PLGA-PEG-PLGA is an amphiphilic triblock copolymer consisting of a hydrophilic block polyethylene glycol (PEG) or polyethylene oxide (PEO) and a hydrophobic block poly(lactide-co-glycolide) (PLGA). The PEG polymer is capped a methyl ether group, and the hydrophobic block terminates with a hydroxyl group. PEGylated copolymers with biodegradable and biocompatible polyester segments can be used to prepare core-shell micelles, nanoparticles and microspheres. The hydrolytic degradability of polyester segments depend on the molecular weight and the spacer between ester groups (lactide, glycolide or caprolactone).
PEG-PLGA can be dissolved in a range of common organic solvents depending on its composition especially the L to G ratio and the total PLGA MW. As the MW goes up and the content of G goes up, its solubility gets poor in common organic solvent. Typically PEG-PLGA at lower MW or greater L content can be dissolved in chlorinated solvents, such as dichloromethane or chloroform much easier, and sometimes in water-miscible solvents, like acetone, acetonitrile and THF depending on the total MW. PEG-PLGA with a higher amount of G is better dissolved by fluorinated solvents, like hexafluoroisopropanol. PEG-PLGA with other MWs is also offered.