An effective thermal therapy against cancer using an E-jet 3D-printing method to prepare implantable magnetocaloric mats

Magnetic hyperthermia has been rapidly developed as a potential cancer treatment in recent years. Artificially induced hyperthermia close to a tumor can raise the temperature to 45°C causing tumor cell death. Herein, we introduce a novel method for rapid preparation of anti-cancer magnetocaloric PCL/Fe O mats capable of high-performance hyperthermia using E-jet 3D printing technology. Our 3D printed mats not only maintained the heating efficiency of traditional techniques for magnetic hyperthermia but also prolonged the effective therapy in vivo. When Fe O nanoparticles (NPs) were used in mats at a concentration of 6 mmol/L, 0.07 g PCL/Fe O mats were able to increase the temperature peripherally to 45°C under an alternating magnetic field (AMF) within 45 min. Moreover, the reproducibility experiment indicated that the maximum temperature was achieved following repeated heating and cooling cycles. Cell toxicity tests showed a high cell death rate during one treatment cycle. In vivo experiments indicated clear signs of tumor growth inhibitory and prolonged survival time of tumor-bearing mice after 4 weeks of treatment. The present magnetic mats may be a potential candidate for a novel heat-generating substrate for localized hyperthermia cancer therapy. Furthermore, the main advantage of such implantable magnetic mats is the local and precise delivery of Fe O NPs, ideal for the hyperthermia treatment of easily accessible tumors. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 106B: 1827-1841, 2018.