Abstract

Biosensors are chemical sensors in which the recognition system utilizes a biochemical mechanism. The term biosensor has been variously used to a number of devices either used to monitor living system or incorporating biotic elements. The current consensus is that this term should be reserved for sensors incorporating a biological element such as an enzyme, antibody, nucleic acid, microorganism, or eukariotic cell where the biological element is in intimate contact with the transducer. The main purpose of the recognition system is to provide specificity to the biosensor, thus creating a device able to detect either a specific molecular target or a related family of compounds. The ability of biosensors to detect trace and low levels of biologically active substances is the main characteristic of these systems, and for this reason they have applications in the fields of medicine, biotechnology, food, and environmental science.