CRM Magnesium (Mg) - Aqueous calibration solution ASTASOL® ANS232

Importance of the topic

Aqueous calibration solutions with certified reference values are fundamental tools in analytical chemistry. They ensure traceable, accurate and reproducible quantification of target analytes in various matrices. High-purity magnesium calibration solutions support the validation and calibration of techniques such as atomic absorption spectrometry (AAS), atomic emission spectrometry (AES) and inductively coupled plasma optical emission spectrometry (ICP-OES), which are widely employed in environmental monitoring, pharmaceutical analysis and quality-control laboratories.

Objective and study overview

The certificate for ASTASOL® ANS232 details its role as a certified reference material (CRM) for magnesium in aqueous solution. It establishes metrological traceability, concentration assignment and uncertainty evaluation to support accurate method calibration and validation. The document outlines production, characterization, storage requirements and intended analytical applications.

Methodology and Instrumentation

The magnesium concentration of 10 000 mg/L ±50 mg/L (k=2) at 20 °C was established by gravimetric preparation using high-purity Mg metal (99.98 %). Traceability to the SI unit (kilogram) was secured through direct mass measurements. Verification involved:

• Complexometric titration
• Atomic absorption spectrometry (AAS)
• Atomic emission spectrometry (AES)
• Inductively coupled plasma optical emission spectrometry (ICP-OES)

Homogeneity and stability studies confirm consistent concentration across production batches and retention of certified value over the five-year shelf life when stored under prescribed conditions.

Main results and discussion

The certified magnesium concentration meets stringent uncertainty requirements (≤0.5 %). Total trace impurities in the solution do not exceed 5 mg/L. Stability testing under controlled temperature (5–30 °C) and handling protocols ensures that concentration and uncertainty remain within certified limits for the shelf life period. Instructions emphasize temperature equilibration to 20 ±0.5 °C before use, avoidance of pipetting directly from the bottle, and minimization of bottle headspace.

Benefits and practical applications

Certified calibration solutions like ASTASOL® ANS232 provide:

• Reliable calibration standards for AAS, AES, ICP-OES and selected electroanalytical methods
• Traceable results aligned with international standards (ISO Guide 31, ISO 17034)
• Reduced measurement uncertainty and improved method validation
• Enhanced comparability across laboratories and over time

They are critical in laboratories requiring regulatory compliance, quality assurance and high-confidence data in research and industrial processes.

Future trends and applications

Continuous improvement of CRM production focuses on narrower uncertainty budgets, extended stability under varied conditions and tailored matrices for complex sample types. Advances include:

• Multi-element calibration solutions for simultaneous determination of several analytes
• Matrix-matched CRMs simulating real sample environments
• Digital certification linked to blockchain for enhanced traceability and authenticity
• Miniaturized and on-site calibration standards for portable spectrometers

Conclusion

ASTASOL® ANS232 provides a high-purity, SI-traceable magnesium calibration standard with well-defined uncertainty and robust stability. It supports accurate method calibration and validation across a range of spectrometric and electroanalytical techniques, ensuring confident decision-making in analytical laboratories.

Reference

• ISO Guide 31: Reference materials — Contents of certificates, labels and accompanying documentation
• ČSN EN ISO 17034:2017 — General requirements for the competence of reference material producers
• ČSN EN ISO/IEC 17025:2018 — General requirements for the competence of testing and calibration laboratories
• ČSN EN ISO 9001:2016 — Quality management systems — Requirements