Piatkowski Wojciech, Kramarz Renata, Poplewska Izabela, Antos Dorota
Rzeszów University of Technology, Chemical Engineering and Process Control Department, al. Powstańców Warszawy 6, 35-959 Rzeszów, Poland.
J Chromatogr A. 2006 Sep 15;1127(1-2):187-99. doi: 10.1016/j.chroma.2006.06.018. Epub 2006 Jul 11.
Gradient elution has been studied in typical normal and reversed-phase systems. Deformations of gradient profiles have been evidenced as a result of preferential adsorption of modifiers of the mobile phase. This phenomenon was pronounced in the normal-phase system, for which gradient profiles deviated significantly from those programmed. This influenced the retention and shapes of band profiles of the eluting solute. Hence, in order to predict gradient propagation correctly the adsorption equilibrium of modifiers has been quantified. Moreover, at low modifier content, deformations of band profiles of the solute has been registered as a result of the competitive adsorption in the system solute-modifier. This effect has been predicted by a competitive adsorption model. For the reversed-phase systems the influence of the modifier adsorption on gradient propagation was insignificant for typical mobile phases investigated. Therefore, the work has been focused on gradient predictions in the normal-phase system.
已在典型的正相和反相系统中研究了梯度洗脱。由于流动相改性剂的优先吸附，已证明梯度曲线存在变形。这种现象在正相系统中很明显，其梯度曲线与程序设定的曲线有显著偏差。这影响了洗脱溶质的保留时间和谱带形状。因此，为了正确预测梯度传播，已对改性剂的吸附平衡进行了量化。此外，在低改性剂含量下，由于溶质 - 改性剂体系中的竞争吸附，已记录到溶质谱带的变形。这种效应已由竞争吸附模型预测。对于反相系统，在所研究的典型流动相中，改性剂吸附对梯度传播的影响不显著。因此，这项工作主要集中在正相系统中的梯度预测上。
