Pharmacy World and Science

, Volume 15, Issue 5, pp 208–211 | Cite as

Polarographic determination of metyrosine through treatment with nitrous acid

  • F. A. Aly
  • F. Belal
  • A. El-Brashy


A simple and sensitive polarographic method is described for the determination of metyrosine through treatment with nitrous acid. The different experimental parameters affecting the derivatization process, as well as the polarographic analysis were studied. The derivatization product was found to be reducible at the dropping mercury electrode over the whole pH range in Britton Robinson buffers. At pH 5, a well-defined diffusion-controlled cathodic wave was produced. The limiting current versus the concentration plot was linear over the range 8–80μmol/l in the direct current mode with a detection limit of 0.2μmol/l. The method was then applied to the determination of metyrosine capsules, and the results obtained were in good agreement with those given by the USP method.


Chemistry, analytical Metyrosine Polarography 


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Copyright information

© Periodicals Service Company 1993

Authors and Affiliations

  • F. A. Aly
    • 1
  • F. Belal
    • 1
  • A. El-Brashy
    • 1
  1. 1.Department of Analytical Chemistry, Faculty of PharmacyUniversity of MansouraMansouraEgypt

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