title: PEI-alginate nanocomposites as efficient in vitro gene transfection agents.
abstract: The positive charge on PEI was partially shielded by forming ionic nanocomposites with a polysaccharide, alginic acid, in aqueous solution, bypassing tedious chemical synthesis. The content of alginic acid was varied systematically to obtain a series of nanocomposites. The nanocomposites were first characterized by assessing the surface charge (zeta potential), size (DLS) and morphology (AFM) followed by evaluation for their DNA interaction ability, cytotoxicity and transfection efficiency on various cell lines. The transfection efficiency of PEI-alginate (6.26%) nanocomposites improved dramatically (2-16-fold over native PEI) in all the cell lines studied. However, a decrease in transfection efficiency was observed on deviating from this optimal concentration of alginic acid in nanocomposites. Cytotoxicity of PEI-alginate/DNA complexes was nearly abolished on increasing the concentration of alginic acid in nanocomposites. PEI-alginate (6.26%) nanocomposites also delivered SiRNAs efficiently into mammalian cells, resulting in 80% suppression of GFP expression. The cellular uptake and endosomal escape of PEI-alginate nanocomposites and PEI were found to follow a similar route when transfection was carried out in presence of chloroquine, bafilomycin A1, cytochalasin B and methyl-beta-cyclodextrin. The results demonstrate a versatile vector that can be used for efficient cytoplasmic delivery of a broad range of nucleic acids.
authors.affiliation: Institute of Genomics and Integrative Biology, Mall Road, Delhi University Campus, Delhi-110 007, India.
authors.forename: Soma
authors.initials: S
authors.lastname: Patnaik
authors.forename: Anita
authors.initials: A
authors.lastname: Aggarwal
authors.forename: Surendra
authors.initials: S
authors.lastname: Nimesh
authors.forename: Anita
authors.initials: A
authors.lastname: Goel
authors.forename: Munia
authors.initials: M
authors.lastname: Ganguli
authors.forename: Neeru
authors.initials: N
authors.lastname: Saini
authors.forename: Y
authors.initials: Y
authors.lastname: Singh
authors.forename: K C
authors.initials: KC
authors.lastname: Gupta
mesh_terms: D000464:Alginates / Q000008:administration & dosage*; D000818:Animals; D019556:COS Cells; D002470:Cell Survival / Q000187:drug effects; D002522:Chlorocebus aethiops; D003571:Cytochalasin B / Q000494:pharmacology; D004247:DNA / Q000008:administration & dosage*; D020723:Glucuronic Acid / Q000008:administration & dosage; D006603:Hexuronic Acids / Q000008:administration & dosage; D007097:Imines / Q000008:administration & dosage*; D049329:Nanostructures; D010316:Particle Size; D011095:Polyethylenes / Q000008:administration & dosage*; D034741:RNA, Small Interfering / Q000008:administration & dosage; D014162:Transfection / Q000379:methods*
chemical_list: D000464:Alginates; D006603:Hexuronic Acids; D007097:Imines; D011095:Polyethylenes; D034741:RNA, Small Interfering; C505405:poly(ethylene imine); D003571:Cytochalasin B; D020723:Glucuronic Acid; D004247:DNA