Design and application of a TiO2/clay/Ag hybrid nanocomposite for environmental remediation of cytotoxic pharmaceuticals

The contamination of water by cytostatic drugs poses a significant ecological risk. This study presents a novel TiO₂/clay/Ag catalyst, synthesized through a simplified sol-gel method, and applied for the efficient removal of etoposide (ETP) from aqueous environments. A thorough characterization of the catalyst's structural and morphological properties was carried out using various analytical techniques (XRD, FTIR, SEM, EDX, XPS). Several parameters, such as contact time, photocatalyst dosage, pH, and drug concentration, were studied. Under visible light irradiation, complete degradation (100%) of ETP molecules was achieved within 30 min. The degradation process followed pseudo-first-order kinetics. The catalyst's remarkable reusability is another key strength, as it showed excellent performance over five consecutive cycles, confirming its long-term applicability. In addition to its environmental sustainability and economic feasibility, this material demonstrated exceptional performance when applied to real environmental samples (surface water, incoming and outgoing wastewater). These findings suggest the catalyst's potential as a powerful, eco-friendly, and scalable approach to reducing pharmaceutical contamination in water.