Protective membranes at electrochemical biosensors

The primary role of the biosensor is to specifi cally detect an analyte using biochemical reaction or interaction mediated by isolated biomolecules, organelles, whole cells or biomimetic receptors. In terms of construction and function, the biosensor consists of biorecognition element and transducer connected to suitable measurement device. Electrochemical biosensor is an electrode or microelectrode with the surface chemically modifi ed by the biorecognition element. The main problem of analysis with the biosensors is the presence of low and high molecular weight substances in the sample that interfere at the detection of analyte. Due to deposition of surface active compounds the biosensor response may be diminished depending on time of interaction with sample. These effects can be eliminated by using anti-interference membranes. This review deals with preparation and utilization of membranes for the biocomponent immobilization and with outer-sphere protective membranes.