| The technique for microfluidic handling is the most important part of μTAS, and the development of the micropumps that adjust micro-scale channel is the basis of achieving microfluidic handling. Currently, different types of micropumps were developed.Based on the literatures about the study of micropumps in uTAS for these years, this thesis brought forward a novel approach for microfabrication of modified pneumatic microvalves on microfluidic chips using glass-PDMS bonding technique. And then we studied on the factors that may influence the capability of microvalves.Next, it was further to integrated several pneumatic valves into one compound chip to fabricate a peristaltic micropump. And a Visual Basic parallel port control program was used to drive electromagnetical valves through an amplifying circuit. Thus, the switch of gas channels in pneumatic micropump can be controlled.The results obtained indicate that the operating reliability of the micropumps and microvalves has been improved by using the AZ 4620 photoresist to make the molds of fluid channel. Due to the pneumatic microvalves and micropumps with compound microchip device, the difficulty of chip processed and cost of stuff was reduced, and its rigidity intension was greatly enhanced at the same time. Besides, the credibility of connection between microchip and external connected channels was increased. The output pressure of the peristaltic pneumatic micropump is up to 155cmH2O, and the output flow rate is up to 1.6 μL/min. The output pressure and flow rate of the micropump were influenced by working frequency, width of the fluid channel, manifold pressure and thickness of the PDMS membrane.The modification of pneumatic microvalves and the manufacture of pneumatic micropumps on glass—PDMS microfluidic chips created the condition for application of the pneumatic microvalves and micropumps, such as the construction of the flow injection analytical system on microfluidic chip, etc. .
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