Spectrophotometric Estimation Of Ambroxol Hydrochloride In Tablets
Two spectrophotometric methods in visible region have been developed for estimation of ambroxol hydrochloride in bulk drug and in tablets. In method A1 the -NH2 group of ambroxol reacts with sodium nitrite and forms a diazo compound which couples with N- (1-naphthy1)- ethylene diamine dihydrochloride to form a pinkish red chromogen which exhibits maximum absorption at 500 nm against a reagent blank. Method B is based on the reduction of ferric ions in its salt to ferrous ions by the drug, producing a yellowish orange chromogen with absorption maximum at 400 nm against the reagent blank. Beer's law was obeyed in the range of 10 to 50 Î¼g/ml for method A and 40 to 240 Î¼g/ml for method B. The results of analysis have been validated statistically and by recovery studies. The recovery ranged between 100.6 and 100.3% for method A and between 99.6 and 100.2% for method B. This paper describes new, simple and sensitive colourimetric methods for the estimation of ambroxol hydrochloride in bulk drug and pharmaceutical dosage forms.