Abstract:Polymer micelles with pH/ reduction responses have become important drug carriers for cancer treatment. The poly(ε-caprolactone)-poly(N,N- diethylaminoethylmethacrylate)-disulfide-poly(2-methacryloyoxyethyl phosphorylcho line) (PCL-PDEA-SS-PMPC) were designed and synthesized. The structures of the polymers were characterized by 1H-NMR, FT-IR and EA, and the thermodynamic analysis of the polymers was performed by differential scanning calorimetry. The structures and properties of micelles were investigated by experiments of transmission electron microscopy, pH response, reduction response, drug loading, drug release, cytotoxicity and hemolysis tests. The experimental results show that the drug release, cytotoxicity, and hemolytic is related to the number of N,N-diethylaminoethyl methacrylate (DEA) units. For the three copolymers, the PCL20-PDEA5-ss-PMPC12 micelle has no cytotoxicity or hemolysis, which meet the property requirements as drug carrier. Therefore, the relationship between polymer composition and carrier performance should be carefully investigated where taking the pH/reduction double-sensitive polymer micelles as drug carrier.