Advertisement

Microchimica Acta

, Volume 144, Issue 1–3, pp 81–85 | Cite as

Microwave Single Vessel Acid-Vapor Extraction: Effect of Experimental Parameters on Co and Fe Determination in Biological Samples

  • Geórgia C. L. Araújo
  • Ana Rita A. NogueiraEmail author
  • Joaquim A. Nóbrega
Original Paper

Abstract.

Characteristic parameters of a single vessel procedure were investigated for Co and Fe determination in biological samples using nitric acid-vapor extraction under atmospheric pressure. A laboratory-made PTFE support vessel suitable for four cups containing the samples was adapted to fit on the microwave glass vessel. Biological samples (30 mg) were weighed directly into these PTFE cups and exposed to nitric acid vapor stemming from 15 mL concentrated HNO3 placed in the bottom of the glass vessel. Sample cups were positioned at 50, 80, 110, and 140 mm from the support base. We evaluated the temperature, acidity, and residual carbon content of each sample cup, i.e. parameters that could influence the efficiency of vapor-phase acid digestion. The influence of sample particle size on digestion efficiency was also considered. It was demonstrated that temperature was the main parameter for efficient recovery of both Co and Fe in biological samples, and higher temperatures allowed lower residual carbon contents.

Key words: Sample preparation; microwave; vapor-phase; single-vessel. 

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

Copyright information

© Springer-Verlag/Wien 2003

Authors and Affiliations

  • Geórgia C. L. Araújo
    • 1
    • 2
  • Ana Rita A. Nogueira
    • 1
    Email author
  • Joaquim A. Nóbrega
    • 2
  1. 1.Grupo de Análise Instrumental Aplicada, Embrapa Pecuária Sudeste, Caixa Postal 339, 13560-970, São Carlos, SP, BrazilBR
  2. 2.Departamento de Química, Universidade Federal de São Carlos, São Carlos, SP, BrazilBR

Personalised recommendations