Capillary zone electrophoresis with UV-scanning detection for the analysis of metal species and their organic binding partners in biological systems

✍ Scribed by Theobald, Anne ;Dunemann, Lothar

• Publisher: John Wiley and Sons
• Year: 1996
• Tongue: English
• Weight: 528 KB
• Volume: 19
• Category: Article
• ISSN: 0935-6304
• DOI: 10.1002/jhrc.1240191103

✦ Synopsis

Abstract

A capillary zone electrophoretic method with UV‐scanning detection for the separation and identification of both free ligands and metal species is presented. The electrophoretic behavior of naturally occurring binding partners such as organic acids and amino acids was studied and compared with their metal‐complexes. Copper(II) complexes of citrate and amino acids showed decreased electrophoretic mobilities and altered UV spectra. The optimized method was validated on ultrafiltered cow's milk and human milk samples. In cow's milk six low molecular weight substances, including citrate, orotate, and hippurate, could be separated. Metal supplementation with Cu(II), Ni(II), or Zn(II) decreased not only the citrate peak but also the orotate signal and in the case of copper(II) supplementation a new signal for the copper(II)‐citrate complex appeared. In human milk samples various amino acids such as glutamate, phenylalanine, tyrosine, and tryptophan could be identified besides citrate. The electrophoretic mobilites and peak areas of the amino acids were also influenced by the metal supplementation.