Synthesis and characterization of poly(ethylene glycol)/poly(trimethylene carbonate) ab₂ miktoarm copolymers for anticancer drug delivery

In this study, a series of amphiphilic phospholipid structure-mimetic AB₂ miktoarm copolymers consisting of hydrophilic poly(ethylene glycol) (PEG) and biodegradable poly(trimethylene carbonate) (PTMC) were synthesized and compared with typical linear di-block copolymers in terms of self-assembling and drug carrier properties. All the synthesized polymers were characterized by ¹H NMR, FTIR, GPC and DLS measurements to confirm their chemical structures and found to self-assemble in aqueous media to form spherical micelle structures with about 40-70 nm in diameter. A poorly soluble drug, paclitaxel, as a model drug was loaded into polymer micelles by a solid dispersion method and the drug loading efficiency and content was significantly dependent on the loading conditions and the polymer structures. In particular, the miktoarm polymers demonstrated better drug-loading capacity and colloidal stability than the corresponding di-block copolymers, increasing their potential for drug delivery applications.