Determination of Salbutamol Sulfate and Its Impurities in Pharmaceuticals by Supercritical Fluid Chromatography

Salbutamol sulfate, shown above, is a bronchodilator used for the treatment of asthma. Most of the papers published in relation to salbutamol sulfate analysis described its determination and quantification in tissues and biological fluids of animals under treatment with this drug. Normally, the methods employed are based on high-performance liquid chromatography (HPLC) techniques using detectors of high sensitivity such as fluorescence (1 –3 ) and electrochemical (4 –6 ). It is known that there are some impurities that could be produced during synthesis or during storage of the drug. Consequently, there is great interest in the analysis of the drug and its impurities. HPLC (7 ) or capillary electrophoresis (8 ) methods have been used to determine these compounds, but only two of the impurities were analyzed. Recently, salbutamol sulfate and six related impurities were separated by HPLC in 30 min (9 ). To shorten this time, analysis of the same samples by supercritical fluid chromatography (SFC) was tried. It was found that analysis times of less than 15 min were possible (10 ).