title: Charge shielding effects on gene delivery of polyethylenimine/DNA complexes: PEGylation and phospholipid coating.
abstract: Polyethylenimine (PEI) is an efficient cationic polymer for gene delivery, but defective in biocompatibility. In this study, we developed two different strategies to shield the positively charged PEI/DNA complexes: PEGylation and lipid coating. The physicochemical properties, cytotoxicity and transfection efficiency of the two gene delivery systems were investigated. Both PEGylation and lipid coating succeeded in reducing the zeta-potential of the complexes. Lipid-coated PEI/DNA complexes (LPD complexes) and PEI/DNA complexes exhibited similar cytotoxicity, whereas PEG-PEI/DNA complexes showed lower cytotoxicity, especially at high N/P ratios. LPD complexes were less efficient in transfection compared to PEG-PEI/DNA complexes. The transfection efficiency was influenced remarkably by cytotoxicity and surface charge of the complexes. Intracellular processes studies revealed that endosomal release might be one of the rate-limiting steps in cell transfection with PEI as a gene delivery carrier.
authors.affiliation: School of Pharmaceutical Sciences, Sun Yat-Sen University, Guangzhou, 510006, China.
authors.forename: Xin
authors.initials: X
authors.lastname: Luo
authors.forename: Min
authors.initials: M
authors.lastname: Feng
authors.forename: Shirong
authors.initials: S
authors.lastname: Pan
authors.forename: Yuting
authors.initials: Y
authors.lastname: Wen
authors.forename: Wei
authors.initials: W
authors.lastname: Zhang
authors.forename: Chuanbin
authors.initials: C
authors.lastname: Wu
mesh_terms: D004247:DNA / Q000008:administration & dosage*; D018014:Gene Transfer Techniques; D006367:HeLa Cells; D006801:Humans; D008856:Microscopy, Fluorescence; D010316:Particle Size; D010743:Phospholipids / Q000737:chemistry*; D011092:Polyethylene Glycols / Q000737:chemistry*; D011094:Polyethyleneimine / Q000008:administration & dosage*
chemical_list: D010743:Phospholipids; D011092:Polyethylene Glycols; D011094:Polyethyleneimine; D004247:DNA