Matrix effects of 9 industrial dyes in foods by high performance liquid chromatography with gelpermeation chromatography purification

By gel permeation chromatography purification-high-performance liquid chromatography,the methods were built to measure 9 industrial dyes in foods. The matrix effects of 4 types of foods including ham,sausage,pork and hotpot condiment,were analyzed by standard addition method. The recovery rate were compared between matrix of standard curve and solvent standard curve methods in order to probe the effects of the matrix type,matrix concentration and the industrial dye concentration to matrix effects and find the methods to weaken matrix effects. The results showed that there were good linear relationship between the matrix standard curve and solvent standard curve of 9 industrial dyes in the range of 0.25~4.0 μg/mL. All four kinds of foods had matrix effects of different degrees for 4 types of foods to 9 industrial dyes. The matrix type,matrix concentration and the industrial dye concentration all affected the intensity of matrix effects. By ethyl acetate-cyclohexane(1∶1,v/v)extraction,purified samples extracted by gel permeation extraction weakened the matrix effects to some degree,but matrix effects could not be eliminated.