Biosynthesis of pure hematite phase magnetic iron oxide nanoparticles using floral extracts of Callistemon viminalis (bottlebrush): their physical properties and novel biological applications

Abstract

Aqueous floral extracts of Callistemon viminalis were used to synthesize FeO nanoparticles (IONPs) which were intensively characterized through UV-vis, X-ray diffraction, HR-SEM/HR-TEM, Fourier- transform infrared spectroscopy (FTIR) and energy dispersive X-ray spectroscopy (EDS). Their physical properties were studied in response to different annealing temperatures. It was observed that the increase in the annealing temperature produced small-sized nanoparticles. The nanoparticle size was calculated as 32, 26 and 22 nm for annealing at 300, 400 and 500 °C, respectively. The magnetic nature of the bioinspired IONPs was revealed by superconducting quantum interference device (SQUID). Their antibacterial potential was investigated against nine pathogenic bacterial strains (gram positive and gram negative) using disc diffusion method while their MIC was calculated using broth dilution assay. Bioinspired IONPs were found to be highly effective against HepG2 cells (IC=20 µg/mL). Moderate antileishmanial activities against the promastigotes and amastigotes cultures are reported. Moderate acetylcholine esterase (AchE), butylcholine esterase (BchE) and α-Glycosidase inhibition are reported. Additional assessment of the biocompatibility was performed using haemolytic activity on the freshly isolated human red blood cells and macrophages. Furthermore, the antioxidant activities, including TAC, DPPH and TRP were also performed. Our results indicate that the biogenic and magnetic FeO can be used for diverse biomedical applications.

Biofabrication of iron oxide nanoparticles by leaf extract of Rhamnus virgata: Characterization and evaluation of cytotoxic, antimicrobial and antioxidant potentials

“…The IC 50 value calculated was 13.47 μg/ml. Our research work is also in agreement with previous work on biogenic IONPs conducted by Hassan et al The results are indicated in Figure (b).…”

“…No Bragg peaks for other related compounds were found, showing the pure‐crystalline nature of biogenic IONPs. The XRD pattern for IONPs is consistent with some earlier reports …”

“…Similarly, ALA against L . tropica amastigotes was shown by IONPs (IC 50 : 20.82 μg/ml), which is in agreement with earlier studies of biogenic IONPs nanoparticles . The dose‐dependent and lower IC 50 values of the IONPs showed that IONPs materials can be used for strong antileishmanial drug delivery in future medicines.…”

“…The green synthesis of IONPs was achieved according to the method used by Hassan et al with a few amendments. The aqueous leaves extract was obtained by adding 10 g of cleaned leaves powder into 250 ml of double‐distilled H 2 O, and was heated at 80°C on a hot plate under continuous stirring for 2 hr.…”

“…Although numerous metals exist in nature, only a few of them such as iron, silver, gold, tin and platinum are synthesized extensively in nanostructured form . Among these metals, iron oxide (IO)NPs have potentially gained the attention of the scientific community due to their unique properties and potential applications in biomedicine, diagnostics, therapeutics, bioremediation, cosmetics and materials engineering . Currently, IONPs have been used in the controlled release of drugs in tissue repairing, diagnosis and treatment of solid tumors through magnetic resonance imaging .…”