Band broadening during high-throughput mutation detection in microchannels

Cycling temperature gradient electrophoresis represents a promising method for performing high-throughput DNA mutation detection in a microfluidic platform. Sweeping the temperature between an "all denatured" and "all annealed" state eliminates difficulties introduced by the low thermal mass of the system, while still preserving a mobility difference between the wild type and mutant alleles. We describe a theoretical analysis of this method of mutation detection, based on a multiple-time scales analysis that is valid when the DNA experience many temperature cycles before reaching the detector [1]. We focus on the band-broadening incurred by the interplay between the relaxation time of the chemical system and the thermal oscillations. New results are presented for the case where the denaturing and annealing reactions proceed at identical rates. Our analysis indicates that this separation would be best operated at low electric fields.