagent reservoir.

2. The microfluidic device according to claim 1 wherein the reservoir has a vent for ingress of air as the reagent flows out of the reagent reservoir.

3. The microfluidic device according to claim 2 further comprising a supporting substrate;

a microsystems technologies (MST) layer on the supporting substrate; and

,

a cap overlying the MST layer, the cap having a plurality of fluidic connections between the cap and the MST layer for fluid flow from the MST layer to the cap and fluid flow from the cap to the MST layer;

wherein,

at least one of the fluidic connections between the cap and the MST layer is the surface tension valve.

4. The microfluidic device according to claim 3 wherein the cap has a cap channel connecting at least two of the fluidic connections, the cap channel being configured to draw fluid flow between the fluidic connections by capillary action.

5. The microfluidic device according to claim 4 wherein the reagent reservoir is in fluid communication with the cap channel via the MST layer and at least two of the fluidic connections, one of the fluidic connections being the surface tension valve.

6. The microfluidic device according to claim 5 wherein the cap channel and the reagent reservoir are formed in a unitary layer of material.

7. The microfluidic device according to claim 6 wherein the cap channel is formed in one surface of the cap such that an outer surface of the MST layer encloses the cap channel.

8. The microfluidic device according to claim 7 wherein the cap has an exterior surface opposite said one surface, the exterior surface having a sample inlet for receiving the fluid sample and feeding the fluid sample to the cap channel.

9. The microfluidic device according to claim 8 wherein the fluid sample contains a biological sample including cells of different sizes, and at least one of the fluidic connections is an array of holes sized to prevent passage of cells larger than a predetermined threshold.

10. The microfluidic device according to claim 9 wherein the array of holes is part of a dialysis section, the dialysis section being configured for separating cells larger than a predetermined threshold into a portion of the sample which is processed separately from the remainder of the sample containing only cells smaller than the predetermined threshold.

11. The microfluidic device according to claim 10 wherein the biological sample is blood and the holes are configured such that cells smaller than the predetermined threshold include pathogens.

12. The microfluidic device according to claim 11 wherein the reagent in the reservoir is an anticoagulant and the cap is configured such that the anticoagulant is mixed with the blood prior to entering the dialysis section.

13. The microfluidic device according to claim 12 further comprising a lysis section in fluid communication with a lysis reagent reservoir containing a lysis reagent, the lysis section being configured to lyse pathogens and release genetic material within.

14. The microfluidic device according to claim 13 further comprising a nucleic acid amplification section for amplifying nucleic acid sequences in the fluid;

wherein the nucleic acid amplification section is a polymerase chain reaction (PCR) section and the cap has a PCR reagent reservoir containing dNTPs and primers for mixing with the sample prior to amplifying the nucleic acid sequences.

15. The microfluidic device according to claim 14 wherein the cap has a polymerase reservoir containing a polymerase for mixing with the fluid prior to amplifying the nucleic acid sequences.

16. The microfluidic device according to claim 15 further comprising CMOS circuitry positioned between the supporting substrate and the MST layer for operative control of the PCR section.

17. The microfluidic device according to claim 16 further comprising a hybridization section that has an array of probes for hybridization with target nucleic acid sequences amplified by the PCR section.

18. The microfluidic device according to claim 17 wherein the array has more than 1000 probes.

19. The microfluidic device according to claim 18 wherein the probes are fluorescent resonant energy transfer (FRET) probes and the CMOS circuitry further comprises an array of photodiodes for detecting hybridization of probes within the array of probes.

20. The microfluidic device according to claim 19 further comprising a plurality of heaters for controlling the temperature of the sample.