An Abnormal Temperature Dependence of Alkylpyrazines’ Retention in Reversed-Phase Liquid Chromatography

Abstract

Retention behaviors of pyrazine and alkylpyrazines on various stationary phases in reversed-phase liquid chromatography were examined. An abnormal temperature effect on the retention of alkylpyrazines with a mobile phase consisting of acetonitrile and water was observed when changing the column temperature. On the other hand, no similar trend was found with a methanol-water mobile phase. For all the columns investigated in this work, the above tendency to the temperature-dependence was consistently observed, suggesting that the abnormal temperature effect on the retention of alkylpyrazines could be mainly induced by an acetonitrile-based mobile phase.

High-performance liquid chromatographic separation of unusual β3-amino acid enantiomers in different chromatographic modes on Cinchona alkaloid-based zwitterionic chiral stationary phases

“…However, on the ZWIX(−)™ column the behavior of 4, 10 and 16 was unique; k increased but α decreased, whereas increasing temperature. Increasing k and α values with increasing temperature were earlier observed for nonchiral separations (Adlof and List 2004;Wu et al 2004;and Yogo et al 2011) and recently also for separation of the enantiomers of neutral compounds (Matarashvili et al 2013) and zwitterionic compounds (Ilisz et al 2014b, c). It should be noted that this behavior was seen only on ZWIX(−)™ [not on ZWIX(+)™], indicating that the changes in the threedimensional structure and solvation of ZWIX(−)™ with temperature probably contribute to this unusual effect.…”

Investigation of Novel Cinchona Alkaloid-based Zwitterionic Chiral Stationary Phases in Cation- and Zwitterion-Exchange Modes

“…the k1 values increased with increasing temperature. This behavior was earlier registered in nonchiral separations [98][99][100] and for enantiomer separations [37,88] . This phenomenon was observed on ZWIX(-) Since the effect of temperature on the separation was complex, a detailed thermodynamic study may contribute to understand the mechanistic aspects of chiral recognition [97,[101][102][103] .…”

Development of an analytical method for yam saponins using HPLC with pulsed amperometric detection at different column temperatures

“…Different chemical compounds display exothermic or endothermic retention behaviors. This phenomenon can be inverted by the organic modifier or buffer type of the mobile phase , and by the stationary phase type . Temperature effects influence the selectivity and resolution, and can improve the chromatographic results .…”

“…Although the column temperature is less influential than these other parameters, it is a useful tool to optimize chromatographic parameters, such as the capacity factor and selectivity. Many studies have investigated the relationship between the retention value and temperature with reversed‐phase and ion‐exchange chromatography methods . These previous studies show the importance of temperature control to achieve optimal separation between the compounds.…”