Holmberg I, Kristiansen T, Sturén M
Scand J Clin Lab Invest. 1984 Jun;44(4):275-82. doi: 10.3109/00365518409083808.
Four different HPLC methods for analysis of 25-hydroxyvitamin D3 in serum were evaluated with a method based on isotope dilution-mass spectrometry (ID-MS). Method I utilized Sephadex LH-20 chromatography as the only prepurification step. No correlation with the ID-MS method was obtained. Method II utilized Sephadex LH-20 chromatography and a subsequent reversed phase HPLC step as prepurification. The correlation coefficient was 0.99 (regression coefficient 1.2 and intercept - 3.9 micrograms/l). Method III included open silicic acid chromatography and straight phase HPLC as prepurification. The correlation when compared with the ID-MS method was 0.94 (regression coefficient 1.2 and intercept - 0.4 micrograms/l). In method IV Sep-pak C18 chromatography and open silicic acid chromatography were used as prepurification. The correlation coefficient when compared with the ID-MS method was 0.97 (regression coefficient 0.8 and intercept 0.1 microgram/l). It is concluded that a single Sephadex LH-20 step is not sufficient as prepurification and that method IV had an accuracy sufficient for its intended use to analyse 25-hydroxyvitamin D3 in serum from cattle.
采用基于同位素稀释质谱法（ID-MS）的方法对四种不同的用于分析血清中25-羟基维生素D3的高效液相色谱法进行了评估。方法I仅将葡聚糖凝胶LH-20色谱作为预纯化步骤。未获得与ID-MS方法的相关性。方法II将葡聚糖凝胶LH-20色谱及随后的反相高效液相色谱步骤用作预纯化。相关系数为0.99（回归系数1.2，截距为-3.9微克/升）。方法III包括开放硅酸色谱和正相高效液相色谱作为预纯化。与ID-MS方法相比时的相关性为0.94（回归系数1.2，截距为-0.4微克/升）。在方法IV中，Sep-pak C18色谱和开放硅酸色谱用作预纯化。与ID-MS方法相比时的相关系数为0.97（回归系数0.8，截距为0.1微克/升）。得出的结论是，单一的葡聚糖凝胶LH-20步骤作为预纯化是不够的，并且方法IV具有足够的准确性用于其预期用途，即分析牛血清中的25-羟基维生素D3。
