离子色谱法测定牛奶中硫氰酸根含量

Determination of Thiocyanate in Milk by Ion Chromatography

建立乳品中硫氰酸根离子测定的离子色谱检测方法,采用IonPac AS 16型阴离子分析柱4 mm×250 mm(配备IonPac AG 16型阴离子保护柱4 mm×50 mm),以KOH为淋洗液,样品经乙腈沉淀蛋白,经水稀释,过滤膜和RP柱后进样,进入电导检测器进行检测,外标法定量.结果表明:本方法中,硫氰酸根浓度在0.02~1.0μg·mL-1时,线性关系良好,相关系数R2为0.9998,回收率在96.0%~99.0%,RSD为0.97%~1.89%,检出限为0.25 mg·kg^-1,定量限为0.75 mg·kg^-1.本文建立了科学、快速、准确测定牛奶中硫氰酸根含量的方法.

A determination method was established for thiocyanate content in milk by ion chromatography.The IonPac AS 16 anion analysis column 4 mm×250 mm(equipped with IonPac AG 16 anion protection column 4 mm×50 mm)and the KOH eluent system was used.The sample was precipitated by acetonitrile,diluted by water,filtered by membrane and RP column,and then injected into conductivity detector for detection.External standard method was used for quantitative analysis.In the range of 0.02~1.0μg·mL^-1,the method had good linearity,the correlation coefficient was R2=0.9998,Thiocyanate recovery was between 96.0%~99.0%,RSD was between 0.97%~1.89%,the method detection limit was 0.25 mg·L^-1,and the quantitative limit was 0.75 mg·kg^-1.A scientific rapid and accurate method for the determination of thiocyanate in milk was established.The method with simple pretreatment can be easily operated.It is suitable for the determination of thiocyanate in milk.