高效毛细管电泳法测定葡萄酒中的苋菜红及亮蓝

Determination of Amaranth and Brilliant Blue in Wine by High Performance Capillary Electrophoresis

建立了高效毛细管电泳法直接分离测定葡萄酒中苋菜红及壳蓝的方法。研究了缓冲体系种类、pH值、缓冲溶液浓度及有机添加剂对分离效果的影响。确定的最佳实验条件：未涂层石英毛细管柱（50cm×75μm），分离缓冲溶液10mmol／L柠檬酸-5mmol／L∥一环糊精（pH2．6），检测波长220nm，电泳电压20kv，压力进样（20kPa×3s），电泳温度为室温。该方法测定的苋菜红及亮蓝质量浓度在2-200mg／L范围内线性良好，苋菜红及亮蓝的检出限分别为0．58，0．50mg／L，线性相关系数-≥0．9994，回收率在93．9％～107．2％之间。该方法无需样品预处理，操作简便，测定准确，能满足实际样品的分析需求。

A method by using high performance capillary electrophoretic for the direct determination of amaranth and brilliant blue in wine was developed. The effects of different buffer types, pH and concentration of running buffer and or- ganic additives on the separation were investigated. A 50 cm × 75μm uncoated capillary was used with 10 mmol/L citric acid and 5 mmol / L beta-cyclodextrin （pH 2.6） as separation buffer. The detection wavelength was set at 220 rim, and the run voltage was 20 kV. The injection time was 3 s at 20 kPa and the temperature was at room temperature. The linear rela- tionship between the mass concentration of the amaranth and brilliant blue was obtained in the concentration range of 2-200 mg/ L. The limits of detection were 0.58 and 0.50 mg / L for amaranth and brilliant blue, respectively. Their correlation coefficients were not less than 0.999 4. The recoveries were between 93.9% and 107.2%. There was no sample pretreatment in the method. The results showed that the method is simple, accurate, and suitable for the determination of real samples.