title: Thermoresponsive gene carriers based on polyethylenimine-graft-poly[oligo(ethylene glycol) methacrylate].
abstract: A family of thermoresponsive cationic copolymers (TCPs) that contain branched PEI 25 K as the cationic segment and poly(MEO(2)MA-co-OEGMA(475)) as the thermosensitive block (TP) is prepared. The DNA binding capability, physicochemical properties, and biological performance of the TCPs are studied. All of these TCPs can condense DNA to form polyplexes with diameters of 150-300 nm and zeta potentials of 7-32 mV at N/P ratios between 12 and 36. The length of TP block is a key factor for shielding the positive surface charge of the polyplexes and protecting them against protein adsorption. TCPs with a higher TP content have a lower cytotoxicity while the best transfection performance is achieved by the TCPs with longest TP length, reaching a level of the intact PEI 25 K in the presence of serum.
authors.affiliation: Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China.
authors.forename: Rui
authors.initials: R
authors.lastname: Zhang
authors.forename: Yang
authors.initials: Y
authors.lastname: Wang
authors.forename: Fu-Sheng
authors.initials: FS
authors.lastname: Du
authors.forename: Ying-Li
authors.initials: YL
authors.lastname: Wang
authors.forename: Ying-Xia
authors.initials: YX
authors.lastname: Tan
authors.forename: Shou-Ping
authors.initials: SP
authors.lastname: Ji
authors.forename: Zi-Chen
authors.initials: ZC
authors.lastname: Li
mesh_terms: D000818:Animals; D019556:COS Cells; D002412:Cations; D016923:Cell Death; D002470:Cell Survival; D002522:Chlorocebus aethiops; D004247:DNA / Q000378:metabolism; D004587:Electrophoresis, Agar Gel; D004996:Ethidium / Q000378:metabolism; D018014:Gene Transfer Techniques; D008156:Luciferases / Q000378:metabolism; D009682:Magnetic Resonance Spectroscopy; D010316:Particle Size; D011092:Polyethylene Glycols / Q000138:chemical synthesis / Q000737:chemistry*; D011094:Polyethyleneimine / Q000031:analogs & derivatives* / Q000138:chemical synthesis / Q000737:chemistry; D011109:Polymethacrylic Acids / Q000138:chemical synthesis / Q000737:chemistry*; D017550:Spectroscopy, Fourier Transform Infrared; D013696:Temperature; D014162:Transfection
chemical_list: D002412:Cations; D011109:Polymethacrylic Acids; D011092:Polyethylene Glycols; D011094:Polyethyleneimine; D004247:DNA; D008156:Luciferases; D004996:Ethidium