title: Enhancing polyethylenimine's delivery of plasmid DNA into mammalian cells.
abstract: The effect of various chemical modifications of nitrogen atoms on the efficiency of polyethylenimines (PEIs) as synthetic vectors for the delivery of plasmid DNA into monkey kidney cells in vitro has been systematically investigated. The resultant structure-activity relationship has both provided mechanistic insights and led to PEI derivatives with markedly enhanced performance. For example, N-acylation of PEI with the molecular mass of 25 kDa (PEI25, one of the most potent polycationic gene delivery vectors) with alanine nearly doubles its transfection efficiency in the presence of serum and also lowers its toxicity. Furthermore, dodecylation of primary amino groups of 2-kDa PEI yields a nontoxic polycation whose transfection efficiency in the presence of serum is 400 times higher than the parent's and which exceeds 5-fold even that of PEI25.
authors.affiliation: Department of Chemistry and Division of Biological Engineering, Massachusetts Institute of Technology, Cambridge 02139, USA.
authors.forename: Mini
authors.initials: M
authors.lastname: Thomas
authors.forename: Alexander M
authors.initials: AM
authors.lastname: Klibanov
mesh_terms: D000818:Animals; D019556:COS Cells; D002460:Cell Line; D002522:Chlorocebus aethiops; D005813:Genes, Synthetic; D005822:Genetic Vectors; D007202:Indicators and Reagents; D008322:Mammals; D010957:Plasmids; D011094:Polyethyleneimine; D014162:Transfection / Q000379:methods*
chemical_list: D007202:Indicators and Reagents; D011094:Polyethyleneimine