Invisible Analyte Peak Deformations in Single-Component Liquid Chromatography

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• 作者：Jö ; rgen Samuelsson ; Robert Arnell ; and Torgny Fornstedt
• 刊名：Analytical Chemistry
• 出版年：2006
• 出版时间：April 15, 2006
• 年：2006
• 卷：78
• 期：8
• 页码：2765 - 2771
• 全文大小：141K
• 年卷期：v.78,no.8(April 15, 2006)
• ISSN：1520-6882

文摘

It is well known that if a small excess of solute is injectedinto a chromatographic system equilibrated with an eluentcontaining the same solute, a single so-called perturbationpeak will appear in the chromatogram. It was recentlyshown (Samuelsson, J.; Forssén, P.; Stefansson, M.;Fornstedt, T. Anal. Chem. 2004, 76, 953-958) that thispeak consists of displaced plateau molecules; the injectedmolecules (mass peak) elute later, together with a deficiency of plateau molecules and are therefore not detected. In this article, we investigated what happens if alarge rather than a small excess of solute molecules isinjected. To study this systematically, the experimentalmethod involved an enantiomer pair in an achiral separation system. It was found that the invisible mass peak wasextremely deformed and that its shape depended on theamount of excess injected, the eluent concentration, andthe column length. Depending on these operational conditions, the mass peak changed from a classical Langmuirian (tailing) to an anti-Langmuirian (leading) shape,with deformed shapes observable in the transition. Thevisible, overloaded perturbation peak was always Langmuirian, regardless of the mass peak shape.