Metrological traceability for organic chemical measurements is a documented unbroken chain of calibrations with stated uncertainties that ideally link the measurement result for a sample to a primary calibrator in appropriate SI units (e.g., mass fraction). A comprehensive chemical purity determination of the organic calibrator is required to ensure a true assessment of this result. We explore the evolution of chemical purity capabilities across metrology institute members of the Consultative Committee for Amount of Substance: Metrology in Chemistry and Biology’s Organic Analysis Working Group (OAWG). The OAWG work program has promoted the development of robust measurement capabilities, using indirect “mass balance” determinations via rigorous assessment of impurities and direct determination using quantitative nuclear magnetic resonance spectroscopy methods. A combination of mass balance and qNMR has been shown to provide a best practice approach. Awareness of the importance of the traceability of organic calibrators continues to grow across stakeholder groups, particularly in key areas such as clinical chemistry where activities related to the Joint Committee for Traceability in Laboratory Medicine have raised the profile of traceable calibrators.

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CCQM OAWG 在为有机化学测量提供 SI 可追溯校准品方面的作用

有机化学测量的计量溯源性是一个记录在案的不间断校准链，具有规定的不确定性，理想地将样品的测量结果与采用适当 SI 单位（例如，质量分数）的初级校准品联系起来。需要对有机校准品进行全面的化学纯度测定，以确保对该结果的真实评估。我们探索了物质含量咨询委员会计量研究所成员的化学纯度能力的演变：化学和生物学有机分析工作组 (OAWG) 的计量学。OAWG 工作计划促进了稳健测量能力的发展，通过对杂质的严格评估和使用定量核磁共振波谱方法的直接测定，使用间接“质量平衡”测定。质量平衡和 qNMR 的组合已被证明可以提供最佳实践方法。利益相关者群体对有机校准品可追溯性重要性的认识不断提高，尤其是在临床化学等关键领域，与检验医学可追溯性联合委员会相关的活动提高了可追溯校准品的知名度。