Effects of different pore structures on loading and sustained-release of mitomycin C by hollow mesoporous Fe(0)@mSiO2

摘要

Abstract Herein, we developed the dual-function template method to fabricate hollow magnetic nano-spheres (denoted as HMFe–Si–Cn, n?=?16, 18) with a mesoporous shell and hollow interior structure using alkyl chain trimethoxysilane templating. The shorter chain template directed formation of HMFe–Si–C16 with size of 119?nm, having disordered inkbottle type mesopores and saturation magnetization of 50.01?emu/g higher than that of HMFe–Si–C18 with cylindrical type mesopores. In addition, the HMFe–Cn loaded with MMC diaplays a pH and magnetic dual responsive drug release behavior. By contrast, Mitomycin C (MMC) loading efficiency of HMFe–Si–C16 was higher owing to the fact that the pore size, surface area, and pore volume of HMFe–Si–C16 were larger than those of HMFe–Si–C18. Besides, MMC loaded HMFe–Si–Cn hollow spheres showed a clear pH-dependent drug release behavior, having a higher release rate in acidic environments of pH 5.7. For the pH 5.7 and 7.4 release, the release kinetic for HMFe–Si–C16–MMC composites follows pseudo-first-order attributable to its special pore structure. With Fe(0) as a core, HMFe–Si–Cn is distinguished for higher magnetic properties, and it is more conducive to magnetic targeted treatment of cancer cells and can release drugs through external magnetic field. In addition, HMFe–Si–Cn has lower cytotoxicity and better biocompatibility. For this reason the inner cavity of HMFe–Si–C16 could be labeled with radioisotope 99Tcm to study the magnetic targeting distribution of HMFe–Si–C16 in vivo, and its cytotoxicity against in vitro HeLa cells was also studied. These results indicate the potential of HMFe–Si–C16 in the magnetic targeted drug delivery system.