FLUOROMETRIC-DETERMINATION OF 3,4-DIHYDROYPHENYLALAINE IN PHARMACEUTICAL FORMULATION BY REACTION WITH PARACETAMOL

A new method has been developed for the fluorometric determination of 3,3-dihydroxyphenylalaine (L-dopa) in pharmaceutical formulations. The reaction product, belonging to fluorescent species, has the excitatio n and emission maxima at 410 and 510 nm, respectively. Under the optim um conditions, responses were linear between 0.06-4.0 and 4.0-12.0 mu g ml(-1). The detection limit, corresponding to a signal-to-noise rati o of 3, was 1 ng ml(-1). The relative standard deviation (n = 10) was 0.6%. The proposed method was applied to determination of L-dopa in ph armaceutical formulations. (C) 1998 Elsevier Science B.V. All rights r eserved.