Noble metal nanoparticles, due to their good physicochemical properties, have been exploited in biological applications. Among these metals, nanosilver has attracted great attention because of its optical properties and broad-spectrum antimicrobial activities with no drug tolerance.
The present study has attempted to conduct chemical synthesis of Fe 3O 4@PEG-Ag core/shell nanocomposites in aqueous solutions through co-precipitation of Fe 3+ and Fe 2+ ions, encapsulating the iron oxide core by poly (ethylene-glycol) (PEG) improve its hydrophilicity and biocompatibility, and immobilizing silver ions by application of NaBH 4 as a reducing agent.
The synthesized structures were characterized by Fourier-transform infrared (FT-IR), field emission scanning electron microscopy, energy-dispersive X-ray spectrum, wavelength-dispersive X-ray, vibrating sample magnetometer, inductively coupled plasma-mass spectrometry and transmission electron microscopy methods. Antimicrobial activity of the nanostructures against Staphylococcus aureus, Escherichia coli and Candida albicans was evaluated by broth microdilution based on the methods suggested by Clinical Laboratory Standard Institute. Furthermore, the nanocomposite was tested for possible anti-parasitic effects against Leishmania major promastigotes by MTT assay. Also, its impacts on bacterial cell morphology were defined using atomic force microscopy. Moreover, toxicity of the nanostructure related to animal cell line was determined based on MTT assay.