A biosensor is an analytical device that combines a biological component with a physicochemical detector to detect a chemical substance. The device consists of a biological sensing element and a transducer, which converts the data into electrical signals. The biological element, also known as the bioreceptor, uses biomolecules from organisms or receptors modeled after biological systems to interact with the analyte of interest. The interaction is measured by the biotransducer, which outputs a measurable signal proportional to the presence of the target analyte in the sample. A biosensor typically consists of a bio-receptor (enzyme/antibody/cell/nucleic acid/aptamer), transducer component (semi-conducting material/nanomaterial), and electronic system which includes a signal amplifier, processor & display. The general aim of the design of a biosensor is to enable quick, convenient testing at the point of concern or care where the sample was procured.
There are many potential applications of biosensors of various types. The main requirements for a biosensor approach to be valuable in terms of research and commercial applications are the identification of a target molecule, availability of a suitable biological recognition element, and the potential for disposable portable detection systems to be preferred to sensitive laboratory-based techniques in some situations. Some examples of biosensors are:
- Biological biosensors, also known as bioanalytical sensors, which use living cells or tissues as the sensing element.
- Enzyme biosensors, which use enzymes as the sensing element.
- Immunosensors, which use antibodies as the sensing element.
- DNA biosensors, which use DNA as the sensing element.
- Optical biosensors, which use optical fibers to detect sensing elements based on the different properties of light like absorption, scattering, and fluorescence.
Biosensors have many potential applications in various fields, including medical diagnosis, environmental monitoring, food safety, and biodefense.
