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Electrospinning has emerged as one of the major technologies for designing and fabricating tissue engineering membranes. The resemblance of the electrospun fiber structure to blood capillaries endowed them with unique capabilities to mimic the native tissue biological characteristics, while the high surface‐to‐volume ratio enables them to exert a controlled release of drug directly to the exposed interstitial tissue. This research attempts to compare the characteristics of different electrospun polyvinyl alcohol/hyaluronic acid (PVA/HA) composite material nanofibrous membranes in order to identify the optimal material‐fabrication combination for wound dressing and skin tissue engineering applications. Far‐field electrospinning equipped with both rotatory and wire collectors is considered for membrane fabrication. PVA with different concentrations and molecular weights of HA are electrospun as nanofibrous membranes considering a voltage of 30 kV on both types of collectors. Comprehensive characterization is conducted including morphological, chemical, thermal, mechanical, and in vitro mucoadhesion analysis. In vitro cell viability/proliferation studies are also carried out and pointed out that the designed membranes are cytocompatible, and able to support keratinocytes proliferation. All these results proved that the fabricated PVA/HA nanofibrous membranes are suitable for wound dressing and skin tissue engineering applications, the optimal material‐fabrication combination is also determined. [ABSTRACT FROM AUTHOR]

The topical application of diclofenac for the management of inflammation in rheumatoid arthritis has minimized systemic adverse effect by providing local therapeutic action around the joints. Capsaicin - a naturally occurring compound obtained from plants of the genus Capsicum has antiinflammatory and analgesic property which when combined with diclofenac may lead to enhanced activity. Therefore, a diclofenac-capsaicin emulgel topical formulation was developed and evaluated for its anti-inflammatory activity. Emulgel formulations containing capsaicin, diclofenac, or diclofenac-capsaicin were prepared and subjected to physicochemical characterization, anti-inflammatory activity, skin irritation test and histopathology study in rats. All the formulations had off-white, smooth texture, and glossy appearance. The pH and viscosities of all formulations ranged from 5.51 - 6.23 and 10452 - 52920 mPa.s respectively. All formulations possessed good spreadability and bioadhesive strength, however, the formulations with smaller amount of the alkyl acrylate polymer (1% Carbopol®) as gelling agent had a better spreadability but lesser bioadhesiveness than those with higher gel content (1.5% Carbopol®). The release of diclofenac from all formulations followed the Higuchi model. The diclofenac-capsaicin formulations containing 0.2 and 0.3% capsaicin respectively had a higher anti-inflammatory effect than the diclofenac formulation (p<0.05); the 0.2% formulation had the highest anti-inflammatory effect. The formulations showed no symptoms of allergy nor changes in the microstructure of the skin upon application. The formulations possessed desired physicochemical properties and safety for application to the skin. The spreadability and bioadhesive property of the formulation is dependent on the concentration of carbopol®. The diclofenac-capsaicin emulgel formulation showed improved anti-inflammatory effect when compared with the diclofenac formulation. [ABSTRACT FROM AUTHOR]

Temperature-sensitive liposomes are drug carriers that can encapsulate drug molecules and carry them safely to their target sites for release. They ensure that the encapsulated drug is released for it to become cellularly internalized at the site of action. They also have a wide range of medical applications, however the most popular is chemotherapy. In this study, the objective was to prepare and purify calcein loaded temperature-sensitive liposomes. Calcien loaded liposomes were prepared using the thin-film hydration method and calcein was loaded passively. To separate non-encapsulated calcein from the loaded liposomes three purification methods were utilized: ion exchange beads, centrifugation, and size exclusion methods. The formulated liposomes were characterized for zeta potential, average particle size, phase transition temperature, and release of loaded calcein molecules at 21, 37, and 45°C. Average size of temperature-sensitive liposomes after preparation and purification was < 200 nm and the poly-disparity index < 0.2. The stability and release efficiency of the temperaturesensitive liposome formulation at 37°C in 4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid (HEPES) buffer solution and 5% Foetal bovine serum was optimal with a percentage leakage of less than 5% in both media. The release ratio, which was calculated as the ratio of fluorescence intensity of calcein in heated temperature-sensitive liposomes (45°C) to the fluorescence intensity of non-heated temperature-sensitive liposomes at room temperature (R= I21°C/I45°C) was 1.489, the target-release ratio to be achieved was 1.5. The application of temperature-sensitive liposome formulations in the delivery of anticancer drugs will be beneficial as they exhibited low drug leakage and efficient release. [ABSTRACT FROM AUTHOR]

Objectives: Multi-drug resistant bacteria have been implicated in various debilitating infections that have led to life loss. This study developed an approach to tackle multidrug resistant Acinetobacter baumannii infection in a chronic wound model through A. baumannii phage encapsulation with resuspension in hydrogel. Materials and Methods: Two isolates of A. baumannii-specific lytic phases ɸAB140 and ɸAB150 alone, in combination (cocktail) encapsulated within a chitosan (CS) microparticle was suspended in CS hydrogel and evaluated for their therapeutic efficacy to ensure bacterial clearance in A. baumannii induced diabetic wound infection. Microencapsulation of the phage was carried out using ionic gelation techniques Biological characterization via cell cytoxicity, in vivo wound healing, histology and histomorphometry was carried out. Results: Two characterized A. baumannii phages (ɸAB140 and ɸAB150), specific to twenty A. baumannii isolates, were isolated. The encapsulated CS microparticle hydrogel exhibited a pH of 5.77 ± 0.05. The wound size reduction was most pronounced in formulation C2, which showed statistically significant wound seize reduction on days 4 and 7, 56.79 ± 2.02% and 62.15 ± 5.11%, respectively. The optimized concentration of C2 was not toxic to the cells as it adequately supported cell growth with a proliferation rate of 215 ± 7.89% compared to control (107.32 ± 4.55%). Conclusion: Microparticle carrier technology was used to show the lytic activity against multi drug-resistant A. baumannii. In vivo results showed significant wound size reduction that was most pronounced in formulation C2 on day 4. [ABSTRACT FROM AUTHOR]

Studies have been carried out on bovine bone due to its abundance and large quantity of hydroxyapatite (HAP) in it while caprine bone has been understudied. In this study, locally sourced bovine and caprine bones were washed in distilled water, defatted at 120°C for 1.5 hr in a pressure pot, ball-milled, sieved to 150 µm particle size and characterised. The X-ray fluorescence (XRF) and Energy dispersive X-Ray Spectroscopy (EDS) analysis revealed calcium, phosphorus and carbon as the main components. Both bones contained carbon and oxygen due to the presence of organic collagen but the quantity in caprine bone was a bit higher as revealed by the Fourier Transform Infrared Spectroscopy (FTIR) and EDS spectra. A slight difference in thermal decomposition patterns was recorded while X-Ray diffraction analysis (XRD) revealed the presence of identical functional phases. The microstructures showed needle-like and pebble-like shapes for bovine and caprine respectively, also on visual examination of the Scanning Electron Micrograph (SEM), the bovine samples tended to have particle surface roughness more than caprine. Consequently, the chemical properties of both bone raw samples were insignificantly different from each other except for collagen composition and morphology. [ABSTRACT FROM AUTHOR]