声表面波实现微流体垂向输运

Transporting Microfluids in Vertical Direction Using Surface Acoustic Wave

提出了声表面波实现微流体垂向输运方法,使得纸基微流器件具有前处理操作功能。在1280旋转Y切割X传播方向的LiNbO3基片上光刻叉指换能器对和反射栅,纸基微流器件通过贴合于压电基片表面的PDMS置放于距压电基片上方2 mm处,经功率放大器放大的RF信号加到叉指换能器对上,激发的两相声表面波使得压电基片上待分析微流体垂向运动并到达纸基片实现纸基微流分析。采用不同体积红色染料溶液微流体进行了垂向输运实验。结果表明:纸基片距压电基片一定间距时,实现压电基片上待分析微流体垂向输运到其上方的纸基片决定于该微流体体积和所加的RF信号功率。采用本方法实现了纸基NO2-浓度检测。

A new method of transporting micro-fluid in vertical direction is presented,which can make paper-based microflidic devices implement pretreatment operations of samples.Interdigital transducers（IDTs） and reflectors were fabricated on a 128° yx-LiNbO3 substrate using microelectric technlque,and a paper based microfluidic device was then placed on polydiomethylsiloxane（PDMS） blocks,which was mounted on the piezoelectric substrate.The space between the paper-based microfluidic device and the piezoelectric substrate was 2 mm.Two surface acoustic waves（SAWs） in opposite directions were excited when an amplified RF signal was applied to the IDTs.And then,the microfluid to be analyzed was transported vertically to the paper substrate by the SAWs.The transportation experiments were carried out using red dye solution micro-fluids with different volumes.The results show that the volume of microfluid and the RF power can affect the successful transportation of the microfluid from the piezoelectric substrate to paper substrate.The detection of NO-2 was also examined using the presented method.