CRM Nickel (Ni) - Aqueous calibration solution ASTASOL® AN90381C

Significance of the Topic

Aqueous calibration solutions of nickel play a key role in ensuring accurate, traceable measurements in environmental monitoring, industrial quality control and research laboratories. Certified reference materials (CRMs) like ASTASOL® AN90381C establish confidence in analytical results by providing a well‐characterized standard for method validation and instrument calibration.

Objectives and Overview of the Study

The purpose of this certification was to develop and certify an aqueous nickel standard solution in 2% hydrochloric acid, in accordance with ISO Guide 31. The study aimed to achieve direct SI traceability, assign a reliable concentration value with associated uncertainty, and document stability, homogeneity and usability parameters.

Methodology

• Gravimetric preparation using high-purity nickel metal (99.995%).
• Direct traceability to the SI unit kilogram via precise weighing procedures.
• Verification of certified concentration by complexometric titration against NIST SRM 928.
• Cross-validation through independent determination of nickel versus NIST SRM 3136.

Used Instrumentation

• Atomic absorption spectrometry (AAS) for primary and impurity analyses.
• Atomic emission spectrometry (AES) techniques.
• Inductively coupled plasma–optical emission spectrometry (ICP-OES).
• Inductively coupled plasma–mass spectrometry (ICP-MS).
• Molecular absorption spectrometry and selected electroanalytical methods for application suitability.

Main Results and Discussion

The certified nickel concentration in the solution is 1 000 mg/L with an expanded uncertainty of ±2 mg/L (k = 2) at 20 °C, corresponding to 990 mg/kg ±3 mg/kg by mass fraction. The solution density is 1.0099 g/cm3 ±0.0005 g/cm3 at 20 °C. Homogeneity tests confirmed uniform distribution of nickel across production batches. Stability studies guarantee integrity over a five-year unopened shelf life and 12 months after first opening, provided storage and handling conditions are met. Trace impurities for over 70 elements were determined, all below analytical detection limits or at very low temporary levels, ensuring the solution’s high purity for calibration use.

Benefits and Practical Applications

• Accurate calibration of AAS, AES, ICP-OES and ICP-MS instruments for nickel quantification.
• Validation of analytical methods in environmental, industrial and research laboratories.
• Quality assurance support in regulatory testing and compliance programs.

Future Trends and Potential Applications

Advances may include development of multi-element calibration solutions in various matrices, digital-ready CRMs with embedded metadata, and automated stability monitoring. Expansion of such CRMs to cover emerging analytes and novel analytical platforms will further enhance laboratory capabilities.

Conclusion

ASTASOL® AN90381C provides a high-purity, SI-traceable nickel calibration standard with well-defined uncertainty, robust homogeneity and stability profiles. Its comprehensive characterization supports reliable analytical measurements across a wide range of spectrometric and electroanalytical methods.

References

1. ISO Guide 31: Reference Materials – Contents of Certificates and Labels.
2. NIST SRM 928: Complexometric Titration Standard for Nickel.
3. NIST SRM 3136: Nickel Standard Solution for ICP Applications.