Determination of some catecholamines in pharmaceutical forms

ABSTRACT

Periodic acid oxidized catecholamines to the corresponding aminochrome derivatives which could be measured spectrophotometrically in acetate buffer [pH 4.7] at 485 nm in the range of 2.4 to 28 mug per ml catecholamines. Catecholamines were also determined amperometrically after their oxidation with periodic acid. In addition, a fluorometric method for the determination of primary amine, e.g. catecholamines, noradrenaline and methyldopa was established. O-phthalaldehyde reacts with these amines in the presence of certain thiol [2-mercaptoethanol] and 50% ammonium acetate to give fluorescent adducts with excitation at 340 nm and emission at 455 nm. Beer's law was obeyed in the concentration range of 1.0 to 12.0 mug per ml catecholamines