Standard substance: pure amprolium, 1-[(4-amino-2-propylpyrimidin-5-yl)methyl]-2-methyl-pyridinium chloride hydrochloride, E 750 (see 9.2).
Substance étalon: amprolium pur, chlorhydrate chlorure de 1-[(4-amino-2-propylpirimidin-5-yl)méthyl]-2-méthyl-pyridinium, E 750 (voir 9.2).