ABSTRACT
Initial applications focused on the determination of glucose and urea; subsequently the enzyme thermistor devices have been applied in the determination of a wide variety of molecules. The enzyme thermistor assay is normally performed by a flow injection technique. The sample pulses employed are too small to give a thermal steady state but result in a temperature peak that can be registered by a recorder. A very promising development of miniaturized thermal biosensor devices is in progress, which further increases the potential in biomedical applications. Thermistors are resistors with a very high negative temperature coefficient of resistance. A relatively sensitive determination of cholinesterase inhibitors has been made using butyrylcholine as substrate. Enzyme thermistor assays for a large number of different metabolites have been proposed. Consequently many enzyme thermistors are used in industrial laboratories for penicillin analysis. Fresh enzyme can then be immobilized on the column simply by injecting the enzyme preparation while the column remains in the enzyme thermistor apparatus.
