Spectrophotometric Determination of Furosemide Drug in Different Formulations using Schiff’s Bases

Furosemide (Fu) chemical name is 5-(aminosulfonyl)-4chloro-2-[(2-furanyl methyl)amino)benzoic acid] (Figure 1) [1]. It has the following generic names: Frusemide, Fursemide, Aisemide, Beronald, Desdimin, Lasilix and others. The empirical formula is C12H11ClN2O5S corresponds to molecular weight of 330.77. Furosemide is a white to slightly yellow, odourless, almost tasteless crystalline powder, slightly soluble in water, chloroform and ether [2] soluble in acetone, methanol, dimethyl formamide [1] and in solutions of alkali hydroxides [2]. Its melting point is 206°C, the pH of the aqueous solution is in the range 8.9 to 9.3. The UV spectrum of furosemide (0.01 mg/ml) in 0.1N NaOH was scanned from 190 to 400 nm using DMS 90 Varian spectrophotometer. It exhibited two maxima at 226 and 272 nm. The infrared absorption spectrum for furosemide is shown in Figure 2. Several methods have been reported for the determination of the components of this important drug (furosemide). Titrimetric methods [3-7], Potentiometric methods [8,9] Ultraviolet methods [10-16], Colorimetric methods [17-35].