Fluid transfer mechanism

• US 8,182,765 B2
• Filed: 02/15/2007
• Issued: 05/22/2012
• Est. Priority Date: 02/21/2006
• Status: Active Grant

• Current Assignee: Universal Biosensors Pty Ltd. (Universal Biosensors, Inc.)
• Original Assignee: Universal Biosensors Pty Ltd. (Universal Biosensors, Inc.)
• Inventors: Chatelier, Ronald Christopher, Hodges, Alastair Mcindoe, Chambers, Garry
• Primary Examiner(s): Sines, Brian J
• Application Number:
  US12/280,317
• Publication Number:
  US 20090305431A1
• Time in Patent Office: 1,923 Days
• Field of Search: 422/68.1, 422/100, 422/102, 422/502, 422/503, 422/504, 422/507, 436/180
• US Class Current: 422/502
• CPC Class Codes: B01L 2200/143 Quality control, feedback systems
• CPC Class Codes: B01L 2300/0645 Electrodes
• CPC Class Codes: B01L 2300/0816 Cards, e.g. flat sample carriers usually with flow in two horizontal directions
• CPC Class Codes: B01L 2300/0825 Test strips
• CPC Class Codes: B01L 2300/0874 Three dimensional network
• CPC Class Codes: B01L 2300/0887 Laminated structure
• CPC Class Codes: B01L 2400/0406 capillary forces
• CPC Class Codes: B01L 2400/0487 fluid pressure, pneumatics
• CPC Class Codes: B01L 2400/0688 surface tension valves, capillary stop, capillary break
• CPC Class Codes: B01L 3/502738 characterised by integrated valves microvalves F16K99/0001
• CPC Class Codes: F16K 2099/008 Multi-layer fabrications
• CPC Class Codes: F16K 2099/0086 Medical applications
• 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 99/0025 Valves using microporous membranes
• CPC Class Codes: Y10T 436/25 including sample preparation
• CPC Class Codes: Y10T 436/2575 Volumetric liquid transfer

Abstract

A microfluidic device for transferring liquid from a first chamber to a second chamber is provided. The device has a first chamber; a second chamber; and a barrier between the first chamber and the second chamber, the barrier having least one opening fluidly connecting the first chamber to the second chamber, the at least one opening being sized such that a retention force, such as surface tension, keeps the liquid in the first chamber. The fluid is transferred from the first chamber to the second chamber when an initiation input such as fluid pressure is introduced to the liquid that is sufficient to overcome the retention force. The device may be a sensor strip.

Claims

1. A fluid transfer device for transferring a fluid from a first chamber to a second chamber, the device comprising:

a first chamber;

a second chamber; and

a barrier layer between the first chamber and the second chamber, the barrier layer having at least one opening fluidly connecting the first chamber to the second chamber, the at least one opening defining a fluid pathway from the first chamber to the second chamber, the at least one opening being sized such that a retention force keeps the fluid in the first chamber and the at least one opening,

wherein at least a portion of the second chamber is movable with respect to the barrier layer, and

wherein the fluid can be transferred from the first chamber to the second chamber via the fluid pathway when an initiation input is introduced to the device such that the portion of the second chamber contacts the fluid at the at least one opening.

2. The device of claim 1, wherein the retention force comprises surface tension of the fluid at the at least one opening.

3. The device of claim 2, wherein the second chamber has an inner surface and an outer surface, wherein at least a portion of the inner surface of the second chamber is movable with respect to the barrier layer, and

the initiation input comprises pressure applied to the outer surface of the second chamber such that the portion of the inner surface of the second chamber contacts the fluid at the at least one opening and causes the fluid to flow via the fluid pathway into the second chamber.

4. The device of claim 1, wherein the device is a sensor strip,

the first chamber is a reaction chamber of the sensor strip, and

the second chamber is a detection chamber of the sensor strip.

5. The device of claim 1, further comprising

a third chamber;

and

a second barrier layer between the second chamber and the third chamber, the second barrier layer having at least one opening fluidly connecting the second chamber to the third chamber, the at least one opening defining a second fluid pathway from the second chamber to the third chamber, the at least one opening in the second barrier layer being sized such that a second retention force keeps the fluid in the second chamber and the at least one opening in the second barrier layer,

wherein at least a portion of the third chamber is movable with respect to the second barrier layer, and

wherein the fluid can be transferred between the second chamber and the third chamber via the second fluid pathway when a second initiation input is introduced such that the portion of the third chamber contacts the fluid at the at least one opening in the second barrier layer.

6. The device of claim 5, wherein the second retention force comprises surface tension of the fluid at the at least one opening in the second barrier layer.

7. The device of claim 6, wherein the third chamber has an inner surface and an outer surface, wherein at least a portion of the inner surface of the third chamber is movable with respect to the second barrier layer, and

the second initiation input comprises pressure applied to the outer surface of the third chamber such that the portion of the inner surface of the third chamber contacts the fluid in the at least one opening in the second barrier layer and causes the fluid to flow via the second fluid pathway in the second barrier layer into the third chamber.

