Electropolymerization of carboxymethyl-β-cyclodextrin based on co-electrodeposition gold nanoparticles electrode: electrocatalysis and nonenzymatic glucose sensing

A facile strategy is developed to fabricate an Au-CMCD/PCMCD electrode with high efficiency, universal, and selectivity electrocatalysis through electro-depositing carboxymethyl-beta-cyclodextrins with gold nanoparticles (Au-CMCD) followed by employing electro-polymerization carboxymethyl-beta-cyclodextrin (PCMCD). The chemical structure, microstructure, electrochemical activity, and electrocatalytic properties of Au-CMCD/PCMCD electrode are investigated. Due to the synergistic effect of the PCMCD and Au-CMCD layers, the as-prepared electrode exhibits an outstanding enhancement of universal electrocatalytic activity to eight kinds of crucial biomolecules and drugs, such as chloramphenicol, thymine, and glucose. Then, as a target analyte, glucose is used to investigate the sensing performances of Au-CMCD/PCMCD electrode. The amperometric detection of glucose shows a wide linear range expanding to 0.001 similar to 110 mM with a low detection limit of 0.99 mu M. More importantly, the absorption effect of PCMCD is stronger to glucose than other interfering species, which is favorable to avoid the influence of possible interfering substances. Furthermore, the glucose sensors reveal good stability and repeatability.