Chitosan for Biofunctionalization of Microsystems

We present the use of the polysaccharide chitosan for immobilizing biomolecules on microfabricated device surfaces. The main advantages of chitosan are its abundance of primary amine groups and its ability to be electrodeposited. Biomolecules are easily attached to chitosan 's amines by standard glutaraldehyde chemistry. The electrodeposition of chitosan allows accurate spatial and temporal control of biomolecule placement. We have demonstrated this biofunctionalization method for two different bioMEMS devices: a biophotonic sensor and a micromechanical biosensor. We have successfully assembled probe DNA on each of them and detected hybridization with target DNA as a demonstration of sensor operation. Here, we briefly present the fabrication procedure and testing results for both of these bioMEMS sensing devices