Poly(ethylene glycol)/poly(ethyl cyanoacrylate) amphiphilic triblock copolymer nanoparticles as delivery vehicles for dexamethasone

Amphiphilic triblock copolymers, poly(ethyl cyanoacrylate)‐ b ‐poly(ethylene glycol)‐ b ‐poly(ethyl cyanoacrylate) (PECA‐ b ‐PEG‐ b ‐PECA), were synthesized via oxyanion‐initiated polymerization with sodium alcoholate‐terminated PEG as macroinitiator. PECA‐ b ‐PEG‐ b ‐PECA were characterized by gel permeation chromatography system, 1 H NMR and FTIR. The results indicate that the copolymerization is well controlled with narrow molecular weight distribution. The dexamethasone (DXM)‐loaded PECA‐ b ‐PEG‐ b ‐PECA nanoparticles (NPs) were prepared by nanoprecipitation technique and then characterized by Laser Particle Size Analyzer, 1 H NMR and transmission electron microscopy. The drug‐loaded PECA‐ b ‐PEG‐ b ‐PECA NPs are of spherical shape with average size of less than 100 nm. The drug‐loaded amount (DLA) and encapsulation efficiency of DLNPs were investigated by HPLC. The results show that DXM can be effectively incorporated into PECA‐ b ‐PEG‐ b ‐PECA NPs, which provides an optional delivery system for DXM and other hydrophobic drugs.