Microfluidic Polymer Valves

Technology Summary

In a technological breakthrough, Sandia researchers have developed polymer microvalves to allow fluids to be shuttled as easily in microfluidic chips as they are on a laboratory benchtop. The valves are photopatterned, cast-to-shape microscale polymer elements that can be used to isolate electric fields, and, as a consequence, locally isolate electroosmotic or electrophoretic flows. The valves can be actuated by applying pressure to move them inside a microfluidic channel in order to open and close flow pathways, isolating and manipulating the fluids of interest.

Description

Sandia’s isolated cast-in-place microvalves feature the only architecture currently available that enables control of high-pressure (350 bar) fluid flow in microchannels, while simultaneously controlling high-voltage (1 kV). Sandia’s microfluidic polymer valves enable micro-scale systems to apply high-pressure techniques with a wide range of chemical solvents while retaining easy control of microfluidic pathways. These valves are chemically inert, preventing adsorption of species on the valve surface, and enabling low-friction valve motion.

US Patents:

Patent # US 6,782,746 Mobile Monolithic Polymer Elements for Flow Control in Microfluidic Devices. Issued August 31, 2004. Inventors: Jason Rehm, Ernest Hasselbrink, Timothy Shepodd.

Patent # US 6,865,939 Fluorinated Silica Microchannel Surfaces. Issued March 3, 2005. Inventors: Brian Kirby, Timothy Shepodd.

Patent # US6, 952,962 Mobile Monolithic Polymer Elements for Flow Control on Microfluidic Devices. Issued Oct. 11, 2005. Inventors: Ernest Hasselbrink, Jason Rehm, Timothy Shepodd, Brian Kirby.

Patent # US 7,022,381 Method for Producing High Dielectric Strength Microvalves. Issued April 4, 2006. . Inventors: Brian Kirby, David Reichmuth, Timothy Shepodd.

Publications:

D.S. Reichmuth, T.J. Shepodd, B.J. Kirby. (2005). “Microchip HPLC of Peptides and Proteins,” Analytical Chemistry, vol 77(9), pp 2997-3000. [online]. Available: http://pubs.acs.org/doi/full/10.1021/ac048358r

 B.J. Kirby, D.S. Reichmuth, R.F. Renzi, T.J. Shepodd, B.W. Wiedenman.(2005).
“Microfluidic Routing of Aqueous and Organic Flows at High Pressures:Fabrication and Characterization of Integrated Polymer Microvalve Elements,” Lab on a Chip,  vol 5(2), pp 184-190. [online]. Available: http://www.kirbyresearch.com/pdf/200501kirbylabchip.pdf

 D.S. Reichmuth, T.J. Shepodd, B.J. Kirby. (2004).
“On-chip High-Pressure Picoliter Injector for Pressure-Driven Flow Through Porous Media,” Analytical Chemistry, vol 76(17), pp 5063-5068.[online]. Available: http://pubs.acs.org/doi/pdfplus/10.1021/ac0493572

 Brian J. Kirby and Timothy Shepodd.(2002).

“Microvalve Architectures for High-Pressure Hydraulic and Electrokinetic Fluid Control in Microchips”. MicroTAS 2002, Kluwer Academic Publishers, pp. 338-340. [online]. Available: http://www.sandia.gov/microfluidics/research/pdfs/utas02abs442kirby.pdf

 Brian Kirby, Timothy Shepodd, Ernest Hasselbrink. (2002). “Voltage-Addressable on/off Microvalves for High-Pressure Microchip Separations”. Journal of Chromatography. 979, pp 147-154. [online]. Available: http://www.sandia.gov/microfluidics/research/pdfs/200211kirbyvoltaddv.pdf

Ernest Hasselbrink, Timothy Shepodd, Jason Rehm. (2002).“High-Pressure Microfluidic Control in Lab-on-a-Chip Devices Using Mobile Polymer Monoliths”. Analytical Chemistry. 74, pp 4913-4918. [online]. Available:                        http://www.sandia.gov/microfluidics/research/pdfs/hasselb_anal_chem_valve.pdf

Jason Rehm, Timothy Shepodd, Ernest Hasselbrink. (2001).“Mobile Flow Control Elements for High-Pressure Micro-Analytical Systems Fabricated Using In-Situ Polymerization”. Micro Total Analysis Systems 2001, Kluwer Academic Publishers, 2001. [online]. Available: http://www.sandia.gov/microfluidics/research/pdfs/rehmutas2001.pdf

Presentations and abstracts:                                                                                                                        

D.S. Reichmuth, G.S. Chirica, B.J. Kirby

“Picoliter-Scale Proteomics Using an Integrated Microchip HPLC-MS/MS System,” AIChE 2004 Annual Meeting, Austin, Texas, November 2004. 

D.S. Reichmuth, G.S. Chirica, B.J. Kirby

“Analysis of Peptides Using An Integrated Microchip HPLC-MS/MS System,” Eighth International Conference on Miniaturized Systems for Chemistry and Life Sciences (MicroTAS 2004), Malmo, Sweden, September 2004.

 D.S. Reichmuth, T.J. Shepodd, B.J. Kirby

“On-chip Integration of Picoliter Injection Valving and Separation Media in a Microchip HPLC System,” HPLC 2004, Philadelphia, Pennsylvania, June 2004.

 D.S. Reichmuth, B.J. Kirby, T.J. Shepodd
“RP-HPLC Microchip Separations with Sub-Nanoliter On-Chip Pressure Injections,” Seventh International Symposium on Micro Total Analysis Systems (MicroTAS 2003), Squaw Valley, California, October 2003.

 B.J. Kirby, T.J. Shepodd, D.S. Reichmuth

“Metered Microchip Pressure Injections Using Mobile Polymer Monolith Microvalves,” HPCE 2003, San Diego, California, January 2003.

Benefits

• Effectively control both electrokinetic and high-pressure hydraulic flow.
• Greater process speeds using minuscule volumes of reagents, which saves money
• Significantly rapid response time (in milliseconds).
• Does not dissipate heat to the substrate
• Multiple microvalves may be placed on a chip for about 5 cents in materials cost
• Photopatterning the microvalves is rapid--only taking from 5 to 90 seconds.
• Valves can be operated in harsh, aggressive solvents as well as typical analytical solvents (such as water, methanol, and acetonitrile).
• No electrical power is dissipated into the fluid during valve operation.
• The microvalve dielectric strength is comparable to glass.
• Quantitative analysis is possible since common biochemical analytes neither react with nor adhere to valve surfaces.

Applications and Industries

• Miniaturization of gradient liquid chromatography analysis
• Chemical processing
• Chemical reactions
• Multi-dimensional separations
• Detection of biological and chemical agents
• Drug development
• Detection of trace chemical impurities
• Isolation, sorting, and manipulation of biological samples

Intellectual Property