Determination of conditional stability constants for phytic acid complexes with Mg2+, Ca2+ and Zn2+ ions using electrospray ionization mass spectrometry

摘要

The electrospray ionization mass spectrometry competitive method has been used for the determination of the conditional stability constants of phytic acid complexes with Mg2+, Ca2+ and Zn2+ ions. The competing complexation between ethylenediaminetetraacetic acid (EDTA) and phytic acid was studied. For EDTA complexes with Mg2+, Ca2+ and Zn2+ ions, the values of the conditional stability constants are known and were used for the calculation of this constant for the phytic acid complexes. The values obtained are in agreement with the literature data. The method applied permitted a fast and simple determination of conditional stability constants by measuring the response of the ionized coordination complexes.