Functionalization of niobium nitrogen-doped titanium dioxide (TiO₂) nanoparticles by using Mucuna pruriens methanolic extracts

Titanium dioxide nanoparticles (TiO₂ NPs) have garnered considerable attention due to their diverse applications. Introducing niobium (Nb) and nitrogen (N) doping, followed by functionalization with Mucuna pruriens beans methanolic extracts, offers a novel avenue to harness their antioxidant potential. This functionalization enables Nb-N doped TiO₂ NPs to engage with the bioactive compounds inherent to M. pruriens beans methanolic extracts, thereby fostering a synergistic enhancement of antioxidant activity. This study focuses on the functionalization of doped Nb-N-TiO₂ NPs and evaluates the antioxidative capabilities of those functionalized NPs to pure doped Nb-N-TiO₂ NPs. These functionalized NPs (FNb-N-TiO₂) underwent characterization through ultraviolet–visible spectroscopy (UV–Vis), Fourier Transform Infrared Spectroscopy (FTIR), and Scanning electron microscopy (SEM) analysis. Subsequently, their antioxidant capabilities were evaluated using 2,2-diphenyl-1-picrylhydrazyl (DPPH) and Ferric Reducing Antioxidant Power Assay (FRAP) assays. Functionalized Nb-N-TiO₂ NPs FTIR peaks exhibited at 2430 and 2010 cm⁻¹; unrelated peak vibrations are associated with the (Nb-N) doping, and the increased transmittance signifies successful functionalization and potential bonding between M. pruriens extract phytochemicals. A distinctive triangular aggregation pattern in SEM ranging in size from 5 µm to 500 nm was seen in FNb-N-TiO₂. At a concentration of 500 μL⁻¹, FNb-N-TiO₂ exhibited exceptionally high antioxidant activity, reaching an impressive 70% compared with pure Nb-N-TiO₂ NPs at 51%. The results demonstrated that FNb-N-TiO₂ NPs exhibit significant antioxidant properties compared to their non-functionalized, pure Nb-N-TiO₂ NPs. In conclusion, this study substantiates the considerable antioxidant potential of doped Nb-N-TiO₂ NPs mediated by M. pruriens methanolic extract, thereby emphasizing their potential for diverse applications in both biomedical and environmental sciences.