Fe2O3-type iron oxide nanoparticles from Aerva lanata leaf extract exhibit antibiofilm, discriminatory toxicity in cancer cells, and theranostic against oxidative stress in zebrafish

In the study, phytosynthesized iron oxide nanoparticles (Fe NPs) from Aerva lanata leaf extract. The phytosynthesized Fe NPs were characterized and assessed for multi-biofunctional features such as antioxidant, antibiofilm, and theranostic against oxidative stress in zebrafish embryos. UV–vis spectroscopy confirmed the phytosynthesis of Fe NPs and found λ_max 390 nm. Fourier transform infrared spectroscopy (FTIR) revealed the role of A. lanata leaf extract in the synthesis of Fe NPs. Fe NPs exhibited crystalline in nature, stable (-27 mV zeta potential), and 91.8 d.nm. X-ray crystallography (XRD) revealed that Fe NPs were crystalline with a 26 nm size. The EC₅₀ value (concentration required to scavenge 50 % of free radicals) of Fe NPs in ABTS and DPPH assay was 76.21 ± 1.39 and 81.53 ± 3.07 µg/mL, respectively. Fe NPs exhibited potential antibacterial activity against B. subtilis, E. coli, K. pneumoniae, and S. aureus by micro-well dilution technique. Fe NPs exhibited a dose-dependent effect on biofilm damage and reactive oxygen species (ROS)-mediated oxidative stress in bacteria. The live/dead assay revealed that Fe NPs-induced bacterial death by compromising the membrane integrity. The MTT cell viability assay and morphological observations revealed that Fe NPs discriminatorily induced cytotoxicity in MDA-MB-231 cancer cells (human breast cancer cell line) related to HEK-293 normal cells (human embryonic kidney cells). The IC₅₀ value of Fe NPs (concentration required to reduce 50 % of cell viability) against MDA-MB-231 and HEK-293 cells was observed as 158.29 ± 4.78 and 187.08 ± 5.64 µg/mL, respectively. Fe NPs highly escalated the ROS and caspase-3 levels in cancer cells related to normal cells. Fe NPs were highly selective in inducing oxidative-stress-mediated apoptosis in cancer cells. Moreover, this is the first report to reveal the unique theranostic potential of A. lanata leaf extract-mediated synthesized Fe NPs against oxidative stress. Fe NPs were found biocompatible up to 50 µg/mL in zebrafish embryos at 24, 48, 72, and 96 h post fertilization (hpf). Moreover, Fe NPs showed amelioration potential against hydrogen peroxide-induced oxidative stress at 30 µg/mL. Thus, phytogenic Fe NPs could be useful to reduce the biofilm formation of multidrug-resistant bacteria, a major problem today. Moreover, phytogenic Fe NPs are highly helpful in overcoming oxidative stress-mediated disorders like cancer, neurodegenerative, diabetes, inflammation, cardiovascular diseases, etc.