A dual-responsive drug delivery system based on mesoporous silica nanoparticles covered with zipper-type peptide for intracellular transport/release

The key problem of applying mesoporous silica nanoparticles (MSNs) in drug delivery system DDS is how to block and open the porous channel controllably. In this paper, a thermo/redox dual responsive drug carrier based on MSNs has been prepared through grafting a zipper-type peptide onto MSNs surface using disulfide bond. The peptide, who has specific melting temperature Tm(43.4 °C), acts as a nanovalve for porous channel to block the drug in MSNs. When temperature increases above Tm, the α-helix structure of the peptide could turn to linear state and the nanovalve would be opened for drug release. Meanwhile, disulfide bonds between peptide and MSNs can respond to the stimulation of glutathione. The drug release experiments under different conditions were performed to prove the controllability of drug release by stimulations. And cell experiments have also been done to verify that the nanocarriers had good cytocompatibility and cell recognition. Experiments show that the drug loaded in this carrier is only released inside the tumor cells. The constructed peptide-valved MSNs might provide a special strategy for promising application of MSNs in DDS.