8. The device of claim 5, wherein the device is a sensor strip,

the first chamber is a reaction chamber of the sensor strip,

the second chamber is a transfer and reaction chamber of the sensor strip, and

the third chamber is a detection chamber of the sensor strip.

9. A method of transferring a fluid from a first chamber to a second chamber using the fluid transfer device of claim 1, comprising:

providing a first chamber;

providing a second chamber;

providing a barrier layer between the first chamber and the second chamber, the barrier layer having at least one opening fluidly connecting the first chamber to the second chamber, the at least one opening defining a fluid pathway from the first chamber to the second chamber, the at least one opening being sized such that a retention force keeps the fluid in the first chamber and the at least one opening in the barrier layer;

introducing the fluid to the first chamber to at least partially wet the barrier layer at the at least one opening;

transferring the fluid from the first chamber to the second chamber via the fluid pathway,

wherein the transferring takes place when an initiation input is introduced such that a portion of the second chamber contacts the fluid at the at least one opening in the barrier layer, and

wherein the portion of the second chamber is movable with respect to the barrier layer.

10. The method of claim 9, wherein the retention force comprises surface tension of the fluid at the at least one opening.

11. The method of claim 10, wherein the initiation input comprises fluid pressure applied to the fluid in the at least one opening and in a direction from the first chamber to the second chamber.

12. The method of claim 10, wherein the initiation input comprises pressure applied to an outer surface of the second chamber such that an inner surface of the second chamber contacts the fluid in the at least one opening and causes the fluid to flow via the fluid pathway into the second chamber, wherein the inner surface of the second chamber is not coplanar with the barrier layer.

13. The method of claim 9, wherein the first chamber is a reaction chamber of a sensor strip, and

the second chamber is a detection chamber of the sensor strip.

14. The method of claim 9, further comprising

providing a third chamber;

providing a second barrier layer between the second chamber and the third chamber, the second barrier layer having at least one opening fluidly connecting the second chamber to the third chamber, the at least one opening defining a second fluid pathway from the second chamber to the third chamber, the at least one opening in the second barrier layer being sized such that a second retention force keeps the fluid in the second chamber and the at least one opening in the second barrier layer; and

transferring the fluid from the second chamber to the third chamber via the second fluid pathway,

wherein the transferring between the second chamber and the third chamber takes place when a second initiation input is introduced such that a portion of the third chamber contacts the fluid at the at least one opening in the second barrier layer, and

wherein the portion of the third chamber is movable with respect to the second barrier layer.

15. The method of claim 14, wherein the second retention force comprises surface tension of the fluid at the at least one opening in the second barrier layer.

16. The method of claim 15, wherein the second initiation input comprises fluid pressure applied to the fluid in the at least one opening in the second barrier layer and in a direction from the second chamber to the third chamber.

17. The method of claim 15, wherein the second initiation input comprises pressure applied to an outer surface of the third chamber such that an inner surface of the third chamber contacts the fluid in the at least one opening in the second barrier layer and causes the fluid to flow via the second fluid pathway in the second barrier layer into the third chamber, wherein the inner surface of the third chamber is not coplanar with the second barrier layer.

18. The method of claim 14, wherein the first chamber is a reaction chamber of a sensor strip,

the second chamber is a transfer and reaction chamber of the sensor strip;

and

the third chamber is a detection chamber of the sensor strip.

19. The device of claim 1, wherein the barrier layer comprises an electrode.

20. The device of claim 1, wherein the movable portion of the second chamber comprises an electrode.

21. The device of claim 1, wherein the first chamber and the second chamber are stacked.

22. The device of claim 21, wherein the first chamber and the second chamber are offset.

23. The device of claim 21, wherein the first chamber and the second chamber are at least partially overlapping.

24. The device of claim 1, wherein the device is an disposable immunoassay strip.

25. The device of claim 1 further comprising a filling chamber, wherein the fluid can be transferred from the filling chamber to the first chamber via capillary action.

26. The device of claim 25, wherein the filling chamber has a larger volume than the first chamber.

27. The device of claim 24, wherein the strip is formed from a plurality of layers, and the first and second chambers being formed in separate layers.

28. The method of claim 9, wherein the transferring the fluid from the first chamber to the second chamber via the fluid pathway comprises

deflecting the movable portion of the second chamber to contact the fluid at the at least one opening, thereby drawing the fluid into the second chamber.

29. The method of claim 9 comprising:

providing a first and second electrode layer either side of the second chamber; and

electrically connecting the first and second electrode layers to a meter.

30. The method of claim 29 further comprising

measuring an electrical property of the second chamber using the first and second electrode layer to determine a fill state of the second chamber.