First Material Certified for Carbon Isotope Ratios Traceable to the SI Produced

LGC has produced the first material certified for carbon isotope ratios traceable to the SI (International System of Units).

The amino acid (Glycine) reference material is certified for absolute carbon isotope ratios and will benefit food and drug testing laboratories, forensic analysts and research laboratories in the field of biogeochemistry.

The LGC team successfully developed a novel calibration strategy based on the use of gravimetrically prepared synthetic isotope mixtures from enriched carbon isotopes for the determination of absolute carbon isotope ratios by multicollector-inductively coupled plasma- mass spectrometry (MC-ICPMS).  Two technical papers describing the calibration procedure have been published in the Journal of Analytical Atomic Spectrometry and Analytical and Bioanalytical Chemistry. This validated method was used to produce an amino acid (Glycine) reference material certified for absolute carbon isotope ratios, which are traceable to the SI.

SI traceable absolute carbon isotope ratios and the certification of reference standards underpin important industrial sectors, including pharmaceutical, fuel, food and feed, as well as aiding analytical, geochemical and forensic laboratories.

Glycine with certified 13C/12C isotope amount ratio traceable to the SI has now been approved by the European Reference Materials (ERM®) consortium and is the first reference material produced with SI traceable absolute carbon isotope ratios. The material, ERM®-AE672a, is available from LGC’s Standards division. LGC’s scope of accreditation for the production of reference materials to ISO Guide 34, has recently been extended to include the production of glycine characterised for the 12C /13C isotope ratio. This is reinforced by recent ISO/IEC 17025 accreditation for the measurement step.

The validation of methodologies for absolute carbon isotope ratio measurements builds on a growing key platform capability established within LGC through its role as a designated National Measurement Institute for chemical and bio-measurement. It establishes the basis for assigning values that meet the needs of UK industry and law enforcement bodies. The assignment of traceable carbon isotopic ratios to materials of interest allows assessment of measurement accuracy and helps the interested parties gain traceability to the SI for these measurands.