Spectrophotometric Determination of Furosemide Using Pyrogallol Reagent in Pharmaceutical Preparations

This research presents a rapid and accurate spectrophotometric method for furosemide determination. This method depended on charge transfer reaction of furosemide with pyrogallol reagent using sodium carbonate. It was observed that a product with a bluish-green color was formed after completing the addition and gave the highest absorption intensity at the wavelength of 610 nm. Following Beer s law, the straight standard curve was obtained in the concentration range of (1-20 μg/mL. The statistical results showed that the method has good accuracy and agreement. The molar absorptivity value was 2.3813×10^4 l/mol.cm and sensitivity of Sandell s was 0.0138 μg/cm^2. The relative standard deviation (RSD%) values ranged from 0.18 to 0.71%, relying on the concentration level. For the furosemide estimation, the suggested method has been successfully applied in its pharmaceutical preparations and pure form.