Intracellular pH-operated mechanized mesoporous silica nanoparticles as potential drug carries

A series of pH-operated mechanized mesoporous silica nanoparticles (MMSNs) were fabricated and used as drug delivery for intracellular acid-triggered release. Firstly, adamantine (AD) was anchored on the surface of mesoporous silica nanoparticles (MSNs) by a pH-sensitive intermediate linker. Then, pH-operated MMSNs were prepared by the supramolecular interaction between adamantine (AD) and β-cyclodextrin (β-CD). Doxorubicin (DOX), as a drug model, was loaded into MMSNs. The pH-dependent release behavior of loaded-DOX in vitro revealed that there was only a small amount of loaded-DOX released in PBS solution at pH 7.4, while up to about 90% of loaded-DOX could be quickly released in PBS solution at pH 5.5. Compared with pH-insensitive ones, pH-operated MMSNs displayed a faster drug release behavior and a higher cellular proliferation inhibition efficacy toward tumor cells. These features suggested that pH-operated MMSNs DOX could efficiently load and delivery DOX into tumor cells, leading to an enhanced inhibition of tumor cell proliferation. Therefore, these pH-operated MMSNs will be of advantage as promising carriers for drug acid-triggered release in cancer therapy application.