Development in Heavy Metal Ions Detection: Antimony-Hydroxyapatite Modified Electrodes Coupled with Square Wave Anodic Stripping Voltammetry

The occurrence of heavy metal ions in environmental matrices presents serious risks to human health and ecosystems. An electrochemical sensor for the simultaneous detection of lead (Pb) and cadmium (Cd) ions in aqueous samples is presented in this study. The sensor was optimized through material composition, electrolyte, deposition, and electrochemical parameters using a modified carbon paste electrode (CPE) comprising hydroxyapatite (HAp) and antimony (Sb). Calibration studies showed high sensitivity (0.574 ± 0.32 ppb) and strong linearity (R2 = 0.993) for Pb detection. Repeated studies showed that the minimum standard deviation (RSD) was ±3.73%, confirming the reliability of the results. Real sample analysis of tap water with the developed method had less than 5% deviation in results as compared to results obtained from atomic absorption spectrometry (AAS). Furthermore, promising results were obtained from simultaneous detection of Pb(II) and Cd(II) ions, thus the sensor showed reliability for practical applications.