Evaluation of electrospun poly (vinyl alcohol)-based nanofiber mats incorporated with Zataria multiflora essential oil as potential wound dressing.

Infections, especially those caused by multi-drug resistant pathogens, result in serious problems in wound healing process. In this study, Zataria multiflora (ZM) essential oil, as a strong natural antimicrobial agent, is incorporated into poly (vinyl alcohol)-based nanofiber mats to fabricate a novel wound dressing. Different amounts of ZM essential oil (0, 2, 5 and 10% (v/v)) were incorporated into chitosan/poly(vinyl alcohol)/gelatin (CS/PVA/Gel) solutions and then were successfully electrospun into beadless and uniform fibers with 95 ±â€¯14, 154 ±â€¯27, 187 ±â€¯40 and 218 ±â€¯58 nm in diameters, respectively. The produced nanofiber mats (CS/PVA/Gel/ZM) were chemically crosslinked by glutaraldehyde vapor. The chemical compositions of ZM essential oil and nanofiber mats were analyzed using Gas Chromatography-Mass Spectrometry (GC-MS) and Fourier Transform Infrared Spectroscopy (FTIR), respectively. The antimicrobial activity of the CS/PVA/Gel/ZM nanofiber mats was determined by the AATCC100 method. The nanofiber mat loaded with 10% of ZM essential oil completely inhibited the growth of Staphylococcus aureus, Pseudomonas aeruginosa and Candida albicans after 24 h of incubation. Swelling investigations showed that the produced nanofibers have a substantial ability to take up water, in the range of 400-900%. Mechanical properties of the nanofiber mats were studied by tensile testing. Furthermore, they were found to be non-toxic by biocompatibility assays on mouse fibroblast (L929) cells. The obtained results have demonstrated that CS/PVA/Gel nanofiber mats, loaded with ZM essential oil, are promising alternatives to conventional wound dressings.

Modified magnetic nanoparticles by PEG-400-immobilized Ag nanoparticles (Fe3O4@PEG-Ag) as a core/shell nanocomposite and evaluation of its antimicrobial activity.

BACKGROUND: 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. PURPOSE: The present study has attempted to conduct chemical synthesis of Fe3O4@PEG-Ag core/shell nanocomposites in aqueous solutions through co-precipitation of Fe3+ and Fe2+ ions, encapsulating the iron oxide core by poly (ethylene-glycol) (PEG) improve its hydrophilicity and biocompatibility, and immobilizing silver ions by application of NaBH4 as a reducing agent. PATIENTS AND METHODS: 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. RESULTS: In general, the synthesized core/shell nanostructure can demonstrate noticeable activity against the evaluated representative microorganisms while its toxicity against animal cell line is not considerable. CONCLUSION: This nanostructure can be applied as a smart drug delivery system with the help of an external magnetic field or it can be used as a powerful antibiotic agent along with other antibiotics that can form a shell on its structure.