提出了高效液相色谱法测定洗发水中吡硫翁锌含量的方法。样品中吡硫翁锌用乙腈-甲醇(9+1)混合液超声提取,离心分离后,所得提取液过0.45 μm滤膜过滤。以MG C18色谱柱(250 mm×4.6 mm,5 μm)为分离柱,以下述3种组分按不同比例配成的混合液作流动相进行梯度洗脱:组分A为含0.01 mol·L-1磷酸二氢钾和0.5 mmol·L-1 EDTA的混合溶液;组分B为乙腈;组分C为甲醇。于波长272 nm处用二极管阵列检测器检测。吡硫翁锌的质量浓度在3.20~200.0 mg·L-1范围内与其峰面积呈线性关系,方法的检出限(3S/N)为0.15 g·kg-1。以空白洗发水样品为基体,采用标准加入法做回收试验,测得回收率在87.2%~89.1%之间,测定值的相对标准偏差(n=6)在2.6%~6.2%之间。

Content of zinc pyrithione in shampoo was determined by HPLC. The sample was extracted ultrasonically with a mixture of acetonitrile-methanol (9+1). After centrifugation, the extract was filtered on 0.45 μm filtering membrane. MG C18 (4.6 mm×250 mm, 5 μm) chromatographic column was used as stationary phase, and mixtures of the following 3 components mixed in various ratios were used as mobile phase in the gradient elution: (A) mixed solution containing 0.01 mol·L-1 KH2PO4 and 0.5 mol·L-1 EDTA; (B) acetonitrile; (C) methanol. The eluate obtained was determined with DAD at the wavelength of 272 nm. Linear relationship between values of peak area and mass concentration of zinc pyrithione was kept in the range of 3.20-200.0 mg·L-1, with detection limit (3S/N) of 0.15 g·kg-1. Using blank sample of shampoo as matrix, values of recovery found by standard addition method were in the range of 87.2 %-89.1%., with RSD′s (n=6) in the range of 2.6%-6.2%.