Determination of pKa values of organic bases in aqueous acetonitrile solutions using capillary electrophoresis

被引:47
作者
Buckenmaier, SMC
McCalley, DV [1 ]
Euerby, MR
机构
[1] Univ W England, Ctr Res Analyt Methods & Sensors, Bristol BS16 1QY, Avon, England
[2] AstraZeneca R&D Charnwood Lund, Pharmaceut & Analyt R&D, Loughborough LE11 5RH, Leics, England
关键词
ionisation constants; organic bases;
D O I
10.1016/S0021-9673(03)00717-9
中图分类号
Q5 [生物化学];
学科分类号
071010 ; 081704 ;
摘要
Capillary electrophoresis (CE) was used for the determination of ionisation constants (pK(a)) of a variety of organic bases in aqueous acetonitrile solutions over the range 0-60% (vW/v) acetonitrile. These bases are used as test compounds in HPLC column evaluation, thus knowledge of their pK(a) in hydro-organic solutions is useful. The base pK(a) decreased with acetonitrile concentration and significant shifts from the aqueous pK(a) (up to -0.8) were found using 60% acetonitrile. The CE application was confirmed to be very suitable for fast and accurate pK(a) measurement in aqueous organic solutions. (C) 2003 Elsevier B.V. All rights reserved.
引用
收藏
页码:71 / 79
页数:9
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