CRM Iron (Fe) - Aqueous calibration solution ASTASOL® ANS019

Importance of the topic

This certificate describes a high-purity aqueous calibration solution for iron (Fe) at 1 000 mg/L with an expanded uncertainty of ±5 mg/L (k=2). Reliable reference materials are essential for accurate calibration and validation of analytical methods in laboratories, ensuring traceable and comparable results across different instruments and sites.

Objectives and overview of the certificate

The document aims to provide all critical information on the production, characterization, and proper use of the ASTASOL® ANS019 iron standard solution. It defines the certified value, uncertainty, traceability, homogeneity, stability, storage conditions, and intended applications for analytical techniques.

Methodology and instrumentation

Production and Characterization

• Gravimetric preparation using high-purity Fe metal (99.99+ %) ensures direct traceability to the SI unit (kg).
• Verification of certified value and uncertainty by complexometric titration against SRM NIST 928 and by instrumental methods (AAS, AES, ICP-OES) using a short, unbroken calibration chain with CRM AN90191N.

Instrumental techniques: AAS (atomic absorption spectrometry), AES (atomic emission spectrometry), ICP-OES (inductively coupled plasma optical emission spectrometry).

Main results and discussion

The certified concentration of iron is 1 000 mg/L with an expanded uncertainty of ±5 mg/L at 20 °C. Trace impurities are limited to a maximum of 0.5 mg/L total. Homogeneity studies confirm negligible bottle-to-bottle variation. Stability testing guarantees performance over a five-year shelf life if stored between 5 °C and 30 °C and used under recommended conditions.

Benefits and practical applications

The ANS019 solution is tailored for calibration and validation of analytical methods analyzing aqueous samples in:

• Atomic spectrometry (AAS, AES, ICP-OES)
• Molecular absorption spectrometry
• Electroanalytical techniques

Its high purity and strict traceability support quality assurance in industrial, environmental, and research laboratories.

Future trends and potential applications

Advances may include multi-element calibration solutions, digital certification with blockchain for enhanced traceability, miniaturized CRMs for micro-analysis, and integration with automated sampling systems. Development of CRMs addressing emerging analyte matrices (e.g., nanomaterials) will further broaden analytical capabilities.

Conclusion

ASTASOL® ANS019 offers a robust, SI-traceable calibration standard for iron in aqueous media. Its thorough characterization, stability, and ease of use make it a valuable tool for ensuring reliable analytical results across various spectrometric and electroanalytical methods.