title: A potential targeting gene vector based on biotinylated polyethyleneimine/avidin bioconjugates.
abstract: OBJECTIVE
  To improve the gene delivery efficiency and safety of non-viral vector in liver cells, avidin, which exhibited good biocompatibility and remarkable accumulation in liver, was bioconjugated with biotinylated polyethylenimine to obtain a novel gene vector.
  
  
  METHODS
  Biotinylated polyethyleneimine/avidin bioconjugate (ABP) was synthesized through grafting biotin to high molecular weight branched polyethylenimine (PEI, 25 kDa) and then bioconjugating with avidin by the biotin-avidin interaction. Physiochemical characteristics of ABP/pDNA complexes were analyzed, and in vitro cytotoxicity and transfection of ABP were also evaluated in HepG2, Hela and 293 T cells by using 25 kDa PEI as the control.
  
  
  RESULTS
  It was found that ABP was able to condense pDNA efficiently at N/P ratio of 4. The particle sizes of ABP/pDNA complexes were less than 220 nm, and the average surface charges were around 27 mV at the N/P ratio ranging from 2 to 60. Among three different cell lines, ABP and its DNA complexes demonstrated much lower cytotoxicity and higher transfection efficacy in HepG2 cells as compared with 25 kDa PEI.
  
  
  CONCLUSIONS
  ABP presented higher transfection efficacy and safety in HepG2 cells due to the biocompatibility of avidin and the specific interactions between avidin and HepG2 cells.
authors.affiliation: Key Laboratory of Biomedical Polymers of Ministry of Education & Department of Chemistry, Wuhan University, Wuhan, 430072, People's Republic of China.
authors.forename: Xuan
authors.initials: X
authors.lastname: Zeng
authors.forename: Yun-Xia
authors.initials: YX
authors.lastname: Sun
authors.forename: Xian-Zheng
authors.initials: XZ
authors.lastname: Zhang
authors.forename: Si-Xue
authors.initials: SX
authors.lastname: Cheng
authors.forename: Ren-Xi
authors.initials: RX
authors.lastname: Zhuo
mesh_terms: D001360:Avidin / Q000737:chemistry*; D001672:Biocompatible Materials; D001710:Biotin / Q000737:chemistry*; D002460:Cell Line; D018390:Gene Targeting; D005822:Genetic Vectors; D006801:Humans; D009682:Magnetic Resonance Spectroscopy; D018613:Microscopy, Confocal; D008855:Microscopy, Electron, Scanning; D010316:Particle Size; D011094:Polyethyleneimine / Q000737:chemistry*
chemical_list: D001672:Biocompatible Materials; D001360:Avidin; D001710:Biotin; D011094:Polyethyleneimine