Principles of Affinity-Based Biosensors

The use of antibodies as recognition elements in bioanalytical assays can be traced back to the late 1950s. Yalow and Berson (1 ) pioneered radioimmunoassay for measurement of insulin and in the followmg year Ekins (2 ) used this technique to measure thyroxine. Reports involving the use of antibodies in devices that might now be referred to as biosensors began to emerge in the early 1970s with the work of Kronick and Little (3 ), Glaever (4 ) and Tromberg et al. (5 ). In the past decade, a wide variety of affinity-based biosensor contigurations have been reported. Current consensus opinion would suggest that affinity-based biosensors are analytical devices that use an antibody, sequence of DNA, or receptor protein interfaced to a signal transducer to measure a binding event.