Matrix Addressing of an Electronic Surface Switch Based on a Conjugated Polyelectrolyte for Cell Sorting

Spatial control of cell detachment is potentially of great interest when selecting cells for clonal expansion and in order to obtain a homogeneous starting population of cells aimed for tissue engineering purposes. Here, selective detachment and cell sorting of human primary keratinocytes and fibroblasts is achieved using thin films of a conjugated polymer. Upon electrochemical oxidation, the polymer film swells, cracks, and finally detaches taking cells cultured on top along with it. The polymer can be patterned using standard photolithography to fabricate a cross‐point matrix with polymer pixels that can be individually addressed and thus detached. Detachment occurs above a well‐defined threshold of +0.7 V versus Ag/AgCl, allowing the use of a relatively simple and easily manufactured passive matrix‐addressing configuration, based on a resistor network, to control the cell‐sorting device. Selective and electronically controlled cell detachment is achieved using a conjugated polymer that detaches when electrochemically oxidized. The polymer is patterned to create a matrix with individually addressable pixels. The addressing is based on passive matrix addressing and is controlled by a resistance network. Human skin cells are cultured on the matrix, show good viability, and can be selectively detached.