CRM Chlorides (Cl-) - Aqueous calibration solution ASTASOL® AN90721H

Importance of the Topic

Aqueous calibration solutions are fundamental tools in quantitative analysis across laboratories. Certified reference materials (CRMs) for chloride determination support method calibration, validation, and routine quality control in atomic spectrometry, ion chromatography and electroanalytical techniques. Reliable chloride standards underpin accurate environmental, pharmaceutical, industrial and food analysis.

Aims and Overview of the Certificate

This document presents the certification of ASTASOL® AN90721H, an aqueous chloride CRM produced by Analytika, spol. s r.o. Key objectives include providing traceable, homogeneous and stable chloride solutions with stated concentration and uncertainty, compliant with ISO Guide 31 and ISO 17034.

Methodology and Instrumentation

The CRM was prepared gravimetrically using high-purity KCl (99.997%) dissolved in ultrapure demineralized water. Direct traceability to the SI unit kilogram is achieved through gravimetry. Certified chloride concentration and uncertainty were verified by argentometric titration. Trace impurities (Br⁻, F⁻, I⁻, NO₂⁻, NO₃⁻, PO₄³⁻, SO₄²⁻) were quantified by ion chromatography as informational values.

Main Results and Discussion

• Certified chloride concentration: 1 000 ± 2 mg/L (expanded uncertainty, k=2) at 20 °C, equivalent to 1 001 ± 3 mg/kg.
• Solution density: 0.9994 ± 0.0005 g/cm³ (20 °C, k=2).
• Impurity levels below detection limits (<0.02 mg/L for most anions; SO₄²⁻ <0.05 mg/L).
• Homogeneity tests and stability assessments confirm consistency over a five-year shelf life when stored at 5–30 °C.

Benefits and Practical Applications

• Supports calibration and validation of AAS, AES, ICP-OES, ICP-MS, molecular absorption and ion chromatography methods.
• Assures traceability and comparability of chloride measurements across laboratories.
• Facilitates compliance with quality management standards (ISO 9001, ISO/IEC 17025, ISO 17034).

Future Trends and Opportunities

Advances may include multi-element aqueous CRMs, automated gravimetric dispensing and integration with digital certificate platforms. Enhanced impurity profiling using high-resolution mass spectrometry could broaden user confidence. Development of matrix-matched and low-level trace analyte CRMs will address emerging regulatory requirements.

Conclusion

ASTASOL® AN90721H offers a rigorously characterized, traceable chloride standard with low uncertainty, validated by established titrimetric and chromatographic methods. Its robust stability and homogeneity make it a dependable tool for analytical calibration and quality assurance in diverse laboratory settings.

Reference

Analytika, spol. s r.o. Certificate of Analysis for ASTASOL® AN90721H, Version 01, June 2023.