CERIUM(IV)-BASED CHEMILUMINESCENCE ANALYSIS OF HYDROCHLOROTHIAZIDE

A flow-injection analytical method for the determination of hydrochlor othiazide is presented. The method is based on the chemiluminescence r eaction of hydrochlorothiazide with cerium(IV) in sulphuric acid, sens itized by the fluorescent dye rhodamine 6G. The proposed procedure all ows quantitation of hydrochlorothiazide in the concentration range of 0.33-130 mu mol 1(-1) with a detection limit of 0.15 mu mol 1(-1), an RSD of 2.4% at 10 mu mol 1(-1) and a sample measurement frequency of 2 00 h(-1). The method was successfully applied to the determination of hydrochlorothiazide in pharmaceutical preparations containing, amongst others, lactose, maize starch, calcium phosphate, magnesium stearate, potassium chloride and E 110 (disodium-6-hydroxy-5-(4-sulphonatopheny lazo) naphthalene-2-sulphonate) as the concomitant species. Apart from the single formulation, hydrochlorothiazide was also determined in ta blets combined with the antihypertensive lisinopril. (C) 1998 Elsevier Science B.V. All rights reserved.