10.1021/acsabm.9b00036.s001 Parthiban Venkatesan Parthiban Venkatesan Natesan Thirumalaivasan Natesan Thirumalaivasan Hsiu-Ping Yu Hsiu-Ping Yu Ping-Shan Lai Ping-Shan Lai Shu-Pao Wu Shu-Pao Wu Redox Stimuli Delivery Vehicle Based on Transferrin-Capped MSNPs for Targeted Drug Delivery in Cancer Therapy American Chemical Society 2019 GSH Conventional antitumor drugs TUNEL FT-IR side effects cancer cells HT BET Cancer Therapy Cancer Targeted Drug Delivery Redox Stimuli Delivery Vehicle tumor cells MCF -7 cells drug delivery platforms DOX PEG TEM MSNP glutathione-triggered intracellular drug release NMR BJH TGA cancer cells need 2019-03-08 00:00:00 Journal contribution https://acs.figshare.com/articles/journal_contribution/Redox_Stimuli_Delivery_Vehicle_Based_on_Transferrin-Capped_MSNPs_for_Targeted_Drug_Delivery_in_Cancer_Therapy/7882454 Cancer has become one of the major diseases of human health around the world. Conventional antitumor drugs cannot specifically target cancers and result in serious side effects. To achieve better therapy, innovative functional drug delivery platforms that will aid specific targeting for cancer cells need to be developed. In this study, transferrin (Tf), which can target cancer cells, is covalently anchored onto the surface of MSNPs via disulfide linkage, which is used for glutathione-triggered intracellular drug release in tumor cells. The successful functionalization of redox-responsive MSNPs is confirmed by using BET/BJH, TEM, TGA, NMR, and FT-IR (BET, Brunauer–Emmett–Teller; BJH, Barrett–Joyner–Halenda). In addition, polyethylene glycol (PEG) is further grafted onto the surface of MSNPs to improve the biocompatibility and stability under physiological conditions for longer blood circulation. Our <i>in vitro</i> studies demonstrate that DOX-loaded MSNP–SS–Tf@PEG can selectively be internalized into cancer cells via Tf/Tf receptor interactions, and then, DOX is released in HT-29 and MCF-7 cells triggered by high GSH concentration in tumor cells. Remarkably, <i>in vivo</i> studies demonstrate that DOX-loaded MSNP–SS–Tf@PEG can significantly inhibit tumor growth with minimized side effects through cell apoptosis determined by TUNEL assay, whereas MSNP–SS–Tf@PEG revealed no significant inhibition. In conclusion, DOX–MSNP–SS–Tf@PEG with active targeting moieties and a redox-responsive strategy has been demonstrated as a great effective drug carrier for tumor therapy <i>in vitro</i> and <i>in vivo</i>.