螯合萃取石墨炉原子吸收光谱法测定食品中的砷

Determination of Arsenic in Food by Chelate Extraction and Graphite Furnace Atomic Absorption Spectrometry

采用石墨炉原子吸收技术研究了食品中砷的测定方法。选择ＡＰＤＣ－ＭＩＢＫ萃取分离体系使砷与基体分离；采用硝酸镁＋硝酸镍作混合基体改进剂，将灰化温度提高到１１００℃，消除了共存阴、阳离子的干扰。方法检出限１．６ｎｇ／ｍｌ，２ｇ样品的最低检出浓度为６．０ｎｇ／ｇ，相对标准偏差小于１４％，平均加标回收率为９９．１±６．９％。本法具有干扰少，灵敏度高等特点。

A method for determination of As in food by graphite furnace atomic sbsorption spectrometry has been developed. Using APDC MIBK extraction system and Mg(NO 3) 2+Ni(NO 3) 2 as a matrix modifier, the chartemperature can be raised to 1 100℃. Possible interferences from cations and anions have been eliminated.The limit of detection is 1.6 ng/ml, the lowest detection concentration of 2 g sample is 6.0 ng/g , R.S.D. is <14% and the recovery is 99.1±6.9%. The suggested method have a high sensitivity and few interference.