caa a22 4500 469129344 CHVBK 20180323133200.0 cr unu---uuuuu 170328e19920701xx s 000 0 eng 10.1007/BF00321837 doi (NATIONALLICENCE)springer-10.1007/BF00321837 Advanced quality control for zinc speciation investigations in human breast milk [Elektronische Daten] [B. Michalke, D. Münch, P. Schramel] Summary: Information is provided about the reliability of results obtained in Zn-speciation analyses of human milk. For such analyses, convenient techniques have already been given in an earlier paper [1], comprising mass balances of metal and ligand, purity of analytes, etc. Here, however, the influence of the eluent was checked in an extended manner. For this series of experiments, bi-distilled water was compared with different buffers as the eluent. Water proved to be a more suitable mobile phase than buffers with regard to contamination. Moreover, a method was developed to investigate the possibility of a transfer of Zn among the proteins during size exclusion chromatography. For these experiments, casein and metallothionein were chosen as competitive Zn-ligands, showing extremely different affinities to Zn. A possible Zn-transfer from one protein to the other was examined in combining a Zn-containing protein with a Zn-free one. No change of the Zn-status of the proteins was detected, indicating a stable protein-metal complex under the experimental conditions. Zn and protein mass balances (injected/eluted) were calculated and found to be 100%. Springer-Verlag, 1992 Michalke B. GSF-Forschungszentrum für Umwelt und Gesundheit GmbH, Institut für Ökologische Chemie, Ingolstädter Landstrasse 1, W-8042, Neuherberg, Federal Republic of Germany aut Münch D. GSF-Forschungszentrum für Umwelt und Gesundheit GmbH, Institut für Ökologische Chemie, Ingolstädter Landstrasse 1, W-8042, Neuherberg, Federal Republic of Germany aut Schramel P. GSF-Forschungszentrum für Umwelt und Gesundheit GmbH, Institut für Ökologische Chemie, Ingolstädter Landstrasse 1, W-8042, Neuherberg, Federal Republic of Germany aut Fresenius' Journal of Analytical Chemistry Springer-Verlag 344/7-8(1992-07-01), 306-310 0937-0633 344:7-8<306 1992 344 216 https://doi.org/10.1007/BF00321837 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/BF00321837 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Michalke B. GSF-Forschungszentrum für Umwelt und Gesundheit GmbH, Institut für Ökologische Chemie, Ingolstädter Landstrasse 1, W-8042, Neuherberg, Federal Republic of Germany aut NATIONALLICENCE 700 1- Münch D. GSF-Forschungszentrum für Umwelt und Gesundheit GmbH, Institut für Ökologische Chemie, Ingolstädter Landstrasse 1, W-8042, Neuherberg, Federal Republic of Germany aut NATIONALLICENCE 700 1- Schramel P. GSF-Forschungszentrum für Umwelt und Gesundheit GmbH, Institut für Ökologische Chemie, Ingolstädter Landstrasse 1, W-8042, Neuherberg, Federal Republic of Germany aut NATIONALLICENCE 773 0- Fresenius' Journal of Analytical Chemistry Springer-Verlag 344/7-8(1992-07-01), 306-310 0937-0633 344:7-8<306 1992 344 216 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer