Rapid method for screening of both calcium and magnesium chelation with comparison of 21 known metal chelators

Abstract

The aim of this study was to develop an affordable, rapid but sensitive and precise method for determining the degree of chelation of calcium and magnesium ions. Spectrophotometric method using o-cresolphthalein complexone (o-CC) was developed and its biological relevance was confirmed in human platelets by impedance aggregometry. The method was developed and validated. Four and seven out of twenty-one chelators strongly chelated calcium and magnesium ions, respectively. Structure-activity relationships for eight quinolin-8-ols showed improvements in chelation particularly in the cases of dihalogen substitution, and a negative linear relationship between pKa and magnesium chelation was observed. Calcium chelation led to inhibition of platelet aggregation in concentrations corresponding to the complex formation.