Synthesis and Characterization of ROS-Sensitive Polymeric Micelles

The synthesis of TK linker, TK linker-conjugated polyethylene glycol (PEG-TK), and (PEG)-stearamine (C18) conjugate (PTC) was performed according to our previous publication [15 (link)]. As a control, we also prepared ROS-non-sensitive polymer (PC) by conjugating stearic acid to PEG-AM. Briefly, 200 mg of m-PEG amine was reacted with 160 mg of stearic acid with 160 µl of TEA, 480 mg of EDC, and 290 mg of NHS in 20 ml of DMF at 37 ℃ overnight with stirring under N₂ purging. The sample was then purified by dialysis (MWCO = 12–14 KDa) against DW for one day, followed by freeze-drying. The chemical structures of the synthesized PTC and PC were confirmed using proton nuclear magnetic resonance (¹H NMR) spectroscopy (400 Hz, Bruker: Billerica, MA, USA) in chloroform (CHCl₃). ROS-sensitive PTC and ROS-non-sensitive PC empty micelles were prepared by the self-assembly of PTC and PC under sonication and dialysis.