Approaches Toward Allowing Electroanalytical Devices to be Used in Biological Fluids

Biofouling on surfaces can deleteriously affect the function of electrochemical sensor used in a biological fluid. The demand is thus to develop a sensor operatable in complex matrices. Herein, we concisely review the technologies developed to date to minimize fouling of electrochemical interfaces by blood-based fluids with an emphasis on affinity biosensing. The methods toward this sensor fabrication that are discussed here include approaches where; chemically modified surfaces with anti-fouling layers such as ethylene oxides, zwitterionics and some alternative antifouling agents; physical forces such as fluidic systems; electrode surface topography, prevent biofouling, as well as recent approaches where biofouling does not interfere with the response (aptasensors). Furthermore, the important emerging field of implantable biosensors, originated from such fabrication procedures is discussed.