Spectrophotometric Assay of phenylphrine hydrochloride Viacuopling with Diazotised p-Nitroaniline, Application toPharmaceutical Preparation

Abstract

Abstract
Simple, sensitive and reproducible spectrophotometric method was developed in aqueous medium
and applicated forthe.estimation of pheylephrine hydrochloride in nasal drop and tussilet syrup. The
method is based on the formation of orange coloured azo dye fiom the coupling of pheylephrine
hydrochloride (PPH) with diazotised p-nitroaniline in alkaline medium of sodium hydroxide and
sodium carbonate. The intensity of absorbance for the resulting orange azao-dyewas measur ed at 490 nm in sodium hydroxide and at 487 nm in sodium carbonate. Beer's law was obeyed in the
:g]t^t*t:i:n ranges of 10-200pg of PPH (12=0.9988) in sodium hydroxide and of 10-t50pg of ppH
(r:u'9981) tn sodium carbonate in a final volume of l0 ml,.with molar absorptivity of l.t4*l0a
l'mol '.cm-' in sodium hydroxide and 1.98x104 l.mol-l.cm'l in sodium carbonate. The results
demonstrated that the procedure is accurate, precise and reproducible (relative standard deviation was
+0' 8 to +l '53o and relative elror was - 1 .6 to +1 3% depending on the concentration level of (ppH),
while being simple' cheap and less time consuming. The azo-dye was stable for more than 2 hours in
sodium carbonate and for l3 hours in sodium hydroxide.The proposed method was successfully
applied for the dterm.ination of phenylephrine hydrochloride in pharmaceutical nasal drops and
tussilet syrup formulations.