title: Spectrophotometric determination of microquantities of Carbidopa, Levodopa and alpha-methyldopa using molybdatophosphoric acid.
abstract: A convenient spectrophotometric procedure for the determination of microquantities of Carbidopa (I), Levodopa (II) and alpha-methyldopa (III) was developed. The method was based on the interaction of acidified molybdatophosphoric acid (MPA) solution with (I), (II) and (III). The resulted deep blue solution was measured spectrophotometrically at lambda = 600-900 nm. The molar absorptivities (epsilon) and the Sandell's sensitivity for (I), (II) and (III) were: 2.4 x 10(4) (I), 3.0 x 10(4) (II), 3.1 x 10(4) (III) and 10.2 ng.cm-2 (I), 6.6 ng.cm-2 (II) and 7.7 ng.cm-2 (III), respectively. The calibration curves were conformed to Lambert-Beer's law between 0.5 and 10.0 micrograms.ml-1.
authors.forename: P B
authors.initials: PB
authors.lastname: Issopoulos
mesh_terms: D002230:Carbidopa / Q000032:analysis*; D007980:Levodopa / Q000032:analysis*; D008750:Methyldopa / Q000032:analysis*; D008982:Molybdenum; D010756:Phosphoric Acids; D013056:Spectrophotometry, Ultraviolet
chemical_list: D010756:Phosphoric Acids; D007980:Levodopa; D008750:Methyldopa; D008982:Molybdenum; D002230:Carbidopa; C003125:phosphomolybdic acid