SPECTROPHOTOMETRIC DETERMINATION OF AMOXICILLIN INPHARMACEUTICAL PREPARATIONS THROUGH DIAZOTIZATIONAND COUPLING REACTION

Abstract

Two simple, rapid and sensitive spectrophotometric methods have been
developed for the determination of amoxicillin (AMX) in pure form and
pharmaceutical preparations. The proposed methods are based on a coupling
reaction between AMX and diazotized p-amino benzoic acid or diazotized
procain in alkaline medium to form an intense yellow, water-soluble dyes that
are stable and have a maximum absorption at 435 nm using diazotized p- amino
benzoic acid and 450 nm on using diazotized procain. The calibration graphs
were linear over the concentration rangs of 0.4 to 10 5g mL-1 and 0.4 to 14 5g
mL-1 with a limit of detection (LOD) of 0.1877 5g mL-1 and 0.1916 5g mL-
1,molar absorbtivity of 1.914×104 L mol-1cm-1 and 2.544×104 L mol-1cm-1 ,
Sandell<s sensitivity of 21.912×10-3 5g ml-1 and 16.486 ×10-3 5g ml-1 for
diazotized p-amino benzoic acid and diazotized procain, respectively. The
proposed methods were successfully applied to the determination of AMX in
capsules and injections.