[A photothermal/chemotherapy injectable paclitaxel gel with irradiation stability]

The aim of this study is to construct an injectable gel with stable phototherapy and chemotherapy. Res-PTX@IR780 gel with phototherapy and chemotherapy property was prepared by introduction of photosensitizer IR780 and antioxidant resveratrol (Res) into the polyethylene glycol (PEG) solution of paclitaxel (PTX). The results showed that PTX, PTX@IR780 and Res-PTX@IR780 could form gels and the gels were injectable. ATR-FTIR results indicated not only components of the gels but also the formation of hydrogen bonding during the gelation. The results of UV showed instability of IR780 solution and stability improvement of Res-IR780 solution under infrared radiation (IR) irradiation. Photothermal tests showed that Res-PTX@IR780 displayed better photothermal conversion and photothermal stability under multiple irradiations than PTX@IR780. The results of in vivo exploration in mice showed that the skin site injected with Res-PTX@IR780 gel heated up from 35 ℃ to 64 ℃, and the temperature difference was up to 30 ℃. Res-PTX@IR780 gel is very promising as a combination agent of photothermal therapy and chemotherapy for the in situ treatment of tumors due to good photothermal conversion and photothermal stability under multiple irradiations.