Implementation of microfluidic components, including molecular fractionation devices, in a microfluidic system

• US 20070075010A1
• Filed: 06/30/2006
• Published: 04/05/2007
• Est. Priority Date: 09/09/2002
• Status: Active Grant

• Current Assignee: Cytonome/St, Llc (Cytonome Inc.)
• Original Assignee: Cytonome Inc.
• Inventors: Deshpande, Manish, Gilbert, John, Trikha, Jaishree
• Granted Patent: US 7,514,000 B2
• Time in Patent Office: Days
• US Class Current: 210/321.600
• CPC Class Codes: B01D 2313/13 Specific connectors
• CPC Class Codes: B01D 2313/40 Adsorbents within the flow path
• CPC Class Codes: B01D 2325/028 Microfluidic pore structures
• CPC Class Codes: B01D 2325/12 Adsorbents being present on the surface of the membranes or in the pores
• CPC Class Codes: B01D 63/087 Single membrane modules
• CPC Class Codes: B01D 63/088 Microfluidic devices comprising semi-permeable flat membranes
• CPC Class Codes: B01D 67/0034 by micromachining techniques, e.g. using masking and etching steps, photolithography
• CPC Class Codes: B01D 67/0062 by micromachining techniques, e.g. using masking and etching steps, photolithography
• CPC Class Codes: B01L 2200/027 for microfluidic devices
• CPC Class Codes: B01L 2200/028 Modular arrangements
• CPC Class Codes: B01L 2200/146 Employing pressure sensors
• CPC Class Codes: B01L 2300/041 Connecting closures to device or container
• CPC Class Codes: B01L 2300/047 Additional chamber, reservoir
• CPC Class Codes: B01L 2300/0681 Filter
• CPC Class Codes: B01L 2300/0816 Cards, e.g. flat sample carriers usually with flow in two horizontal directions
• CPC Class Codes: B01L 2300/0874 Three dimensional network
• CPC Class Codes: B01L 2400/0421 electrophoretic flow
• CPC Class Codes: B01L 2400/0481 squeezing of channels or chambers
• CPC Class Codes: B01L 2400/0655 pinch valves
• CPC Class Codes: B01L 2400/0666 Solenoid valves
• CPC Class Codes: B01L 3/06 : Crystallising dishes
• 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 3/502715 : 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 3/502753 : characterised by bulk separation arrangements on lab-on-a-chip devices, e.g. for filtration or centrifugation separation in general B01D; microapparatus for analysis using electrophoresis G01N27/44791; sample preparation G01N1/28
• CPC Class Codes: C02F 2209/36 : Biological material, e.g. enzymes or ATP
• CPC Class Codes: C30B 29/58 : Macromolecular compounds
• CPC Class Codes: C30B 7/00 : Single-crystal growth from solutions using solvents which are liquid at normal temperature, e.g. aqueous solutions from molten solvents C30B9/00; by normal or gradient freezing C30B11/00; under a protective fluid C30B27/00
• CPC Class Codes: G01N 27/44743 : Introducing samples
• CPC Class Codes: G01N 27/44773 : Multi-stage electrophoresis, e.g. two-dimensional electrophoresis
• CPC Class Codes: Y10S 977/786 : Fluidic host/matrix containing nanomaterials
• CPC Class Codes: Y10T 156/10 : Methods of surface bonding and/or assembly therefor

Abstract

A system and method for integrating microfluidic components in a microfluidic system enables the microfluidic system to perform a selected microfluidic function. A capping module includes a microfluidic element for performing a microfluidic function. The capping module is stacked on a microfluidic substrate having microfluidic plumbing to incorporate the microfluidic function into the system. The microfluidic element may comprise a matrix having an affinity for selected molecules in a sample. The matrix binds, reacts with and/or retains the selected molecules without affecting other molecules in the sample.

Claims

1. A method for segregating molecules based on a selected property comprising the steps of:

providing a first molecular fractionation device including a matrix for binding molecules having the selected property,

flowing a sample containing molecules having the selected property through the matrix, such that molecules having the selected property are retained by the matrix, and

passing molecules not having the selected property through a first outlet of the molecular fractionation device.

2. The method of claim 1, further comprising the step of flowing a solution through the matrix, wherein the solution breaks a bond between the matrix and the retained molecules and passes the molecules having the selected property through a second outlet of the molecular fractionation device.

3. The method of claim 1, further comprising the step of:

separating the molecules having the selected property into a plurality of sub-fractions.

4. The method of claim 3, further comprising the step of:

releasing said plurality of sub-fractions into a microchannel via a second outlet of the device.

