Külpmann W R, Gerlach M
Medical University of Hanover, Institute of Clinical Chemistry, Germany.
Scand J Clin Lab Invest Suppl. 1996;224:251-8. doi: 10.3109/00365519609088645.
The relationship between the concentration of ionized magnesium and total magnesium was investigated. Ionized magnesium was determined by an ion-selective electrode (Microlyte 6, KONE) and the result was adjusted to pH 7.4. Total magnesium concentration was measured by flame atomic absorption spectrometry. Total and ionized magnesium were only closely related in marked hypermagnesaemia (> 1.2 mmol/L), but correlation was poor in samples with slightly elevated total concentration or in hypomagnesaemia (< 0.65 mmol/L). The relationship was dependent on protein concentration. The agreement between total and ionized magnesium was acceptable in normoproteinaemia, but in hypoproteinaemia (< 40 g/L) total magnesium concentration was classified in 35% of the samples as below or within the reference interval, whereas the pertinent ionized magnesium concentration was normal or elevated, instead. Studies on paraproteinaemic sera clearly demonstrated that albumin concentration is most important for the size of the protein bound fraction.
研究了离子化镁浓度与总镁浓度之间的关系。离子化镁通过离子选择电极（Microlyte 6，科纳公司）测定，并将结果校正至pH 7.4。总镁浓度通过火焰原子吸收光谱法测量。总镁和离子化镁仅在明显的高镁血症（>1.2 mmol/L）中密切相关，但在总浓度略有升高的样本或低镁血症（<0.65 mmol/L）中相关性较差。这种关系取决于蛋白质浓度。在正常蛋白血症中，总镁和离子化镁之间的一致性是可以接受的，但在低蛋白血症（<40 g/L）中，35%的样本总镁浓度被归类为低于或处于参考区间内，而相应的离子化镁浓度却正常或升高。对副蛋白血症血清的研究清楚地表明，白蛋白浓度对蛋白质结合部分的大小最为重要。
