Qualitative and Quantitative Analysis of Seafood by EDXRF

Importance of X-ray Fluorescence Analysis in Seafood Quality Control

Rapid and non destructive elemental analysis of seafood is critical for monitoring nutritional components and contaminants. Energy dispersive XRF enables direct measurement of trace and major elements in complex organic matrices with minimal sample preparation, supporting food safety, regulatory compliance and quality assurance in the seafood industry.

Objectives and Study Overview

This study evaluates qualitative and quantitative XRF analysis of seaweed and swordfish tissue using two sample preparation methods and two instrument models. Key goals include comparing pressure forming versus manual press, assessing detection limits and quantitation accuracy, and exploring iodine and cesium detection capabilities.

Sample Preparation and Methodology

Standard reference powders of hijiki seaweed and swordfish tissue were used. Two preparation procedures were applied

• Pressure forming: 50 kN for 20 s into vinyl rings yielding dense briquettes
• Easy press: hand pressing of powder over Prolene films in sample cups

Organic matrix was modeled as CH2O for matrix correction. Qualitative scans and fundamental parameter quantitation were performed under optimized voltage and filter settings.

Instrumentation

Analysis employed two EDXRF spectrometers

• EDX 800HS covering elements C to U with Rh tube and multiple filters
• EDX 720 optimized for Na to U with selectable filters for L and K lines

Measurements used 300 second live time, vacuum atmosphere and collimation to 10 mm diameter.

Main Results and Discussion

Quantitation accuracy for elements above 0.1 mass percent was within 30 percent error. Sodium under 1 percent showed 50 percent error. Trace elements below 0.1 percent were within a factor of two. Pressure forming enhanced sensitivity for light elements Na to Ca. Comparative analysis of I and Cs spikes revealed K line detection is more reliable for adjacent atomic numbers. Lower limits of detection improved for major elements under briquette preparation and were influenced by instrument model, with EDX 800HS showing superior LLD for iodine and cesium.

Benefits and Practical Applications

The described XRF workflow enables rapid screening of seafood for nutritional and contaminant elements without extensive digestion or wet chemistry. Flexible preparation methods suit high throughput quality control and certification of food products.

Future Trends and Potential Applications

Advances in detector technology and portable XRF instruments will extend in situ analysis capabilities. Integration with chemometric tools can improve quantitation in diverse food matrices. Expanding certified reference materials will support method validation for emerging contaminants.

Conclusion

XRF analysis of seafood using optimized sample preparation and instrument configurations offers a reliable, efficient approach for routine monitoring of elemental composition. The combination of pressure forming and fundamental parameter methods ensures broad applicability in laboratory and field settings.

References

Application note LAAN A XR E021A Shimadzu Corporation
NMIJ Certified Reference Materials for seaweed and fish tissue