Basicity of the Amino Groups of the Aminoglycoside Amikacin Using Capillary Electrophoresis and coupled CE-MS-MS techniques.

June 1, 2001

Journal Article

Basicity of the Amino Groups of the Aminoglycoside Amikacin Using Capillary Electrophoresis and coupled CE-MS-MS techniques.

Abstract

This paper describes the use of capillary electrophoresis (CE) and coupled CE and mass spectrometric techniques (CE-MS-MS) to measure the values of the pKa of the amino groups of small molecules -- of the aminoglycoside antibiotic amikacin, and of its acetylated derivatives. These values of pKa (8.4, 6.7, 9.7, and 8.4) were determined by measuring the electrophoretic mobilities of the molecules as a function of pH; they are within 0.7 units of certain values reported in the literature (by 13C and 15N NMR spectroscopies [Gaggelli, 1995 #805] [Cox, 1997 #806]), and resolved ambiguities left by these earlier studies. The observed variation in the values of pKa of an amino group in different acetylated derivatives also indicated the complex dependence of the degree of ionization on the environment of the ionizable group.

Revised: January 17, 2003 | Published: June 1, 2001

Citation

Kane R.S., P.T. Glink, R.G. Chapman, J.C. Mcdonald, P.K. Jensen, H. Gao, and L. Pasa-Tolic, et al. 2001. Basicity of the Amino Groups of the Aminoglycoside Amikacin Using Capillary Electrophoresis and coupled CE-MS-MS techniques. Analytical Chemistry 73, no. 16:4028-4036. PNNL-SA-34179.