Development and Skin Penetration Pathway Evaluation Using Confocal Laser Scanning Microscopy of Microemulsions for Dermal Delivery Enhancement of Finasteride.

This study aimed to develop microemulsions using poloxamer 124 as a surfactant to improve the skin penetration of finasteride and to investigate the skin penetration pathways of these microemulsions by colocalization techniques using confocal laser scanning microscopy (CLSM). The prepared finasteride-loaded microemulsions had average particle sizes ranging from 80.09 to 136.97 nm with particle size distributions within acceptable ranges and exhibited negative surface charges. The obtained microemulsions could significantly increase the skin penetration of finasteride compared to a finasteride solution. According to the skin penetration pathway evaluation conducted with CLSM, the microemulsions were hair follicle-targeted formulations due to penetration via the transfollicular pathway as a major skin penetration pathway. Additionally, this study found that the microemulsions also penetrated via the intercluster pathway more than via the intercellular pathway and transcellular pathway. The intercluster pathway, intercellular pathway, and transcellular pathway were considered only minor pathways.

Electrospun chitosan/polyvinyl alcohol nanofibre mats for wound healing.

Chitosan (CS) aqueous salt blended with polyvinyl alcohol (PVA) nanofibre mats was prepared by electrospinning. CS was dissolved with hydroxybenzotriazole (HOBt), thiamine pyrophosphate (TPP) and ethylenediaminetetraacetic acid (EDTA) in distilled water without the use of toxic or hazardous solvents. The CS aqueous salts were blended with PVA at different weight ratios, and the effect of the solution ratios was investigated. The morphologies and mechanical and swelling properties of the generated fibres were analysed. Indirect cytotoxicity studies indicated that the CS/PVA nanofibre mats were non-toxic to normal human fibroblast cells. The CS-HOBt/PVA and CS-EDTA/PVA nanofibre mats demonstrated satisfactory antibacterial activity against both gram-positive and gram-negative bacteria, and an in vivo wound healing test showed that the CS-EDTA/PVA nanofibre mats performed better than gauze in decreasing acute wound size during the first week after tissue damage. In conclusion, the biodegradable, biocompatible and antibacterial CS-EDTA/PVA nanofibre mats have potential for use as wound dressing materials.

Electrospun chitosan-based nanofiber mats loaded with Garcinia mangostana extracts.

The aim of this study was to prepare electrospun chitosan-based nanofiber mats and to incorporate the fruit hull of Garcinia mangostana (GM) extracts into the mats. Chitosan-ethylenediaminetetraacetic acid/polyvinyl alcohol (CS-EDTA/PVA) was selected as the polymers. The GM extracts with 1, 2 and 3 wt% α-mangostin were incorporated into the CS-EDTA/PVA solution and electrospun to obtain nanofibers. The morphology and diameters of the mats were analyzed using scanning electron microscopy (SEM). The mechanical and swelling properties were investigated. The amount of GM extracts was determined using high-performance liquid chromatography (HPLC). The antioxidative activity, antibacterial activity, extract release and stability of the mats were evaluated. In vivo wound healing tests were also performed in Wistar rats. The results indicated that the diameters of the fibers were on the nanoscale and that no crystals of the extract were observed in the mats at any concentration. The mats provided suitable tensile strength and swelling properties. All of the mats exhibited antioxidant and antibacterial activity. During the wound healing test, the mats accelerated the rate of healing when compared to the control (gauze-covered). The mats maintained 90% of their content of α-mangostin for 3 months. In conclusion, the chitosan-based nanofiber mats loaded with GM extracts were successfully prepared using the electrospinning method. These nanofiber mats loaded with GM extracts may provide a good alternative for accelerating wound healing.

Lysozyme-loaded, electrospun chitosan-based nanofiber mats for wound healing.

In this study, a blend mixture of chitosan-ethylenediaminetetraacetic acid (CS 2 wt%-EDTA) at a weight ratio of 30/70 and polyvinyl alcohol (PVA) solution (10 wt%) was electrospun to produce fibrous mats with lysozyme (10, 20 and 30 wt%) used for wound healing. The morphology and diameter of the electrospun fiber mats with and without lysozyme were analyzed by scanning electron microscopy (SEM). The amount of lysozyme loaded in the nanofiber mats was measured by HPLC. The cell lysis activity of the lysozyme was investigated with Micrococcus lysodeikticus cells as a substrate. The wound healing activity was performed in vivo using male Wistar rats. The SEM images of all lysozyme-loaded fibers show a smooth fiber without beads with an average diameter of 143-209 nm. The amount of lysozyme loaded in the nanofiber mats was slightly decreased when the initial concentration of lysozyme was increased. The rapid lysozyme release from the nanofiber mats was obtained and is dependent on the lysozyme-loading amount. In animal wound healing, lysozyme loaded CS-EDTA nanofiber mats accelerated the rate of wound healing when compared to the controls (gauze). In conclusion, our experiments demonstrated that biomaterials composed of lysozyme loaded CS-EDTA nanofibers have a potential for wound healing.