Plant and Soil

, Volume 55, Issue 3, pp 353–361 | Cite as

Evaluation of extractants for soil humic substances

I. Isotachophoretic studies
  • Gustavo A. Orioli
  • Néstor R. Curvetto


An evaluation of alkaline extractants was done by isotachophoresis and compared with infrared, ultraviolet and visible spectroscopic analysis. The electrophoretograms show that the humic acid extracted. This result is partially corroborated by the E4/E6 ratio. Differences in the carboxyl content and TRIS. In the pyrophosphate humic acid three fractions of high molecular weight were not extracted. This resultis partially corroborated by the E4/E6 ratio. Differences in the carboxyl content found by ir spectra of the TRIS humic acid and the NaOH humic acid were not shown in the isotachophoretic separation.

Key Words

Electrophoresis Extractants Isotachophoresis Humic acid 


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Copyright information

© Martinus Nijhoff Publishers 1980

Authors and Affiliations

  • Gustavo A. Orioli
    • 1
  • Néstor R. Curvetto
    • 1
  1. 1.Departmento de Ciencias AgrariasUniversidad Nacional del SurBahía BlancaArgentina

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