目的 建立超高效合相色谱测定植物油中丁基羟基茴香醚(BHA)和二丁基羟基甲苯(BHT)的方法.方法 样品以正庚烷-异丙醇提取,体积比为80:20;应用超高效合相色谱仪,采用超临界CO2和甲醇-乙腈(体积比为50:50)梯度洗脱,经ACQUITY UPC2 BEH 2-EP色谱柱分离,二极管阵列检测器检测,以保留时间定性,外标法峰面积定量.结果 样品在50～200 mg/kg范围内,BHA的平均回收率在96.1％～99.3％之间,相对标准偏差为1.11％～1.30％;BHT的平均回收率在93.8％～99.4％之间,相对标准偏差为0.5％～4.0％.BHA和BHT的定量限均为25 mg/kg.结论 该方法具有分析时间快、溶剂消耗少的优点,能快速分析植物油中的BHA和BHT.
To develop a liquid chromatography tandem mass spectrometry(LC-MS/MS)method for the determination of vitamin D3 in milk products.The sample was saponified with ethanol – 50 % potassium hydroxide,followed by extraction with hexane and cleaned up by saturated sodium chloride solution. The chromatographic separation was performed on the YMC C18 column(50 mm×2.1 mm,3μm),using methanol-5 mmol/L ammonium formate solution as the mobile phase by gradient elution. The method applied positive electrospray ionization and multiple reaction monitoring mode and quantified with peak area with internal standard method.A good linearity was obtained for 0-50μg/L with a correlation coefficient above 0.99.The average recoveries from three different were with the range of 83.9% to93.0% at spiked levels of 20,100,200μg/kg,and the relative standard deviations were between 1.10% to 4.90%(n=6).The limit of quantification was 20μg/kg. This method is simple, accurate and suitable for determination of vitamin D3 in milk products.
建立用高效液相色谱法同时测定婴幼儿乳粉中维生素A和E质量分数.试样经乙醇-氢氧化钾溶液皂化后,经石油醚萃取,加入饱和氯化钠溶液,液液分配净化后,石油醚层氮气吹干,残渣以乙醇定容,C18色谱柱,甲醇-水溶液作为流动相,外标法峰面积定量.乳粉样品中维生素A质量分数在0.5～4mg/kg添加水平范围内,回收率为86.0％～93.0％,相对标准偏差为1.07％～4.04％(n=6);维生素E质量分数在20～100 mg/kg添加水平范围内,回收率为90.6％～94.0％,相对标准偏差为2.53％～3.93％.该法简单、快速、准确,满足检测需要,适合婴幼儿乳粉中维生素A和E的检测.
