Preparation, Characterization and ex vivo Skin Permeability Evaluation of Type I Collagen-Loaded Liposomes

In the present study, we prepared collagen liposomes with the addition of polyol, which is expected to not only increase the solubility of collagen but also improve skin penetration.Collagen liposomes were prepared by the film dispersion method, and their characteristics, integrity and biosafety were evaluated by Fourier transform infrared spectroscopy (FTIR), UV-VIS spectroscopy, polyacrylamide gel electrophoresis (SDS-PAGE), dynamic light scattering (DLS) and transmission electron microscope (TEM). The transdermal absorption of collagen and collagen liposomes were tested by an ex vivo horizontal Valia-Chien diffusion cell system.We first demonstrated that collagen extracted from bovine Achilles tendon was type I collagen. The results of DLS measurement and TEM observation showed that the collagen liposomes were spherical in shape with average diameter (75.34±0.93 nm) and maintained high stability at low temperature (4°C) for at least 42 days without toxicity. The encapsulation rate of collagen liposomes was 57.80 ± 0.51%, and SDS-PAGE analysis showed that collagen was intact in liposomes. Finally, permeability studies indicated that the collagen-loaded liposomes more easily penetrated the skin compared to collagen itself.This study proposed a new method to improve the bioavailability and permeability of bovine type I collagen, which improves the applicability of collagen in biomedicine, cosmeceuticals and pharmaceutical industries.