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Immobilized humic substances and immobilized aggregates of humic substances as sorbent for solid phase extraction. | LitMetric

Immobilized humic substances and immobilized aggregates of humic substances as sorbent for solid phase extraction.

J Chromatogr A

CESAM & Department of Chemistry, University of Aveiro, Campus de Santiago, 3810-193 Aveiro, Portugal.

Published: September 2013

AI Article Synopsis

  • - The study explores using humic substances immobilized on silica gel for solid phase extraction of triazine pesticides, selected for their environmental significance and varying solubility properties.
  • - A thin layer of humic substances was attached to silica gel using a cationic polymer, and it was found that while more humic substances could be added to form aggregates, there was no significant change in sorption performance.
  • - The new sorbent proved effective in concentrating triazines from various water samples, achieving concentration factors between 50 and 200, while also being cost-effective and efficient in high-flow scenarios.

Article Abstract

In this work, humic substances (HS) immobilized, as a thin layer or as aggregates, on silica gel were tested as material for solid phase extraction. Some triazines (simazine, atrazine, therbutylazine, atrazine-desethyl-desisopropyl-2-hydroxy, ametryn and terbutryn), have been selected as test analytes due to their environmental importance and to span a large range of solubility and octanol/water partition coefficient (logP). The sorbent was obtained immobilizing a thin layer of HS via physisorption on a pre-coated silica gel with a cationic polymer (polybrene). While the sorbent could be used as it is, it was demonstrated that additional HS could be immobilized, via weak interactions, to form stable humic aggregates. However, while a higher quantity of HS could be immobilized, no significant differences were observed in the sorption parameters. This sorbent have been tested for solid phase extraction to concentrate triazines from aqueous matrixes. The sorbent demonstrated performances equivalent to commercial alternatives as a concentration factor between 50 and 200, depending on the type of triazines, was obtained. Moreover the low cost and the high flow rate of sample through the column allowed using high quantity of sorbent. The analytical procedure was tested with different matrixes including tap water, river water and estuarine water.

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Source
http://dx.doi.org/10.1016/j.chroma.2013.07.057DOI Listing

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