使用毛细管电泳法测定乙腈水溶液中有机碱的pKa值

Determination of pKa values of organic bases in aqueous acetonitrile 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. 2003 Jul 4;1004(1-2):71-9. doi: 10.1016/s0021-9673(03)00717-9.

DOI:10.1016/s0021-9673(03)00717-9

PMID:12929963

Abstract

Capillary electrophoresis (CE) was used for the determination of ionisation constants (pKa) of a variety of organic bases in aqueous acetonitrile solutions over the range 0-60% (v/v) acetonitrile. These bases are used as test compounds in HPLC column evaluation, thus knowledge of their pKa in hydro-organic solutions is useful. The base pKa decreased with acetonitrile concentration and significant shifts from the aqueous pKa (up to -0.8) were found using 60% acetonitrile. The CE application was confirmed to be very suitable for fast and accurate pKa measurement in aqueous organic solutions.

摘要

采用毛细管电泳（CE）法测定了多种有机碱在乙腈水溶液（乙腈体积分数为0 - 60%，v/v）中的电离常数（pKa）。这些碱用作高效液相色谱（HPLC）柱评价中的测试化合物，因此了解它们在水-有机溶剂中的pKa很有用。碱的pKa随乙腈浓度降低，且使用60%乙腈时发现其与水中pKa有显著偏移（高达-0.8）。已证实CE应用非常适合在水-有机溶剂中快速准确地测定pKa。