浊点萃取-高效液相色谱法测定油脂中的胆固醇

Determination of Cholesterol in Oil and Fat Using Cloud Point Extraction by HPLC-UV

建立了一种简单快速的采用浊点萃取-高效液相色谱法测定油脂中的胆固醇的方法.以非离子表面活性剂Triton X-114为萃取剂,色谱柱为phenomenex C18,流动相为甲醇-乙醇等度洗脱,流速为0.8mL/min,检测波长为206nm.采用Triton X-114进行浊点萃取,分别优化了影响萃取效率的表面活性剂的浓度、盐浓度、平衡温度及时间等条件.胆固醇的质量浓度在0.10～150μg/mL范围内与其峰面积成良好的线性关系(r=0.999 79),该方法的定性检测限为0.03μg/mL(S/N=3),回收率为86.00%～93.50%,可以满足油脂中胆固醇含量的分离测定.

A fast,simple and sensitive sample preparation procedure based on cloud point extraction（CPE） is proposed for the determination of cholesterol in oil and fat using reverse phase high performance liquid chromatography（RP-HPLC） and UV detection.The non-ionic surfactant Triton X-114 was chosen as the extract solvent.The samples were analyzed on a Phenomenex C18 column with ethanol-methanol as the mobile phase using isocratic elution.The flow rate was 0.8 mL·min-1,and UV detection wavelength was set at 206 nm.Optimized conditions for the pretreatment of oil and fat included the concentration of the surfactant Triton X-114,the concentration of sodium chloride,equilibration temperature and equilibration time.A good linear correlation was observed to exist between the concentration of cholesterol in the range of 0.10-150 μg/mL and its peak area（r=0.999 79）.The limit of detection（LOD） was 0.03 μg/mL（S/N=3）,and the average recovery varied from 86.00% to 93.50%.This new method is fast,easy to operate,sensitive and environment-friendly,and can meet the requirements of determination of cholesterol of oil and fat.