This article describes the physicochemical properties of chitosan-coated liposomes containing skin-protecting agents, coenzyme Q10 and alpha-lipoic acid (CCAL). CCAL had a spherical shell-core structure and liposomes inverted the surface charge from negative to positive after coating with chitosan. Compared with the uncoated liposome, CCAL had higher zeta potential, larger droplet size and long-term stability. Fourier transform infrared spectroscopy (FTIR) study showed that the driving force for chitosan coating the liposomes was enhanced via hydrogen bonding and ionic bond force between the chitosan and the alpha-lipoic acid. While the encapsulation efficiency (EE) of alpha-lipoic acid also increased by interacting with the chitosan shell. In vitro antioxidant activity study showed an excellent hydroxyl radical scavenging activity of CCAL. In vitro release study displayed a sustained drug release, and in vitro penetration studies promoted the accumulation of drugs in rabbit skin.

The aim of the present study was to prepare nanostructured lipid carriers (NLCs) and nanoemulsions (NEs) with different lipid compositions for delivery of phenylethyl resorcinol (PR) and investigate the effect of the lipid composition on the performance of lipid-based nanocarriers. The optimized nanocarriers were evaluated by photon correlation spectroscopy (PCS), Laser diffraction (LD), encapsulation efficiency, in vitro release and in vitro penetration studies. The particle sizes of all the freshly prepared nanocarriers were in the range of 70-200 nm. PR-NLCs showed higher encapsulation efficiency than PR-NEs. A controlled-release behavior of PR-NLCs was observed in in vitro release studies. In vitro penetration studies demonstrated nanocarriers with smaller particles possessed higher penetration ability. According to the present study, nanocarriers with small particle sizes can be considered as a potential drug delivery system for typical application.