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

Significance of the Topic

Ensuring the safety and nutritional quality of food involves accurate measurement of both essential micronutrients and potentially toxic contaminants. Regulatory bodies such as the Codex Alimentarius Commission set globally accepted limits for major and trace elements in food. A reliable, single analytical method that can quantify a wide range of elements in diverse food matrices helps laboratories meet compliance requirements efficiently.

Goals and Overview of the Study

This application note evaluates the performance of the Thermo Scientific iCAP PRO X Duo ICP-OES for simultaneous determination of major elements (Ca, Mg, P) and trace elements (Cu, Fe, Mn, Ni, Pb, Zn) in food samples. Certified reference materials (rice flour and bovine liver) are used to demonstrate method accuracy, detection limits, and compliance with food safety regulations.

Methodology

Samples (0.5 g) of reference materials were digested in nitric acid using a high-pressure microwave system. Digests were diluted to 50 mL with deionized water. Calibration standards covering the expected concentration ranges were prepared from 1000 mg·kg⁻¹ single-element solutions and matched in acid matrix. Analysis employed an acid rinse between samples to prevent carryover.

Used Instrumentation

The key analytical setup included:

• Thermo Scientific iCAP PRO X Duo ICP-OES with high-resolution Echelle optics and a charge injection device (CID) detector covering 167–852 nm in a single exposure.
• Qtegra ISDS Software for data acquisition, quality control checks, automated flagging, and post-analysis data processing.
• Glass concentric nebulizer, cyclonic spray chamber, and sample pump at 45 rpm.

Main Results and Discussion

Calibration exhibited linear response for all elements. Recoveries for certified reference materials ranged from 90 % to 105 % across major and trace elements. Method detection limits (MDLs) were in the low µg·kg⁻¹ range (e.g., Mn: 0.04 µg·kg⁻¹, Pb: 2.9 µg·kg⁻¹), demonstrating high sensitivity. Dilutions were applied for over-range analytes to maintain accuracy.

Benefits and Practical Applications

• Single-method, multi-element analysis reduces sample preparation time and resource use.
• Wide dynamic range accommodates both high-level nutrients and trace contaminants.
• Automated QC features ensure data integrity for regulatory compliance.

Future Trends and Opportunities

Advances in detector technology and software integration will further lower detection limits and streamline workflows. Emerging trends include green digestion techniques, automation of sample handling, and application of machine learning for spectral interference removal and predictive maintenance of instrumentation.

Conclusion

The Thermo Scientific iCAP PRO X Duo ICP-OES provides a robust, sensitive, and efficient solution for simultaneous determination of major and trace elements in food matrices. Its full-spectrum capability, low detection limits, and integrated QC make it well suited for routine food safety testing.

Reference

Thermo Fisher Scientific. Application Note 44423: Robust single method determination of major and trace elements in foodstuffs using the Thermo Scientific iCAP PRO X Duo ICP-OES.