Element-to-tissue correlation in biological samples determined by three-dimensional X-ray imaging methods

Synchrotron radiation based confocal micro-XRF was employed to unravel the tissue-specific three-dimensional (3D) distribution of metals down to trace concentration levels in a non-destructive manner within the crustacean Daphnia magna, an ecotoxicological model organism. Next to the analytical characterization of the employed confocal micro-XRF set-up, specific areas of metal accumulation in different cross-sections of interest within the organism were investigated. The use of a fast dynamic (continuous) scanning approach delivered 3D information on major, minor and trace element distributions in specific sub-regions within Daphnia magna. Coupling the obtained elemental information with microscopic morphological data obtained by laboratory absorption microtomography, full 3D element-to-tissue correlation could be derived, allowing a more detailed interpretation of the obtained results with respect to metal accumulation within this model organism.