Development of the electrochemical phenol biosensors

The aim of this study is to develop an enzyme-based amperometric phenol biosensor for phenol determination in wastewater. Firstly, screen printed electrodes (SPCE) were modified with electrochemical reduced graphene oxide (ERGO). The, polyneutral red films was prepared SPCE/ERGO electrodes by electropolymerization technique. Finally gold nanoparticles (AuNP) were formed on SPCE/ERGO/PNR electrodes by electrodeposition methods. Electrochemical characterization of each preparation step of the SPCE/ERGO/PNR/AuNP electrodes were performed by cyclic voltammetry (CV) methods. Immobilization of tyrosinase enzyme on SPCE/ERGO/PNR/AuNP electrodes was done with glutaraldehyde crosslinker. Optimum pH, optimum enzyme amount and optimum vorking potentiols of the prepared phenol biosensors were determined by amperometric method. Electrochemical characterization of the phenol biosensors was carried out under optimum conditions. The results of analytical characterizations, repeatability for 10 µM phenol, sensitivity, the limit of detection and the limit of quantification and the linear range were found to be 4.36% (n = 5) as relative standard deviation (R.S.D.), 0.326 µA. mM-1; 2.36 µA.mM-1 and 7.86 µA.mM-1 and was 5 µM - 150 µM respectively. The application of the prepared phenol amperometric biosensors was carried out fort he determination of phenol in wastewater.