Recent developments in electrochemical sensors based on graphene for bioanalytical applications

Abstract

An effective and affordable technique for detecting a variety of substances of biological, medical, and environmental significance is electrochemical sensing (ECS). Due to their distinctive structures and abilities to offer robust electrocatalytic activity with little surface fouling, low cost, biocompatibility, and simple electron transfer kinetics, carbon materials-based electrodes like graphene (GR) and carbon nanotube (CNT) are frequently used for the development of electrochemical sensors. Since GR has a large specific surface area, it can host a large number of biomolecules and still have a decent detection sensitivity. Along with important developments in the synthesis, purification, conjugation, and biofunctionalization of GR, device integration technologies and nanofabrication of GR have evolved. Combinations of the aforementioned characteristics have accelerated the development of GR-based sensors for many critical bio-analyses. Along with important developments in the synthesis, purification, conjugation, and biofunctionalization of GR, device integration technologies and nanofabrication of GR have evolved. The rapid development of GR-based sensors for many critical bioanalyses with better detection sensitivity and selectivity has been facilitated by the combination of the aforementioned features. Direct electron transport between the enzyme and the active electrode region is made possible by the application of GR. It is possible to easily construct and execute on-site sensors for oxidases and dehydrogenases with improved selectivity thanks to the excellent electro-catalytic activities of GR on the redox reaction of hydrogen peroxide (H₂O₂) and nicotinamide adenine dinucleotides (NADH).

Since GR's oxidation of NADH, thiols, H₂O₂, and other interfering species occurs at low potentials, the use of GR-based electrodes effectively suppresses these species. The two benefits of GR-based sensors for use in clinical chemistry, food quality and control, wastewater treatment, and bioprocessing are their great resistance to electrode fouling and selectivity.