IMPLEMENTATION OF ULTRAVIOLET SOLID-PHASE SPECTROPHOTOMETRY BY USE OFDERIVATIVE TECHNIQUES

A spectrophotometric method for the simultaneous determination of sulp hathiazole and sulphametazine based on fourth-derivative solid-phase s pectrophotometry is proposed. Both sulphonamides were fixed on a dextr an-type cation-exchange gel at pH 2.5. The absorbance on the gel, pack ed in a 1-mm silica cell, was measured directly. The method does not r equire any separation step. The range of application is between 0.20 a nd 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 r eported. The method was applied for the determination of sulpha thiazo le and sulphametazine in synthetic mixtures and pharmaceuticals.