Determination of ionisation constants of organic bases in aqueous methanol solutions using capillary electrophoresis.

作者信息

Buckenmaier Stephan M C, McCalley David V, Euerby Melvin R

机构信息

Centre for Research in Analytical Methods and Sensors, University of the West of England, Frenchay, Bristol BS16 1QY, UK.

出版信息

J Chromatogr A. 2004 Feb 13;1026(1-2):251-9. doi: 10.1016/j.chroma.2003.11.007.

DOI:10.1016/j.chroma.2003.11.007

PMID:14763752

Abstract

The pKa of eight organic bases was determined in aqueous and aqueous methanol solutions of 0-70% (v/v) methanol using capillary electrophoresis. The bases investigated include compounds commonly used to test the activity of RP columns in HPLC. The variation of pKa with temperature in aqueous methanol solutions was also investigated and found to closely resemble temperature coefficients reported for bases in purely aqueous solutions. pKa values determined by CE were compared to those reported using NMR spectroscopy. The good agreement of the results is evidence that either technique is suitable to perform pKa measurements.

摘要