Drug-LoadedJanus Dressings Precipitated from PEG–PTMCThermosensitive Hydrogel for Oral Ulcer Treatment

Oral ulcers, prevalent lesions of the oral mucosa, often stem from trauma, viral infections, and autoimmune diseases, necessitating effective treatment strategies to address both their physical and psychological impacts. Current treatments are often limited by issues such as poor adhesion and rapid dilution within the dynamic oral environment. To overcome these challenges, we have explored the application of thermosensitive hydrogels, specifically aqueous solutions of poly(ethylene glycol)–poly(trimethylene carbonate) (PEG–PTMC) copolymers. These copolymers are noted for their biocompatibility and temperature-responsive phase transition properties. We engineered a thermosensitive drug delivery system by fine-tuning the molecular weight and segment lengths of PEG–PTMC, which gels near 32 °C and precipitates at 37 °C. Utilizing the slight temperature differential between the oral mucosa and ambient air, the system forms a Janus structure with distinct gel and precipitate layers, ensuring sustained drug release and enhanced tissue adhesion. This innovative formulation not only acts as a protective, drug-laden dressing that promotes healing but is also designed for ease of use, allowing for self-administration. This study presents a significant advancement in the treatment of oral ulcers, offering a promising solution through the in situ formation of a bilayered, drug-loaded dressing, leveraging the unique properties of thermosensitive hydrogels.