| An improved HPLC-HG-AFS method was developed for determination of inorganic arsenic in rice, in which the effects of particle size, extractants, temperature and extracting methods on the extraction efficiency for arsenic and different mobile phase materials for chromatography column were studied. The optimized conditions of sample pre-treatment and chromatography column were as follows:the rice sample was grinded and sieved by 0.45 mm-mesh, then extracted with the methanol/water solution (V：V=50：50) containing 0.02mol/L HNO3 in a water bath at 95℃for 60 min; 5 mmol/L malonate or 15 mmol/L (NH4)2HPO4 could be chosen as the liquid phase. The results showed that the extraction efficiency was more than 85%, and the recovery were 85% ~110% with the RSD＜10%, and the LOD of the method was 8 滋g/kg. By the method of HPLC-HG-AFS, inorganic arsenic in rice certified reference materials and real rice samples from markets could be detected accurately. |
