Follicular targeting has gained more attention in recent decades, due to the possibility of obtaining a depot effect in topical administration and its potential as a tool to treat hair follicle-related diseases. Lipid core ethyl cellulose lipomers were developed and optimized, following which characterization of their physicochemical properties was carried out. Dexamethasone was encapsulated in the lipomers (size, 115 nm; polydispersity, 0.24; zeta-potential (Z-potential), +30 mV) and their in vitro release profiles against dexamethasone in solution were investigated by vertical diffusion Franz cells. The skin biodistribution of the fluorescent-loaded lipomers was observed using confocal microscopy, demonstrating the accumulation of both lipomers and fluorochromes in the hair follicles of pig skin. To confirm this fact, immunofluorescence of the dexamethasone-loaded lipomers was carried out in pig hair follicles. The anti-inflammatory (via TNFα) efficacy of the dexamethasone-loaded lipomers was demonstrated in vitro in an HEK001 human keratinocytes cell culture and the in vitro cytotoxicity of the nanoformulation was investigated.
Keywords: alopecia areata; biodistribution; dexamethasone; ethyl cellulose; follicular targeting; lipid polymer hybrid nanocapsules; lipomers; skin.