离子液体-分散液液微萃取高效液相色谱法测定配方奶粉中V_A

Determination of retinol in formula by ionic liquid based dispersive liquid liquid microextraction followed by HPLC

建立了基于离子液体的分散液液微萃取技术,并结合高效液相色谱法对配方奶粉中的VA进行测定。优化的实验条件包括萃取剂的种类及体积、分散剂种类及体积、溶液的p H值、离子强度等因素。结果显示最佳提取条件为:4 m L配方奶粉皂化液中加入5 m L二次蒸馏水稀释后,调节其p H=3,加入等体积乙腈稀释的100μL[C8MIM][PF6]萃取剂进行萃取后测定。并将该方法用于市售配方奶粉中VA含量的测定,加标回收率为83.6%~106.1%,相对标准偏差为1.86%~6.94%。该方法具有绿色环保,操作简捷,萃取率高,样品和试剂耗量少等优点。

A novel method was developed for the extraction and determination of retinol in formula using ionic liquid based dispersive liquid-liquid microextraction followed by HPLC. Experimental parameters including type and volume of extraction solvents and dispersers, the sample solution p H, addition of salt were examined and optimized by the extraction rate on retinol. The results showed the influencing parameters selected were 4 m L of saponified extract diluted with 5 m L water, adjusting p H=3, when adding the diluted 100 μL[C8 MIM][PF6]（extraction solvent） with the same volume of acetonitrile to the aqueous solution. The developed method was successfully applied to the determination of retinol in formula collected locally. Average recovery varied from 83.6% to 106.1%, with RSD in the range of 1.86%~6.94%.The method has the advantages of environmental friendly, simple operation, high extraction rate, less sample and reagent consumption.