沸水阻断多聚磷酸盐分解离子色谱法检测水产品中的多聚磷酸盐

多聚磷酸盐在水产品中的快速分解影响其准确测定.用沸水破坏使多聚磷酸盐分解的物质,并用三氯甲烷去除水产品中蛋白质等杂质,离子色谱准确测定多聚磷酸盐各组分的量.实验中采用淋洗液自动发生器产生的KOH溶液作为流动相,保护柱和分离柱采用Ionpac AG11-HC和Ionpac AS11-HC抑制电导检测,可以较好地分离所检测焦磷酸根和三偏磷酸根.该方法操作简单,检出限为10 mg/kg,当水产品中添加多聚磷酸盐标准物质浓度达到10～1000 mg/kg范围时,回收率在70%～110%之间,相对标准偏差小于12% .

Determination of Polyphosphates in Aquatic Products by Ion Chromatography after Inhibition by Boiling Water

Due to the rapid decomposition of polyphosphates in aquatic products,it is hard to detect the amount of polyphosphates in aquatic products.In this method,boiling water was used to destroy the substances that induce the decomposition of polyphosphates.In order to remove the impurity,trichloromethane was used as the precipitator.The KOH solution was used as eluent,Ionpac AG11-HC guard column,Ionpac AS11-HC separator column and suppressed conductivity detector were used for the analysis of pyrophosphate,tripolyphosphate and trimetaphosphate.This method is simple and the detection limit is 10.0 mg/kg.The recoveries are 70%-110% for the spiked sample at the concentration level between 10-1000 mg/kg with the RSD less than 12%.