负压驱动蠕动微型泵的研究进展

基于负压驱动原理研制了一种结构简单的蠕动微型泵。微型泵由3层聚二甲基硅氧烷(PDMS)材料,构成气路层、驱动薄膜层和流路层,其全部结构均采用激光器加工制作而成,并通过表面等离子体氧化处理技术实现了各PDMS层之间的键合封装。该微型泵具有流速高、回流低、气泡耐受能力强,以及不伤害传送介质的特点。尤为重要的是,连接负压源的气路层通过PDMS薄膜能有效去除流路中的气泡,这是处理复杂流体样品时所期望的。通过对比前期微型泵的气路通道的流阻、常闭微阀的个数、负压压力和驱动频率等各项参数,获得了其性能参数。在50kPa负压和30Hz驱动频率的条件下,获得的最佳流速为600μL/min,这一流速参数可与正压气动型蠕动泵的流动性能相媲美。

Research Progress of a Peristaltic Micropump Driven by Pneumatic Pressure

Based on vacuum-driven principle,a simple peristaltic micropump is developed.The micropump fabricated by laser micromachining and plasma bonding of three polydimethylsiloxane(PDMS) layers,includes a pneumatic channel layer,actuation membrane layer,and microfluidic channel layer.The vacuum-driven peristaltic micropump offers high pumping rates,low backflow,appreciable tolerance to air bubbles,and minimal destruction to fluid contents.In addition,the pneumatic network with negative pressure provides a means to effectively remove air bubbles present in the microflow through the gas-permeable PDMS membrane,which can be highly desired in handling complex fluidic samples.Experimental characterization of the previous micropump performance has been conducted by controlling the resistance of the pneumatic network,the number of normally closed valves,the vacuum pressure,and the frequency of pressure pulses.A maximal flow rate of 600 μL/min has been optimized at the pulsed vacuum frequency of 30 Hz with a vacuum pressure of 50 kPa,which is comparable to that of compressed air-actuated peristaltic micropump.