Molecularly Imprinted Voltammetric Sensor Based on Chitosan-CNTs Decorated with AuNPs Nanocomposite for Catechol Detection

Abstract

This research is based on the development of a novel, biocompatible and sensitive electrochemical imprinted sensor based on the detection of a phenolic compound, such as catechol, employing electroactive nanomaterials with the objective of improving the electron transfer between the electrode surface and the solution [1] and a natural biopolymer due to its excellent layer forming ability [2]. The development of the sensor is based on the modification of multiwalled carbon nanotubes (MWCNTs) with gold nanoparticles (AuNPs). The decorated MWCNTs have been recovered with a polymeric chitosan (CS) matrix generating a nanocomposite that contains the electroactive material inside. The polymeric matrix of CS that holds the modified MWCNTs has been electrodeposited in the presence of the phenolic compound on a boron doped diamond (BDD) electrode. The sensor surface has been structurally characterized to demonstrate the correct adsorption of the film and the correct recovery of the decorated carbon nanotubes on the BDD electrode surface. The performance as an electrochemical MIP sensor analyzed by cyclic voltammetry has offered excellent characteristics, demonstrating a high affinity to catechol with high selectivity, reproducibility, repeatability and sensitivity in the range of catechol concentrations from 0 to 1 mM. Finally, the implementation of the sensor to measure in a complex red wine sample has been carried out. The obtained results have resulted to be successful to quantify catechol in the real matrix. For these reasons, the proposed research manifests a promising and interesting way to implement an imprinting biocompatible polymers method in the development of an electrochemical sensor for phenols detection in the 4.0 industry.[1] S. A. Zaidi, Sensors Actuators B. Chem., 2018, 265,488-497.[2] A. Gopalan, S. Komathi, N. Muthuchamy, K. Lee, M. J. Whitcombe, L. Dhana, y G. Sai-anand, Prog. Polym. Sci., 2019 88, 1-129. Acknowledgments: Financial support by MINECO and FEDER (RTI2018-097990-B-100 and BES-2016-077825) and the Junta de Castilla y León-FEDER (VA-275P18) is gratefully acknowledged.