Flow-injection chemiluminometric determination of some phenothiazines in dosage forms and biological fluids

A rapid and sensitive how-injection chemiluminometric method is described for the determination of three phenothiazine derivatives, namely, fluphenazine hydrochloride, levomepromazine hydrochloride and trimeprazine tartrate. The method is based on the chemiluminescence (CL) induced by the oxidation of drugs with cerium(IV) in an acidic medium. The CL intensity is greatly enhanced when rhodamine B is used as a sensitizer in the case of levomepromazine hydrochloride and trimeprazine tartrate. The proposed method allows the measurement of 0.5-90 mu g ml(-1) fluphenazine and 0.1-6.5 mu g ml(-1) levomepromazine and trimeprazine. The limits of detection (3 sigma) were 0.01 mu g ml(-1) fluphenazine hydrochloride and 0.1 mu g ml(-1) for the other two drugs. The method was applied successfully in determining the drugs in dosage form as well as in biological fluids. (C) 1998 Elsevier Science B.V.