Solution Blow-Spun Poly (Ethylene Oxide)-Polysulfone Bicomponent Fibers-Characterization of Morphology, Structure, and Properties

Solution blow spinning was used to prepare nonwoven bicomponent fibers constituted by poly (ethylene oxide)-Polysulfone (PEO-PSF). As a new material, deep characterization was carried out to have a database to understand final performance regarding its multiple functions as a potential material for biomedical applications. The morphology was studied by field emission scanning electron and transmission electron microscopy and optical profilometry. Structural characterization was carried out by Fourier transform infrared spectroscopy and thermal degradation by thermogravimetric analysis. Additionally, wettability and mechanical behavior were studied by contact angle measurements and tensile tests, respectively. The bicomponent material was constituted of fibers with a structure mainly described by a core-shell structure, where the PSF phase is located at the center of the fibers, and the PEO phase is mainly located at the outer parts of the fibers, leading to a kind of shell wall. The study of possible interactions between different phases revealed them to be lacking, pointing to the presence of an interface core/shell more than an interphase. The morphology and roughness of the bicomponent material improved its wettability when glycerol was tested. Indeed, its mechanical properties were enhanced due to the PSF core provided as reinforcement material.

Cytotoxic effects of chitosan nanoparticles containing Zataria multiflora essential oil against human breast and melanoma cells

Background

Breast cancer is the most common cancer among women, and melanoma incidence increases worldwide. The emergence of drug resistance and side effects of chemotherapy drugs has led to a great deal of attention being paid to the development of natural medicines, especially using essential oil. The preparation of essential oil-based nanoformulation has thus recently received more attention.

Results

In this study, chitosan nanoparticles (ChiNPs) containing Zataria multiflora essential oil with a particle size of 177 ± 10 nm, a narrow particle size distribution (SPAN 0.96), and a cubic-like shape were first prepared. IC50 values of the prepared nanoformulation against human melanoma (A-375) and breast cancer cell lines (MCF-7 and MDA-MB-468) were obtained as 32 (12–84), 46 (32–67), and 105 (85–131) µg/mL. Besides, an electrospun polycaprolactone–polyethylene oxide scaffold was prepared as a dressing after treatment with the nanoformulation. Fourier transform infrared analysis confirmed the scaffold's preparation as well as successful loading of the essential oil in chitosan nanoparticles. Furthermore, the scaffold did not show a cytotoxic effect on A-375, MCF-7, and MDA-MB-468, and its surface was hydrophobic as the water contact angle with the surface was 136.5°.

Conclusions

The prepared prototype with natural ingredients and high efficacy could be considered for further consideration in vivo study or complementary medicine.

Graphical abstract

Dual drug delivery of vancomycin and imipenem/cilastatin by coaxial nanofibers for treatment of diabetic foot ulcer infections

Diabetic foot ulcer infections are the main causes of hospitalization in diabetics. The present study aimed to develop vancomycin and imipenem/cilastatin loaded core-shell nanofibers to facilitate the treatment of diabetic foot ulcers. Therefore, novel core-shell nanofibers composed of polyethylene oxide, chitosan, and vancomycin in shell and polyvinylpyrrolidone, gelatin, and imipenem/cilastatin in core compartments were prepared using the electrospinning technique. The nanofibers were characterized using scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectroscopy, tensile test, and drug release. The antibacterial activity of drug-loaded nanofibers in different drugs concentrations was evaluated against Methicillin-resistant Staphylococcus aureus (MRSA), Escherichia coli, and Pseudomonas aeruginosa by disk diffusion method. Furthermore, the cytotoxicity of fibers was investigated by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide assay. The obtained results showed that the prepared nanofibers were smooth having a core-shell structure with almost no cytotoxicity. The nanofibrous mats exhibited significant antibacterial activity against S. aureus and MRSA with the inhibition zones of 2.9 and 2.5 cm and gram-negative bacteria species of E. coli and P. aeruginosa with the inhibition zones of 1.9 and 2.8 cm, respectively. With respect to the significant antibacterial activities of these nanofibrous mats, they might be used as suitable drug delivery devices not only for diabetic foot ulcer infections but also for other chronic wounds.

R. R, A. S. Tailored design of polyurethane based fouling-tolerant nanofibrous membrane for water treatment

Polyurethane (PU) nanofibers have gained attention due to their good mechanical properties and water resistance.

Novel Electrospun Polylactic Acid Nanocomposite Fiber Mats with Hybrid Graphene Oxide and Nanohydroxyapatite Reinforcements Having Enhanced Biocompatibility

Graphene oxide (GO) and a nanohydroxyapatite rod (nHA) of good biocompatibility were incorporated into polylactic acid (PLA) through electrospinning to form nanocomposite fiber scaffolds for bone tissue engineering applications. The preparation, morphological, mechanical and thermal properties, as well as biocompatibility of electrospun PLA scaffolds reinforced with GO and/or nHA were investigated. Electron microscopic examination and image analysis showed that GO and nHA nanofillers refine the diameter of electrospun PLA fibers. Differential scanning calorimetric tests showed that nHA facilitates the crystallization process of PLA, thereby acting as a nucleating site for the PLA molecules. Tensile test results indicated that the tensile strength and elastic modulus of the electrospun PLA mat can be increased by adding 15 wt % nHA. The hybrid nanocomposite scaffold with 15 wt % nHA and 1 wt % GO fillers exhibited higher tensile strength amongst the specimens investigated. Furthermore, nHA and GO nanofillers enhanced the water uptake of PLA. Cell cultivation, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and alkaline phosphatase tests demonstrated that all of the nanocomposite scaffolds exhibit higher biocompatibility than the pure PLA mat, particularly for the scaffold with 15 wt % nHA and 1 wt % GO. Therefore, the novel electrospun PLA nanocomposite scaffold with 15 wt % nHA and 1 wt % GO possessing a high tensile strength and modulus, as well as excellent cell proliferation is a potential biomaterial for bone tissue engineering applications.

Cooperative fabrication of ternary nanofibers with remarkable solvent and temperature resistance by electrospinning

PVA/PAA/SiO₂ ternary organic–inorganic composite nanofibrous mats are successfully prepared by a cooperative fabrication via electrospinning. The reaction between PVA, PAA and hydrolytic TEOS are proposed to endow the ternary nanofibers with remarkable solvent and temperature resistance, as well as the great mechanical property.