title: Transferrin- and folate-modified, double-targeted nanocarriers for gene delivery.
abstract: BACKGROUND
  Surface modification of nanocarriers with specific ligands defines a new biological identity, which assist in targeting and internalization of the nanocarriers to specific cell populations, such as cancers and disease organs.
  
  
  OBJECTIVE
  This study aimed to develop systemically administrable dual ligands modified nanocarriers, which could target the cells through receptor-mediated pathways to increase the nuclear uptake of genetic materials.
  
  
  METHODS
  In the present work, transferrin (Tf) and folate (Fa) were linked onto polyethylene glycol-phosphatidylethanolamine (PEG-PE) separately to get transferrin-PEG-PE (T-PEG-PE) and folate-PEG-PE (F-PEG-PE) ligands for the surface modification of carriers. The in vivo transfection efficiency of the novel dual ligands modified (D-modified) vectors were evaluated in tumor-bearing animal models.
  
  
  RESULTS
  D-Modified solid lipid nanoparticles/enhanced green fluorescence protein plasmid (D-SLN/pEGFP) has a particle size of 226 nm and a gene-loading quantity of 90%. D-SLN/pEGFP displayed over 30% higher transfection efficiency than unmodified SLN/pEGFP and single ligand modified particles in HepG2 cells.
  
  
  CONCLUSIONS
  It could be concluded that Tf and Fa could function as excellent active targeting ligands to improve the cell-targeting ability of the carriers and the resulting dual ligands modified vectors could be applied as a promising active targeting gene delivery system.
authors.affiliation: Department of Pharmacy, The Affiliated Hospital of Medical College, Qingdao University , Qingdao , China.
authors.forename: Fanbo
authors.initials: F
authors.lastname: Jing
authors.forename: Dongmei
authors.initials: D
authors.lastname: Li
authors.forename: Wen
authors.initials: W
authors.lastname: Xu
authors.forename: Yujun
authors.initials: Y
authors.lastname: Liu
authors.forename: Kai
authors.initials: K
authors.lastname: Wang
authors.forename: Zhongguo
authors.initials: Z
authors.lastname: Sui
mesh_terms: D000818:Animals; D002470:Cell Survival; D004247:DNA / Q000235:genetics; D004337:Drug Carriers / Q000737:chemistry*; D005434:Flow Cytometry; D005492:Folic Acid / Q000737:chemistry*; D018014:Gene Transfer Techniques; D049452:Green Fluorescent Proteins / Q000235:genetics; D056945:Hep G2 Cells; D006801:Humans; D008024:Ligands; D008114:Liver Neoplasms, Experimental / Q000235:genetics / Q000378:metabolism / Q000628:therapy; D008807:Mice, Inbred BALB C; D058990:Molecular Targeted Therapy; D053758:Nanoparticles / Q000737:chemistry*; D010316:Particle Size; D010714:Phosphatidylethanolamines / Q000737:chemistry; D010957:Plasmids; D011092:Polyethylene Glycols / Q000737:chemistry; D011990:Receptors, Transferrin / Q000378:metabolism; D013499:Surface Properties; D014162:Transfection; D014168:Transferrin / Q000737:chemistry*
chemical_list: D004337:Drug Carriers; D008024:Ligands; D010714:Phosphatidylethanolamines; D011990:Receptors, Transferrin; D014168:Transferrin; C485184:enhanced green fluorescent protein; C067972:dioleoyl-N-(monomethoxypolyethylene glycol succinyl)phosphatidylethanolamine; D049452:Green Fluorescent Proteins; D011092:Polyethylene Glycols; D004247:DNA; D005492:Folic Acid