Design, construction, and testing of a compact USB powered potentiostat for biosensor applications

This thesis investigates the design, construction and testing of a compact potentiostat for an aptamer-based biosensor, suitable for point-of-care testing (POCT) applications. A potentiostat applies a pre-programmed time varying voltage to a set of electrodes that hold a biomolecular sample, and simultaneously monitors the resulting electrochemical signals. The potentiostat is designed to operate and communicate through a standard USB port of any computer. The sensor platform is composed of a 3-electrode system and constructed using microfabrication techniques; in conjunction with the potentiostat the device performs cyclic voltammetric tests on surface-bound, redox-labelled biomolecular samples. The performance of the system is compared to that of a commercial benchtop potentiostat. Results of this research will contribute to the design of a stand-alone, USB powered, biomolecule detection system. Such a system may in turn form the basis of future hand-held, ultra-compact, point-of-care biosensors for disease screening and personal health care monitoring.