Multi-reservoir pressure control system

• US 20070157973A1
• Filed: 02/03/2007
• Published: 07/12/2007
• Est. Priority Date: 02/23/2000
• Status: Abandoned Application

• Current Assignee: Caliper Life Sciences Incorporated (Revvity, Inc.)
• Original Assignee: Caliper Life Sciences Incorporated (Revvity, Inc.)
• Inventors: Chow, Andrea, Chien, Ring-Ling, Parce, J., Kopf-Sill, Anne
• Application Number:
  US11/702,368
• Publication Number:
  US 20070157973A1
• Time in Patent Office: Days
• US Class Current: 137/565.290
• CPC Class Codes: B01L 2200/025 Align devices or objects to ensure defined positions relative to each other
• CPC Class Codes: B01L 2200/027 for microfluidic devices
• CPC Class Codes: B01L 2200/146 Employing pressure sensors
• CPC Class Codes: B01L 2300/0816 Cards, e.g. flat sample carriers usually with flow in two horizontal directions
• CPC Class Codes: B01L 2300/0867 Multiple inlets and one sample wells, e.g. mixing, dilution
• CPC Class Codes: B01L 2400/0415 electrical forces, e.g. electrokinetic
• CPC Class Codes: B01L 2400/0487 fluid pressure, pneumatics
• CPC Class Codes: B01L 2400/082 Active control of flow resistance, e.g. flow controllers
• CPC Class Codes: B01L 3/502715 characterised by interfacing components, e.g. fluidic, electrical, optical or mechanical interfaces
• CPC Class Codes: B01L 3/50273 characterised by the means or forces applied to move the fluids micropumps F04B19/006, of the membrane type F04B43/043
• CPC Class Codes: B01L 3/502738 characterised by integrated valves microvalves F16K99/0001
• 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 9/527 for microfluidic devices, e.g. used for lab-on-a-chip
• CPC Class Codes: G01N 11/08 by measuring pressure required to produce a known flow
• CPC Class Codes: G01N 2035/1044 Using pneumatic means
• CPC Class Codes: G01N 27/44791 Microapparatus sample containers with integrated microfluidic structures B01L3/5027
• CPC Class Codes: G05D 7/0694 by action on throttling means or flow sources of very small size, e.g. microfluidics microvalves F16K99/0001; microstructural devices per se B81B
• CPC Class Codes: Y10T 137/2076 Utilizing diverse fluids
• CPC Class Codes: Y10T 137/218 Means to regulate or vary operation of device
• CPC Class Codes: Y10T 137/86131 Plural

Abstract

Improved microfluidic devices, systems, and methods allow selective transportation of fluids within microfluidic channels of a microfluidic network by applying, controlling, and varying pressures at a plurality of reservoirs. Modeling the microfluidic network as a series of nodes connected together by channel segments and determining the flow resistance characteristics of the channel segments may allow calculation of fluid flows through the channel segments resulting from a given pressure configuration at the reservoirs. To effect a desired flow within a particular channel or series of channels, reservoir pressures may be identified using the network model. Viscometers or other flow sensors may measure flow characteristics within the channels, and the measured flow characteristics can be used to calculate pressures to generate a desired flow. Multi-reservoir pressure modulator and pressure controller systems can optionally be used in conjunction with electrokinetic or other fluid transport mechanisms.

Claims

1. A method of controlling the movement of fluid through an intersection between a first channel and a second channel in a microfluidic device, the method comprising:

applying a first pressure differential across the first channel with a first pressure source to, and

applying a second pressure differential across the second channel with a second pressure source.

2. The method of claim 1, wherein the first channel interfaces with two reservoirs on opposite sides of the intersection, wherein the second channel interfaces with two reservoirs on opposite sides of the intersection, wherein the first pressure source applies the first differential pressure across the two reservoirs interfacing with the first channel, and wherein the second pressure source applies the second pressure differential across the two reservoirs interfacing with the second channel.

3. The method of claim 2, wherein the two reservoirs interfacing with the first channel are at the termini of the first channel.

4. The method of claim 1, wherein the first and second channels have different flow resistances.

5. The method of claim 1, wherein the first and second pressure differentials are transmitted from the first and second pressure sources respectively through a pressure transmission system comprising lumens.

6. The method of claim 5, wherein the flow resistance of the lumens is less than the flow resistance of the first and less than the flow resistance of the second channel.

7. The method of claim 6, wherein the flow resistance of each of the first and second channels is at least ten times higher than the flow resistance of the pressure transmission system.

8. The method of claim 6, wherein the flow resistance of each of the first and second channels is at least one hundred times higher than the flow resistance of the pressure transmission system.

9. The method of claim 1, wherein the steps of applying the first and second pressure differentials further comprise the steps of measuring the first and second pressure differentials with first and second pressure sensors respectively.

10. The method of claim 9, wherein the steps of applying the first and second pressures further comprise providing feedback control to the first and second pressure sources.

11. The method of claim 1, wherein the first and second pressure sources are positive displacement pumps.

12. The method of claim 11, wherein the first and second pressure sources are syringes.

13. The method of claim 1, wherein each of the first and second channels comprise at least one fabricated dimension of less than 500μ

.

14. The method of claim 1, wherein the intersection is a cross intersection.

15. The method of claim 1, wherein the intersection is a “

T”

intersection.

16. The method of claim 1, wherein the microfluidic device comprises a silica-based substrate.

17. The method of claim 1, wherein the microfluidic device comprises a polymeric substrate.