毛细管区带电泳法分离测定铁强化酱油中乙二胺四乙酸铁钠

目的建立利用毛细管区带电泳(CZE)技术分离测定铁强化酱油中的铁营养强化剂乙二胺四乙酸铁钠(NaFeEDTA)的方法。方法在25kV电压下阳极端检测,采用含有30mmolL柠檬酸、20mmolL三羟甲基氨基甲烷(Tris)、0.15mmolL十二烷基溴化铵(CTAB)和0.05mmolL十二烷基硫酸钠(SDS)的缓冲溶液作为分离介质,254nm紫外检测器检测,样品经稀释后进样分析。结果方法的线性范围广,精密度和准确度高,重复测定(n=6)的相对标准偏差RSD为2.15%,样品平均加标回收率为94.3%～101.2%。NaFeEDTA在铁强化酱油的最低检出限为4μgml(SN=3)。结论使用不同品牌的酱油作为载体对NaFeEDTA的测定没有影响,本方法具有直接、准确、快速、简便等优点。

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.