title: Temperature-controlled properties of DNA complexes with poly(ethylenimine)-graft-poly(N-isopropylacrylamide).
abstract: End-functionalized poly(N-isopropylacrylamide) (PNIPA) was synthesized by living free radical polymerization and conventional free radical polymerization and was used to prepare graft copolymers with poly(ethylenimine) (PEI). The copolymers exhibited lower critical solution temperature (LCST) behavior between 30 and 32 degrees C and formed complexes with plasmid DNA. The LCST of the copolymers in the DNA complexes increased slightly to approximately 34-35 degrees C. Cytotoxicity of the copolymers was evaluated by measuring lactate dehydrogenase (LDH) release from cells. The copolymers exhibited temperature-dependent toxicity, with higher levels of LDH release observed at temperatures above the LCST. Cellular uptake and transfection activity of the DNA complexes with the PEI-g-PNIPA copolymers were lower than those of the control PEI/DNA complexes at temperature below the LCST but increased to the PEI/DNA levels at temperatures above the LCST.
authors.affiliation: Department of Pharmaceutical Sciences, Wayne State University, Detroit, Michigan 48202, USA.
authors.forename: Harender S
authors.initials: HS
authors.lastname: Bisht
authors.forename: Devika Soundara
authors.initials: DS
authors.lastname: Manickam
authors.forename: Yezi
authors.initials: Y
authors.lastname: You
authors.forename: David
authors.initials: D
authors.lastname: Oupicky
mesh_terms: D000180:Acrylic Resins / Q000138:chemical synthesis / Q000737:chemistry* / Q000494:pharmacology; D000818:Animals; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D004247:DNA / Q000737:chemistry*; D015971:Gene Expression Regulation, Enzymologic / Q000187:drug effects; D049452:Green Fluorescent Proteins / Q000187:drug effects / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D066298:In Vitro Techniques; D007770:L-Lactate Dehydrogenase / Q000737:chemistry / Q000378:metabolism; D008156:Luciferases / Q000187:drug effects / Q000235:genetics / Q000378:metabolism; D051379:Mice; D015394:Molecular Structure; D013696:Temperature; D013997:Time Factors
chemical_list: D000180:Acrylic Resins; C511369:poly(ethylenimine)-graft-poly(N-isopropylacrylamide); D049452:Green Fluorescent Proteins; D004247:DNA; D007770:L-Lactate Dehydrogenase; D008156:Luciferases