Catecholamines in urine; an evaluation of alumina-trihydroxyindole methods and a description of an improved method

A critical assessment of the accuracy and practicability of five alumina-trihydroxyindole methods for the estimation of urinary catecholamines, including our proposed method, was undertaken. The recovery of noradrenaline added to urine obtained by these methods was quantitated against different types of standards, and varied from 22.9 per cent to 104.8 per cent. The major analytical problems (fluorescence suppression and loss of catecholamines during column chromatography) were evaluated and related to the recovery of the respective procedures. The improved method we developed is simple, rapid and reliable. The low fluorescence suppression and column losses of noradrenaline of this method, averaging 2.9 per cent and 5.3 per cent, respectively, resulted in a mean recovery of 92.0 per cent against an external standard. Both the chromatography step and fluorescence development are simple and short, and a batch of ten cases can be completed within 3 hours.