In this paper, a new type of microfluidic pump that can be activated and controlled by a masked light source is presented. The actuation of this micropump is based on an optopiezoelectric composite. This composite is constructed by having one of the electrodes of a piezoelectric PVDF (polyvinylidene fluoride) polymer replaced by a layer of TiOPc (titanyl phthalocyanine) photoconductive coating and an ITO (indium-tin-oxide) transparent electrode. This layer of photoconductive electrode provides the capability to activate multiple locations of this optopiezoelectric composite independently using a masked light source and a single voltage source. To verify the feasibility of this concept, dual light-activated microfluidic pumps based on this optopiezoelectric composite are implemented and studied. Experimental results verify that two microfluidic pumps can be created by one optopiezoelectric composite and that each pump can be optically turned on and off independently or be turned on simultaneously. These results suggest that integrating an optopiezoelectric composite into a lab-on-a-chip system can reduce the size and the number of driving units significantly, since every operation can be done optically and only one driving source is needed. The equivalent circuit, design, and implementation of dual light-activated optopiezoelectric micropumps are discussed in this paper.

In this paper, we present a new type of piezoelectric composite material, optopiezoelectric thin-film, to serve as a lightactivated micropump for integrating with a microfluidic device. By using a photoconductive material (titanium oxide phthalocyanine) to serve as one of the electrodes of a piezoelectric polyvinylidene fluoride (PVDF) polymer, multiple locations of this optopiezoelectric thin-film can be actuated independently with one driving voltage source and a programmable light mask. Integrating this optopiezoelectric thin-film to a microfluidic device, complex operations of a multi-functioned microfluidic device can potentially be simplified and scaled up. Here, we present our preliminary result to demonstrate the feasibility of using one optopiezoelectric thin-film to serve as two microfluidic micropumps controlled by a light mask.

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