高效液相色谱法测定功能性食品中维生素C的含量

Determination of vitamin C in functional food by high performance liquid chromatography

目的建立高效液相色谱法测定功能性食品中维生素C的含量。方法采用Venusil XBP C_（18）（L）柱（4.6mm×250 mm,5mm）为色谱柱,0.1%的草酸溶液为流动相,流速为0.5 m L/min,柱温为25℃,检测波长为245nm,样品经L-半胱氨酸-三乙胺溶液还原后,测定维生素C的含量,进样量20mL。结果维生素C在2.056~30.84mg/m L浓度范围内呈良好线性关系（r=0.9999）,定量限为0.03726mg/m L,检出限为0.01242mg/m L,回收率为99.89%,RSD为0.31%（n=6）;样品经L-半胱氨酸-三乙胺溶液还原后稳定性、重复性好。结论本方法简便快捷、适用范围广、准确度高、精密度好,可广泛用于功能性食品中维生素C含量的测定。

Objective To establish a method of high performance liquid chromatography（HPLC） for the determination of vitamin C in functional food. Methods A Venusil XBP C18（L） column（4.6 mm×250 mm, 5 ？m） was used with 0.1% oxalic acid solution as mobile phase; the flow rate was 0.5 m L/min, the column temperature was 25 ℃, and the detection wavelength was set at 245 nm. After reduction by L-cysteine-triethylamine solution, samples ware determined with the injection volume of 20 ？L. Results Vitamin C had a good linear relationship in the range of 2.056~30.84 ？g/m L（the correlation index r=0.9999）, the quantitative limit was 0.03726 ？g/m L, the detection limit was 0.01242 ？g/m L, the average recovery was 99.89%, and RSD was 0.3%（n=6）. The stability and reproducibility of samples were ideal after reduction with L-cysteine-triethylamine solution. Conclusion The method is simple, applicable, accurate and precise, which can be widely used for the determination of vitamin C in functional foods.