离子液体固定相离子色谱法测定淀粉中的顺反式丁烯二酸

Determination of Maleic Acid and Fumaric Acid in Starch Using Ion Chromatography with Ionic Liquid Stationary Phase

采用新型聚合离子液体嫁接硅胶多模式色谱固定相（Sil-pC11C1Im柱,4.6 mm×150 mm）,建立了淀粉中顺反式丁烯二酸的新型离子色谱测定方法。实验通过考察流动相的pH值和无机盐浓度对分离检测顺、反丁烯二酸的影响,得到优化的色谱条件：流动相为甲醇-10 mmol/L磷酸二氢钠（体积比为5∶95,pH7.0）,流速为1.0 mL/min,检测波长为215 nm,进样量为15μL。在优化条件下,顺反式丁烯二酸的线性范围为0.1～2.0 mg/L,回收率为93.0%～99.6%,相对标准偏差（RSD,n=5）为1.1%～7.6%,检出限（S/N=3）为0.02 mg/L,定量下限（S/N=10）为0.66 mg/kg。该方法样品前处理简单、快速,定性定量检测效果良好。

An ion chromatographic method was developed for the determination of maleic acid and fumaric acid in starch by using a home-made multi-mode stationary phase based on poly（ ionic liquid）-grafted silica（ Sil-pC11C1Im column,4. 6 mm × 150 mm）. The optimized chromatographic conditions were as follows： mobile phase： methanol-10 mmol /L NaH2PO4solution（ 5 ∶ 95,pH 7. 0）;flow rate： 1. 0 mL /min; detection wavelength： 215 nm; sample volume： 15 μL. The calibration curves of maleic acid and fumaric acid were linear in the concentration range of 0. 1-2. 0 mg /L. The average spiked recoveries were between 93. 0% and 99. 6% with RSDs of 1. 1%-7. 6%. The limits of detection（ S /N = 3） were 0. 02 mg /L,and the limits of quantitation（ S /N = 10） were 0. 66 mg /kg. The method was simple and rapid,and was suitable for the determination of the maleic acid and fumaric acid in starch sample.