Titrimetric Assay of Salbutamol Sulfate Using Permanganate

Abstract

Introduction: Salbutamol, RS-[4-[2-(tert-butylamino)-1-hydroxyethyl]-2(hydroxymethyl) phen-ol] is a short acting β2-adrenergic receptor agonist used for the relief of Broncho-spasm in conditions such as asthma and chronic obstructive pulmonary disease [1-3]. Salbutamol is still commonly delivered as a racemic mixture (+,-). Salbutamol, even though S-Salbutamol is known to have a detrimental effect on asthma sufferers (in fact the exact opposite effect of the R Isomer) [4].

Objectives:A simple cost-effective, accurate and precise direct titrimetric method for the determination of Salbutamol sulfate (SBS) in pharmaceutical dosage forms has been developed and validated.

Methods:The method is based on the titration of SBS with acidified 0.01M potassium permanganate solution. The method is applicable over the range of 3.0-10.0mg SBS.

Results:The validation of the method yielded good results that included precision (RSD < 3.15% for intra- and inter-day precision, accuracy (relative error < 3.12%).It was also found that the additives present in the commercial tablets did not interfere with the assay and the results were comparable with the existing method.

Conclusions:The proposed method is free from rigid experimental conditions such as rigid pH control, liquid-liquid extraction, etc., and is characterized by simplicity and high sensitivity. This method employ inexpensive and easily available chemicals and hence cost-effective when compared to the existing methods. In addition, the method has a high tolerance limit for common excipients found in drug formulations. The proposed method is accurate and precise as indicated by good recoveries of the drugs and low RSD values. The proposed method can be applied for routine analysis and in quality control laboratories for quantitative determination of the drug both in the pure and dosage forms.