CRM Bromides (Br-) - Aqueous calibration solution ASTASOL® AN90711H

Importance of the topic

Certified reference materials (CRMs) are fundamental for ensuring the accuracy, precision and traceability of quantitative analyses in aqueous matrices. A well-characterized bromide calibration solution underpins reliable results across atomic and molecular spectrometry as well as electroanalytical methods, supporting quality assurance and regulatory compliance in environmental, pharmaceutical and industrial laboratories.

Objectives and overview of the study/article

This document presents the certification of ASTASOL® AN90711H, an aqueous calibration solution of bromide (Br–) at 1 000 mg/L. The primary aims are to describe its preparation, certify its concentration and uncertainty, and provide guidance on proper storage, handling and intended analytical applications.

Used methodology and instrumentation

The solution was prepared gravimetrically from high-purity potassium bromide (KBr 99.999%) dissolved in ultrapure demineralized water. Key steps included:

• Gravimetric weighing under controlled conditions to achieve direct traceability to the SI unit (kilogram).
• Verification of bromide concentration by argentometric titration, establishing expanded uncertainty (k = 2).
• Determination of trace impurities (Cl–, F–, I–, NO₂–, NO₃–, PO₄³–, SO₄²–) by ion chromatography to confirm levels below detection limits.

Main results and discussion

The certified value of bromide is 1 000 mg/L with an expanded uncertainty of ± 2 mg/L (k = 2) at 20 °C, corresponding to 1 001 mg/kg ± 3 mg/kg based on solution density (0.9992 ± 0.0005 g/cm³). Impurity concentrations were found below detection thresholds (< 0.02 mg/L for most species, < 0.05 mg/L for sulfate). Homogeneity tests confirmed uniform distribution across the batch and stability assessments guarantee integrity over the five-year shelf life when stored at 5–30 °C.

Benefits and practical applications

ASTASOL® AN90711H provides a traceable, high-purity standard for calibrating and validating methods in:

• Atomic spectrometry (AAS, AES, ICP-OES, ICP-MS)
• Molecular absorption spectrometry
• Selected electroanalytical techniques

Its clear handling instructions and long shelf life facilitate routine laboratory workflows and support compliance with ISO/IEC 17025 requirements.

Future trends and possibilities

Emerging developments in CRM production may include multiparameter aqueous standards, automated gravimetric dispensing systems and digital certification with blockchain-enabled traceability. Integration of real-time stability monitoring and on-demand dilution protocols could further streamline calibration processes.

Conclusion

ASTASOL® AN90711H meets stringent ISO Guide 31 and ISO 17034 criteria, offering a robust, SI-traceable bromide standard with low uncertainty and demonstrated homogeneity. It addresses critical calibration needs across diverse analytical platforms, enhancing data quality and laboratory confidence.

Reference

International Organization for Standardization. Guide 31: Reference Materials—Contents of Certificates and Labels. ISO, 2000.
ANALYTIKA® Department of Reference Materials. Detailed Information about the Production of Aqueous Calibration Solutions ASTASOL®. Prague, 2023.