【作者】 韩超；

【导师】 雷根虎；

【作者基本信息】 西北大学 ， 分析化学， 2010， 硕士

【摘要】 反相色谱是目前应用最为广泛的一种液相色谱模式,它能分析分离大多数有机化合物,但对于强极性化合物,反相色谱并不能提供很好的分离。与反相色谱不同,亲水色谱使用极性固定相、水/有机溶剂作为流动相,能对强极性化合物提供很好的分离,已广泛应用于糖类、氨基酸、多肽、蛋白质、核苷、药物等的分析分离。本论文采用二醇基、氨基、δ-葡萄糖酸内酯三种键合固定相,通过改变流动相中有机溶剂、盐和有机酸的种类及其浓度、柱温等条件,系统研究了强极性中药组分在亲水作用色谱中的保留行为,期望为中药有效成分的分离提取奠定基础。具体工作如下：1.通过改变流动相中乙腈、甲醇和四氢呋喃的浓度,研究了有机溶剂种类及其浓度对溶质保留行为的影响。一般地,流动相中水比例在0-100%(v/v)变化时,溶质的保留随水浓度变化呈“U”型曲线,证明所用溶质的保留属于亲水色谱和反相色谱的混合保留机理,而“U”型曲线形状与有机溶剂、固定相性质和溶质分子结构有关。在同一固定相上,采用乙腈时,溶质的保留最强。2.流动相水相中缓冲盐分别选择甲酸铵、甲酸钠、乙酸钠、乙酸铵,通过改变盐浓度研究了溶质在三种固定相上的保留行为。在二醇硅胶中,溶质保留均随盐浓度增加而增强,而在氨丙基硅胶和δ-葡萄糖酸内酯键合硅胶中,酸性溶质保留随盐浓度增加而减弱,分析了产生该现象的原因。还发现,盐种类对溶质保留的影响不符合Hofmeister效应,没有规律可循。3.研究了流动相中添加的乙酸、甲酸、三氟乙酸对溶质在固定相上保留行为的影响。结果发现,在二醇、氨丙基和δ-葡萄糖酸内酯键合固定相上,外加酸对中性溶质保留影响较小,而对酸性溶质保留影响较大。提出在中药组分的分析中,流动相中乙酸、甲酸添加量应控制在0-0.5%,三氟乙酸应控制在0-0.1%为宜。4.在10-50℃范围内研究了柱温对溶质保留的影响。随着温度的升高,在二醇硅胶中,溶质保留均降低；而在氨丙基硅胶和δ-葡萄糖酸内酯键合硅胶中,各个溶质表现出不同的变化趋势。用Van’t Hoff作图法,分析了溶质在三种固定相上的驱动力。更多还原

【Abstract】 Reversed phase liquid chromatography (RPLC) is currently the most popular method in the field of high performance liquid chromatography (HPLC) as it is effective for varities of organic compounds. However, many polar compounds are difficult to be separated by RPLC. Contrary to RPLC, hydrophilic interaction chromatography (HILIC) use polar stationary phase and aqueous/organic mobile phase and can provide an approach to effectively separate polar compounds, thus it has been used in the separation and analysis of carbohydrates, amino acids, peptides, proteins, nucleotides, pharmaceutical drugs, etc. In this thesis, the retention behaviors of six polar compounds from traditional Chinese medicine were investigated systematically with HILIC on three of the most widely used stationary phase by changing organic solvent types and concentration, additives (salt and organic acid) in mobile phase and column temperature. The obtained results are as follows:1. The influences of organic solvents type and concentration on retention behaviors of solutes were investigated by changing concentration of acetonitrile, methanol and tetrahydrofuran in mobile phase. Generally, the retention curves of six solutes exhibited "U" shape with the change in the concentration of water from 0 to 100% (v/v) in mobile phase, indicating a mixed-mode of hydrophilic interaction and reversed phase chromatography. The retention curves of "U" shape were related with properties of organic solvents and stationary phase and molecular structures of solutes. On the same stationary phase, the retentions of solutes were strongest when acetonitrile was used in mobile phase.2. The influences of different concentration of HCOONH4, CH3COONH4, HCOONa and CH3COONa on retention behaviors of solutes were studied. The retention times of all solutes increased with increase of salt concentration on diol silica column, while the retentions of acidic solutes were found to decrease with increase of salt concentration on aminopropyl and 8-glucolactone bonding silica column. The reason of this phenomenon was elucidated. Also, it was found that influences of salt type on retentions of solutes were not consistent with Hofmeister effects.3. The influences of CH3COOH, HCOOH and TFA on retention behaviors of solutes was studied. The results indicated that the retentions of neutral solutes had less variation, but retentions of acidic solutes had more variation upon adding organic acid in mobile phase. In analysis of traditional Chinese medicine, the amount of HCOOH and CH3COOH added should be 0-0.5%, and TFA should be 0-0.1% in the mobile phase.4. The influences of column temperature on retention of solutes were investigated in the range 10-50℃. As temperature raised, retentions of all solutes decreased gradually on diol silica column, while had a different variation trend in aminopropyl andδ-glucolactone bonding silica column. By Van’t Hoff method, the driving force for the transfer of solutes from mobile phase to stationary phase was deduced.更多还原