A biological material sensing surface is exposed to a biological material that is selectively bound to a selected sensing portion of the sensing surface. The sensing surface is then subjected to shear stress oscillations to selectively remove nonspecifically bound material. The shear stress may be provided by an ultrasound resonator operating at a power sufficient to selectively remove nonspecifically bound biological material, such as protein from non-sensing areas of the sensing surface, which may be micropatterned array.
 The invention described herein was made with U.S. Government support under Grant Number MDA-972-00-1-0021 awarded by DARPA. The United States Government has certain rights in the invention.
 Use may have been made of the Sandia laboratory. Sandia is a multi-program laboratory operated by Sandia Corporation, a Lockheed Martin Company, for the United States Department of Energy's National Nuclear Security Administration under contract DEAC0494AL85000.