title: Conjugation with betaine: a facile and effective approach to significant improvement of gene delivery properties of PEI.
abstract: Herein, we developed a new gene delivery vector by grafting a betaine monomer (N,N-dimethyl(acrylamidopropyl)ammonium propane sulfonate, DMAAPS) onto 25 KDa polyethylenimine (PEI 25K) via the Michael addition reaction. The graft ratio for betaine on PEI polymer could be readily controlled, and in this study three PEI-betaine conjugates PEI-DMAAPS23%, PEI-DMAAPS55%, and PEI-DMAAPS95% were prepared with their graft ratios of 23, 55, and 95%, respectively. The PEI-betaine conjugates exhibited much lower protein adsorption and cytotoxicities compared with PEI 25K, and they also showed little or no hemolytic effect. Moreover, the PEI-betaine conjugates display satisfactory DNA condensation capability; and in the absence and presence of serum, PEI-DMAAPS23%/pEGFP and PEI-DMAAPS55%/pEGFP complexes exhibited remarkable gene transfection efficiencies determined by flow cytometry, which are in general several times higher than that of PEI 25K. With these favorable properties, the PEI-betaine conjugates hold great potential for use as efficient gene delivery vectors. This study suggests that the betaine monomer may serve as a biocompatible modifying agent and this facile strategy may provide a facile and effective way for constructing some other biocompatible materials.
authors: Department of Biomedical Engineering, College of Materials Science and Engineering, South China University of Technology, Guangzhou 510640, PR China.
authors: Jun
authors: J
authors: Sun
authors: Fang
authors: F
authors: Zeng
authors: Haoliang
authors: H
authors: Jian
authors: Shuizhu
authors: S
authors: Wu
mesh_terms: D000178:Acrylamides / Q000138:chemical synthesis; D001622:Betaine / Q000737:chemistry / Q000494:pharmacology*; D001672:Biocompatible Materials / Q000737:chemistry / Q000494:pharmacology*; D004247:DNA / Q000235:genetics; D004587:Electrophoresis, Agar Gel; D005822:Genetic Vectors; D006367:HeLa Cells; D056945:Hep G2 Cells; D006801:Humans; D009682:Magnetic Resonance Spectroscopy; D010316:Particle Size; D011094:Polyethyleneimine / Q000737:chemistry / Q000494:pharmacology*; D011108:Polymers / Q000737:chemistry / Q000494:pharmacology; D000644:Quaternary Ammonium Compounds / Q000138:chemical synthesis; D013451:Sulfonic Acids / Q000138:chemical synthesis; D014162:Transfection
chemical_list: D000178:Acrylamides; D001672:Biocompatible Materials; D011108:Polymers; D000644:Quaternary Ammonium Compounds; D013451:Sulfonic Acids; D001622:Betaine; D011094:Polyethyleneimine; D004247:DNA