Spectrophotometric Determination of Copper(II) Ions: Method Development and Analytical Validation

Abstract

This study presents the development and analytical validation of a simple, cost-effective, and reliable spectrophotometric method for the quantitative determination of Copper(II) ions in aqueous solutions. The method is based on the formation of a colored complex between Copper(II) ions and a selective chromogenic reagent under optimized reaction conditions, exhibiting maximum absorbance at a specific wavelength. Critical parameters including pH, reagent concentration, reaction time, and stability of the complex were systematically optimized to enhance sensitivity and selectivity. The proposed method demonstrated excellent linearity over a broad concentration range, with high precision (RSD < 2%), accuracy (recovery between 98%–102%), and a low detection limit suitable for trace analysis. Interference studies revealed minimal interference from common ions, affirming the method's applicability to real samples such as tap water, industrial effluents, and biological fluids. Method validation was performed according to ICH guidelines, confirming its robustness and reproducibility. This validated spectrophotometric approach offers a valuable tool for routine monitoring of Copper(II) ions in environmental and industrial laboratories.