Transdermal Sustained Release Properties and Anti-Photoaging Efficacy of Liposome-Thermosensitive Hydrogel System.

Drug delivery systems have become a research priority in the biomedical field. The incorporation of liposomes to hydrogels further forms more robust multifunctional systems for more effective and sustained topical drug delivery. In this study, carboxymethyl-modified chitosan/hyaluronic acid (CMC/HA, CMH) thermosensitive hydrogel was developed for sustained transdermal delivery of liposomes. Hydrogels were crosslinked by hydrogen bonding, hydrophobic interaction and electrostatic interaction. The gel properties could be regulated by substitution degree (DS), and when DS = 18.20 ± 0.67% (CMH2), the gel temperature was 37.8°C, allowing rapid gelation at body temperature (315 s). Moreover, CMH2 hydrogel had suitable spreadability (17.7-57.2 cm 2 ), viscosity (2133.4 mPa·s) and porous structure, which facilitated its adhesion and application on the skin and liposomes delivery. In vitro transdermal results showed that the hydrogel retarded the liposomes release, and the release rate of AA2G was 33.92-49.35% in 24 h. Hydrogel avoided the rapid clearance of liposomes from the skin and improved the skin retention, achieving the long-term release of bioactive components. Liposome-hydrogel system more efficiently promoted the anti-photoaging effect of AA2G on skin, reducing epidermal thickness, melanin deposition and lipid oxidative damage and increasing collagen density. Therefore, liposome-hydrogel systems have been proposed as multifunctional delivery systems for sustained transdermal delivery. This article is protected by copyright. All rights reserved.