Litchi-like supermagnetic hydroxyapatite microspheres with hierarchically mesoporous microspheres

Due to the fact that the conventional bioceramic microspheres lack target function, novel litchi-like porous microspheres composed of a core of CaCO 3 and a tunable magnetic-hydroxyapatite (HA) shell were successfully prepared in this study. Antitumor drug, doxorubicin (DOX), was effectively loaded on the HA microspheres which possess magnetic targeting function. In addition, the HA shell, which had favorable biocompatibility and pH response characteristics, could be used to control release of loaded DOX from the litchi-like superparamagnetic microspheres in a simulated acidic tumor cell environment, effectively killing tumor cells and reducing toxic side effects to normal cells. The smart design presented in this study, which incorporates a tunable superparamagnetic shell and a controlled architecture, allows the sensitive release of drugs for efficient antitumor activity.