Abstract
A reagentless amperometric enzymatic biosensor is constructed on a carbon substrate for detection of ethanol. Yeast alcohol dehydrogenase
(YADH), an oxidoreductase, and its cofactor nicotinamide adenine dinucleotide (NAD+) are immobilized by adsorption and covalent attachment
to the carbon substrate. Carbon nanofibers grown by plasma enhanced chemical vapor deposition (PECVD) are chosen as the electrode material
due to their excellent structural and electrical properties. Electrochemical techniques are employed to test the functionality and performance of
the biosensor using reduced form of nicotinamide adenine dinucleotide (NADH) which also determines the oxidation peak potential of NADH.
Subsequently, amperometric measurements are conducted for detection of ethanol to determine the electrical current response due to the increase
in analyte concentration. The detection range, storage stability, reusability, and response time of the biosensor are also examined.