Spatiotemporal fractionation of two DNA fragments by microfluidic devices

Microfluidics exhibit great promise as an alternative to conventional polyacrylamide slab gels to improve separation performance and decrease cross-contamination in the fractionation of selected DNA fragments from a complex mixture. This article provides a method to enable the spatial and temporal fractionation of multiple DNA fragments. We incorporate ten parallel extraction channels to increase the sampling range to cover multiple DNA fragments. Two neighboring fragments of 36, and 39 bases were first separated and simultaneously collected within 8 min. The ten recovered fractions were then analyzed by polymerase chain reaction amplification and capillary electrophoresis analysis. Six recovered DNA samples from the ten channels exhibited purities greater than 90 %, and two exhibited purities higher than 99 %. In contrast to a single extraction channel, this method also provides a better technical solution to high-throughput problems perceived to be more fundamental.