Solid-Phase Extraction and Large-Volume Sample Stacking-Capillary Electrophoresis for Determination of Artificial Sweeteners in Water Samples

A sensitive and rapid method for the simultaneous analysis of artificial sweeteners, aspartame, acesulfame, cyclamate, saccharine, and phenylalanine in water samples using solid-phase and large-volume sample stacking-capillary electrophoresis (SPE-LVSS-CE) has been developed. Under optimal conditions, the proposed method had a linear range of 0.08 to 2.0mgL(-1), with limits of detection ranging from 0.03 to 0.18mgL(-1) with inter- and intraday repeatabilities <10% (as a relative standard deviation) in all cases. The enrichment factor obtained was in a range from 20 to 89 times for each artificial sweetener compared with a conventional capillary zone electrophoresis (CZE). The method is adequate to analyze artificial sweeteners in water samples with different ionic strengths. The proposed method was employed in the analysis of 20 samples including drinking water such as mineral water, distilled water, spring water, and tap water. Nine of the tested samples were positive for the presence of aspartame, saccharine, and acesulfame with concentrations between 0.19 and 0.75 mgL(-1), 0.08 mgL(-1), and 0.08 mgL(-1), respectively. The SPE-LVSS-CE is a robust, easy, fast, and efficient strategy for online preconcentration of artificial sweeteners in complex matrices.