毛细管电泳法直接分离测定果冻中的色素

Direct Separation and Determination of Synthetic Pigments in Jelly by Capillary Electrophoresis

建立毛细管电泳法直接测定果冻中亮蓝、胭脂红、柠檬黄的方法,研究缓冲溶液种类、浓度、pH值、电压等对分离的影响,并对分离条件进行优化。在波长255nm、分离电压18kV、pH8.5、5mmol/L Na2HPO4-5mmol/LNa2B4O7溶液中,亮蓝、胭脂红、柠檬黄在6min内得到了较好的分离。用于部分市售果冻样品的测定,得到较满意结果,回收率为85%～110%。

A method was developed for the direct determination of brilliant blue, ponceau 4R and tartrazine in jelly by capillary electrophoresis. The effects of several factors, such as pH value, type and concentration of running buffer, separation voltage on the separation of the synthetic pigments were investigated to f＇md optimum conditions. The best separation among brilliant blue, ponceau 4R and tartrazine was achieved within 6 rain under the following conditions： a mixture of 5 mmol/L Na2HPO4 and 5 mmol/L Na2B407 （pH： 8.5） as running buffer, separation voltage 18 kV, and detection wavelength 255 nm. The method has been used to determine some commercial jellies with satisfying results and recovery rates between 85% and 110%.