Centre for Research in Biosciences, University of the West of England, Frenchay, Bristol, BS16 1QY, UK.
Analytical and Environmental Science Division, Faculty of Life Sciences & Medicine, King's College London, London, SE1 9NH, UK.
Anal Chim Acta. 2019 Jan 3;1045:141-151. doi: 10.1016/j.aca.2018.08.051. Epub 2018 Aug 28.
The separation of some zwitterionic, basic and neutral antibiotic and antiretroviral compounds was studied using hydrophilic interaction chromatography (HILIC) on bare silica, bonded amide and urea superficially porous phases. The differences in the selectivity and retentivity of these stationary phases were evaluated for compounds with widely different physicochemical properties (logD -3.43 to 2.41 at pH 3.0). The mobile phase was acetonitrile-ammonium formate buffered at low pH. Compounds containing quinolone and serine groups showed poor peak shapes on all columns, attributed to metal-oxide interactions with system metals. Peak shapes were improved by addition of citrate buffers. Gradient elution, particularly with regard to column equilibration, was also studied due to the large differences in retention factors observed under isocratic conditions. Full equilibration in HILIC was slow for both ionogenic and neutral solutes, requiring as much as ∼40 column volumes. However, highly repeatable partial equilibration, suitable for gradient elution, was achieved in only a few minutes. Pronounced selectivity differences in the separations were shown dependent on the partial equilibration time.
采用硅胶、酰胺键键合和脲键键合的表面多孔固定相，研究了两性离子、碱性和中性抗生素和抗逆转录病毒化合物的亲水作用色谱（HILIC）分离。评估了这些固定相在选择性和保留性方面的差异，这些固定相用于具有广泛不同物理化学性质的化合物（logD 值为-3.43 至 2.41，pH 值为 3.0）。流动相为低 pH 值下的乙腈-甲酸铵缓冲液。含有喹诺酮和丝氨酸基团的化合物在所有柱子上的峰形都很差，这归因于系统金属与金属氧化物的相互作用。通过添加柠檬酸盐缓冲液可以改善峰形。还研究了梯度洗脱，特别是关于柱平衡，因为在等度条件下观察到保留因子存在很大差异。对于离子型和中性溶质，HILIC 中的完全平衡都很慢，需要多达约 40 个柱体积。然而，仅需几分钟即可实现高度可重复的部分平衡，适用于梯度洗脱。分离中的选择性差异显著，取决于部分平衡时间。