5. The method of claim 4, further comprising the step of ejecting one of said sub-fractions from the microchannel.

6. The method of claim 3, wherein the step of separating the molecules comprises the steps of:

flowing an elution buffer through the matrix; and

varying the composition of the elution buffer to separately release the sub-fractions from the matrix as bands of different affinity.

7. The method of claim 5, further comprising the step of electrophoretically separating one of said bands of different affinity into a plurality of sub-bands based on one of:

size, charge and charge/mass ratio using an electrophoretic column.

8. The method of claim 7, further comprising the step of ejecting one of said sub-bands from the electrophoretic column.

9. The method of claim 7, further comprising the step of separating a second of said bands into a plurality of different sub-bands after the second band is released from the matrix.

10. The method of claim 1, further comprising the steps of:

passing the retained molecules to a second molecular fractionation device including a second matrix for reacting with the molecules having the selected property.

11. The method of claim 10, wherein the molecules having the selected property comprises a protein, and the second matrix includes trypsin to digest the protein to form a peptide digest.

12. The method of claim 11, further comprising the step of:

passing the peptide digest to a third molecular fractionation device including a third matrix for retaining the peptide digest; and

retaining the peptide digest using the third matrix.

13. The method of claim 12, further comprising the steps of:

passing the peptide digest to a release channel; and

ejecting the peptide digest from the release channel.

14. A method of processing a sample, comprising the steps of:

providing a molecular fractionation device including a matrix having enzymes that react with selected fractions of the sample;

passing a buffer containing the sample through the molecular fractionation device, whereby the enzymes react with and process the selected fractions of the sample to form a reacted sample.

15. The method of claim 14, further comprising the step of:

passing the reacted sample through an outlet of the molecular fractionation device.

16. The method of claim 14, wherein the enzyme comprises trypsin, the sample comprises protein and the reacted sample contains trypsin digested proteins.

17. A method of analyzing a sample, comprising the steps of:

passing the sample through a molecular fractionation device including a matrix including detection molecules that react with the sample to produce a measurable reaction; and

detecting the measurable reaction.

18. The method of claim 17, further comprising the step of:

determining a quantity of the sample based on the step of detecting.

19. The method of claim 17, wherein the detection molecules react with a sample to produce light, or bind to the sample to produce shifts in optical fluorescence or optical absorbency of the detection molecules.

20. The method of claim 17, wherein the detection molecules comprise a luciferin-luciferase system, which emits photons when an ATP molecule is converted.

21. The method of claim 20, further comprising the step of determining a quantity of ATP present in the sample by measuring the photons emitted from the luciferin-luciferase system.

22. A method of fabricating a molecular fractionation device, comprising:

providing a capping module; and

bonding a trapping filter to the capping module to form a chamber for holding a matrix.

23. The method of claim 22, further comprising the step of:

inserting a matrix into the chamber.

24. The method of claim 23, further comprising the step of:

chemically modifying the matrix after the step of inserting the matrix into the chamber.

25. The method of claim 22, wherein the capping module includes a connector port for providing fluid communication between the chamber and an exterior of the capping module.

26. The method of claim 25, further comprising the step of:

assembling the capping module on a microfluidic chip including a microchannel formed in a substrate and a communication port coupling the microchannel to a surface of the substrate, such that the connector port of the capping module is in communication with the communication port of the microfluidic chip.

27. A microfluidic system, comprising:

a first channel for conveying a sample; and

a plurality of molecular fractionation devices coupled to the channel and arranged in series, such that a first outlet of a first molecular fractionation device is in communication with a first inlet of a second molecular fractionation device, wherein each molecular fractionation device includes a matrix having an affinity for a selected set of molecules.

28. A method for protein expression profiling, comprising:

fractionating a protein into a plurality of fractions using a plurality of molecular fractionation devices, wherein each molecular fractionation device includes a matrix having an affinity for one of said fractions; and

eluting each of said plurality of fractions from the molecular fractionation devices as bands of different affinities.

29. The method of claim 28, further comprising the step of dialyzing the eluted bands using a semipermeable membrane.

30. The method of claim 29, further comprising the step of injecting one of said eluted bands into a capillary electrophoresis column.

31. The method of claim 30, further comprising the step of electrophoretically separating said band into a plurality of sub-bands.

32. The method of claim 31, further comprising the step of ejecting one of said sub-bands from the electrophoresis column to a plate.

33. The method of claim 32, wherein the sub-band is ejected to one of a multiwell plate and a MALDI spotting plate.