A Novel, Rapidly-Constructed Synergistic Copolymer-Metallocene Electrode with Drug-Detection Capabilities

Electropolymerized poly(diphenylamine-co-4,4 '-diaminodiphenyl ether) (P(DPA-co-4,4 '-DADPE)) on carbon paste electrode (CPE) surface, forms a thin, porous nanofilm with low impurity content, and high resistance to toxicity and electrocatalytic properties. In this research, we aim to enhance the properties of the copolymer by immersing it in a chloroferrocene solution for only 4 min. This facilitates the formation of a novel, robust synergistic electrode. Optimization of this electrode is influenced by the concentration of ferrocene, immersion time, and scan rate. Various characterization techniques including CV (Cyclic Voltammetry), FESEM (FieldEmission Scanning Electron Microscopy), EDS (Energy-Dispersive X-ray Spectroscopy), XRD (X-ray Diffraction), and IR (Infrared Spectroscopy) were employed to investigate the electrode. This synergistic electrode exhibits a current density of 9.67 and 24.67 times higher compared to nano-copolymer and ferrocene electrodes, respectively. The kinetic parameters, Gamma*, alpha, ks, and n, for the electrode, are 4.10 x 10- 7 mol/cm2, 0.485, 61.13 s- 1, and 1. As a result, the electrode displays appropriate velocity, quasi-reversible kinetic characteristics, and behavior compatible with the surface adsorption process. Furthermore, it exhibits a higher active surface concentration of redox compared to copolymer and ferrocene electrodes. The synergistic electrode also demonstrates a significant improvement in electron exchange yield with Delta Ep, 43 % less than copolymer/CPE. These findings, combined with electrochemical stability and pH independence of the new electrode, resulting from the synergistic effect of ferrocene and copolymer, indicate its potential as a robust redox mediator. Finally, the catalytic effect of the electrode in cyclic voltammetry detection of amoxicillin was confirmed, with a Limit of Detection (LOD) and Limit of Quantification (LOQ) within the dynamic range of 2.00 x 10- 5-8.00 x 10-4 M, was estimated to be equal to 1.42 x 10-6 and 4.73 x 10-6, respectively.