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developer of the AIDS-HIV Reference project
Abstract No.: ThP-LB3
Session: LATE-BREAKING/FT-ICR Instrumentation and Methods
Presentation date: Thu, Aug 31, 2006
Presentation time: 09:50 – 11:20

ESI ICR FTMS and NMR analysis of Free-Flow Electrophoresis fractions of Suwannee river NOM

andras gaspar1, Jens Junkers1, Philippe Schmitt-Kopplin1, Norbert Hertkorn1

1 GSF - National Research Center for Environment and Health, Neuherberg, Germany

Correspondence address: andras gaspar, GSF - National Research Center for Environment and Health, Institute for Ecological Chemistry, Ingoldstadter Landstrasse 1, Neuherberg, D-85764 Germany.

Keywords: Electrophoresis, 2D; Ionization, Micro Electrospray (Nanospray); Mass Spectrometry, Ion Cyclotron Resonance; NMR.

Novel aspect: Complementary approach to NOM characterization on the example of Suwannee river NOM sample

 

The level of intricacy in the analysis of large molecules and of mixtures can be classified according to their polydispersity and heterogeneity. The structures of complicated, but monodisperse, natural products and biopolymers are readily accessible (provided that sufficient amounts of materials are available) by a combination of analytical methods, which primarily rely on NMR spectroscopy and mass spectrometry. Supramolecular structures, composed of (modified) biopolymers aligned in aggregates, which are supported and defined by weak interactions, require a more elaborate characterization, which requires an adequate definition of covalently bonded molecules and of their non covalent interactions. Consequently, the characterization and structural analysis of geopolymers, which feature a substantial extent of both polydispersity and molecular heterogeneity, is most demanding with respect to methodology and concepts. Currently, the molecular level structural analysis of NOM/HS is primarily focused on the definition of the covalent bonds. In an ongoing evolution, future high quality structural analyses of NOM/HS will have to provide a characterization of individual molecules and a description of the extent and mechanisms of their interactions.
Complementary organic structural spectroscopy of NOM in conjunction with fractionation creates data sets of high information density. The wealth of inherent multivariate profiling capabilities is of adequate potential and richness to fundamentally advance knowledge and understanding of NOM. The nature of alterations within a range of closely related NOM fractions is a response on a incremental change of “environmental” properties within the separation column (and thus a measure of NOM function under that specific conditions). These conversions can be assessed via in-depth structural analysis and linked to molecular composition and structure. We will demonstrate the significance of the outlined complementary approach to NOM characterization on the example of Suwannee river NOM.
Different capillary electrophoretic techniques could be tested and used with NOM of various origins over the last decade. Free zone electrophoretic techniques allow a separation of NOM on the basis of their own chemical surface properties (charge) and configuration (size) under different solution conditions without interaction with an active phase such as in liquid chromatography.