Unveiling the biomedical and photocatalytic properties of copper(II) imidazole complex-functionalized TiO2 nanoparticles

Abstract

The development of multifunctional nanoparticles (NPs) with enhanced biological and photocatalytic activities is crucial for biomedical and environmental applications. This study investigates the biomedical and photocatalytic potential of TiO₂ NPs grafted with a copper(II) imidazole complex, focusing on cytotoxicity, anti-inflammatory, antioxidant, and photocatalytic properties. The Cu-TiO₂ NPs exhibited significant biological and photocatalytic enhancements. Cytotoxicity assays on NSCLC cell lines revealed dose-dependent effects, with 47 % cytotoxicity at 300 µg/mL, increasing to 72 % at 500 µg/mL. Anti-inflammatory assessments via BSA denaturation assays showed 19 % inhibition at 100 µg/mL, rising to 78 % at 500 µg/mL, nearing cholecalciferol’s 84 %. The antioxidant capacity, measured through DPPH radical scavenging, demonstrated 42 % inhibition at 300 µg/mL and 68 % at 500 µg/mL, significantly surpassing the Cu(II) precursor complex but slightly below ascorbic acid’s 84 %. Photocatalytic degradation of Rhodamine B under UV irradiation achieved 86.4 % efficiency within 60 min, exceeding TiO₂ (45.4 %) and the RhB blank (14.7 %), with kinetic analysis confirming a pseudo-first-order reaction (k = 0.033 min⁻¹ for Cu-TiO₂ vs. 0.011 min⁻¹ for TiO₂). Phenol degradation tests further demonstrated 70 % removal efficiency, highlighting wastewater treatment potential. Notably, radical scavenger studies identified hydroxyl radicals (OH) as the primary reactive species, confirming the environmentally safe mechanism of photocatalysis. Importantly, the Cu-TiO₂ NPs have the added advantage of being biocompatible, making them a promising candidate for environmental remediation without negatively impacting living organisms. These findings underscore the significant cytotoxic, anti-inflammatory, antioxidant, and photocatalytic capabilities of Cu-TiO₂ nanoparticles, emphasizing their potential for cancer therapy, inflammation management, oxidative stress reduction, and environmental remediation, with future in vivo studies and mechanistic explorations essential to optimizing their therapeutic efficacy and photocatalytic performance.