抄録
A new method for the analysis of urinary magnesium using hexokinase (EC 2.7. 1.1) or glucokinase (EC 2.7.1.2) and glucose-6-phosphate dehydrogenase (EC 1.1.1.49) was established. The method is based on the determination of absorbance at 340 nm for NADPH formed by the overall reaction of hexokinase or glucokinase activated by Mg2+ and glucose-6-phosphate dehydrogenase. The reaction rate of hexokinase or glucokinase is proportional to the amount of Mg·ATP2- complex. This simple, enzymatic method does not require an expensive instrumentation, but it provides the results in excellent agreement with those obtained by atomic absorption spectrometry. Since the present method gives linearity over a wider range on the standard curve of magnesium than the currently used chelator method does, it permits direct determination on urine samples without previous dilution.
