Innovative drug vehicle for local treatment of inflammatory skin diseases: Ex vivo and in vivo screening of five topical formulations containing poly(lactic acid) (PLA) nanoparticles.

One of the main goals in the galenic development of innovative topical treatment options for inflammatory skin diseases such as psoriasis and atopic dermatitis is to selectively deliver the drug at the inflammation site. Recent studies have highlighted the beneficial use of polymeric nanoparticles for anti-inflammatory therapy and topical anti-inflammatory drug delivery due to their ability to form a drug reservoir retaining the drug locally at the site of action. Our approach consisted in designing innovative topical semi-solid formulations of poly(lactic acid) (PLA) nanoparticles as anti-inflammatory drug vehicles for local treatment of inflammatory skin diseases. In the course of this work, five topical formulations containing fluorescent PLA nanoparticles were initially developed, and then screened depending on their physico-chemical properties, toxicity and delivery efficacy. The penetration and permeation of a fluorophore vectorized by PLA nanoparticles into healthy and inflammatory skin were assessed using an alternative device to classical Franz cells: VitroPharma. All these investigations led to the selection of two satisfactory formulations out of five initial candidates.

Percutaneous absorption of benzophenone-3 loaded lipid nanoparticles and polymeric nanocapsules: A comparative study.

For the last years, the increase of the number of skin cancer cases led to a growing awareness of the need of skin protection against ultraviolet (UV) radiations. Chemical UV filters are widely used into sunscreen formulations as benzophenone-3 (BP-3), a usually used broad spectrum chemical UV filter that has been shown to exercise undesirable effects after topical application. Innovative sunscreen formulations are thus necessary to provide more safety to users. Lipid carriers seem to be a good alternative to formulate chemical UV filters reducing their skin penetration while maintaining good photo-protective abilities. The aim of this work was to compare percutaneous absorption and cutaneous bioavailability of BP-3 loaded into solid lipid nanoparticles (SLN), nanostructured lipid carriers (NLC), nanostructured polymeric lipid carriers (NPLC) and nanocapsules (NC). Particle size, zeta potential and in vitro sun protection factor (SPF) of nanoparticle suspensions were also investigated. Results showed that polymeric lipid carriers, comprising NPLC and NC, significantly reduced BP-3 skin permeation while exhibiting the highest SPF. This study confirms the interesting potential of NPLC and NC to formulate chemical UV filters.

Aqueous dispersions of organogel nanoparticles - potential systems for cosmetic and dermo-cosmetic applications.

OBJECTIVE: The preparation and physicochemical characterization of organogel nanoparticles dispersed in water have been developed. These systems could be employed as nanocarrier for cosmetic applications or as hydrophobic reservoirs for drug delivery. METHODS: Gelled particles of organic liquid and 12-hydroxystearic acid (organogelator) were obtained by hot emulsification (T>Tgel), with a surfactant (acetylated glycol stearate) and polymers (sodium hyaluronate and polyvinyl alcohol) as stabilizing agents, and cooling at room temperature (T