title: Spectrophotometric determination of [2-(2,6-dichloro-phenylamino)-phenyl]-acetic acid in pure form and in pharmaceuticals.
abstract: A new sensitive and selective spectrophotometric method has been developed for the determination of [2-(2,6-dichloro-phenylamino)-phenyl]-acetic acid in pharmaceuticals in the presence of nicotinic acid. The method is based on the reaction of [2-(2,6-dichloro-phenylamino)-phenyl]-acetic acid with 1,3,3-trimethyl-5-phenyl-2-[3-(1,3,3-trimethyl-1,3-dihydro-indol-2-ylidene)-propenyl]-3H-indolium chloride (PIC) followed by the extraction of the formed ion associate into toluene and spectrophotometric detection at 581 nm. Appropriate experimental conditions were found to be pH 7.8-9.8 and 3.6x10(-4) mol L(-1) of PIC. The molar absorptivity is 5.0x10(-4) L mol(-1) cm(-1). The absorbance obeys Beer's law in the range 0.61-12.60 microg mL(-1) of [2-(2,6-dichloro-phenylamino)-phenyl]-acetic acid, and the detection limit calculated from a blank test was 0.20 microg mL(-1).
authors.affiliation: Department of Analytical Chemistry, P.J. Safárik University, Kosice, Slovakia. yaroslav.bazel@upjs.sk
authors.forename: Yaroslav
authors.initials: Y
authors.lastname: Bazel
authors.forename: Iryna
authors.initials: I
authors.lastname: Hunka
authors.forename: Zholt
authors.initials: Z
authors.lastname: Kormosh
authors.forename: Vasil
authors.initials: V
authors.lastname: Andruch
mesh_terms: D000042:Absorption; D000085:Acetates / Q000032:analysis* / Q000737:chemistry; D019342:Acetic Acid / Q000032:analysis*; D000814:Aniline Compounds / Q000032:analysis* / Q000737:chemistry; D004008:Diclofenac / Q000032:analysis; D006863:Hydrogen-Ion Concentration; D007211:Indoles / Q000138:chemical synthesis / Q000737:chemistry; D004364:Pharmaceutical Preparations / Q000737:chemistry*; D012997:Solvents / Q000737:chemistry; D013057:Spectrum Analysis; D014050:Toluene / Q000737:chemistry
chemical_list: C546555:(2-(2,6-dichloro-phenylamino)-phenyl)-acetic acid; D000085:Acetates; D000814:Aniline Compounds; D007211:Indoles; D004364:Pharmaceutical Preparations; D012997:Solvents; D004008:Diclofenac; D014050:Toluene; D019342:Acetic Acid