【摘 要】 本文建立了一种采用离子色谱法，抑制型电导检测器测定奶粉中亚硝酸根和硝酸根的方法。选择的色谱条件是：高容量碳酸盐/氢氧化物双重选择性色谱柱IonPac AS23阴离子交换柱，碳酸钠/碳酸氢钠缓冲溶液等度淋洗，抑制型电导检测。奶粉样品经称重、溶解、提取、蛋白沉降、固相萃取和过滤后进样。该方法检测限(S/N=3)为 61 - 70 ng/g，线性相关系数r=0.9999，实际样品RSD小于6%，具有灵敏度高，选择性好，操作简单，价格便宜，对环境友好等特点。

    【关键词】 离子色谱 电导法 奶粉 硝酸盐 亚硝酸盐

    Determination of Nitrite and Nitrate in Milk Powder by Suppressed Conductivity Ion Chromatography

    【Abstract】 The present paper developed a method to analyse trace nitrite and nitrate in milk powder by suppressed conductivity ion chromatography. The separation of trace nitrite， nitrace and other anions and orgnic aicds was obtained by using IonPac AS23 anion exchange column which is a carbonate/hydroxide double selectivity column and a carbonate/bicarbonate buffer solution was selected as eluent. The milk powder samples were pretreated iincluding weighting ......