Determination Of Food Additives In Beverage By Capillary Electrophoresis

Capillary electrophoresis (CE) is a new technique of separation, which has raised worldwide interest during recent years. The main advantages of CE compared with high performance liquid chromatography (HPLC) are the high efficiency, fast separation, low instrumental cost, and low consumption of samples and reagents. In this paper, we have used capillary electrophoresis to developed new analytical methods for food additives in soft drink.The thesis consists of four chapters.In first chapter, a review about capillary electrophoresis, the application of capillary electrophoresis in soft drink analysis, studies about food safety were summarized in detail according to the articles in recent years. And in this part, we described our aim and purpose.Chapter two is study of new analytical method for five food additives (Ⅰ) with HPCE. Excessive food additives has been found in food products and caused panic among customers. High performance capillary electrophoresis (HPCE) with UV detector was proposed to determine the food additives. Through study of different solution, pH, voltage, the separation of a mixture of the standards (five food additives (Ⅰ)) was achieved under the conditions that the background electrolyte is20mmol/L Na2B4O7-20mmol/L H3BO3, pH=9.0, wavelength is211nm and applied voltage is20kV. Five food additives (Ⅰ) were separated with range from5-500mg/L. The results demonstrate the applicability of the method to determination of Caffeine, Aspartame, Potassium sorbate, Sodium benzoate, Acesulfame Potassium.Chapter three is study of new analytical method for five food additives (Ⅱ) with HPCE. Through study of different solution, pH, voltage, the separation of a mixture of the standards (five food additives (Ⅱ)) was achieved under the conditions that the background electrolyte is20mmol/L Na2B4O7-20mmol/L H3BO3, pH=9.0, wavelength is242nm and applied voltage is20kV, five food additives (Ⅱ) were separated with range from20-1000mg/L. The results demonstrate the applicability of the method to determination of Caffeine, Ascorbic acid, Potassium sorbate, Sodium benzoate, Acesulfame Potassium.Chapter four is study of new analytical method for eight colorants with HPCE. Through study of different solution, pH, voltage, the separation of a mixture of the standards (eight colorants) was achieved under the conditions that the background electrolyte is10mmol KH2PO4-3mmol Na2B4O7,pH=11.0, wavelength is211nm and applied voltage is20kV, eight colorants were separated with range from2-50mg/L. The results demonstrate the applicability of the method to determination of brilliant blue, lissamine green B, allura red, sunset yellow, ponceau-4R, carmoisine, amaranth, tartrazine.