Robust single method determination of major and trace elements in foodstuffs using the Thermo Scientific iCAP 7400 ICP-OES Duo

Significance of the Topic

The safety and nutritional quality of foodstuffs is critically dependent on reliable detection of both essential micronutrients and potentially toxic contaminants. Regulatory bodies such as the Codex Alimentarius Commission establish food standards worldwide, driving the need for analytical methods that combine sensitivity, accuracy, and robustness to support public health and compliance.

Objectives and Study Overview

This study demonstrates a unified approach for simultaneous determination of major and trace elements in diverse food matrices using the Thermo Scientific iCAP 7400 ICP-OES Duo. The method aims to meet regulatory requirements while delivering precise quantification of elements such as Ca, Cu, Fe, Mg, Mn, Ni, P and Zn.

Used Instrumentation

The analysis was performed on the Thermo Scientific iCAP 7400 Duo ICP-OES featuring a high resolution echelle spectrometer and a charge injection device detector. Axial and radial plasma viewing modes were selected to optimize sensitivity and matrix tolerance. Key instrument settings included RF power 1150 W, nebulizer gas flow 0.6 L·min-1, coolant gas flow 12 L·min-1, and UV and visible exposure times of 15 s and 5 s respectively.

Methodology and Sample Preparation

Samples comprising a total diet, wheat flour and bovine liver certified reference materials were digested using microwave-assisted acid digestion (HNO3 and HCl). Calibration standards were prepared from high purity single element solutions, covering concentration ranges from 0.1 to 50 mg·kg-1, and matrix matched to the sample digest composition. Quality control was managed through integrated checks, flags and limits in the Qtegra ISDS software.

Main Results and Discussion

Quantitative analysis yielded recoveries between 95 and 105 for all elements, demonstrating excellent accuracy against certified reference values. Method detection limits ranged from 0.01 mg·kg-1 for Mn to 4.3 mg·kg-1 for Fe. The combination of axial and radial views enabled low detection limits and minimized spectral interferences.

Benefits and Practical Applications

• Single method covers a broad range of major and trace elements
• High sensitivity and low detection limits support regulatory compliance
• Robust performance across complex food matrices
• Integrated software quality control enhances reliability and throughput

Future Trends and Potential Applications

Advancements may include further automation of sample preparation, expansion to additional elements and isotopes, integration with data analytics for real time decision making, and development of portable ICP-OES systems for field testing.

Conclusion

The iCAP 7400 ICP-OES Duo provides a powerful, reliable platform for comprehensive analysis of macro and trace elements in foodstuffs. Its combination of detector sensitivity, versatile viewing modes and advanced software makes it well suited for routine QA/QC and regulatory applications.