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.