Injectable Hydrogel With Glycyrrhizic Acid and Asiaticoside-Loaded Liposomes for Wound Healing

Open skin wounds increase the risk of infections and can compromise health. Therefore, applying medications to promote healing at the injury site is crucial. In practice, direct drug delivery is often difficult to maintain for a long time due to rapid absorption or wiping off, which reduces the efficiency of wound healing. Consequently, the development of bioactive materials with both antibacterial and wound-healing properties is highly desirable.

This study synthesized liposomes loaded with glycyrrhizic acid (GA) and asiaticoside (AS) by film dispersion-ultrasonication method, which were then incorporated into a GelMA solution and cross-linked by ultraviolet light to form a bioactive composite hydrogel for wound dressings.

This hydrogel is conducive to the transport of nutrients and gas exchange. Compared with GelMA hydrogel (swelling rate 69.8% ± 5.7%), the swelling rate of GelMA/Lip@GA@AS is lower, at 52.1% ± 1.0%. GelMA/Lip@GA@AS also has better compression and rheological properties, and the in vitro biodegradability is not significantly different from that of the collagenase-treated group. In addition, the hydrogel polymer has a stable drug release rate, good biocompatibility, and an angiogenic promoting effect. In vitro experiments prove that, at concentrations of 0.5, 1, 2, and 3 mg/mL, GelMA/Lip@GA@AS can inhibit the growth of Staphylococcus aureus.

We synthesized GelMA/Lip@GA@AS hydrogel and found it possesses advantageous mechanical properties, rheology, and biodegradability. Experimental results in vitro showed that the bioactive hydrogel could efficiently release drugs, exhibit biocompatibility, and enhance angiogenesis and antimicrobial effects. These results suggest the promising application of GelMA/Lip@GA@AS hydrogel in wound-dressing materials.