Electrokinetic Micropumps

Sandia National Laboratories, Livermore

Electrokinetic micropumps (EK pumps) use electroosmosis in charged porous media to generate pressure and flow in microdevices. EK pumps are realized by applying voltage across a porous bed, typically a monolithic porous polymer or a bed of packed silica particles.

Electrokinetic pumps have no moving parts, excellent frequency response, and the ability to precisely meter at high-pressure and low flow rates.

Work at Sandia on electrokinetic pumps has been ongoing for several years, and has included demonstration of pressures over 8000 psi and efficiencies over 5%, use for mechanical actuation of microvalves, and use for miniaturized high-pressure liquid chromatography.

Presentations

D.S. Reichmuth, G.S. Chirica, B.J. Kirby
"Improving Electrokinetic Pump Performance for Microchip HPLC, " oral presentation HPCE 2003,
January 2003, San Diego, CA.

S.K. Griffiths and R.H. Nilson
"Optimization of Electrokinetic Pumps for Chip-Based Chromatographic Separations," MicroTAS 2002, November, 2002, Nara, Japan.

References

D.S. Reichmuth, B.J. Kirby, SAND2002-8385J
"Effects of Ammonioalkyl sulfonate internal salts on electrokinetic micropump performance and reversed-phase high-performance liquid chromatographic separations," J. Chrom. A, 1013 (2003) p93-101.

D.S. Reichmuth, G.S. Chirica, B.J. Kirby, SAND2002-8622C
"Increasing the performance of high-pressure, high-efficiency electrokinetic micropumps using zwitterionic solute additives," Sens. Act. B., 92 (2003) p37-43.

S.K. Griffiths and R.H. Nilson
"Optimization of Electrokinetic Pumps for Chip-Based Chromatographic Separations,"
in MicroTAS 2002 , Kluwer Academic Publishers, 2002.

P.H. Paul, D.W. Arnold, D.W. Neyer, K.B. Smith
"Electrokinetic pump application in micro-total analysis systems: Mechanical actuation to HPLC,"
in MicroTAS 2000 , Kluwer Academic Publishers, p. 97, 2000.

P.H. Paul, D.W. Arnold, D.J. Rakestraw
"Electrokinetic generation of high pressures using porous microstructures,"
in MicroTAS '98 , Kluwer Academic Publishers, 1998.