Thermal-grinding supramolecular network loaded with paeonol for treatment of skin eczema

Lipophilic drugs loaded into hydrogel vehicles for controlled release often encounters drawbacks such as low loading capacity, tedious inclusion methods and invalidity caused by syneresis. Facing this issue, we proposed a non-solvent drug loading system, thermal-grinding supramolecular network (TGSN), in which the monomer, crosslinker and drug molecules in solid state were grinded and then subjected to melting gelation. Paeonol, with a poor water solubility of 0.54 mg/mL, was chosen as a model drug. Both organosulfur-based polymeric network and paeonol aggregates constituted the main structure of TGSNs. Thus, the network had special properties such as stretchability, anti-swelling, elasticity, antibacterial activity, surface hydrophilicity, self-healing and adhesion. In vitro cellular toxicity assay demonstrated that TGSN improved L929 cell proliferation with minimal cytotoxicity. Viewed by transdermal release assay, TGSN could achieve sustained release of paeonol. Proved by skin eczema model in Kunming mice, TGSN possessed an excellent therapeutic effect and a low recurrence probability.