A facile strategy to construct fluorescent pH-sensitive drug delivery vehicle

Aliphatic polyesters have led to significant advancements in drug delivery systems spanning decades owing to their biocompatibility and biodegradability. A series of pH-sensitive aliphatic polyesters were synthesized by facile enzymatic polymerization, which could be post-modified by click chemistry to form multifunctional graft copolymers. Typically, the hydrophilic methoxy polyethylene glycol (mPEG) and fluorescent coumarin were grafted onto the polyester backbone to constitute a multifunctional amphipathic graft copolymer, serving as a trackable pH-responsive drug delivery vehicle. This amphipathic graft copolymer could encapsulate hydrophobic doxorubicin (DOX) via self-assembly in aqueous solutions and performed superior controlled drug release. And the in vitro cellular uptake and cytotoxicity results showed the feasibility of this system for drug delivery application. Collectively, this copolymer offers a potential route of constructing controlled drug delivery system.