Asymmetrical Flow Field Flow Fractionation–Multidetection System as a Tool for Studying Metal–Alginate Interactions

Enrica Alasonati; Björn Stolpe; Maria-Anna Benincasa; Martin Hassellöv; Vera I. Slaveykova

doi:10.1071/EN06024

RESEARCH FRONT

Previous Next Contents Vol 3(3)

Asymmetrical Flow Field Flow Fractionation–Multidetection System as a Tool for Studying Metal–Alginate Interactions

Enrica Alasonati ^A , Björn Stolpe ^B , Maria-Anna Benincasa ^A ^C , Martin Hassellöv ^B and Vera I. Slaveykova ^A ^D

+ Author Affiliations

- Author Affiliations

^A Environmental Biophysical Chemistry, Environmental Science and Technology Institute, School of Architecture and Civil Engineering, Ecole Polytechnique Fédérale de Lausanne, Lausanne, CH-1015, Switzerland.

^B Department of Chemistry, Analytical and Marine Chemistry, Göteborg University, SE-412 96 Göteborg, Sweden.

^C Department of Chemistry, University ‘La Sapienza’, Rome 00185, Italy.

^D Corresponding author. Email: vera.slaveykova@epfl.ch

Environmental Chemistry 3(3) 192-198 https://doi.org/10.1071/EN06024
Submitted: 4 April 2006 Accepted: 19 June 2006 Published: 10 July 2006

Environmental Context. Acidic polysaccharides are important components of the organic matter in ecosystems that are involved in the transport of metal pollutants. They are able to affect trace element cycling, both due to their metal binding properties and to their effect on aggregation and sedimentation of organic matter. In order to obtain more information regarding their role as metal pollutant carriers, the size distributions of alginate and metal alginate complexes have therefore been studied with novel instrumentation.

Abstract. The present study explores the potential use of asymmetrical flow field flow fractionation (aFlFFF) with a multidetection system for the study of metal–alginate interactions. aFlFFF, coupled on-line to a differential refractive index and seven angle laser light scattering detectors was used to provide information on the alginate size distributions. In parallel, the metal distributions of metal–alginate complexes were probed by aFlFFF–high resolution inductively coupled plasma-mass spectrometry. Average values and continuous distributions of molar masses, radiuses of gyration and hydrodynamic radiuses, which are critical for understanding the role of alginates as carriers of metal pollutants, were evaluated in presence of Pb or Cd and compared with those in metal-free solutions of alginate. The values of number average and weight average molar mass, weight average radius of gyration and shape factor for alginate were 150 and 188 kg mol^–1, 53 nm and 1.7, respectively. Alginate molar mass and radius of gyration distributions were slightly shifted to higher values by the addition of micromolar concentrations of Pb or Cd. The alginate size distribution in the presence of Cd was similar to the alginate-alone control, whereas in the presence of Pb the size distribution was broader with a shift of the maximum toward higher molar masses.

Keywords. : acidic polysaccharides — biological monitoring — bound residues — FlFFF [flow field flow fractionation] — size and molar mass distributions

Acknowledgements

VS and EA thank the Swiss National Science Foundation (PP002–102640) for providing funding directly related to this work. BS and MH acknowledge the financial support of FORMAS and KA Wallenberg foundation. The comments and suggestions of the editor and four anonymous reviewers are also highly appreciated.

References

Asymmetrical Flow Field Flow Fractionation–Multidetection System as a Tool for Studying Metal–Alginate Interactions

Acknowledgements

Subscriber Login