SEPARATION AND DETERMINATION OF 4 ARTIFICIAL SWEETENERS AND CITRIC-ACID BY HIGH-PERFORMANCE ANION-EXCHANGE CHROMATOGRAPHY

A high-performance anion-exchange chromatographic method for the simul taneous separation and determination of four artificial sweeteners (so dium saccharin, aspartame, sodium cyclamate and acesulfame-K) and citr ic acid in a single injection is proposed. The separation was performe d by an anion-exchange gradient program and determination by ultraviol et absorbance detection for sodium saccharin, aspartame, acesulfame-K in combination with conductivity detection for sodium saccharin, sodiu m cyclamate, acesulfame-K as well as citric acid in series. Good linea rities between the concentrations of all analytes and relevant peak ar ea responses were achieved over the range 2-100 mu g/ml. The detection limits (signal-to-noise ratio 3:1) were 0.019 mu g/ml for sodium sacc harin, 0.035 mu g/ml for aspartame, 0.044 mu g/ml for acesulfame-K by ultraviolet absorbance detection and 0.26 mu g/ml for sodium saccharin , 0.16 mu g/ml for sodium cyclamate, 0.23 mu g/ml for acesulfame-K and 0.22 mu g/ml for citric acid by conductivity detection. The method ha s been successfully applied to the determination of the four sweetener s and citric acid in drinks and powdered tabletop sweeteners, and the average recoveries for various samples ranged from 93 to 107%.