固相萃取-高效液相色谱法同时测定降糖茶中7种胰岛素分泌促进剂

Simultaneous Determination of 7 Insulinotropic Agents in Jiangtang Tea by Solid Phase Extraction-High Performance Liquid Chromatography

建立了固相萃取-高效液相色谱（SPE-HPLC）同时测定降糖茶中7种胰岛素分泌促进剂的方法.试样经甲醇超声提取、NH2固相萃取柱净化后,采用Agilent ZorbaxSB-C18色谱柱（250 mn×4.6 mm,5μm）进行分离,以乙腈-0.02％磷酸溶液为流动相,梯度洗脱,流速1.0 mL/min,柱温30℃,检测波长228 nm.结果表明：在0.2～20.0 mg/L范围内,7种组分的线性相关系数均大于0.9999;检出限为0.10 ～0.13 mg/kg;定量限为0.30 ～0.40 mg/kg.添加浓度水平为1.0,2.0,5.0 mg/kg时,回收率为84.5％ ～ 110.0％;RSD＜5.0％.

A solid phase extraction coupled with high performance liquid chromatographic method has been developed for the simultaneous determination of 7 insulinotropie agents in Jiangtang Tea. As a result, various samples were extracted with methanol by ultrasound, and the extract was cleaned up on an NH2 SPE column. The chromatographic separation was performed on an Agilent Zorbax SB-C18 column （250 mm×4.6 mm, 5 μm） using aeetonitrile-0.02% phosphoric acid solution with gradient elution as the mobile phase with a flow rate at 1.0 mL/min, column temperature at 30℃and ultraviolet （UV） detection at wavelength of 228 nm. There were good linear correlations between the concentrations and peak areas of the seven insulinotropie agents, the linear range was 0.2-20.0 mg/L and correlation coefficients were above 0. 9999. The limits of detection （LOD） of the seven insulinotropic agents were in the range of 0. 10-0. 13 mg/kg, limits of quantification （LOQ） were in the range of 0.30-0.40 mg/kg. The average recoveries for all components were 84.5%-110.0% and the relative standard deviations （RSDs） were less than 5.0% at spiked levels of 1.0, 2.0 and 5.0 mg/kg.