title: pH-triggered reversible "stealth" polycationic micelles.
abstract: Amphiphilic polycations with a "stealth" cationic nature have been designed and synthesized by the PEGylation of polycationic amphiphile via a novel pH responsible benzoic imine linker. The linkage is stable in aqueous solution at physiological pH but cleaves in slight acidic conditions such as the extracellular environment of solid tumor and endosomes. The polymeric micelle formed from the amphiphilic "stealth" polycation contains a pH-switchable cationic surface driven by the reversible detachment/reattachment of the shielding PEG chains due to the cleavage/formation process of the imine linkage. At physiological pH, the micellar surface was shielded by the PEG corona, leading to lower cytotoxicity and less hemolysis, whereas in a mild acidic condition like in endosomes or solid tumors, the deshielding of the PEG chains exposed the positive charge on the micellar surface and retained the membrane disrupting ability. The amphiphilic "stealth" polycation is potentially useful as a drug targeting system toward tumors via endocytosis and trafficked through the endosomal pathway.
authors: State Key Laboratory of Polymer Physics and Chemistry, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100080, China.
authors: Jingxia
authors: J
authors: Gu
authors: Woei-Ping
authors: WP
authors: Cheng
authors: Jiguang
authors: J
authors: Liu
authors: Sum-Yee
authors: SY
authors: Lo
authors: David
authors: D
authors: Smith
authors: Xiaozhong
authors: X
authors: Qu
authors: Zhenzhong
authors: Z
authors: Yang
mesh_terms: D002412:Cations; D006863:Hydrogen-Ion Concentration; D008823:Micelles; D011092:Polyethylene Glycols / Q000737:chemistry
chemical_list: D002412:Cations; D008823:Micelles; D011092:Polyethylene Glycols