CRM Chlorides (Cl-) - Aqueous calibration solution ASTASOL® AN8072HIC

Importance of the Topic

This certificate describes a highly pure aqueous calibration solution for chlorides, essential for ensuring accurate and traceable results in environmental monitoring, industrial quality control, and clinical or research laboratories. Certified reference materials (CRMs) like ASTASOL AN8072HIC support method validation, instrument calibration, and inter-laboratory comparability.

Objectives and Overview of the Certificate

This document certifies the preparation, characterization, and shelf life of ASTASOL AN8072HIC, a chloride standard produced by Analytika, spol. s r.o. The CRM provides a known concentration of chloride ions, established under ISO Guide 31 and ISO 17034, for robust analytical performance across multiple techniques.

Methodology and Instrumentation

The solution was prepared gravimetrically using high-purity KCl (99.997%) dissolved in ultrapure demineralized water. Key procedures and instrumentation:

• Weighing and preparation traceable to the SI kilogram.
• Membrane ultrafiltration (0.45 µm) to prevent chromatography column clogging.
• Argentometric titration to verify chloride concentration and uncertainty.
• Ion chromatography for characterization of trace impurities (Br–, F–, I–, NO₂–, NO₃–, PO₄³–, SO₄²–).

Main Results and Discussion

Certified concentration and uncertainty (k=2) at 20 °C:

• 100.0 mg/L ± 0.2 mg/L
• 100.0 mg/kg ± 0.3 mg/kg (derived from density)

Density is 0.9999 g/cm³ ± 0.0005 g/cm³ at 20 °C. Trace impurities are below detection limits (<0.02–0.05 mg/L), ensuring high purity. Homogeneity and stability studies confirm reliability over a five‐year shelf life when stored at 5–30 °C and used within 12 months after first opening.

Benefits and Practical Applications

This CRM enables:

• Accurate calibration of ion chromatography, atomic spectrometry (AAS, AES, ICP-OES, ICP-MS), molecular absorption, and selected electroanalytical methods.
• Validation of analytical methods and quality assurance in laboratories.
• Traceability to SI units and compliance with international standards.

Future Trends and Potential Uses

Future developments may include:

• Expansion of CRM offerings to cover broader concentration ranges and matrices.
• Digital certificates and blockchain-based traceability systems.
• Custom blended standards and multi-analyte solutions for high-throughput analytics.
• Further reduction of uncertainties through advanced characterization techniques.

Conclusion

ASTASOL AN8072HIC is a rigorously characterized aqueous chloride standard, delivering high confidence in analytical results and compliance with ISO guidelines. Its certified value, traceability, and stability profile make it indispensable for laboratories requiring precise chloride determination.

Used Instrumentation

• Precision gravimetric balance for primary preparation.
• Ultrafiltration membrane (0.45 µm).
• Argentometric titration apparatus.
• Ion chromatograph for impurity analysis.