Optoelectronic tweezers with patterned photoconductive layer for selecting, moving and storing particles and cells

In this work, we introduce a new type of optical micromanipulation platform that we call patterned optoelectronic tweezers (p-OET). In p-OET devices, the photoconductive layer (that is contiguous in a conventional OET device) is patterned, forming regions in which the electrode layer is locally exposed. We demonstrate that the micro-patterns in the photoconductive layer are useful for repelling unwanted particles/cells, and also for keeping selected particles/cells in place after turning off the light source. We propose that the new technique may be useful for myriad applications in the rapidly growing area of optical micromanipulation.