Preparation of dextran–poly(lactide)–1,2-dipalmitoyl-sn-glycero-3-phosphoethanolamine copolymer and its micellar characteristics

A novel amphiphilic copolymer based on dextran, poly(lactide) (PLA) and 1,2-dipalmitoyl-sn-glycero-3-phosphoethanolamine (DPPE) was synthesized and characterized by FT-IR, 1H NMR, 13C NMR and 31P NMR spectra. Their molecular weights were determined by gel permeation chromatography (GPC). The molecular weights range from 30 000 g mol−1 to 37 000 g mol−1 with a feed weight ratio of 20:1–50:1 (DPPE/activated dextran–PLA). Its micellar characteristics were investigated using fluorescence technique, transmission electron microscopy (TEM) and dynamic light scattering (DLS). It was found that dextran–PLA–DPPE copolymer could form spherical micelles. The micelle diameters ranged from 85 to 120 nm with a feed weight ratio of 20:1–50:1 (DPPE/activated dextran–PLA) in the absence of surfactant.