Microcantilevers (MCLs) hold a position as a cost-effective and highly sensitive sensor platform for
medical diagnostics, environmental, and fast throughput analysis. One of recently focus in this
technology is the development of biosensors based on the conformational change of proteins on
MCL surfaces. The surface stress changes due to conformational change of the proteins upon
interaction with specific analytes are promising as transducers of chemical information. We will
discuss our recent results on several biosensors due to conformational change of proteins. The
proteins include glucose oxidase (GOx), organophosphorus hydrolyses (OPH), Calmodulin (CaM),
and Horseradish peroxidase (HRP).
Recent terrorists events have shown that an urgent and widespread need exists for development of novel sensors for
chemical and biowarfare agents. The advent of inexpensive, mass-produced microcantilever sensors, promises to bring
about a revolution in detection of terrorists threats. Extremely sensitive chem/biosensors can be developed using
microcantilever platform. Both frequency and bending of microcantilevers can be used to detect the chemical and
biological species in air or solution. The specificity is achieved by immobilizing chemically-specific receptors the
cantilever. This short report will give an overview of chemical/biological warfare agents sensor recently developed
based on microcantilevers.
Layer-by-layer (LbL) nanoassembly in combination with traditional lithography and microfluidics was applied for the fabrication of ultrathin microcantilevers and for the modification of microchannel surface. Hundreds of cantilevers were fabricated on a silicon wafer simultaneously. The purpose is to develop chemical/biosensor arrays for parallel, massive data gathering. Microcantilever optical deflections were measured using a four-quadrant AFM head with integrated laser and position sensitive detector. In the second part, laminar flow fabrication of interpolyelectrolyte complexes was studied inside a microchannel. Polyelectrolyte micropatterns were studied using fluorescent confocal microscopy. Filament like, 15 μm, interpolyelectrolyte microstripes were formed at flow rate higher than 0.01 mL•min<sup>-1</sup> and concentrations of the initial polyelectrolytes below 1 mg•mL<sup>-1</sup>. New, soft micropatterning technique for the anisotropic modification of polyelectrolyte nanocapsules was also demonstrated. The microchannel surface was made sensitive to pH by coating the surface of the channel with a pH sensitive dye using LbL assembly to control the reaction.