SENSORS

Electrochemical sensors can monitor target analytes online, eliminating chain-of-custody concerns associated with off-line analysis. These sensors are small, rugged and often extremely selective. Guelph scientists are working in several programs to develop new electrochemical sensors.

Metal Oxides

Development of gas sensors is important not only for air pollution control but for improving the efficiency of automobile engines. Metal oxides have found application because their large band gap makes undoped materials highly resistive. Consequently, their conductivity is highly sensitive to the number and nature of adsorbed gas molecules on the surface and at grain boundaries. For effective sensing, the metal oxide must be porous. Centre researchers are studying a variety of metal oxide films that are highly resistive and porous. They plan to develop new preparation methods and design new oxides that will be more sensitive and selective.

Biosensors

Researchers produce biosensors and chemical sensors by attaching thin organic films to conductive electrodes. They make these films respond selectively to particular species through molecular engineering, by incorporating either specifically designed or biological catalytic reagents, such as enzymes or antibodies. These thin organic films are designed for many functions. For example, one component of the membrane excludes interfering species, while another may serve to bind or concentrate the analyte before its detection.