CRM Chromium (Cr) - Aqueous calibration solution ASTASOL® AN901310N

Significance of the Topic

This certificate describes a high-purity aqueous calibration solution of chromium (Cr) designed for critical use in analytical chemistry workflows. Certified reference materials (CRMs) like this one are essential to ensure accuracy, traceability, and comparability of measurements across laboratories and techniques, particularly in environmental, pharmaceutical, food, and industrial quality control contexts.

Objectives and Overview of the Certificate

The document aims to provide:

• An unequivocal statement of the certified chromium concentration and its uncertainty.
• Details on production, homogeneity, and stability assessments.
• Instructions for proper storage, handling, and use in calibration and validation of methods such as AAS, AES, ICP-OES, ICP-MS, molecular absorption, and electroanalytical techniques.

Methodology and Instrumentation

Production and certification rely primarily on gravimetric preparation to ensure SI traceability to the kilogram. Verification and characterization steps include:

• Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES) for concentration confirmation.
• Inductively Coupled Plasma Mass Spectrometry (ICP-MS) for ultra-trace impurity screening.
• Atomic Absorption Spectrometry (AAS) to cross-validate trace element content.
• Use of an independent reference solution (NIST SRM 3112a) to verify chromium values.

Main Results and Discussion

Key certified properties at 20 °C are:

• Density: 1.0430 ± 0.0005 g/cm3.
• Chromium concentration: 10 000 ± 20 mg/L (9 587 ± 30 mg/kg).

Trace impurity profiling demonstrates that all other elements remain below detection or presented at sub-ppm levels. Homogeneity testing confirms negligible bottle-to-bottle variation and stability studies ensure the CRM retains performance over its 5-year shelf life when stored between 5–30 °C and maintained at 20 ± 0.5 °C prior to use.

Benefits and Practical Applications

The certified chromium solution enables laboratories to:

• Calibrate analytical instruments with a SI-traceable standard.
• Validate method performance and accuracy across spectrometric and electrochemical techniques.
• Maintain compliance with regulatory requirements for trace metal analysis.
• Reduce measurement uncertainty through use of a well-characterized CRM.

Future Trends and Applications

Emerging developments likely to enhance reference material utility include:

• Expansion of ultra-trace certifications for additional critical analytes in complex matrices.
• Integration of digital certificates with blockchain for secure traceability.
• Development of multi-element CRMs targeted at high-throughput screening workflows.
• Advances in stability modeling to extend shelf life under variable field conditions.

Conclusion

This CRM offers a rigorously characterized, SI-traceable source of chromium for broad analytical applications. Its certified values, low uncertainty, documented homogeneity, and clear handling protocols make it a cornerstone for accurate calibration and validation in modern laboratories.