Synergistic effect of sunlight induced photothermal conversion and HO release based on hybridized tungsten oxide gel for cancer inhibition.

A highly efficient photochromic hydrogel was successfully fabricated via casting precursor, which is based on amorphous tungsten oxide and poly (ethylene oxide)-block-poly (propylene oxide)-block-poly (ethylene oxide). Under simulated solar illumination, the hydrogel has a rapid and controlled temperature increasing ratio as its coloration degree. Localized electrons in the amorphous tungsten oxide play a vital role in absorption over a broad range of wavelengths from 400 nm to 1100 nm, encompassing the entire visible light and infrared regions in the solar spectrum. More importantly, the material exhibits sustainable released HO induced by localized electrons, which has a synergistic effect with the rapid surface temperature increase. The amount of HO released by each film can be tuned by the light irradiation, and the film coloration can indicate the degree of oxidative stress. The ability of the HO-releasing gels in vitro study was investigated to induce apoptosis in melanoma tumor cells and NIH 3T3 fibroblasts. The in vivo experimental results indicate that these gels have a greater healing effect than the control in the early stages of tumor formation.