Studies on Loading Doxorubicin and Coumarin by Medical Biocompatible Graft Copolymer

The end of linear m-PEG-OH was functionalized to provide m-PEG-CTA macro-RAFT agent. RAFT homopolymerization of tBHBMA was conducted to give PEG-b-PtBHBMA diblock copolymer, which initiated ROP of lactide directly. The obtained graft copolymer, PEG-b-(PtBA-g-PLA), was then esterified with 7-methoxycoumarin-3- carboxylic acid to afford PEG-b-(PtBA-g-PLA-COU) containing fluorescent dye molecule. PEG-b-(PAA-g-PLA-COU) amphiphilic graft copolymer was prepared by selective hydrolysis of PtBA segment. Finally, doxorubicin (DOX) was loaded into polymeric micelles aggregated by PEG-b-(PAA-g-PLA-COU). The drug loading content (DLC) and size of the obtained polymeric drug micelles containing fluorescent dye molecule was measured by UV-vis and DLS.