Membrane filtration of Sudan orange G on a cellulose acetate membrane filter for separation–preconcentration and spectrophotometric determination in water, chili powder, chili sauce and tomato sauce samples

A simple membrane filtration procedure for separation–enrichment of Sudan orange G is presented. The method is based on the adsorption of Sudan orange G on a cellulose acetate filter and its elution from the membrane with 10 mL of ethanol. Sudan orange G in the eluent was determined by UV–visible spectrophotometry at 388 nm. The effect of analytical conditions, including pH, flow rates and eluent, sample volume, type of membrane for quantitative preconcentration and separation of Sudan orange G were examined. The influences of matrix components on Sudan orange G recoveries were studied. The preconcentration factor was 125. The detection limit was 4.9 μg L−1. The relative standard deviation was 4.3%. The presented procedure was applied to chili powder, chili sauce, tomato sauce, powdered beverage and water samples.