Ultrasonication and electrochemically-assisted synthesis of reduced graphene oxide nanosheets for electrochemical sensor applications

Development of electrochemical sensors requires a facile fabrication method using advanced electrode materials. Herein, electrochemically reduced graphene oxide was synthesized assisted by ultrasonication in order to modify the electrode surface. The method was applied for the electrochemical investigations of ambroxol drug using linear, cyclic, and square wave voltammetric techniques in the presence of sodium coco-sulphate. It was found that the nascent electrode showed slower performance compared to the modified electrode, suggesting its increased sensitivity in the presence of sodium coco-sulphate. Investigations were performed to understand the reliability of the peak current and peak potential at different pH values (3.0–11.2 pH) of the supporting electrolyte. The electro-oxidation of ambroxol was observed to be adsorption controlled. Square wave voltammetry showed the lowest detection limit of 2.5 nM, lower than those results reported in the literature for the drug offering good retrieval data from human urine and pharmaceutical samples, suggesting potentiality of the fabricated sensor in clinical and quality control applications.