Development of Spectrophotometric methods for Assay of Salbutamol in Pharmaceutical Formulations

Theia’a N Al-Sabha

doi:10.33899/edusj.2007.51279

Abstract

Two sensitive spectrophotometric methods are proposed for the determination of salbutamol in pure form and pharmaceutical preparations. The methods are based on the oxidation of salbutamol drug with Fe(III) in acidic medium. The liberated Fe(II) reacts with 1,10-phenanthroline in method A and the ferroin complex is colorimetrically measured at 510 nm against reagent blank. Method B is based on the reaction of the liberated Fe(II) with 2,2'-bipyridyl to form a stable coloured complex with maximum absorption at 520 nm against reagent blank. Beer's law was obeyed in the concentration range of 0.15-6.00 µg/ml and 0.25-8.00µg/ml with molar absorptivity of 7.858×104 and 4.555×104 l.mol-1.cm-1 for method A and B respectively. The mean percent recoveries are 100.39% and 99.11% for both methods respectively. The suggested procedures could be used for the determination of salbutamol in pure and dosage forms without interference from common excipients. The proposed methods are successfully compared with the official and other spectrophotometric methods.

Highlights

Salbutamol{(RS)-2-(1,1-dimethyl)ethylamino-1-[4-hydroxy-3-(hydroxymethyl)-phenyl]ethanol}(I) is a direct-acting sympathomimethic with beta-adrenergic activity, employed as bronchodilator for the treatment of asthma and chronic obstructive pulmonary disease
The pure drug is analyzed by nonaqueous titration with perchloric acid while the analysis of tablets is carried out by liquid chromatography
Spectrophotometry is the technique of choice even today due to its inherent simplicity

Summary

Introduction

(hydroxymethyl)-phenyl]ethanol}(I) is a direct-acting sympathomimethic with beta-adrenergic activity, employed as bronchodilator for the treatment of asthma and chronic obstructive pulmonary disease. 2,2'-Bipyridyl solution(0.05M) was prepared by mixing 0.2809g of 2,2'-bypyridyl with minimum volume of ethanol and diluted to the mark in a 100m1-volumetric flask with distilled water. General procedure Aliquots of standard drug solution of salbutamol were transferred into a series of 10 ml calibrated flasks. To each of these were added 0.5 ml of Fe(NO3)3.9H2O solution and 2 ml of 1,10-phenanthroline solution in method A and 0.3 ml of Fe(NO3)3.9H2O and 1.5 ml of 2,2'-bipyridyl solution in method B. 2mg of salbutamol was transferred into a 50 ml calibrated flask and diluted to the mark with distilled water. An a liquid of drug solution was analysed as described in general procedure

Results and discussion

Method A

Conclusion