scope:

This European standard describes the determination of NOGE components with more than two aromatic rings (the two-ring NOGE is equal to BFDGE = Bis(2-hydroxyphenyl)methane bis(2,3-epoxypropyl)ether) and at least one epoxy group as well as their derivatives containing chlorohydrin functions and having a molecular mass less than 1000 Daltons in can coatings. A high performance liquid chromatography (HPLC) method is employed based on reversed phase HPLC and fluorescence detection. The method is capable of determining NOGE and its derivatives at a minimum level of 1 g/ml in solution. Direct HPLC analysis of the can coating extract may result in chromatograms difficult to interpret, due to interference from other components or the instability of the monomer resulting in a complex mixture of derivatives and/or reaction products. By forced hydrolysis of all epoxy groups and their reaction products, the quantification of the NOGE is simplified and the identities of the substances are indicatively confirmed.