ABSTRACT
Three simple and sensitive spectrophotometric methods for the determination of ipratropium bromide (IPB) in liquid for nebulization are described. Method A, is based on the formation of a charge transfer complex with iodine. The reaction product is measured spectrophotometrically at 278 nm. Method B, is based oh the formation of an ion – association complex between the drug and an acidic dye, Bromocresol green (BCG), which is extractable into chloroform and has an absorption maximum at 418 nm. Method C, uses derivative spectrophotometry for the determination of IPB by measuring the D2-value at 232 nm. Beer's law is obeyed over the concentration range 1-10, 2-16 and 5-30 μg ml− for method A, B and C, respectively. The optimum conditions for the formation of the charge transfer or ion-association complexes were optimized. The proposed methods were applied for the determination of IPB in liquid for nebulization. Evaporation to dryness and extraction of the residue with isopropanol, were performed before application of methods A & B. Mean percentage recoveries were found to be 99.67 ± 0.79, 99.26 ± 1.06 and 100.21 ± 0.85 for method A, B, and C, respectively.