Rapid sample preparation procedure for As speciation in food samples by LC-ICP-MS

Abstract

This paper describes a rapid method for arsenic (As) speciation by LC-ICP-MS in several types of food samples. Prior to analysis, samples were milled and the As species extracted from biological tissues by sonication in only 2 min with a solution containing MeOH (10%, v/v) plus HNO₃ (2%, v/v). As species were separated by LC using an anion exchange column. Method detection limits for AsB, As³⁺, DMA, MMA and As⁵⁺ were 1.3, 0.9, 0.6, 0.7 and 0.8 ng g⁻¹, respectively. Method accuracy and precision were traceable to Certified Reference Materials SRM1577 bovine liver from the National Institute of Standards and Technology, CE278 mussel tissue from the Institute of Reference Materials and Measurements and DOLT-3 dogfish liver tissue and DORM-3 fish protein from the National Research Council of Canada. Finally, the method was applied to speciate As in food samples (egg, fish muscle, beef and chicken) purchased in Brazilian markets.

Keywords:

• chromatography – LC/MS
• ICP/MS
• metals analysis – ICP/MS
• heavy metals – arsenic
• metals speciation
• animal products – meat
• canned foods
• eggs
• fish and fish products

Acknowledgements

The authors would like to acknowledge the financial support of the São Paulo State Foundation for Scientific Research (FAPESP, Brazil); and thank the Brazilian National Council for Scientific and Technological Development (CNPq) and the Foundation for the Coordination of Improvement of Higher Education Personnel (CAPES) for fellowships.