Development of biocompatible micropatterns for single-cell biosensors

A standard semiconductor process and a chemical immobilization of the functional groups to the glass surface were used to fabricate the biocompatible base substrates for the cell biosensor with specific micropatterns of amine groups and, thereby to create the extracellular protein island of the defined shape and size that support a single cell attachment. Defined size, 15 - 100 micrometer in each side, of rectangular pattern was obtained by the bulk- etching of n-type [100] Si wafer. After etching process of glass with concentrated HNO3, the glass substrate covered with the silicon mask was exposed to hexamethyldisilane vapor at 200 degrees Celsius for 30 minutes to couple the silane. Human umbilical vein endothelial cells were cultured on the micropattern after crosslinking the human fibronectin to micropatterned silane. It was possible to adhere endothelial cells in a predetermined location and shape with this technique. The responsibility of adhered endothelial cells to physical stress, such as blood flow, was limited by the controlling the polymerization of actin cytoskeleton and morphology of the cell. The simple laminar flow chamber was developed to exposure defined laminar shear stress on the micropatterned endothelial cell array. Fabrication of biocompatible micropattern with this method is experimentally simple and highly reproducible for application of the cell biosensor for physical and chemical applications.