Simultaneous determination of five arsenic species in infant rice flour by microwave extraction-liquid chromatography-inductively coupled plasma mass spectrometry

Abstract

ObjectiveA pretreatment method based on microwave extraction combined with liquid chromatography-inductively coupled plasma mass spectrometry （LC-ICPMS） was established to accurately determine the five arsenic speciations of arsenobetaine （AsB）， arsenite （As （Ⅲ））， dimethyl arsenate （DMA）， monomethyl arsenate （MMA） and arsenate （As （Ⅴ）） in infant rice flour.MethodsThe samples of infant rice flour were extracted with 1% HNO3 and microwave extraction at 90 ℃ for 60 min， centrifuged through the membrane， and the extract was analyzed quantitatively by LC-ICPMS.ResultsThe established method showed good linear relationships in the range of 0.1-50 μg/L with the coefficient of determination R2>0.999 9 for the five arsenic species. The recoveries at different spiked levels were 95.20%-102.00%， and the intra day and inter day precision was less than 5%. The limits of detection of the method were 0.006-0.012 mg/kg.ConclusionThe microwave extraction pretreatment method was simple and fast， and the quantitative analysis was sensitive and accurate， which was suitable for the determination of arsenic species in infant rice flour samples.

Keywords

• arsenic speciation analysis
• microwave extraction
• liquid chromatography-inductively coupled plasma mass spectrometry
• infant rice flour