A novel thermal biosensor: evaluation for determination of urea in serum Original Research Article

A novel thermal biosensor has been made based on heat conduction through a BiTe-thermocouple on alumina plates. The sensing element was in close thermal contact with a gold tube enzyme reactor in a flow injection system. It was successfully applied to bovine serum samples where urea could be determined from a calibration graph or by standard addition. The linear range of the system was 0.5–15 mM with a detection limit of 0.5 mM. A throughput of up to 60 samples per hour was achieved.