• Aifei Wang Aifei Wang
  • Mingyi Guo Mingyi Guo
  • Nan Wang Nan Wang
  • Jianyun Zhao Jianyun Zhao
  • Wenxiu Qi Wenxiu Qi
  • Faheem Muhammad Faheem Muhammad
  • Liang Chen Liang Chen
  • Yingjie Guo Yingjie Guo
  • Nam-Trung Nguyen Nam-Trung Nguyen
  • Guangshan Zhu Guangshan Zhu

Manganese oxide (Mn3O4) noparticles have recently emerged as a promising T1 contrast agent. In this study, for the first time, we demonstrated an interaction of Mn3O4 with a biological system, and found redox sensitive behavior of these paramagnetic noparticles in intracellular reducing environment. Inspired by these findings, we for the first time used this interaction for some therapeutic advantages and designed a versatile mesoporous silica based notheranostic system to realize redox-activated enhanced magnetic resonce imaging and responsive anticancer drug delivery. Contrary to previous reports, we firstly prepared high quality amine termited hydrophilic Mn3O4 nolids, without using multistep ligand exchange strategies. The resulting water stable and small-sized Mn3O4 nolids were subsequently used as nolids to cap drug loaded nochannels of a porous carrier. Exposure to highly prevalent intracellular reducing environment resulted in the steady-state dissolution of these nolids and attained an intelligent drug release. Furthermore, the redox receptive dissolution of paramagnetic Mn3O4 nolids into Mn2+ in turn increases the T1 sigl to twofold, providing an added opportunity to even track the feedback of therapy. This study, in addition to simultaneously realizing drug delivery and imaging, also provides a new insight into the fate and interaction of manganese oxide noparticles with components of biological systems.