FIGURE 3.

The synthesis of AgNPs@MnO₂-DOX-Apt and pro-apoptotic mechanism. (A) AgNO₃ aqueous solution is added into the mixed liquor of PEG-600 and PVP, and then AgNPs are synthesized under the conditions of stirring and heating. The AgNPs mixture added with KMnO₄ is sonicated to synthesize AgNPs@MnO₂ core–shell nanostructure for MnO₂-modified AgNPs, and the MnO₂ nanosheets can load DOX via electrostatic interactions and Mn–N co-ordinate bonds. Finally, AgNPs@MnO₂-DOX-Apt is synthesized by functionalizing the Apt onto the MnO₂ nanosheets via the collaborative effects of physisorption and coordinates bonding between the NH2-Apt and MnO₂. (B) AgNPs@MnO₂-DOX-Apt can enter HeLa cells through nucleolin receptor-mediated endocytosis, and release AgNPs and DOX under the response of MnO₂–GSH redox reaction which could induce ROS-mediated apoptosis.