Scheme 1

Schematic illustration of the synthesis of Apt-NS, Apt-NS-DOX, and the antitumor effects. A Preparation scheme of Apt-NS using three single-strand DNA, including S6 (aptamer), PP (palindrome probe), and Linker. B Drug loading process of Apt-NS for the formation of Apt-NS-DOX. C After intravenous injection, Apt-NS-DOX was specifically internalized into tumor cells, and then released its cargo (DOX) by lysosomal catabolism. The DOX could enter into the nucleus and induce DNA damage leading to cell apoptosis