高效液相色谱法测定苦丁茶中孔雀石绿残留量

Determination of Malachite Green Residue in Ilex latifilia Thunb by High Performance Liquid Chromatography

建立一种高效液相色谱法测定苦丁茶中孔雀石绿残留量(以孔雀石绿和隐色孔雀石绿之和计)的分析方法。分析采用Thermo Hypersil GOLD C_(18)(4.6 mm×250 mm,5μm)色谱柱连接氧化柱,流动相A为20 mmol/L乙酸铵溶液(pH值4.5),流动相B为乙腈,梯度洗脱,流速1.0 mL/min,柱温30℃。结果表明,孔雀石绿在3.0~60.0 ng/mL质量浓度范围内线性良好,相关系数R为0.9987;隐色孔雀石绿在9.0~180.0 ng/mL质量浓度范围内线性良好,相关系数R为0.9999。该方法回收率范围在96.7%~111.4%,相对标准偏差在1.1%~5.8%。孔雀石绿定量限为5μg/kg,隐色孔雀石绿定量限为15μg/kg。该方法灵敏度高、结果准确可靠,可适用于苦丁茶中孔雀石绿残留量的测定。

To establish a HPLC method for the determination of malachite green and cryptic malachite green residues in Ilex latifilia Thunb.Thermo Hypersil GOLD C_(18)(4.6 mm×250 mm,5μm)column was used for analysis.Mobile phase A was 20 mmol/L ammonium acetate solution(pH 4.5),mobile phase B was acetonitrile,gradient elution,flow rate was 1.0 mL/min,column temperature was 30℃.Results the linear range of malachite green was 3.0~60.0 ng/mL,and the correlation coefficient R was 0.9987.In the concentration range of 9.0~180.0 ng/mL,the linearity was good and the correlation coefficient R was 0.9999.The recoveries were in the range of 96.7%to 111.4%,and the relative standard deviations were in the range of 1.1%to 5.8%.The limit of quantification of malachite green was 5μg/kg,and the limit of quantification of cryptic malachite green was 15μg/kg.The method was sensitive,accurate and reliable,and could be used for the determination of malachite green residue in Ilex latifilia Thunb.