Novel biomimetic hyperbranched copolymers that synthesized by polymerization of zwitterionic monomer (CBB) on the surface of a hyperbranched poly(3-ethyl-3-(hydroxymethyl)oxetane) (HBPO) core and used as a drug delivery carrier have been investigated by analysis of protein-adsorption-resistance, cytotoxicity and cell type-specific targeting properties. The as-synthesized biomimetic hyperbranched copolymers showed low toxicity, favorable protein resistant properties and were ultrastable in 100% fetal bovine serum. Folic acid and rodiamin-B were conjugated to the surface of synthesized micelles to endow it with target drug delivery and fluorescence activity, respectively. Intracellular uptake and in vitro cytotoxicity of HBPO-poly(carboxybetaine) micelles were investigated. Doxorubicin was used as a model drug for Hela cells during the experiment. All results show that the biomimetic hyperbranched copolymer is a candidate carrier for target drug delivery. (c) 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013