AUTHOR=Bartacek Jan , Vergeldt Frank J. , Maca Josef , Gerkema Edo , Van As Henk , Lens Piet N. L. TITLE=Iron, Cobalt, and Gadolinium Transport in Methanogenic Granules Measured by 3D Magnetic Resonance Imaging JOURNAL=Frontiers in Environmental Science VOLUME=4 YEAR=2016 URL=https://www.frontiersin.org/journals/environmental-science/articles/10.3389/fenvs.2016.00013 DOI=10.3389/fenvs.2016.00013 ISSN=2296-665X ABSTRACT=
Description of processes such as bioaccumulation, bioavailability and biosorption of heavy metals in biofilm matrixes requires the quantification of their transport. This study shows 3D MRI measurements of the penetration of free (Fe2+, Co2+ and Gd3+) and complexed ([FeEDTA]2− and [GdDTPA]2−) metal ions in a single methanogenic granule. Interactions (sorption or precipitation) between free metals and the biofilm matrix result in extreme shortening of the spin-spin relaxation time (