Accurate and reliable analysis of food samples using ICP-MS

Importance of the Topic

Food safety and regulatory compliance require sensitive and reliable quantification of essential and toxic elements across diverse food matrices. Inductively coupled plasma mass spectrometry (ICP-MS) combined with argon gas dilution (AGD) addresses matrix effects and supports strict regulatory limits globally.

Goals and Study Overview

This study aims to develop and validate a single robust ICP-MS method with AGD for simultaneous analysis of macro- and trace elements in various food and beverage samples. Continuous evaluation over multiple days with certified reference materials (CRMs) and quality control (QC) standards ensures method reliability.

Methodology

A microwave digestion workflow was applied to solid samples, while beverage samples received acid dilution and degassing. Key steps:

• Solid samples: 0.5 g dry weight digested in HNO₃/HCl
• Beverages: degassing and 10× dilution in 2% HNO₃
• Online addition of gold (200 μg·L⁻¹) for mercury stabilization
• Analysis via ICP-MS with direct AGD to minimize matrix suppression

Used Instrumentation

• Thermo Scientific iCAP RQ ICP-MS with argon gas dilution module
• Thermo Scientific Qtegra ISDS software for data acquisition and processing
• Teledyne Cetac ASX-560 autosampler

Main Results and Discussion

The method achieved wide linear dynamic ranges (0.005 μg·kg⁻¹ for Hg to 600,000 μg·kg⁻¹ for Na) and low instrument detection limits for key toxic elements. Over 1608 samples run in 8-10 h daily sequences showed:

• Consistent internal standard recoveries (85–110%) over 11.5 h
• CRM recoveries within 93–114% of certified values across diverse matrices
• No instrument maintenance or tuning needed during two-week tests

Benefits and Practical Applications

This single-method approach provides:

• High throughput with minimal user intervention
• Accurate quantification across nutritional and toxic element concentrations
• Compliance with global food safety regulations

Future Trends and Opportunities

Integration with automated sample preparation and advanced data analytics can further increase throughput and data quality. Coupling with collision/reaction cell technology may extend capability for challenging matrices.

Conclusion

The validated ICP-MS AGD method delivers reliable, sensitive, and reproducible multi-element analysis in food and beverages, meeting regulatory demands and operational efficiency. Its robustness and minimal maintenance make it ideal for high-volume testing laboratories.

References

• Commission Regulation (EC) No 1881/2006 setting maximum levels for contaminants in foodstuffs.
• GB-2762-2017 National Food Safety Standard for Maximum Levels of Contaminants in Foods, China.