title: Synthesis and characterization of N-ethyl-N'-(3-dimethylaminopropyl)-guanidinyl-polyethylenimine polymers and investigation of their capability to deliver DNA and siRNA in mammalian cells.
abstract: Recent advancements in polymeric gene delivery have raised the potential of gene therapy as treatment for various acquired and inherited diseases. Here, we report on the synthesis and characterization of N-ethyl-N'-(3-dimethylaminopropyl)-guanidinyl-polyethylenimine (sGP) polymers and investigation of their capability to carry DNA and siRNA in vitro. Zinc triflate-mediated activation of primary amines of branched polyethylenimine (bPEI) followed by reaction with varying amounts of N-ethyl-N'-(3-dimethylaminopropyl) carbodiimide (EDAC) resulted in the generation of a small series of trisubstituted guanidinyl-modified polyethylenimine polymers. Determination of primary amines on modified polymers by TNBS assay revealed 62-84% of the attempted conjugation of EDAC onto bPEI. These modified polymers were shown to condense plasmid DNA and retard its mobility on 0.8% agarose gel. Further, these polymers were evaluated for their capability to carry pDNA into the cells by performing transfection assay on various mammalian cells. All the modified polymer/pDNA complexes exhibited significantly higher levels of gene expression with one of the complexes, sGP3/pDNA complex, displayed ~1.45 to 3.0 orders of magnitude higher transfection efficiency than that observed in the native bPEI and the commercial transfection reagent, Lipofectamine™. The efficacy of sGP3 polymer was further assessed by siRNA delivery, which resulted in ~81% suppression of the target gene. In conclusion, these studies demonstrate the potential of these substituted guanidinyl-modified PEIs as efficient gene delivery vectors.
authors: Nucleic Acids Research Laboratory, CSIR-Institute of Genomics and Integrative Biology, Delhi University Campus, Delhi, India.
authors: Manohar
authors: M
authors: Mahato
authors: Ashwani K
authors: AK
authors: Sharma
authors: Pradeep
authors: P
authors: Kumar
mesh_terms: D000818:Animals; D016466:CHO Cells; D002470:Cell Survival; D003412:Cricetulus; D004247:DNA / Q000008:administration & dosage / Q000378:metabolism*; D004337:Drug Carriers / Q000138:chemical synthesis* / Q000737:chemistry* / Q000378:metabolism; D006146:Guanidines / Q000138:chemical synthesis* / Q000737:chemistry*; D057809:HEK293 Cells; D006367:HeLa Cells; D006801:Humans; D011094:Polyethyleneimine / Q000031:analogs & derivatives* / Q000138:chemical synthesis / Q000737:chemistry; D011108:Polymers / Q000138:chemical synthesis* / Q000737:chemistry*; D034741:RNA, Small Interfering / Q000008:administration & dosage / Q000378:metabolism*
chemical_list: D004337:Drug Carriers; D006146:Guanidines; C585284:N-ethyl-N'-(3-dimethylaminopropyl)guanidinyl-polyethylenimine; D011108:Polymers; D034741:RNA, Small Interfering; D011094:Polyethyleneimine; D004247:DNA