Preparation of a microwave-responsive hollow-mesoporous Fe3O4/nGO composite for on-demand controllable drug release

A novel hollow mesoporous Fe3O4/nGO composite (HMFG) as a multifunctional drug carrier was prepared for the first time via a solvothermal reaction. This composite was formed from nano-graphene oxide (nGO) embedding into Fe3O4 microspheres and has a simple composition but can exhibit multifunctional features. The results show that HMFG is monodisperse microspheres with a diameter of 320 nm, has a high magnetization saturation value for drug targeting and its hollow mesoporous structure endows the composite with a larger surface area (57.35 m2 g−1). Most importantly, in this system, the introduction of nGO can greatly improve the microwave thermal transfer and microwave-triggered drug release performances of HMFG. The microwave transfer experiment showed that HMFG2–5 has the best microwave thermal conversion performance, having the highest temperature after 90 s, reaching 52 °C. Doxorubicin hydrochloride (DOX) as an anti-cancer model drug was used for drug loading and release experiments. The drug loading percentage was 100% after 40 min and within 110 min, the drug release percentage was as high as 86.7% under microwave radiation. The test results proved that the HMFG we prepared is a potential drug carrier for highly efficient microwave-triggered controlled drug release.