An injectable ionic hydrogel inducing high temperature hyperthermia for microwave tumor ablation

Microwave tumor ablation is of clinical significance and has been considered as a promising cancer minimally invasive therapy. One of the challenges in this field is the optimization of the susceptible agent. Herein, a novel chitosan-based ionic hydrogel which can induce rather high temperature hyperthermia as a susceptible agent for microwave ablation is reported. Owning to the high porosity of the hydrogel, a strong ion confinement effect can be realized, therefore, strong polarization under microwave exposure is ensured for rapid heat generation. In addition, the as-synthesized hydrogel has negligible bio-toxicity and excellent spatial stability in vivo which can guarantee a reproducible therapeutic effect for repeated treatment. In vivo anti-tumor investigation has demonstrated that excellent therapeutic efficiency can be achieved after repeated microwave thermal therapy with a rather low power density (2.0 W, 2.45 GHz). Further, computer simulation was conducted to elucidate the microwave heating mechanism. Our investigation provides a biocompatible and stable agent for microwave tumor ablation and demonstrates its great significance for potential clinical application.