IMPLEMENTATION OF ULTRAVIOLET SOLID-PHASE SPECTROPHOTOMETRY BY USE OF DERIVATIVE TECHNIQUES

A spectrophotometric method for the simultaneous determination of sulphathiazole and sulphametazine based on fourth-derivative solid-phase spectrophotometry is proposed. Both sulphonamides were fixed on a dextran-type cation-exchange gel at pH 2.5. The absorbance on the gel, packed in a 1-mm silica cell, was measured directly. The method does not require any separation step. The range of application is between 0.20 and 12.00 mug ml 1 for sulphathiazole and between 0.20 and 15.00 mug ml - 1 for sulphametazine. The acuracy and precision of the method are reported. The method was applied for the determination of sulpha thiazole and sulphametazine in synthetic mixtures and pharmaceuticals.