Determinação de anião nitrato em águas por FIA usando um detector potenciométrico tubular

José L.F.C. Lima*, António O.S.S. Rangel, M. Renata S. Souto

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

4 Citations (Scopus)


In this work, a flow injection system for the potentiometric determination of nitrate content in waters, is described. A tubular nitrate ion-selective electrode without inner reference solution and an ion-exchanger system composed of (4,7-diphenylphenanthroline)nickel (II) nitrate in o-nitrophenyl octyl ether was used as indicator electrode. These units were evaluated In two ionic strength adjustor solutions and their operational characteristics compared with those of conventionally shaped electrodes with the same sensor system. The developped methodology allows the determination of nitrate anion in waters without sample pre-treatment and with a high sampling rate (ranging from 60 to 120 determinations per hour) and precision (relative standard deviations inferior to 2%). Results are in good agreement with the reference procedure and the lower limit of linear response is 14.9 mg L-1.

Original languagePortuguese
Pages (from-to)82-88
Number of pages7
JournalRevista Portuguesa de Farmácia
Issue number2
Publication statusPublished - 1 Dec 1996


  • Flow injection analysis
  • Nitrate
  • Waters
  • Ion-selective electrode

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