title: [Improved spectrophotometric determination of total iron and iron(III) with o-hydroxyhydroquinonephthalein and their characterization].
abstract: Simultaneous and fractional determination of iron(II) and iron(III) was accomplished with o-hydroxyhydroquinonephthalein (QP) in the presence of poly (N-vinyl pyrrolidone). In the determination of total iron (iron(II)+iron(III)), Beer's law was obeyed in the range of 0.02-0.67 μg·ml(-1), with an effective molar absorptivity (at 570 nm) and a relative standard deviation of 1.30×10(5)·l·mol(-1)·cm(-1) and 0.77% (n = 8), respectively. This method was about 10-15 times and more than the methods using 1,10-phenanthroline and 2,2'-bipyridine. In addition, the iron-QP complex was characterized using spectrophotometry and the electron spin resonance. This method was successfully applied to assays of total iron and iron(III) in pharmaceutical preparations.
authors: Osaka University of Pharmaceutical Sciences, Osaka, Japan.
authors: Mitsuru
authors: M
authors: Hoshino
authors: Hiroyuki
authors: H
authors: Yasui
authors: Hiromu
authors: H
authors: Sakurai
authors: Takako
authors: T
authors: Yamaguchi
authors: Yoshikazu
authors: Y
authors: Fujita
mesh_terms: D002021:Buffers; D005290:Ferric Compounds / Q000032:analysis*; D006863:Hydrogen-Ion Concentration; D006873:Hydroquinones; D007501:Iron / Q000032:analysis*; D004364:Pharmaceutical Preparations / Q000737:chemistry; D012680:Sensitivity and Specificity; D012996:Solutions; D013053:Spectrophotometry / Q000379:methods*; D013501:Surface-Active Agents
chemical_list: D002021:Buffers; D005290:Ferric Compounds; D006873:Hydroquinones; D004364:Pharmaceutical Preparations; D012996:Solutions; D013501:Surface-Active Agents; C039209:2-hydroxyhydroquinonephthalein; D007501:Iron