高效液相色谱-氢化物发生原子荧光联用法检测 不同基质食品中的砷含量及其形态

目的建立高效液相色谱-氢化物发生原子荧光联用法检测大虾、金枪鱼、虾油、大米和菠菜等不同基质食品中的砷含量及其化学形态。方法将大虾、金枪鱼、虾油、大米和菠菜样品采用HNO_3(0.15 mol/L)浸提,高效液相色谱-氢化物发生原子荧光联用法进行砷形态的研究,并用湿法消解-原子荧光光谱法进行总砷含量的测定。结果所测大虾、金枪鱼、虾油、大米、菠菜样品总砷含量为0.23~4.68 mg/kg,有机砷含量为0~3.9 mg/kg。海产品中主要砷形态为2种砷化物:二甲基砷(DMA)和砷甜菜碱(AsB);大米及菠菜样品中主要的砷形态为:三价砷As(Ⅲ)、二甲基砷(DMA)和五价砷As(Ⅴ)。结论该方法操作简单,灵敏度高,重现性好,适用于食品中砷形态含量的定量检测。

Determination of arsenic content and speciation in foods of different matrixes by high performance liquid chromatography-hydride generation atomic fluorescence spectrometry

Objective To establish a method for the determination of total arsenic and chemical speciation in prawn, tuna, shrimp sauce, rice and spinach of different matrixes by high performance liquid chromatography-hydride generation atomic fluorescence spectrometry(HPLC-HG-AFS). Methods After extracting the samples with HNO3 (0.15 mol/L), the chemical speciation of arsenic was studied by HPLC-HG-AFS and the content of total arsenic was determined by atomic fluorescence spectrometry (AFS) after wet digestion. Results The total arsenic content in prawn, tuna, shrimp, rice, spinach ranged from 0.23 to 4.68 mg/kg, and organic arsenic content ranged from 0 to 3.9 mg/kg. There were 2 kinds of main arsenic speciation compounds in marine products: DMA and AsB, both were low toxic organic arsenic species. The main arsenic species in rice and spinach were As (III), DMA and As(V). Conclusion This method is effective to determine arsenic species for its high sensitivity and reproducibility.