摘要
在室温条件下,以甲基丙烯酸环氧丙酯(GMA)为单体,溴异丁酰溴为引发剂,CuCl/2,2′-联吡啶(Bpy)为催化剂,通过原子转移自由基聚合(ATRP)反应,将甲基丙烯酸环氧丙酯聚合在硅胶表面。然后再将L-苯丙氨酸共价键合在硅胶表面的聚合物上,制备了新型手性配体交换色谱固定相,并用该固定相对DL-氨基酸进行分离。用元素分析对其进行了表征;详细考察了固定相的合成过程以及流动相pH值、流动相铜离子浓度、柱温等色谱条件对DL-氨基酸对映体拆分的影响。元素分析得出该固定相表面L-苯丙氨酸接枝密度达到4.32 mg/m2;在手性配体交换分离模式下,流动相为0.05 mol/L KH2PO4-0.1 mmol/L Cu(Ac)2水溶液、流速为1.0 mL/min、柱温为50℃和检测波长为223 nm条件下,该色谱固定相可以分离DL-天冬氨酸、DL-天冬酰胺等。同时,流动相pH值、铜离子浓度以及柱温对手性对映体的拆分有较大影响。与传统的在硅胶表面直接键合L-苯丙氨酸制得的固定相相比,所合成的固定相接枝密度高,分离效果好,对DL-天冬氨酸及DL-天冬酰胺实现了基线分离。结果表明,在手性配体交换分离模式下,固定相具有良好的拆分性能。
A novel stationary phase was synthesized for chiral ligand-exchange chromatography via atom transfer radical polymerization（ATRP）.Glycidyl methacrylate（GMA） was grafted onto the surface of the silica by ATRP using bromoisobutyryl bromide as an initiator,and the organic metal compound formed in the CuCl/2,2′-bipyridine（Bpy） system as a catalyst at room temperature.The chiral stationary phase was then synthesized by grafting L-phenylalanine on the surface of the silica.The stationary phase was characterized by means of elementary analysis and evaluated in detail to determine its separability.The amount of L-phenylalanine on the surface of silica was calculated to be 4.32 mg/m2.The results showed that the good enantioseparations of some DL-amino acids were obtained using ligand-exchange chromatography on the synthesized chiral stationary phase（50 ℃） with 0.05 mol/L KH2PO4 and 0.1 mmol/L Cu（Ac）2 solution（pH 4.5） as the mobile phase at a flow rate of 1.0 mL/min and a wavelength of 223 nm.The influences of the mobile phase pH,concentration of Cu（Ⅱ）,and temperature of column on the resolution of DL-amino acids by ligand-exchange chromatography were investigated.The results showed that these conditions could affect the resolution of racemates.Compared with the column prepared by radical method using L-phenylalanine directly bonded onto the surface of the silica,the synthesized stationary phase showed a better separation ability,and the DL-aspartic acids and DL-asparagines could be separated at baseline.
出处
《色谱》
CAS
CSCD
北大核心
2011年第9期918-922,共5页
Chinese Journal of Chromatography
基金
科技部重大基础研究前期专项(2009CB626608)
国家自然科学基金项目(201065008)
宁夏自然科学基金项目(NZ0838)
关键词
原子转移自由基聚合
手性配体交换色谱
L-苯丙氨酸
对映体分离
atom transfer radical polymerization
chiral ligand-exchange chromatography
L-phenylalanine
resolution of racemates
