The Preparation, Morphological Characterization and Possible Electroanalytical Application of a Hydroxyapatite-Modified Glassy Carbon Electrode

Abstract

By simple modification of a GC electrode with biofunctional material, hydroxyapatite (HAp), an efficient electroanalytical tool, was designed and constructed. Modification of the GC surface includes two steps in synthesis: electrochemical deposition and chemical conversion. The properties, structure, and morphology of a nanosized material formed on a surface and absorbability were studied by electrochemical impedance spectroscopy, Fourier-transform infrared spectroscopy and scanning electron microscopy with energy-dispersive spectroscopy analysis. Numerous methods in this work confirmed that the developed method for controlled HAp deposition results in a HAp open structure and uniform morphology, which is capable of the selective absorption of the target species. The main goal of this study was the possibility of using a HAp-modified electrode for the fast screening of copper, cadmium, and lead content in honey and sugar samples. The electrochemical behavior and potential of the electroanalytical determination of heavy metals using the HAp/GC electrode were studied using cyclic voltammetry and square wave anodic stripping voltammetry. The HAp/GC electrode exhibited great performance in the determination of heavy metals, based on the reduction of target metals, because of the high absorbability of the HAp film and the electroanalytical properties of GC. A linear response between 10 and 1000 μg/L for Cu and Pb and 1 and 100 μg/L for Cd, with an estimated detection limit of 2.0, 10.0, and 0.9 μg/L, respectively, was obtained.