UA-DMSPE Determination of Cu(II), Cd(II), and As(III) in Water, Soil, and Tomato Using a Novel Thiosemicarbazone Sorbent: ICP-OES Performance with DFT Characterization and Antimicrobial-Target Docking

Heavy metal pollution remains a critical global issue due to the toxic and bioaccumulative nature of elements, such as Cu-(II), Cd-(II), and As-(III). Their occurrence in water, soil, and food productsparticularly vegetablesposes serious ecological and health risks. In this work, a novel thiosemicarbazone (TSC) derivative was synthesized and structurally characterized, which has not been previously reported in the literature. The ligand was covalently immobilized onto a silica-based sorbent and applied in an ultrasound-assisted dispersive microsolid phase extraction (UA-DMSPE) protocol for the selective extraction and preconcentration of Cu-(II), Cd-(II), and As-(III). The method was validated on real samples, including irrigation water, agricultural soil, and tomato matrices collected from the Gediz River Basin (Türkiye), a region of intensive agricultural activity. Coupled with ICP-OES, the developed procedure provided high sensitivity, low detection limits, and reliable performance with minimal matrix effects. In addition, density functional theory (DFT) calculations were performed to probe the electronic features and reactivity of the ligand, while molecular docking studies explored its potential antimicrobial interactions. This integrated approach highlights the multifunctionality of the TSC ligand, offering both environmental monitoring capabilities and prospective biomedical applications. Overall, the proposed method demonstrates analytical robustness, environmental compatibility, and a strong potential for routine trace metal surveillance in complex matrices.