Injectable and Thermosensitive Liposomal Hydrogels for NIR-II Light-Triggered Photothermal-Chemo Therapy of Pancreatic Cancer

An injectable hydrogel sustained drug release system could be a promising technique for in situ treatment. Herein, an injectable hydrogel was prepared for photothermal-chemo therapy of cancer based on the thermosensitive liposomal hydrogel (Lip-Gel). The Lip-Gel system was fabricated by encapsulation of the NIR-II photothermal agent (DPP–BTz) and chemotherapy drugs (GEM) in thermosensitive liposomes and then combined with hydrogel precursor solution. The hydrogel precursor was used as an injectable flowing solution at room temperature and transferred into a cross-linked gel structure at physiological temperature. After being injected into the tumor, DPP–BTz in the Lip-Gel system can generate heat under irradiation of 1064 nm laser, breaking the thermosensitive liposomes and releasing GEM to kill tumor cells. From the treatment results, the Lip-Gel system showed a significant antitumor effect through chemo-/photothermal therapy combination therapy triggered by the NIR-II laser. This work provides a useful scheme for the development of drug delivery and drug treatment directions for local cancer therapy.