Our phyproof® Reference Substances are mostly certified as primary reference substances as defined by the European Pharmacopoeia, United States Pharmacopoeia, and other international institutions. Their identity is confirmed by a combination of advanced analytical techniques such as NMR, MS and IR. In addition, our reference substances feature a defined absolute content value that is based on a mass balance approach considering chromatographic purity as well as content of water, residual-solvents and inorganic impurities. Counter-ions are also taken into account where appropriate.
