基于在乙酸铵缓冲液中3,4-二羟基甲亚胺-H与硼发生显色反应,建立硼的流动注射分光光度自动分析方法。优化试验表明,检测波长430 nm,进样体积500μL,CTMAB对显色反应具有增敏作用。在确定的条件下,方法的线性范围50.0¹ 000.0μg·L-1,相对标准偏差(RSD)1.82%,检出限26.0μg·L-1。实测食品样品中的硼,加标回收率97.5%~104.8%。

The paper proposes a flow injection spectrophotometric method for determining borax in foods. The method is based on the chromogenic reactions of boron and 3,4-dihydroxyazomethineH within the buffer solution of ammonium acetate. Chemical factors and FIA variables affecting the system are discussed. The experiment shows the optimal conditions are that the detected wavelength is 430 nm,sample volume is 500 μL,and CTMAB has sensitizing effect. Under the optimal conditions,the linear range of this method is 50.0-1 000.0 μg·L-1,the detection limit is 26.0 μg·L-1,and the relative standard deviation(RSD) is 1.82%. When the proposed method was applied to determine borax in food,the recoveries were between 97.5% and 104.8%.