Abstract
Microfluidic system has superior controllability of fluidics. Herein we have developed a novel separation method for the complexes formed in microchannel, and application for DNA sensor. This method is based on the molecular sieving effect which is achieved by the superior controllability of fluidics. By the use of confocal fluorescence microscopy observation and computer simulation, we have confirmed that the laminar secondary flow at the curing part of microchannel enables this microfluidic separation. Also in this study, we have applied this molecular sieving effect for sequence-selective DNA sensor. As the result of this measurement, the response of complementary sequence target DNA was higher than non-complementary sequence. Moreover, in comparison with different length complementary sequence target, the response of longer target was higher. This method does not require immobilization of probe or target DNA, just simply inject solutions into microchannel and all reactions performed in the liquid phase. Such features might enable lowering the experimental error and difference in data by operators.
