In an antibody-based biosensor, the detection of the substance to be measured (an analyte) is brought about by its binding to an antibody. Antibodies are produced by the body in response to the invasion of a foreign substance known as an antigen, for example a virus or a bacteria. They have the characteristic of only binding to a single substance and nothing else. When combined with a sensor these antibodies can be used to quickly measure many substances like bacteria, viruses, drugs, hormones and many other chemicals. The analytes measured by our systems are being expanded to cover a much wider range, including the monitoring of female hormones levels for fertility tests, detection of environmental pollutants such as pesticides and biomedical substances such as warfare.

Composition of an antibody-based biosensor: (A) sample in environment; (B) a biological element, in this case the antibody, which forms a selective interaction with its corresponding antigen in (A); (C) a transducer which transforms the response from the interaction into an electrical signal; (D) an electronic component that is involved in data processing including the display (E).