Tsang W M, Howell M J, Miller A L
Department of Chemical Pathology, University College and Middlesex School of Medicine, London, UK.
Ann Clin Biochem. 1988 Mar;25 ( Pt 2):162-8. doi: 10.1177/000456328802500206.
A method is described based on a reaction that requires magnesium-ATP as a co-factor for the activity of hexokinase (HK), coupled with glucose 6-phosphate dehydrogenase (G6PDH). Glucose and NADP are converted to D-gluconolactone 6-phosphate and NADPH, respectively. The rate of increase in absorbance at 340 nm due to the formation of NADPH is proportional to the magnesium concentration in the sample. Magnesium levels in serum and urine measured by the enzymic method compared well with those obtained by atomic absorption spectrometry. The within-batch precisions were 1.4% and 1.5% for the enzymic method and the atomic absorption method, respectively for a quality assurance sample with a magnesium concentration of 2 mmol/L. The enzymic method is accurate (recoveries of added magnesium to serum samples are 101-102%), reproducible (between batch CV 2.8%), and rapid (23 samples may be measured in 10 min). Data on accuracy, precision and correlation for the enzymic and atomic absorption methods are presented.
本文描述了一种基于某种反应的方法，该反应需要镁 - ATP作为己糖激酶（HK）活性的辅助因子，并与葡萄糖6 - 磷酸脱氢酶（G6PDH）偶联。葡萄糖和NADP分别转化为6 - 磷酸葡萄糖酸内酯和NADPH。由于NADPH形成导致的340 nm处吸光度的增加速率与样品中的镁浓度成正比。用酶法测定的血清和尿液中的镁水平与用原子吸收光谱法测得的结果相当。对于镁浓度为2 mmol/L的质量保证样品，酶法和原子吸收法的批内精密度分别为1.4%和1.5%。酶法准确（向血清样品中添加镁的回收率为101 - 102%）、可重复（批间变异系数为2.8%）且快速（10分钟内可测定23个样品）。文中给出了酶法和原子吸收法的准确度、精密度及相关性数据。
