高效液相色谱荧光法测定营养素补充制剂中维生素K2（MK-7）的含量

Determination of Vitamin K2 (MK-7) in Nutrient Supplements by High Performance Liquid Chromatography-Fluorescence Spectrometry

摘要:

建立高效液相色谱荧光法（HPLC-FLD）测定营养素补充制剂中维生素K2（MK-7）的含量。样品用异丙醇超声提取30 min，提取液离心过滤后取样液10 μL注入液相色谱系统中。样液经安捷伦C18色谱柱(4.6 mm×150 mm，5 μm)或其他等效色谱柱分离，柱后采用锌粉还原柱（4.6 mm×50 mm）衍生，使样品中维生素K2（MK-7）具有荧光特性。以甲醇（含5%四氢呋喃，冰乙酸0.03%，乙酸锌1.0 g/L）为流动相，流速1.0 mL/min，检测波长 激发波长243 nm发射波长430 nm。当称取样品1.0 g，定容体积为10 mL时，MK-7的检出限为0.03 μg/g，定量限为0.1 μg/g；MK-7在浓度0~2.176 μg/mL的范围内线性关系良好，线性相关系数为R2=0.9999；重复性实验中RSD%为0.97%；样品加标回收率为93.40%。此方法操作简单，高效，准确，重现性好，可用于营养素补充制剂中维生素K2（MK-7）的含量测定。

Abstract:

To establish a method for the determination of Vitamin K2 (MK-7) in Nutrient Supplements by high performance liquid chromatography-fluorescence detector (HPLC-FLD), the sample was extracted by isopropanol ultrasonic for 30 min, after centrifugation and filtration, 10 μL of the sample solution was injected into the liquid chromatography system. The sample solution was separated by Agilent C18 column (4.6 mm×150 mm, 5 μm) or equivalent column. After the column, it was derived by zinc powder reduction column (4.6 mm×50 mm), so that the Vitamin K2 (MK-7) in the sample had fluorescence characteristics. Methanol (containing 5% tetrahydrofuran, glacial acetic acid 0.03%, zinc acetate 1.0 g/L) was used as mobile phase, the flow rate was 1.0 mL/min, the fluorescence detector was set at λex/λem=243 nm/430 nm. When the sample weight was 1.0 g and the volume was 10 mL, the detection limit of this method was 0.03 μg/g, and the quantitative limit was 0.1 μg/g, MK-7 had a good linearity in the range of 0~2.176 μg/mL, the R2 was 0.9999. The relative standard deviation of the repeatability experiment was 0.97%, and the recovery of the standard was 93.40%. This method has simple operation, good accuracy, and good reproducibility. It can be used for the determination of MK-7 in Nutrient supplements.