Spectrophotometric determination of salbutamol Sulphate by coupling with diazotized 5-amino-2-chlorobenzotrifluoride : application to pharmaceutical preparations

Abstract EN

A simple, rapid and sensitive spectrophotometic method for the estimation of trace amounts of salbutamol sulphate (SBS) in pharmaceutical preparations has been proposed .The method is based on the coupling reaction of the intended compound with diazotized 5-amino-2- chlorobenzotrifluoride in alkaline medium and in the presence of Triton X-100 to form a yelloworange dye that shows maximum absorption at 467 nm.

Beer’s law is obeyed over the range 5 – 300 μg / 10 ml (i.e.,0.5-30 ppm) with a molar absorptivity of 4.20 × 104 l.mol-1.cm-1 and Sandell’s sensitivity index of 0.0139 μg.cm-2, a relative error of +1.08 to +3.46 % and a relative standard deviation of ±0.76 to ±3.50 %, depending on the concentration.

The method has been applied to estimate salbutamol sulphate in syrup, tablet and ventolin.