Fabrication inside microchannels using fluid flow

This Account summarizes techniques for carrying out microfabrication of str uctures with dimensions down to 10 mum in microchannels that are 0.02-2 mm wide. These methods are largely based on the exploitation of laminar flow a t low Reynolds number (Re) to control the spatial delivery of reagents. The se methods are illustrated by fabrication of fibers, microelectrode arrays, arrays of crystals, and patterns of proteins and cells.