S.T.P. Pharma Sciences, vol.1, no.4, pp.276-279, 1991 (Scopus)
In this paper, rapid first derivative ultraviolet spectrophotometric assay procedures are described for the simultaneous determination of phenazopyridine hydrochloride, ampicillin trihydrate, nitrofurantoin and sulfisoxazole in the binary mixtures of phenozopyridine hydrochloride/ampicillin trihydrate, phenazopyridine hydrochloride/nitrofurantoin and phenazopyridine hydrochloride/sulfisoxazole. The methods were successfully applied to the tablets and capsules containing these binary combinations. The specificity, accuracy and precision of the methods have been assessed.