Determination of sulphamethoxazole by photochemically induced fluorescence in drugs and milk

A new first-derivative photochemically induced fluorescence (D-PF) method is proposed for the determination of sulphamethoxazole (SMXZ) in milk. A 50:50 (v/v) methanol: water medium, UV irradiation time of 2 min, and pH 5.70 were fixed. Standard addition method was used with the derivative spectra of the increase spectra as analytical signal. For determination in drugs, direct increase of fluorescence signal measure is used. In both cases the method is suitable for SMXZ concentrations comprised between 0.5 and 2.5 ppm.