Spectrophotometric Determination of Sulfamethoxazole with P-N,N-dimethyl amino benzaldehyde as Condensation Reaction

Sulfamethoxazole (SMX) was added to P-N,N-dimethyl amino benzaldehyde (PDAB) by condensation reaction in acidic medium to form, a yellow colored dye compound which exhibits maximum absorption (λmax) at 450.5 nm. The concentration of (SMX) was determined spectrophotometrically. The optimum reaction conditions and other analytical parameters were evaluated. In addition to classical univariate optimization, design of experiment method has been applied in optimization of the variables affecting the color producing reaction. Beer’s law obeyed in the concentration range of 0.1-10 μg.mL-1 with molar absorptivity of 5.7950×104 L.mol-1.cm-1. The limit of detection and Sandell's sensitivity value were 0.078 μg.mL-1 was 4.3706 μg.cm-2 respectivily. The proposed method could be successfully applied to the determination of (SMX) in synthetic sample and urine.