HPLC法测定奶粉中痕量炔雌醇

建立了高效液相色谱（HPLC）法测定奶粉中炔雌醇残留量的方法。样品以乙腈振荡萃取、离心，提取液浓缩后经O．45μm滤膜过滤，冷冻去脂，进高效液相色谱仪分析。研究了萃取溶剂、萃取及浓缩方式对萃取效率的影响，确立了色谱检测条件。乙腈-水（50：50）为流动相，流速1mL／min，柱温30℃，检测波长224nm。方法的检出限为16μg／kg，加标回收率在86．5％～97．0％之间，工作曲线的相关系数为0．9990，相对标准偏差为0．95％～2．01％（n=3）。方法快速、灵敏度高、分离效果好，样品处理简单、无杂质干扰，能够满足奶粉中雌激素分析的需要。

Determination on Residue of Ethinylestradiol in Powdered Milk with HPLC

A method was developed for the determination of ethinylestradiol residue in pow- dered milk with HPLC. Samples were extracted with acetonitrile, contrifugated, the extract was fil- trated with 0.45 μm filter membrane after being concentrated, freezed and degreased, then carried out HPLC analysis. Extraction solution, extraction method and HPLC condition were optimized. Used acetonitrile-water（50：50） as the mobile phase, flowing speed was 1 mL/min, column tempera- ture was 30℃, de~ective wavelength was 224 nm. The detection limit of the method was 16 μg/kg, the recovery was 86.5%-97.0%, the related coefficient of the working curve was 0.999 O, the rela- tive standard deviation was 0.95%-2.01% （n = 3）. The method is rapid, sensitive, good seperation effect, simple, no disturbance from impurity, can meet the request of etinylestradiol dectection in powdered milk.