Veron Laurent, Ganée Arnaud, Charreyre Marie-Thérèse, Pichot Christian, Delair Thierry
Unité Mixte CNRS-bioMérieux, UMR 2142, ENS-Lyon, 46 allée d'Italie, 69364 Lyon Cedex 07, France.
Macromol Biosci. 2004 Apr 19;4(4):431-44. doi: 10.1002/mabi.200300064.
Here we want to report the synthesis and the characterization of 2-methylacrylic acid 2-(3-imidazol-1-yl-propionyloxy)ethyl ester (IPEMA), a new methacrylate derivative monomer bearing an hydrolyzable side chain terminated by an imidazole group. The kp/kt(1/2) value for its homopolymerization in N,N-dimethylformamide at 60 degrees C was found to be 0.120 mol(-1/2) x L(1/2) x s(-1/2). The free radical copolymerization of N,N-dimethylaminoethyl methacrylate and this monomer was studied in N,N-dimethylformamide at 60 degrees C, the reactivity ratios of this couple of monomers were determined to be r(DMAEMA) = 1.13 +/- 0.09 and r(IPEMA) = 0.82 +/- 0.09 (using distinct calculation methods). Molecular weights analysis, parallely with refractive index increments measurements, were performed to characterize the obtained polymers. Potentiometric titrations showed the ability of these copolymers to act as a 'proton sponge'. Preliminary study of the copolymers hydrolysis proved that imidazole units could be slowly cleaved from the polymer backbone at 37 degrees C in neutral aqueous buffer. Agarose gel electrophoresis of plasmid DNA/polymer complexes demonstrated the DNA complexing properties of these imidazole-based copolymers.
在此，我们报道2-甲基丙烯酸2-(3-咪唑-1-基-丙酰氧基)乙酯（IPEMA）的合成与表征，它是一种新型的甲基丙烯酸酯衍生物单体，带有一个由咪唑基团终止的可水解侧链。发现在60℃下其在N，N-二甲基甲酰胺中进行均聚反应时的kp/kt(1/2)值为0.120 mol(-1/2)×L(1/2)×s(-1/2)。在60℃下于N，N-二甲基甲酰胺中研究了甲基丙烯酸N，N-二甲基氨基乙酯与该单体的自由基共聚反应，通过不同计算方法确定这对单体的竞聚率为r(DMAEMA)=1.13±0.09和r(IPEMA)=0.82±0.09。进行分子量分析以及同时进行折光率增量测量以表征所得到的聚合物。电位滴定表明这些共聚物具有充当“质子海绵”的能力。对共聚物水解的初步研究证明，在37℃的中性水性缓冲液中，咪唑单元可从聚合物主链上缓慢裂解。质粒DNA/聚合物复合物的琼脂糖凝胶电泳证明了这些基于咪唑的共聚物的DNA络合特性。
