Abstract:The diblock poly(ε-caprolactone)-b-polyphosphoester (PCL-PEEP) was obtained by ring-opening polymerization (ROP) of 2-ethoxy-2-oxo-1,3,2-dioxaphospholane (EOP) with PCL used as macroinitiator and Sn(Oct)2 as catalyst. Subsequently, the selenium-containing triblock PCL-PEEP-Se-PEEP-PCL was obtained with 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide and 4-dimethylaminopyridine (EDC/DMAP) serving as coupling catalyst and newly prepared dicarboxylic acid di-(3,3’-carboxyl propylene) selenide (Se-DCP) as the coupling agent, the PCL-PEEP-Se-PEEP-PCL micelles were formed by solvent vaporation method. The structure characteristics were confirmed by nuclear magnetic resonance (NMR), fourier transform infrared spectroscopy (FT-IR) and gel permeation chromatography (GPC); the critical micelle concentration (CMC) and oxidative stimuli-response of micelles were determined by fluorescence spectroscopy, 1H NMR, dynamic light scattering (DLS) and transmission electron microscope (TEM); MTT assay was also applied to evaluate the biocompatibility of micelles. The results showed the selenium was successfully introduced into the polymer; The CMC was determined around 0.022mg/mL and the micelles were spherical structure with the diameter about 91nm, the micelles disassembled and the size became irregular in presence of H2O2; MTT assay revealed the micelles had considerable biocompatibility in vivo.