Development of biosensors for immunoassays.

Biosensors represent a new generation of analytical instruments incorporating a biological sensing element in contact with a physical transducer and an output device. The biological element may be a whole organism, an organelle, an enzyme, an antibody, cell receptors or nucleic acids. The transducer converts the interaction between the biological component and the sample into a measurable signal which could be an electrical charge, an optical signal, a heat exchanger or some other quantifiable event. In recent years, electrochemical sensors based on continuous potentiometric or amperometric detection of enzyme reaction products have been favoured in the development of biosensors. This is because electrochemical transducers are cheap, rapid to use and portable.