Institute of Chemical Methodologies, Italian National Research Council, Monterotondo, Italy.
Unit of Food Science and Nutrition, Department of Medicine, Università Campus Bio-Medico di Roma, Rome, Italy.
Electrophoresis. 2019 Aug;40(15):1966-1971. doi: 10.1002/elps.201800508. Epub 2019 Feb 12.
This work deals with the potentiality of nano liquid chromatography (Nano-LC) for the chiral separation of racemic mixture of tryptophan and some selected derivatives by using 100 µm i.d. fused silica capillary packed with teicoplanin bonded to 5 µm diol silica stationary phase. The experiments were carried out by using a cheap and laboratory-assembled nano-LC-UV system. Elution was done in an isocratic mode using a polar organic mobile phase. In order to find the optimum chiral separation of the studied enantiomers, some chromatographic experimental parameters were systematically studied and optimized. Among them, mobile phase composition, namely organic modifier type and concentration, buffer type and pH and aqueous content and sample solvent dilution on retention time, retention factor and enantioresolution factor were studied. Baseline enantioresolution and good peak shape was achieved utilizing the mobile phase containing 40 mM ammonium formate at pH pH 2.5 in ACN/water/acetone (60:30:10, v/v/v) at 520 nL/min in less than 8 min analysis time.
本工作研究了纳米液相色谱（Nano-LC）在使用内径为 100µm 的熔融二氧化硅毛细管填充 teicoplanin 键合到 5µm 二醇硅胶固定相，对手性混合物色氨酸和一些选定的衍生物进行对映体拆分的潜力。实验采用便宜的实验室组装的纳流 LC-UV 系统进行。采用极性有机流动相进行等度洗脱。为了找到研究对映体的最佳手性拆分条件，系统地研究和优化了一些色谱实验参数。其中，研究了流动相组成（有机改性剂类型和浓度、缓冲液类型和 pH 值以及水含量）以及样品溶剂稀释对保留时间、保留因子和对映体分离因子的影响。在 520nL/min 的流速下，在 8 分钟内分析时间内，利用含有 40mM 甲酸铵的流动相（在 ACN/水/丙酮（60:30:10，v/v/v）中 pH 为 2.5），可以实现基线分离和良好的峰形。
