以7μm单分散交联聚甲基丙烯酸环氧丙酯树脂表面键合溴异丁酰溴为引发剂,以CuCl/CuCl2/22-联二吡啶(Bpy)为催化体系,采用封闭体系,在氮气保护下,以乙烯基苯磺酸钠(NaSS)为单体、NN-二甲基甲酰胺(DMF)水溶液为溶剂,制备了强阳离子交换色谱(SCX)固定相,并用元素分析与红外光谱法对其进行了表征。通过改变催化剂、配体与单体的配比制备了3种不同键合量的强阳离子交换色谱固定相,详细考察了3种不同键合量的填料对标准蛋白质的分离性能、pH对标准蛋白保留的影响和动态吸附容量。在催化剂、配体与单体的摩尔比为1∶5∶100时,测得动态吸附容量高达46.5 mg/g。实验结果表明,流速为1.0 mL/min时4种蛋白可在10 min内达到基线分离,随着单体键合量的增加,填料对蛋白的保留时间逐渐增加,蛋白质的保留符合阳离子交换色谱规律。
A novel stationary phase for strong cation exchange chromatography was prepared by "grafting from" strategy.Atom transfer radical polymerization(ATRP) of sodium 4-vinylbenzenesulfonate(NaSS) was conducted in N,N-dimethylformamide(DMF) solution at room temperature,which was synthesized by the chemical modification of 7 μm monodisperse PGMA/EDMA beads as initiator,CuCl/CuCl2/Bpy as catalyst system,under a nitrogen atmosphere with a closed system.The amounts of NaSS grafted chains with different ATRP formulations were calculated based on the elemental analysis.The effects of the NaSS grafted chain lengths on PGMA/EDMA beads for the separation of proteins,adsorption capacity,pH of mobile phase on the protein retention were investigated in details.Under the condition of catalyst ∶ ligand ∶ monomer with mole ratio of 1 ∶ 5 ∶ 100,the dynamic capacity of this packings was obtained to be 46.5 mg/g.The results showed that four proteins were completely separated in 10 min by linear gradient at a flow rate of 1.0 mL/min,and the retention time of packing increased with the increase of monomer,which was found to follow the cation exchange chromatographic(IEC) retention mechanism.