Unveiling biological activities of biosynthesized nanoscale Ag@Fe₂O₃/rGO nanocomposites

The bioinspired nanomaterials (NMs) are promising materials for biomedical applications because of their tunable, scaffold morphology, and biocompatibility properties. In particular, plant-mediated synthesis of NMs is widely preferred compared to other biological sources, viz. bacteria, fungi and algae due to its simplicity, eco-friendliness, sustainability, ease of operation, and safety in handling. The present study demonstrated the biosynthesis of Ag@Fe₂O₃ decorated reduced graphene oxide nanocomposites (Ag@Fe₂O₃/rGO NCs) employing leaves extract of Vachellia eburnea, serving as a natural reducing/stabilizing/capping agent. The fine structures of bioinspired Ag@Fe₂O₃/rGO NCs were confirmed at high temperature (900 °C), however, at low temperature viz. 350 °C, 500 °C, and 700 °C, the materials were associated with impurity. The biosynthesized NCs were systematically authenticated in terms of phase, crystallite size, structure, chemical state, and morphology using different spectroscopic techniques, including XRD, EDX, FTIR, Raman, XPS, FESEM, and HRTEM. Further, comparative biological activities such as antibacterial, antifungal, anti-inflammatory, anti-diabetic, and antioxidant were investigated using bioinspired NCs. The antimicrobial activity of biosynthesized NCs unveiled significant potential against E. coli (16 ± 0.25 mm) and C. parapsilosis (18 ± 0.30 mm), while molecular docking suggests multiple interactions with BSA (docking scores is − 10.76 kcal/mol). Further, the result unveiled at higher concentration, NCs shows significant inhibition (39.08 ± 0.42%) of BSA protein having IC₅₀ value of 53.94 µg/mL, whereas α-amylase inhibition activity found to be 50.80 ± 0.07% with IC₅₀ value 83.90 µg/mL. In addition, biosynthesized NCs exhibited superior antioxidant activity (88.38 ± 0.42%) with IC₅₀ value of 35.30 µg/mL.