反相高效液相色谱法测定奶粉中的烟酸和烟酰胺

本文采用反相高效液相色谱法，经过对样品进行热水草取、酸性沉淀蛋白质等简单的前处理，用１５ｃｍ×４．６ｍｍＣ１８色谱柱分窝，流动相为７．１％甲醇、３．０％异丙醇、９．１％的０．００５ｍｉｌ辛烷磺酸钠水溶液（高氯酸调ｐＨ＝２．１０），紫外２６１ｎｍ检测，采用标准加入法进行定量分析。本方法变异系数ＣＶ％＝１．５９，回收率范围９３．４３％～１０１．５１％。烟酸的最低检出限为４．０×００－１０ｇ；烟酰胺的最低捡出限为５．２×１０－１０ｇ。

APPLICATION OF RPLC TO DETERMINATION OF NIACIN AND NIACINAMIDE IN MILK POWDER

reverse phase high performance liquid chromatographic method hasbeen developed for determination of niacin and niacinamide in milk powder.The samples were dissoluted with warm and extracted by using sonic bath.Adjusting the pH until the protein was precipitated. The vitamin PP could be saperated from others contaminants on 15cm× 4.6mm C18 column and a mobile phase of 0.005mol/L octane sulfonic acid sodium salt in water conta-ining 7%methanol and 2%isopropanol (adjusted pH to 2.10 using petcnl-oric acid).Vitamin PP could be detected at UV 261nm,The quantitaive methodwas standard addition,The CV was 1.59%and the recovery rate was 93.66%-99.37%.The minimun detectable value of niacin was 4.0 × 10-10g and nia-cinamide was 5.2×10-10g. It was suggested that the present procedure was sim-ple,rapid,accurate,economic and can be applied to determine the vitaminPP in various milk powder.