Voriconazole incorporated nanofiber formulations for topical application: preparation, characterization and antifungal activity studies against Candida species.

In this study, voriconazole (VCZ) incorporated polyvinyl alcohol/sodium alginate electrospun nanofibers were produced and, then crosslinked with glutaraldehyde for topical antifungal treatment. The nanofibers were characterized in terms of fiber size, surface morphology, and compatibility between drug-polymer and polymer-polymer using scanning electron microscopy, atomic force microscopy, attenuated total reflection-Fourier transform infrared spectroscopy, and high pressure liquid chromatography. After optimization studies, in vitro drug release, skin penetration, and deposition studies were performed using Franz diffusion cells. Antifungal activities of the nanofiber formulations against Candida albicans, Candida tropicalis, and Candida parapysilosis strains were evaluated using susceptibility test and subsequently time-kill study was performed against C. albicans. The cytotoxicity study was performed using 4-succinate dehydrogenase viability assay on mouse fibroblast cell line. The release rate of VCZ from crosslinked nanofibers was slower than that of non-crosslinked nanofibers and Higuchi kinetic model best fitted to the in vitro release data of both of formulations. VCZ deposited in deeper skin layers from nanofiber formulations was higher than that of the control formulation (VCZ solution in propylene glycol (1% (w/v)). According to the susceptibility and time-kill studies, all of the nanofiber formulations showed antifungal activity against C. albicans with confirming no cytotoxicity on mouse fibroblast cells.

Colloidal nanocarriers for the enhanced cutaneous delivery of naftifine: characterization studies and in vitro and in vivo evaluations.

In topical administration of antifungals, the drugs should pass the stratum corneum to reach lower layers of the skin in effective concentrations. Thus, the formulation of antifungal agents into a suitable delivery system is important for the topical treatment of fungal infections. Nanosized colloidal carriers have gained great interest during the recent years to serve as efficient promoters of drug penetration into the skin. Microemulsions are soft colloidal nanosized drug carriers, which are thermodynamically stable and isotropic systems. They have been extensively explored for the enhancement of skin delivery of drugs. This study was carried out to exploit the feasibility of colloidal carriers as to improve skin transport of naftifine, which is an allylamine antifungal drug. The microemulsions were formulated by construction of pseudoternary phase diagrams and composed of oleic acid (oil phase), Kolliphor(®) EL or Kolliphor(®) RH40 (surfactant), Transcutol(®) (cosurfactant), and water (aqueous phase). The plain and drug-loaded microemulsions were characterized in terms of isotropy, particle size and size distribution, pH value, refractive index, viscosity, and conductivity. The in vitro skin uptake of naftifine from microemulsions was studied using tape stripping technique in pig skin. The drug penetrated significantly into stratum corneum from microemulsions compared to its marketed cream (P<0.05). Moreover, the microemulsion formulations led to highly significant amount of naftifine deposition in deeper layers of skin than that of commercial formulation (P<0.001). Microemulsion-skin interaction was confirmed by attenuated total reflectance - Fourier transformed infrared spectroscopy data, in vitro. The results of the in vivo tape stripping experiment showed similar trends as the in vitro skin penetration study. Topical application of the microemulsion on human forearms in vivo enhanced significantly the distribution and the amount of naftifine penetrated into the stratum corneum as compared to the marketed formulation (P<0.05). The relative safety of the microemulsion formulations was demonstrated with 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide viability test. This study indicated that the nanosized colloidal carriers developed could be considered as an effective and safe topical delivery system for naftifine.

Colloidal carriers of isotretinoin for topical acne treatment: skin uptake, ATR-FTIR and in vitro cytotoxicity studies.

Acne vulgaris is the chronical, multifactorial and complex disease of the pilosebaceous unit in the skin. The main goal of the topical therapy in acne is to target the drug to epidermal and deep dermal regions by minimizing systemic absorption . Isotretinoin, a retinoic acid derivative, is the most effective drug in acne pathogenesis. Because systemic treatment may cause many side effects, topical isotretinoin treatment is an option in the management of acne. However, due to its high lipophilic character, isotretinoin tends to accumulate in the upper stratum corneum, thus its penetration into the lower layers is limited, which restricts the efficiency of topical treatment. Microemulsions are fluid, isotropic, colloidal drug carriers that have been widely studied as drug delivery systems. The percutaneous transport of active agents can be enhanced by microemulsions when compared with their conventional formulations. The purpose of this study was to evaluate microemulsions as alternative topical carriers for isotretinoin with an objective to improve its skin uptake. After in vitro permeation studies, the dermal penetration of isotretinoin from microemulsions was investigated by tape stripping procedure. Confocal laser scanning microscopy provided insight about the localization of the drug in the skin. The interaction between the microemulsion components and stratum corneum lipids is studied by ATR-FTIR spectroscopy. The relative safety of the microemulsions was assessed in mouse embryonic fibroblasts using MTT viability test. The results indicate that microemulsion-based novel colloidal carriers have a potential for enhanced skin delivery and localization of isotretinoin.

Design and in vivo evaluation of emulgel formulations including green tea extract and rose oil.

Prevention of skin aging and its treatment is an emerging field for development of new formulations in cosmetics. Accordingly, plant extracts with antioxidant properties are beneficial cosmetic ingredients for this purpose. This study was aimed at developing a stable and easily manufactured emulgel including green tea extract and rose oil that is effective on the barrier function and hydration of the skin. An emulgel formulation containing 20 % green tea extract and 5 % rose oil was designed as a result of pre-formulation studies. Physicochemical characterization, in vitro stability studies, in vivo water content of the stratum corneum and transepidermal water loss studies were carried out afterwards. In vivo studies on ten female subjects were evaluated by using non-invasive skin bioengineering techniques. Finally, a cosmetically acceptable, stable and effective emulgel formulation for skin barrier function with good hydrating properties was obtained for skin hydration, protection and anti-aging purposes.