Organic compounds

ISC-Science produces Reference Materials (RM) of isotopically enriched compounds for Isotope Dilution and ICP-MS and/or GC-MS applications.

Isotopic abundance values are reported as percentage [amount fraction (*100), %] and concentration values as micrograms of cation per gram of solution (μg/g). According to ISO 17034 and ISO/IEC 17025, the concentration value was determined by Gas Chromatography with Mass Spectrometry (GC-MS) using a reference method in a single laboratory [Isotope Dilution Mass Spectrometry (IDMS)] and isotopic abundances were determined by measuring the isotope-amount ratios for all isotopes of the element by GC-MS using the enriched isotope as reference. The expanded uncertainty for each value was calculated as U = 2 · u, where k = 2 is the coverage factor for a 95% confidence interval and u is the combined standard uncertainty calculated according to ISO Guide 35. The value of u is intended to represent the combined effect of uncertainty components associated with IDMS determination, homogeneity and stability for concentration values and the GC-MS determination for abundance values.

Stability of this material is based upon rigorous long-term (storage conditions) and short-term (transport conditions) testing of the solution for the values according to ISO 17034 and ISO Guide 35. This testing includes, but is not limited to, the effect of temperature.