Spectrophotometric quantification of fenoterol hydrobromide in tablets and inhalation aerosol.

Abstract

The cited drug (I) was determined in dosage forms by (i) difference and (ii) first-derivative spectrometry. In method (i), a 1-ml portion of sample soln. (prep. described) was diluted to 10 ml with 0.1M-HCl and a similar portion was diluted to 10 ml with 0.1M-NaOH. The absorbance of each was measured at 295 nm vs. the appropriate reagent blank. In method (ii), the first derivative spectra were recorded from 200 to 350 nm and the value at 281 nm was measured. Calibration graphs were rectilinear from 20 to 70 and 10 to 60 µg ml–1 of I for methods (i) and (ii), respectively. The methods compared well with each other and recoveries were quantitative.