Laccase immobilized onto graphene oxide nanosheets and electrodeposited gold-cetyltrimethylammonium bromide complex to fabricate a novel catechol biosensor

In this study, a new biosensor is developed with reliable and easy-to-use biodevice properties for catechol determination in real samples. A method is proposed for the fabrication of biosensors to sense catechol based on the adsorption method of laccase immobilization. Hence, a glassy carbon electrode was modified via graphene oxide nanosheets and then it was modified with a gold-cetyltrimethylammonium bromide nanocomposite to adsorb and immobilize laccase on the electrode surface. The results showed laccase immobilization onto the reformed glassy carbon electrode, and a direct electron transfer reaction between laccase and the electrode. The mechanism of electron transferring was EC. Also, ks and were calculated as 0.41s-1 and 0.33, respectively. For this biosensor two linear ranges, 0.1x10-6 to 5x10-6 M and 16.7x10-6 to 166x10-6 M, and a detection limit of 1.5x10-6 M were obtained.