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Microfluidic Temperature Gradient Focusing



David J. Ross, Laurie E. Locascio


A new technique is described for the concentration and separation of ionic species in a microchannels. Concentration is achieved by balancing the electrophoretic velocity of an analyte against the bulk flow of solution in the presence of a temperature gradient. With an appropriate buffer, the temperature gradient can generate a corresponding gradient in the electrophoretic velocity, so that the electrophoretic and bulk velocities sum to zero at a unique point, resulting in analyte focusing. The technique for a variety of analytes including, amino acids, DNA, proteins, and particles, is shown to be capable of greater than 10000-fold concentration.
Analytical Chemistry
No. 11


focusing, microfluidics, preconcentration


Ross, D. and Locascio, L. (2002), Microfluidic Temperature Gradient Focusing, Analytical Chemistry (Accessed July 18, 2024)


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Created June 1, 2002, Updated February 17, 2017