The International Union of Pure and Applied Chemistry’s (IUPAC) guidelines for purity assignment of organic compounds have been updated with a newly published Technical Report on best practice. This is the first comprehensive review of the subject since 1970 and has been driven by the profound changes in analytical capability, broader scope of applications and greater focus on the metrology of these materials that have taken place over that period. The guideline was developed by a project team with experts from the CCQM Working Group on Organic Analysis, based on the on-going series of organic purity comparisons coordinated by the BIPM Headquarters’ laboratory, and value assignment procedures for certified reference materials employed by National Metrology Institutes.

Pure organic compounds provide the primary measurement standards that underpin the SI-traceability of measurement results in organic analysis in numerous application areas including quantification of clinical biomarkers, detection and quantification of contaminants in food as well as environmental analysis. The Technical Report has been written as a key reference on this aspect of metrological traceability and as a best practice guide for the delivery of SI-traceability for reference and working methods in organic analysis.

The document is published in the official Journal of IUPAC, Pure and Applied Chemistry.

Further information on purity evaluation guidelines for specific analytes important to food safety and on the application of quantitative NMR techniques for organic purity evaluation can be found at:

https://www.bipm.org/en/committees/cb/cbkt/wg/cbkt-mm-bipm

https://www.bipm.org/en/organic-analysis/qnmr