CRM Nickel (Ni) - Aqueous calibration solution ASTASOL® AN90381N

Importance of the topic

A certified reference material (CRM) for nickel in aqueous solution is essential for achieving reliable calibration, validation and interlaboratory comparability in trace metal analysis. Such CRMs support quality assurance in environmental monitoring, industrial process control and research applications where precise quantification of nickel at the mg/l level is critical.

Objectives and study overview

This certificate describes the properties and intended use of ASTASOL AN90381N, an aqueous calibration solution containing nickel at a certified concentration of 1000 mg/l. The goal is to provide a fully characterized CRM with defined uncertainty and traceability to the SI unit, suitable for calibration of atomic and molecular spectrometric techniques as well as selected electroanalytical methods.

Methodology

The nickel solution was prepared gravimetrically using high-purity nickel metal (99.995 %) dissolved in 2 % nitric acid. Traceability to the kilogram was established through the weighing procedure. Characterization included complexometric titration against SRM NIST 928 and independent verification via comparison with SRM NIST 3136. Homogeneity and stability studies confirmed consistent performance over the shelf life.

Instrumentation

The following analytical techniques were applied:

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

These methods were used to verify the certified nickel concentration and to assess trace impurities at sub-mg/l levels.

Main results and discussion

The certified nickel concentration is 1000 ± 2 mg/l (k=2) at 20 °C, corresponding to 988 ± 3 mg/kg by mass fraction. The solution matrix is 2 % HNO3 in ultrapure water with a density of 1.0120 ± 0.0005 g/cm3. Trace elements were found below detection limits or at low µg/l levels, confirming high matrix purity. Homogeneity tests showed no significant between-unit variation, and stability is guaranteed for five years under 5–30 °C storage, with a 12-month period of use after opening.

Benefits and practical applications

• Ensures SI-traceable calibration for spectrometric and electroanalytical methods
• Supports quality control in environmental, industrial and research laboratories
• Provides documented uncertainty and stability, reducing measurement risk

Future trends and possibilities

Advances may include digital certificates with QR codes for rapid verification, development of matrix-matched CRMs for complex sample types, multi-element aqueous standards, and integration with automated calibration systems. Ongoing improvements in production and characterization techniques will further reduce uncertainties and expand CRM offerings.

Conclusion

ASTASOL AN90381N delivers a thoroughly validated nickel calibration solution with tight uncertainty, full SI traceability and demonstrated stability. It is suitable for high-accuracy determination of nickel in aqueous matrices, facilitating reliable method calibration and interlaboratory consistency.

References

• ISO Guide 31, Reference Materials – Contents of Certificates and Labels
• ISO 17034:2017, General Requirements for the Competence of Reference Material Producers
• SRM NIST 928, Complexometric Standard Solution of EDTA
• SRM NIST 3136, Aqueous Nickel Standard