A high performance liquid chromatographic method for the simultaneous determination of four fat soluble vitamins: retinol (vitamin A), cholecalciferol(vitamin D), tocopherol(vitamin E) and phylloquinone(vitamin K_1) i...A high performance liquid chromatographic method for the simultaneous determination of four fat soluble vitamins: retinol (vitamin A), cholecalciferol(vitamin D), tocopherol(vitamin E) and phylloquinone(vitamin K_1) in fortified milk powders and egg yolk has been developed. The method requires enzymatic hydrolysis of lipid component of the sample as a pretreatment. Several factors which influence the enzymatic hydrolysis were studied-Separation was achieved using μ-Bondapak C-18 column(3.9×300mm), 98% methanol as mobile phase, a double channel detection was selected; vitamins D_3 E_1 K_1 were detected by UV spectrophotometry (265 nm) first, then vitamin A by fluorometry (EX 325nm, EM 480mm). The retention times of vitamin A_1 D_3, E and K_1 4.87, 9.00, 10.58 and 15.45 min respectively. Detection limit were 0.64, 0.25, 0.50 and 0.07 ng; and the recoveries were 90.5%～103.6% 90.0%～95.6%, 91.7%～98.8%, 91.5%～98.6%, respectively. The vitamins A, D_0, E, K_1 contents in foods were determined satisfactorily.展开更多
建立了同时测定婴幼儿配方奶粉中维生素A、维生素E（包括）和D一胡萝卜素等脂溶性维生素的高效液相色谱测定法。采用Zorbax NH（5um，4．6mm×250mmi．d）色谱柱，以体积为750毫升正烷、250毫升甲基叔丁基醚和3毫升甲醇混合，还有...建立了同时测定婴幼儿配方奶粉中维生素A、维生素E（包括）和D一胡萝卜素等脂溶性维生素的高效液相色谱测定法。采用Zorbax NH（5um，4．6mm×250mmi．d）色谱柱，以体积为750毫升正烷、250毫升甲基叔丁基醚和3毫升甲醇混合，还有纯正己烷作为流动相，进样量100μL，柱温箱25℃。方法检出限0．0001～0．02mg／kg，加标回收率95％～101％，相对标准偏差为0．4％～0．6％。该法具有样品前处理简单，灵敏度高，分析时间短等优点，适用于婴幼儿配方奶粉中Vitamin A Palmitate、Vitamin E Acetate、Vitamin ESynthetic和B-carotene的同时测定。展开更多
建立了同时测定婴幼儿配方奶粉中多种维生素、牛磺酸等12种水溶性维生素的液相色谱串联质谱测定法。采用MGⅢ-C18色谱柱,以质量分数为0.1%甲酸水溶液-甲醇为流动相(梯度洗脱),流速为0.25 m L/min,柱温25℃,进样量5μL。方法检出限0.0001...建立了同时测定婴幼儿配方奶粉中多种维生素、牛磺酸等12种水溶性维生素的液相色谱串联质谱测定法。采用MGⅢ-C18色谱柱,以质量分数为0.1%甲酸水溶液-甲醇为流动相(梯度洗脱),流速为0.25 m L/min,柱温25℃,进样量5μL。方法检出限0.0001~1 mg/kg,高、中、低不同质量分数加标回收率85.0%~95.5%,相对标准偏差为2.9%~9.1%。该法具有样品预处理简单,灵敏度高,分析时间短等优点,适用于婴幼儿配方奶粉中上述12种水溶性维生素的同时测定。展开更多
目的：应用荧光分光光度计对婴幼儿乳品中维生素C的含量进行测定。方法以婴幼儿奶粉为例,依据国家标准GB 5413.18-2010《食品安全国家标准婴幼儿食品和乳品中维生素C的测定》,应用日立F-4600型荧光分光光度计测定婴幼儿乳品中维生素 C ...目的：应用荧光分光光度计对婴幼儿乳品中维生素C的含量进行测定。方法以婴幼儿奶粉为例,依据国家标准GB 5413.18-2010《食品安全国家标准婴幼儿食品和乳品中维生素C的测定》,应用日立F-4600型荧光分光光度计测定婴幼儿乳品中维生素 C 的含量。结果线性方程为 Y=457.79X+28.877,相关系数为0.9993,方法检出限为0.1 mg/100 g。在50 mg/100 g、100 mg/100 g 两个加标水平下,加标回收率为91.8%~101.8%,相对标准偏差为0.36%~0.85%(n=6)。结论此方法操作简便,线性良好是测定食品中维生素C含量的理想方法。展开更多
文摘A high performance liquid chromatographic method for the simultaneous determination of four fat soluble vitamins: retinol (vitamin A), cholecalciferol(vitamin D), tocopherol(vitamin E) and phylloquinone(vitamin K_1) in fortified milk powders and egg yolk has been developed. The method requires enzymatic hydrolysis of lipid component of the sample as a pretreatment. Several factors which influence the enzymatic hydrolysis were studied-Separation was achieved using μ-Bondapak C-18 column(3.9×300mm), 98% methanol as mobile phase, a double channel detection was selected; vitamins D_3 E_1 K_1 were detected by UV spectrophotometry (265 nm) first, then vitamin A by fluorometry (EX 325nm, EM 480mm). The retention times of vitamin A_1 D_3, E and K_1 4.87, 9.00, 10.58 and 15.45 min respectively. Detection limit were 0.64, 0.25, 0.50 and 0.07 ng; and the recoveries were 90.5%～103.6% 90.0%～95.6%, 91.7%～98.8%, 91.5%～98.6%, respectively. The vitamins A, D_0, E, K_1 contents in foods were determined satisfactorily.
文摘建立了同时测定婴幼儿配方奶粉中维生素A、维生素E（包括）和D一胡萝卜素等脂溶性维生素的高效液相色谱测定法。采用Zorbax NH（5um，4．6mm×250mmi．d）色谱柱，以体积为750毫升正烷、250毫升甲基叔丁基醚和3毫升甲醇混合，还有纯正己烷作为流动相，进样量100μL，柱温箱25℃。方法检出限0．0001～0．02mg／kg，加标回收率95％～101％，相对标准偏差为0．4％～0．6％。该法具有样品前处理简单，灵敏度高，分析时间短等优点，适用于婴幼儿配方奶粉中Vitamin A Palmitate、Vitamin E Acetate、Vitamin ESynthetic和B-carotene的同时测定。
文摘建立了同时测定婴幼儿配方奶粉中多种维生素、牛磺酸等12种水溶性维生素的液相色谱串联质谱测定法。采用MGⅢ-C18色谱柱,以质量分数为0.1%甲酸水溶液-甲醇为流动相(梯度洗脱),流速为0.25 m L/min,柱温25℃,进样量5μL。方法检出限0.0001~1 mg/kg,高、中、低不同质量分数加标回收率85.0%~95.5%,相对标准偏差为2.9%~9.1%。该法具有样品预处理简单,灵敏度高,分析时间短等优点,适用于婴幼儿配方奶粉中上述12种水溶性维生素的同时测定。
