Methods: Colchicine-loaded transethosomes (TEs) were prepared by the cold method and statistically optimized using three sets of 24 factorial design experiments. The optimized formulations were incorporated into Carbopol 940® gel base. The prepared colchicine-loaded transethosomal gels were further characterized for vesicular size, dispersity, zeta potential, drug content, pH, viscosity, yield, rheological behavior, and ex vivo skin permeation through Sprague Dawley rats' back skin.
Results: The results showed that the colchicine-loaded TEs had aspherical irregular shape, nanometric size range, and high entrapment efficiency. All the formulated gels exhibited non-Newtonian plastic flow without thixotropy. Colchicine-loaded transethosomal gels were able to significantly enhance the skin permeation parameters of the drug in comparison to the non-ethosomal gel.
Conclusion: These findings suggested that the transethosomal gels are promising carriers for the transdermal delivery of colchicine, providing an alternative route for drug administration.
Materials and Methods: Biodegradable polymeric microneedle arrays were fabricated out of poly lactic-co-glycolic acid (PLGA) using the micromolding technique under aseptic conditions, and the morphology of the microneedles was characterized using light microscopy. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis was used to rule out drug-polymer interactions. Standard procedures were used to analyze the prepared microneedle arrays for in vitro drug release and to perform a microneedle insertion test. Enzyme-linked immunosorbent assay was used to quantify rHuKGF.
Results: The PLGA polymer was safe for use in the fabrication of rHuKGF microneedles as there was no interaction between the drug and the polymer. The fabricated rHuKGF microneedle arrays had fully formed microneedles with a height of 600 µm and a base of 300 µm. The drug from the microneedle patch was released in vitro within 30 minutes. The strength of the microneedles in the patch was good, as they were able to reach a depth of 381±3.56 µm into parafilm without any structural change or fracture.
Conclusion: Microneedle transdermal patches were successfully prepared for rHuKGF, and their evaluation suggested excellent quality and uniformity of patch characteristics. This can have potential applications in the therapeutic arena, offering advantages in terms of reduced dosing frequency, improved patient compliance, and bioavailability.
METHODS: This work reports the application of an X-ray microbeam via synchrotron SAXS/WAXS analysis to monitor drug crystallization in the skin, especially in the deeper skin layers. Confocal Raman spectroscopy (CRS) was employed to examine drug distribution in the skin to complement the detection of drug crystallization using SAXS/WAXS analysis.
RESULTS: Following application of saturated drug solutions (ibuprofen, diclofenac acid, and salts), CRS depth profiles confirmed that the drugs generally were delivered to a depth of ~15 - 20 µm in the skin. This was compared with the WAXS profiles that measured drug crystal diffraction at a depth of up to ~25 µm of the skin.
CONCLUSION: This study demonstrates the potential of synchrotron SAXS/WAXS analysis for profiling of drug crystallization in situ in the deeper skin layers without pre-treatment for the skin samples. [Figure: see text].