Prolonged skin retention of clobetasol propionate by bio-based microemulsions: a potential tool for scalp psoriasis treatment.

Novel effective and cosmetically acceptable formulations are needed for the treatment of scalp psoriasis, due to the poor efficacy of the current products. The challenge in developing safe, efficient, and convenient delivery systems for this drug was addressed in the present work by formulating clobetasol propionate-loaded W/O microemulsions (MEs). Pseudo-ternary phase diagrams were constructed by using a combination of biocompatible and biodegradable excipients. Characterization studies demonstrated that selected MEs had suitable technological features such as being Newtonian fluids, possessing low viscosity, and high thermodynamic stability. Photomicrographs showed a significant alteration of the skin structure after treatment with MEs, and a preferential concentration of these in the stratum corneum and epidermis. These data, together with ex vivo permeation results, suggested an enhanced topical targeted effect due to an increased drug retention efficacy in the upper skin layers, as desired. Moreover, the bio-based excipients selected could contribute to the healing of the psoriatic scalp. In this way, the improvement of clobetasol efficacy is combined with the useful properties of the microemulsion components and with environmental safety.

Formulation and Evaluation of Organogels Containing Hyaluronan Microparticles for Topical Delivery of Caffeine.

Cellulite is a dermal disorder including the extracellular matrix, the lymphatic and microcirculatory systems and the adipose tissue. Caffeine is used as the active moiety depending its preventive effect on localization of fat in the cellular structure. Hyaluronic acid (hyaluronan-HA) is a natural constituent of skin that generates formation and poliferation of new cells having a remarkable moisturizing ability. The aim of this study is to formulate HA microparticles loaded with caffeine via spray-drying method. Resulting microparticle formulations (33.97 ± 0.3 µm, span < 2, 88.56 ± 0.42% encapsulation efficiency) were distributed in lecithin organogels to maintain the proper viscosity for topical application. Following the characterization and cell culture studies, in vitro drug release and ex vivo permeation studies were performed. The accumulated amount of caffeine was twice higher than the aqueous solution for the microparticle-loaded organogels at 24 h (8262,673 µg/cm2versus 4676,691 µg/cm2). It was related to the sustained behaviour of caffeine release from the microparticles. As a result, lecithin organogel containing HA-encapsulated microparticles could be considered as suitable candidate formulations for efficient topical drug delivery system of caffeine. In addition to that, synergistic effect of this combination appears as a promising approach for long-acting treatment of cellulite.

Terbinafine hydrochloride loaded liposome film formulation for treatment of onychomycosis: in vitro and in vivo evaluation.

Onychomycosis is a fungal infection of nail unit that is caused by dermatophytes. Oral Terbinafine hydrochloride (TBF-HCl) is being used for the treatment of onychomycosis since 24 years. The side effects caused by the systemic application and limitations of topical administration of this drug regarding the diffusion through nail lead to the development of a new formulation based on, TBF-HCl-loaded liposome. The newly obtained film formulations were prepared and characterized via several parameters, such as physical appearance, drug content, thickness, bioadhesive properties and tensile strength. In vitro and ex vivo permeation studies were performed to select an optimum film formulation for antifungal activity to show the efficiency of formulations regarding the treatment of onychomycosis. The in vitro release percentages of drug were found 71.6 ± 3.28, 54.4 ± 4.26, 56.1 ± 7.48 and 46.0 ± 2.43 for liposome loaded pullulan films (LI-P, LII-P) and liposome loaded Eudragit films (LI-E, LII-E), respectively. The accumulated drug in the nail plates were found 31.16 ± 4.22, 24.81 ± 5.35, 8.17 ± 1.81 and 8.92 ± 3.37 for LI-P, LII-P, LI-E and LII-E, respectively, which within therapeutic range for all film formulations. The accumulated drug in the nail plate was found within therapeutic range for all film formulations. The efficacy of the selected TBF-HCl-loaded liposome film formulation was compared with TBF-HCl-loaded liposome, ethosome, liposome poloxamer gel and ethosome chitosan gel formulations. It was found that TBF-HCl-loaded liposome film formulation had better antifungal activity on fungal nails which make this liposome film formulation promising for ungual therapy of fungal nail infection.

A New Application Route of Nitrofurantoin: Preparation and Characterization of Novel Transdermal Formulations.

