Abstract
On-chip concentration of samples using nanometer-sized structures fabricated in a microchannel is an effective method to improve detection sensitivity in μTAS. We proposed on-chip concentration of DNA samples using a nano-slit, which is a channel with a depth smaller than a diameter of DNA molecule. The concentration is based on an entropy trap at the boundary between the microchannel and the nano-slit. Therefore, concentration is achieved only by adjusting applied voltages. In this study, we verified the feasibility and the performances of the proposed concentration experimentally. When we applied 0.3 V for 100 s by using 30-nm deep nano-slit, we succeeded in concentration of λ DNA at 25 times the concentration rate.
