Tóm tắt

A new enzyme-electrode is developed for the determination of ethanol by immobilizing carboxylatedrngraphene (CG) and alcohol oxidase (AOX) on poly diallyldimethylammonium chloride (PDDA) modifiedrngraphite electrode (Gr). The biosensor showed high sensitivity and rapid detection of ethanol in the con-centration range 250lM to 1500lM. Addition of ethanol reduced the reduction current of oxygen, whichrnis due to the consumption of molecular oxygen for the oxidation of ethanol. The effect of temperature andrnpH on the performance of the biosensor has been studied. The excellent performance of the biosensor isrnattributed to large surface to volume ratio and high conductivity of graphene. This promotes direct elec-tron transfer between redox enzymes and electrode surface. Low operating potential and specificity ofrnthe enzyme will restrict the interference of ascorbic acid, acetaminophen, and glucose. The biosensorrnwas characterized by field emission scanning electron microscopy (FESEM) and cyclic voltammetryrn(CV) using Fern2+rn/Fern3+rnas an electrochemical probe