Authors: P. Supmuang, S. Wanichwecharungruang
Affilation: Chulalongkorn University, Thailand
Pages: 130 - 133
Keywords: retinal, chitosan, hair follicle, skin, delivery
Vitamin A and its derivatives including retinaldehyde possess serious instability problem. To continuously supply skin with un-degraded retinaldehyde, nanoparticles which could penetrate into skin via hair follicles and then slowly release this vitamin A derivative were designed and fabricated. The 200-300 nm dry-size particles were prepared by covalently linked retinaldehyde to succinylchitosan and then allowed the obtained retinilidene-succinylchitosan (RSC) to self-assemble into nanoparticles in water. Loading of vitamin E into the RSC particles was carried out to further improve the stability of the grafted retinilidene moieties in the particles. The vitamin E-loaded RSC particles possessed triple protection barriers for the retinilidene moieties, the chemical barrier via imine bond, the physical barrier from the chitosan matrix around the retinilidene core, and the antioxidative barrier of the vitamin E which was confined to be in the same location with the retinilidene moieties. Covalently labeling the RSC particles with fluorophore rhodamine B (RhoB) was carried out and ex-vivo experiment on porcine ear skin using confocal fluorescent microscopic analysis showed skin penetration of the RhoB-labeled RSC particles via hair follicles followed with clear retinaldehyde release from the particles into skin tissue.