Abstract

Spectrophotometric Study of the Interaction Between Hexacyanoferrate (II) Ion and Sulphamethoxazole Catalyzed by Mercury (II) Ion

Author(s): T. Ramachar, K. M. Rafi, M. Umamahesh and Nuzhath Fathima

Potassium hexacyanoferrate when mixed with sulphamethoxazole at pH 4 in 20% dimethyl formamide (DMF) in the presence of mercury (II) forms an intense reddish brown coloured species. The maximum colour development occurs at 30 mins after mixing. The colour formation is spectrophotometrically monitored under the established optimum experimental conditions. The optimum conditions established are: pH 4, 20% DMF solvent, 520 nm as wavelength of maximum absorbance, 3-4 fold excess of hexacyanoferrate (II) to sulphamethoxazole, 1 x 10-5 M concentration of mercury (II). The colour reaction is successfully investigated for the spectrophotometric determination of sulphamethoxazole in the range 0.5 mg/mL-1.6 mg/mL. The proposed method is suitably applied for the estimation of the drug in Septron tablets.