摘要

A new paper-based microfluidic switch activated by surface acoustic wave (SAW) was presented. The switch was comprised of two folded paper microchannels and an unfolded paper microchannel. One of the folded paper microchannels was connected with the unfolded paper microchannel. Two interdigital transducers (IDTs) and two reflectors were fabricated on 128 degrees yx-LiNbO3 substrate using microelectrical technology. When an amplified RF signal was applied to the IDTs, a droplet on the piezoelectric substrate was actuated to the unfolded paper microchannel by SAW. Folded angle of a folded paper microchannel was increased and connected with the other folded paper microchannel to implement 'on' function of the microfluidic switch. The switch was examined using red dye solution microfluids and mixed indicating solution of 330 mmol/L Citric acidmonohydrate, 10 mmol/L N-(1-Naphthyl) ethylenediamine dihydrochloride and 50 mmol/L Sulfanilamide. The presented switch is valuable for programmable paper-based microfluidic device for multiple sample analyses.