Objective To prepare an amino acid-based deep eutectic gel dressing and study in vitro performance and the in vivo therapeutic effect on oral ulcer. Methods Deep eutectic solvents (DESs) were screened using lysine, proline, arginine, and glycine as hydrogen bond donors, and lactic acid, citric acid, glycerol, mannitol, and malic acid as acceptors, with curcumin solubility identifying the optimal system. Gel dressings were prepared by optimizing the formulation process based on the composite matrix of gelatin methacryloyl/chitosan methacryloyl (GelMA/CSMA) in combination with 3D printing technology. Its mechanical properties, adhesiveness, swelling, and biocompatibility were evaluated, and in vivo efficacy was verified in an SD rat oral ulcer model. Results The optimal DES system (proline-lactic acid, 1:12) increased curcumin solubility over 700-fold (0.789 mg/mL) compared to its solubility in water. The optimal printing formulation and process parameters were as follows: 1% CSMA, 5% GelMA, 0.1% lithium phenyl-2,4,6-trimethylbenzoylphosphinate (LAP), 0.02% tartrazine, 20% DES content, 100 μm layer height, and a layer-by-layer exposure time of 25 s. The obtained amino acid-based gel dressing had excellent mechanical properties, with a 2.5 N adhesion force at 25 min and an approximately 500% swelling ratio at 6 h. In vitro biocompatibility showed that the survival rate of L929 cells was all above 90%, and the DES system had no significant cytotoxicity. It also showed high in vitro biocompatibility (L929 viability > 90%, non-cytotoxic). In vivo, the gel achieved localized, sustained curcumin release in SD oral ulcer model rats, reducing ulcer area by 40% with decreased neutrophil density and inflammatory infiltration. Conclusion Successfully prepared an amino acid-based DES gel dressing loaded with curcumin, which exhibits excellent wound adaptability and precise drug release behavior, offering an efficient and safe therapeutic strategy for oral ulcers.

deep eutectic solvents  /  amino acids  /  curcumin  /  gel dressings  /  oral ulcer