title: Colorimetric methods for the assay of nomifensine maleate.
abstract: Two colorimetric methods are reported for the assay of nomifensine maleate. The methods are based on coupling between the diazotised form of nomifensine maleate and (i) N-(1-naphthyl)-ethylene diamine dihydrochloride (Bratton-Marshall reagent) and (ii) p-aminosalicylic acid (PAS). The optimum conditions for the reactions were investigated. The coupled products exhibit maximum absorbance at 470 and 435 nm for the Bratton-Marshall and PAS reagents, respectively. With PAS, a linear relationship has been established between absorbance (Amax) and concentration of nomefensine maleate over the range 2-12 micrograms ml-1. Similarly, with the Bratton-Marshall reagent, a linear relationship exists in the concentration range 2-16 micrograms ml-1. The calculated mean percent recoveries for nomifensine maleate in the commercial capsules (Merital 25 mg) respectively. Similarly, for the added recoveries, the percentage obtained were 99.01 +/- 0.46 and 100.03 +/- 1.03, respectively.
authors.affiliation: Department of Pharmaceutical Chemistry, College of Pharmacy, King Saud University, Riyadh, Saudi Arabia.
authors.forename: M A
authors.initials: MA
authors.lastname: Abounassif
authors.forename: M E
authors.initials: ME
authors.lastname: Mohamed
authors.forename: H Y
authors.initials: HY
authors.lastname: Aboul-Enein
mesh_terms: D010131:Aminosalicylic Acid; D003124:Colorimetry; D007202:Indicators and Reagents; D009627:Nomifensine / Q000032:analysis* / Q000737:chemistry; D013056:Spectrophotometry, Ultraviolet
chemical_list: D007202:Indicators and Reagents; D009627:Nomifensine; D010131:Aminosalicylic Acid