RESUMO
The aim of the study was to develop and evaluate the Ginkgo biloba nanocomplex gel (GKNG) as a long-acting formulation for the wound healing potential. Pharmaceutical analysis showed an average particle size of 450.14 ± 36.06 nm for GKNG, zeta potential +0.012 ± 0.003 mV, and encapsulation efficiency 91 ± 1.8%. The rheological analysis also showed the optimum diffusion rate and viscosity needed for topical drug delivery. Fourier transform infrared spectroscopy (FTIR), powder X-ray diffractometry (PXRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM) analysis further confirmed the success of GKNG. The in vivo study showed increments in the antioxidant enzymes superoxide dismutase (SOD) and glutathione peroxidase (GPx) and a lower level of lipid peroxidation (MDA) after GKNG treatment. The GKNG group showed upregulations in collagen type I, as alpha 1 collagen (COL1A1), and collagen type IV, as alpha 1 collagen (COL4A1). Furthermore, the in vivo study showed increments in hydroxyproline, epidermal growth factor (EGF), vascular endothelial growth factor (VEGF), and transforming growth factor-beta 1 (TGF-ß1) after the GKNG. Additionally, GKNG effectively increased the wound contraction compared to GK gel and sodium alginate (SA) gel. Based on the in vitro and in vivo evaluation, GKNG effectively accelerated wound healing by modulation of antioxidant enzymes, collagens, angiogenic factors, and TGF-ß1.
RESUMO
In this work, silver (Ag) decorated reduced graphene oxide (rGO) coated with ultrafine CuO nanosheets (Ag-rGO@CuO) was prepared by the combination of a microwave-assisted hydrothermal route and a chemical methodology. The prepared Ag-rGO@CuO was characterized for its morphological features by field emission scanning electron microscopy and transmission electron microscopy while the structural characterization was performed by X-ray diffraction and Raman spectroscopy. Energy-dispersive X-ray analysis was undertaken to confirm the elemental composition. The electrochemical performance of prepared samples was studied by cyclic voltammetry and galvanostatic charge-discharge in a 2M KOH electrolyte solution. The CuO nanosheets provided excellent electrical conductivity and the rGO sheets provided a large surface area with good mesoporosity that increases electron and ion mobility during the redox process. Furthermore, the highly conductive Ag nanoparticles upon the rGO@CuO surface further enhanced electrochemical performance by providing extra channels for charge conduction. The ternary Ag-rGO@CuO nanocomposite shows a very high specific capacitance of 612.5 to 210 Fg-1 compared against rGO@CuO which has a specific capacitance of 375 to 87.5 Fg-1 and the CuO nanosheets with a specific capacitance of 113.75 to 87.5 Fg-1 at current densities 0.5 and 7 Ag-1, respectively.
RESUMO
This article aims at the synthesis of highly stable γ-Fe2O3 magnetic nanoparticles and their ferrofluids using different base liquids such as liquid paraffin, motor oil and sunflower oil for heat transfer applications. Phase and morphology of the synthesized nanoparticles were probed using XRD, SEM and FTIR spectroscopy. The average nanoparticle size of γ-Fe2O3 magnetic nanoparticles was found to be 13 nm. Stability of the ferrofluids was monitored by visually observing the aggregation nature of the nanoparticles for 180 days. The ferrofluid prepared using motor oil as a base fluid exhibited high stability (for more than 1 year) and a mean enhancement of 77% in thermal conductivity at 1.5 vol% nanoparticles was observed as compared to base fluid. The viscosity of the ferrofluids was also measured and found to be 18, 38 and 8 cP at 27 °C for the liquid paraffin based, motor oil based and sunflower oil based ferrofluid, respectively.
