Rapid determination of metallothioneins in foods by capillary zone electrophoresis

A rapid method for the analysis of metallothioneins(MT) in foods by capillary zone electrophoresis(CZE) was developed. Two isomers of MT(MT1,MT2) in foods were separated and determined. After a series of optimization, the separation and determination of MT1 and MT2 were obtained within 10 min by using the phosphate buffer system consisting of 0.02 mol/L Na_2HPO_4 and 0.02 mol/L NaH_2PO_4 (pH 7.0), and UV detection at 200 nm. Under the optimal experimental conditions, the minimum detectable limit was 1 mg/L, and the added standard recoveries of MT1, MT2 in foods were found to be in the range of 82.0%-93.4%. The relative standard deviations (RSD) were found to be lower than 10%. Therefore, with this simple and rapid method, the contents of two isomers in foods can be determined by external standard method after sample pretreatment.