Preparation of MSNs@Keratin as pH/GSH dual responsive drug delivery system

Designing a drug delivery system that is responsive in a tumor microenvironment is important to potentiate the efficacy and reduce the side effects of antitumor drugs. In this study, the surface of mesoporous silica nanoparticles (MSNs) were aminated with 3-aminopropyl triethoxysilane (APTES) and then coupled with keratin, as a gatekeeper, to afford MSNs-NH2@Keratin. The average sizes and morphologies of MSNs and MSNs-NH2@Keratin were characterized with dynamic light scattering and transmission electron microscopy, respectively. The loading content and encapsulation efficiency of doxorubicin (DOX) were calculated to be 17.1 +/- 1.7% and 71.3 +/- 2.1%. Drug-loaded MSNs-NH2@Keratin exhibited pH and glutathione (GSH) dual responsiveness under tumor microenvironment. The nanoparticles could be uptaken by tumor cells to effectively inhibit tumor cell growth. Moreover, the sizes of nanoparticle were stable in the serum. Collectively, our findings demonstrated the potential of DOX-loaded MSNs-NH2@Keratin in the treatment of cancer.