We developed a capillary zone electrophoresis method with direct UV detection for the determination of inorganic anions (Cl
−, NO
2−, and NO
3−), organic acids (oxalic acid, citric acid, and malic acid), and amino acids (aspartic acid and glutamic acid) in the common ice plant (
Mesembryanthemum crystallinum L.). As the background electrolyte, a 20 mmol L
−1 disodium hydrogenphosphate dodecahydrate solution adjusted to pH 10.6 was used with the addition of 0.001% (w/v) hexadimethrine bromide to reverse electroosmotic flow. The detection responses for the above analytes were improved by 3.5 – 580 fold in terms of the limits of detection (LODs,
S/N = 3) in comparison with conventional indirect UV detection. The LODs for the analytes were 0.040 – 2.9 mg L
−1. The values of the relative standard deviation (RSD,
n = 4, intra-day) of the migration time and the peak area were, respectively, 0.081 – 0.43% and 0.28 – 9.3% when extract from the common ice plant was analyzed. Using the proposed procedure, Cl
−, NO
2−, NO
3−, and oxalic acid in the common ice plant were detected within 9 min; citric acid, malic acid, aspartic acid, and glutamic acid were detected within 12 min.
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