Microfluidic protein crystallography

• US 7,244,402 B2
• Filed: 08/07/2003
• Issued: 07/17/2007
• Est. Priority Date: 04/06/2001
• Status: Expired due to Fees

• Current Assignee: California Institute of Technology
• Original Assignee: California Institute of Technology
• Inventors: Quake, Stephen R., Hansen, Carl L., Sommer, Morten
• Primary Examiner(s): KUNEMUND, ROBERT M
• Application Number:
  US10/637,847
• Publication Number:
  US 20040115731A1
• Time in Patent Office: 1,440 Days
• Field of Search: 117/69, 422/245.1
• US Class Current: 422/245.1
• CPC Class Codes: B01J 19/0046 Sequential or parallel reactions, e.g. for the synthesis of polypeptides or polynucleotides; Apparatus and devices for combinatorial chemistry or for making molecular arrays synthesis methods per se C40B50/00
• CPC Class Codes: B01J 2219/00286 Reactor vessels with top and bottom openings
• CPC Class Codes: B01J 2219/00355 peristaltic
• CPC Class Codes: B01J 2219/00378 Piezoelectric or ink jet dispensers
• CPC Class Codes: B01J 2219/00396 Membrane valves
• CPC Class Codes: B01J 2219/00398 in multiple arrangements
• CPC Class Codes: B01J 2219/00439 using micromirror arrays
• CPC Class Codes: B01J 2219/005 Beads
• CPC Class Codes: B01J 2219/00527 Sheets
• CPC Class Codes: B01J 2219/0059 Sequential processes
• CPC Class Codes: B01J 2219/00605 the compounds being directly bound or immobilised to solid supports
• CPC Class Codes: B01J 2219/0061 The surface being organic
• CPC Class Codes: B01J 2219/00612 the surface being inorganic
• CPC Class Codes: B01J 2219/00659 Two-dimensional arrays
• CPC Class Codes: B01J 2219/00704 integrated with the reactor apparatus
• CPC Class Codes: B01J 2219/00707 separated from the reactor apparatus
• CPC Class Codes: B01J 2219/00722 Nucleotides
• CPC Class Codes: B01J 2219/00725 Peptides
• CPC Class Codes: B01J 2219/00756 Compositions, e.g. coatings, crystals, formulations
• 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 2200/0605 : Metering of fluids
• CPC Class Codes: B01L 2200/0673 : Handling of plugs of fluid surrounded by immiscible fluid
• 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 2300/0681 : Filter
• CPC Class Codes: B01L 2300/0861 : Configuration of multiple channels and/or chambers in a single devices
• CPC Class Codes: B01L 2300/123 : Flexible; Elastomeric
• CPC Class Codes: B01L 2300/14 : Means for pressure control
• CPC Class Codes: B01L 2300/18 : Means for temperature control
• CPC Class Codes: B01L 2400/0472 : Diffusion
• CPC Class Codes: B01L 2400/0481 : squeezing of channels or chambers
• CPC Class Codes: B01L 2400/0655 : pinch valves
• CPC Class Codes: B01L 2400/0688 : surface tension valves, capillary stop, capillary break
• CPC Class Codes: B01L 3/06 : Crystallising dishes
• 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 3/50273 : 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 7/54 : using spatial temperature gradients
• CPC Class Codes: B01L 9/527 : for microfluidic devices, e.g. used for lab-on-a-chip
• CPC Class Codes: C30B 29/54 : Organic compounds
• 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: C40B 40/10 : Libraries containing peptides or polypeptides, or derivatives thereof
• CPC Class Codes: F04B 43/043 : Micropumps
• CPC Class Codes: F04B 43/14 : having plate-like flexible members
• CPC Class Codes: F16K 2099/0074 : using photolithography, e.g. etching
• CPC Class Codes: F16K 2099/0078 : using moulding or stamping
• CPC Class Codes: F16K 2099/008 : Multi-layer fabrications
• CPC Class Codes: F16K 2099/0094 : Micropumps
• 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 99/0015 : Diaphragm or membrane valves
• CPC Class Codes: F16K 99/0028 : Valves having multiple inlets or outlets
• CPC Class Codes: F16K 99/0057 : the fluid being the circulating fluid itself, e.g. check valves
• CPC Class Codes: G01N 2013/003 : Diffusion; diffusivity between liquids

Abstract

The use of microfluidic structures enables high throughput screening of protein crystallization. In one embodiment, an integrated combinatoric mixing chip allows for precise metering of reagents to rapidly create a large number of potential crystallization conditions, with possible crystal formations observed on chip. In an alternative embodiment, the microfluidic structures may be utilized to explore phase space conditions of a particular protein crystallizing agent combination, thereby identifying promising conditions and allowing for subsequent focused attempts to obtain crystal growth.

Claims

1. An apparatus comprising:

a microfluidic flow channel network formed in a first elastomer layer, the microfluidic flow channel network comprising a first set of inlet branches in fluid communication with a junction and with a reagent source, a second set of inlet branches in fluid communication with the junction and with a buffer source, and a mixing structure in fluid communication with the junction and with an outlet;

a first control channel network formed in a second elastomer layer adjacent to the first elastomer layer, the first control channel network adjacent to the first inlet branch set to define a first multiplexer structure configured to flow a select reagent into the junction; and

a second control channel network formed in the second elastomer layer, the second control channel network adjacent to the second inlet branch set to define a second multiplexer structure configured to flow a select buffer into the junction.

2. The apparatus of claim 1 wherein the junction comprises a second flow channel intersecting a first flow channel at first and second points separated by a distance.

3. The apparatus of claim 2 wherein the first flow channel is branched along the distance.

4. The apparatus of claim 1 wherein the mixing structure comprises a closed circuit configured to be isolated from the junction and the outlet.

5. The apparatus of claim 1 wherein the mixing structure comprises a substantially circular shape.

6. The apparatus of claim 1 wherein the flow channel network further comprises an injector channel in fluid communication with the mixing structure.

7. The apparatus of claim 1 wherein the second elastomer layer defines at least three control channels overlying the flow channel network to define a peristaltic pumping structure configured to flow fluid through one of the first inlet branch set, the second inlet branch set, and the closed circuit.

8. The apparatus of claim 1 further comprising a sample storage structure in fluid communication with the outlet and configured to retain a sample from the mixing structure.

9. The apparatus of claim 8 wherein the sample storage structure comprises an elongated flow channel.

10. The apparatus of claim 9 wherein the elongated flow channel is dead-ended.

11. The apparatus of claim 10 wherein an end of the elongated flow channel opposite the inlet is gated by a valve.

12. The apparatus of claim 11 further comprising a multiplexer structure governing fluidic access to the elongated flow channel.

13. The apparatus of claim 9 wherein the storage structure comprises an array of storage vessels connected by rows and columns of flow channels.

14. The apparatus of claim 13 wherein the array of storage vessels comprises paired vessels in fluid communication through a valved connecting channel.