OBJECTIVES: Nitrofurantoin is widely used in the prophylaxis of urinary-tract infections. The aim of this study was to develop and characterize innovative transdermal formulations of nitrofurantoin, to increase the patient compliance and decrease the adverse effects such as nausea and vomiting which limit the drug use in long-term. METHODS: Nitrofurantoin loaded microemulsion, gel (hydrogel, lipogel and DMSO gel) and film formulations were prepared and characterized via several parameters. Ex-vivo drug permeation studies were performed to determine the amount of drug permeated through the rat skin. In in-vivo studies, in order to detect nitrofurantoin in urine, the selected formulations were applied to male Wistar rats transdermally. Also, skin irritation tests (transepidermal water loss and erythema) were performed. RESULTS: All nitrofurantoin loaded formulations were prepared successfully and were stable at +4°C for 3 months. 13%, 16%, 32.5%, 36.5% and 39% of drugs permeated through the rat skin in the 168th hour for hydrogel, lipogel, film, microemulsion and DMSO gel, respectively. Only with film and DMSO gel formulations, nitrofurantoin was detected in urine. Transepidermal water loss was increased compared to basal level in film type formulations (p<0.05). However, in erythema experiments there was no difference (p>0.05). CONCLUSION: There is no approved transdermal formulation of nitrofurantion on the market. Therefore, the prepared film formulations could be an alternative due to their high penetration through the rat skin, the presence of nitrofurantoin in urine and because they cause no irritation on the skin.

Bio-based topical system for enhanced salicylic acid delivery: preparation and performance of gels.

OBJECTIVES: New salicylic acid (SA)-loaded gels were developed using excipients made from renewable materials, and our goal was to improve drug permeation in the topical treatment of acne vulgaris. METHODS: We studied the preparation parameters to obtain suitable gel formulations. Only naturally occurring polymers were used as gelling agents. Two hydrogels and three lipogels were selected and characterized in terms of drug loading, pH, viability cells, rheology, mechanical properties and in vitro permeation; these hydrogels and lipogels were compared with the traditional ointment. We also evaluated skin parameters before and after gel application. KEY FINDINGS: The formulations that we studied are non-Newtonian fluids; they have high drug loading and suitable mechanical properties. Lipogels exhibit a slower and more linear in vitro permeation profile compared with hydrogels. The different vehicles that we used affected drug permeation and improve patient compliance. Cytotoxicity studies suggest that all of the formulations are non-toxic. CONCLUSIONS: Lipogels demonstrate appropriate technological features and improved performance compared with the traditional ointment with regard to their composition. Lipogels may represent a new bio-based topical system for SA delivery. The use of 'green' excipients leads to 'skin-friendly' formulations that are able to satisfy environmental safety.

Evaluation of characteristics and in vitro antioxidant properties of RSV loaded hyaluronic acid-DPPC microparticles as a wound healing system.

Resveratrol (RSV) was incorporated into microparticles by spray drying to treat chronic wounds such as diabetic ulcers. RSV was chosen due to its defense mechanisms as the formation of free radicals delays the healing process. RSV was loaded into microparticles consisting of dipalmitoylphosphatidylcholine (DPPC) and hyaluronic acid (HA), a polysaccharide naturally present within the skin, known to contribute to the healing process. Microparticles were evaluated in terms of production yield, size distribution, encapsulation efficiency, morphology, specific surface area, thermal properties and water content. Spherical and homogenous microparticles (span ≤ 2) in a size range between 20 and 30 µm were obtained with high encapsulation efficiency (≥ 97%). The effect of enzymes (hyaluronidase, phospholipase and lipase) on RSV release showed a dose-dependent pattern followed by a slow release stage. Cytotoxicity/proliferation and oxidative stress parameters (glutathione, oxidized glutathione, glutathione peroxidase, malondialdehyde, superoxide dismutase) obtained from human dermal fibroblast cell cultures revealed that formulations increased cell proliferation and the presence of RSV decreased oxidation in cells. RSV-loaded HA-DPPC microparticles appear as a promising formulation for wound healing due to synergistic effect of the ingredients.

Novel topical formulations of Terbinafine-HCl for treatment of onychomycosis.

Terbinafine hydrochloride (TBF-HCl) is an active substance that is using for treatment of onychomycosis. Onychomycosis is a fungal infection which is the most common disease of nail plate. The nail plate is a barrier which prevents effective topical treatment of ungual disorders. In this study, TBF-HCl loaded liposome and ethosome formulations and also gel form of these formulations were prepared. The formulations were characterized and in vitro and ex vivo release studies were performed. Nail characterization studies were also performed to examine the effect of formulations and experimental conditions on nail surface. As a result, all formulations can serve as efficient formulations for ungual application of TBF-HCl. By the way, the results of the accumulation studies suggested that liposome poloxamer gel formulation could be promising system for ungual drug delivery due to the better accumulation and easier application of the formulation.