Biochemical Modulation of Fe₂O₃/CuFe₂O₄ Nanocomposite via Two-Stage Calcination: Antimicrobial Efficacy and In Vivo...

Fe₂O₃/CuFe₂O₄ nanocomposite fabricated by a two-stage calcination process. X-ray diffraction established that α-Fe₂O₃ is the predominant phase, accompanied by little CuFe₂O₄ spinel, with no extraneous impurity phases identified. In vitro bioassays exhibited robust broad-spectrum antibacterial efficacy of the nanocomposites. Agar-diffusion assays demonstrated that sample BB2 (300°C and 300°C) yielded the most substantial inhibitory zones against Salmonella typhimurium (22.0 ± 0.5 mm) and Staphylococcus aureus (22.0 ± 0.3 mm), far surpassing antibiotic controls (11-14 mm). Significantly, only BB3 and BB4 demonstrated inhibitory effects on Candida albicans (zones 14.0-18.0 mm). MIC/MBC assays validated these trends: BB4 demonstrated the lowest MIC/MBC (25/50 µg/mL) against both S. typhimurium and S. aureus, whereas BB2/3/4 inhibited C. albicans at 25/50 µg/mL. All samples significantly impaired biofilm formation (50%-82% decrease), with BB2 achieving around 80% suppression across all pathogens. The results demonstrate that the two-stage calcined Fe-Cu mixed oxide successfully eliminates both Gram-positive and Gram-negative bacteria, as well as fungi. In vivo toxicological assessment revealed no notable deleterious effects on hepatic function, indicating preliminary hepatic tolerability. The optimized Fe₂O₃/CuFe₂O₄ nanocomposite has significant multi-modal antibacterial effectiveness and minimal acute toxicity, underscoring its potential for innovative infection-control applications.