Assessment of graphene oxide/MgAl oxide nanocomposite as a non-enzymatic sensor for electrochemical quantification of hydrogen peroxide

Abstract

Abstract Sensor technology demands to design a sensing system having higher sensitivity, sufficient selectivity, fast response time and efficient reproducibility with simple operating and recognition methodology. The chemical and biosensors with aforementioned features have been still challenging since several decades. Therefore we effectively designed graphene oxide nanocomposite based sensing system which exhibited remarkable electrocatalytic performance towards the recognition of key biomolecule, i.e., hydrogen peroxide (H 2 O 2 ) in a single step which reflects strong interaction between graphene oxide based nanocomposite and H 2 O 2 . Graphene oxide based nanocomposite was prepared by low cost and low temperature facile method and characterized by different spectroscopic techniques. The electrochemical sensing of as prepared nanocomposite towards H 2 O 2 was assessed using cyclic voltammetry (CV) and DC potential amperometry (DCPA at potential −0.570 V vs. Ag/AgCl reference electrode) in a phosphate buffer (pH = 7.0). The designed H 2 O 2 biosensor displayed high sensitivity (−0.2844 ± 0.0169 µA nM −1 cm −2 ), low detection limit (5 nM) with wide linear dynamic range (0.01–0.05 µM) and fast response time of less than 3 s. The performance of the sensor was optimized with various pH and different scan rates. Selectively, the biosensor recognized H 2 O 2 in the presence of glucose, uric acid and ascorbic acid, as interfering agent. Further evaluation of designed biosensor was made on commercially available cosmetic product with state of the art percent recovery value. Precisely, the designed biosensor would be a promising candidate for the electrochemical recognition and quantification of H 2 O 2 .