[Capillary zone electrophoretic determination of NaFeEDTA in iron fortified soy sauce].

Objective: An analytical method for separation and determination of sodium iron (III) ethylenediaminetetraacetate (NaFeEDTA) in iron fortified soy sauce by capillary zone electrophoresis (CZE) has been developed.

Methods: The electrolyte, which contains 30 mmol/L citric acid, 20 mmol/L Tris, 0.15 mmol/L CTAB and 0.05 mmol/L SDS, was used to improve the peak shape and reduce the retention time at the voltage of - 25.0 kV. The sample can be determined at UV 254 nm after diluted.

Results: In this method, which enjoyed a wide linear range and good precision, the RSD (n = 6) was 2.15%, the average recoveries for samples ranged from 94.3% - 101.2% and the detection limit of the NaFeEDTA in iron fortified soy sauce is 4 microg/ml (S/N = 3).

Conclusion: The results of application of different kinds of soy sauce showed that the method was direct, accurate, fast and simple.