title: Linear PEI nanoparticles: efficient pDNA/siRNA carriers in vitro and in vivo.
abstract: Linear polyethylenimine (lPEI, 25 kDa) nanoparticles' (LPN) series was synthesized by varying percentage of cross-linking with 1,4-butanediol diglycidyl ether (BDE) and their size, surface charge, morphology, pDNA protection/release, cytotoxicity and transfection efficiency were evaluated. Synthesized nanoparticles (NPs) were spherical in shape (size: ∼109 - 235 nm; zeta potential: +38 to +16 mV). These NPs showed increased buffering capacity with increasing percent cross-linking and also exhibited excellent transfection efficiency (i.e., ∼1.3 - 14.7 folds in case of LPN-5) in comparison with lPEI and the commercial transfection agents used in this study. LPN-5 based GFP-specific siRNA delivery resulted in ∼86% suppression of targeted gene expression. These particles were relatively nontoxic in vitro (in cell lines) and in vivo (in Drosophila). In vivo gene expression studies using LPN-5 in Balb/c mice through intravenous injection showed maximum expression of the reporter gene in the spleen. These results together demonstrate the potential of these particles as efficient transfection reagents.
  
  
  BACKGROUND
  The authors demonstrate a novel method of synthesizing linear PEI nanoparticles to utilize these as transfection agents.
authors.affiliation: CSIR-Institute of Genomics and Integrative Biology, Delhi University, Delhi, India.
authors.forename: Ritu
authors.initials: R
authors.lastname: Goyal
authors.forename: Sushil K
authors.initials: SK
authors.lastname: Tripathi
authors.forename: Shilpa
authors.initials: S
authors.lastname: Tyagi
authors.forename: Anurag
authors.initials: A
authors.lastname: Sharma
authors.forename: K Ravi
authors.initials: KR
authors.lastname: Ram
authors.forename: Debapratim K
authors.initials: DK
authors.lastname: Chowdhuri
authors.forename: Yogeshwar
authors.initials: Y
authors.lastname: Shukla
authors.forename: P
authors.initials: P
authors.lastname: Kumar
authors.forename: Kailash C
authors.initials: KC
authors.lastname: Gupta
mesh_terms: D000818:Animals; D002072:Butylene Glycols / Q000737:chemistry / Q000494:pharmacology*; D004247:DNA / Q000737:chemistry / Q000235:genetics; D004330:Drosophila; D004337:Drug Carriers; D015870:Gene Expression / Q000187:drug effects; D006801:Humans; D051379:Mice; D008807:Mice, Inbred BALB C; D053758:Nanoparticles / Q000009:adverse effects* / Q000737:chemistry / Q000627:therapeutic use; D011094:Polyethyleneimine / Q000737:chemistry / Q000494:pharmacology*; D034741:RNA, Small Interfering / Q000235:genetics / Q000378:metabolism; D014162:Transfection / Q000379:methods*
chemical_list: D002072:Butylene Glycols; D004337:Drug Carriers; D034741:RNA, Small Interfering; D011094:Polyethyleneimine; D004247:DNA; C014376:1,4-bis(2,3-epoxypropoxy)butane