Microfluidic devices for electrokinetically driven parallel and serial mixing

Microfabricated devices for parallel and serial mixing of fluids are demonstrated. To simplify the voltage control hardware, electrokinetic mixing is effected using a single voltage source with the channels dimensioned to perform the desired voltage division. In addition, the number of fluid reservoirs is reduced by terminating multiple buffer, sample, or analysis channels in single reservoirs. The parallel mixing device is designed with a series of independent T-intersections, and the serial mixing device is based on an array of cross intersections and sample shunting. These devices were tested by mixing a sample with buffer in a dilution experiment. Sample fractions of 1.0, 0.84, 0.67, 0.51, 0.36, 0.19, and 0 were generated for the parallel mixing device, and sample fractions of 1.0, 0.36, 0.21, 0.12, and 0.06 for the serial mixing device.