Analysis of Environmental Samples on the Nanometre Scale
Institution
CRP Gabriel Lippmann
Partenaire(s) :
University of Luxembourg
Du : 01/04/2002
Au : 31/12/2008
Budget : 806 578,00€
Contact(s) :
Audinot Jean-Nicolas
,
Hoffmann Lucien
,
Migeon Henri-Noël
Summary
NanoSIMS is a powerful technique for mapping the elemental composition of a variety of small-scale samples (e.g. in Material Research, Cosmochemistry and Geology). However, its analytical features are making it also valuable to address biological questions. In this project we demonstrate the ability of the NanoSIMS 50 to map elements at subcellular lateral resolution (approx. 50 nm) within cyanobacteria (Anabaena sp. and Cylindrospermum alatosporum) and Daphnia magna and its feasibility to investigate the uptake of bromine containing substances (NaBr and deltamethrin).
Elemental maps of O, N, P and S were obtained from semi-thin sections of different cell types (chemically fixed and resin-embedded heterocysts, akinetes and vegetative cells). NanoSIMS enabled the detection of various characteristic cell sub-structures and inclusions. A bromine distribution was detected following NaBr and deltamethrin exposure, at Br- concentrations of 0.5, 0.05 (NaBr) and 0.0025 mmol -1 (deltamethrin).
The results (figure 1) demonstrate the high lateral resolution of the NanoSIMS 50 and the ability of the chemical fixation technique to investigate and map cell structures of different cyanobacterial cell types or daphnia for abundant and physiologically important elements, including oxygen, nitrogen, phosphorus and sulfur. Big structures such as gut or small structures, such as pore channels, cell walls, and thylakoid membranes, could be differentiated. Furthermore, cellular uptake of Br from NaBr and deltamethrin could be monitored. This was the first report applying the NanoSIMS 50 for xenobiotic exposure studies in living organisms. NanoSIMS allowed the study of the mapping of common elements in daphnia and cyanobacterial cells and the uptake of NaBr and deltamethrin. These results highlight the potential usefulness of NanoSIMS analysis for tracking elements within cell structures at the nanoscale and the ability to detect marker elements of xenobiotic compounds within exposed organisms.
The lateral resolution of the Cameca NanoSIMS 50 is 300nm for positive secondary ions. In order to obtain a better lateral resolution for these ions a Liquid Metal Ion Gun (LMIG) filled with gallium (Ga+) has been installed on the Cameca IMS-6F. The advantage of the Gallium bombardment for the imaging of secondary positive ions with a lateral resolution is better than 100 nm and large raster scale (until 400 x 400 mm) has been demonstrated on different samples like sea urchin and tree leaf (figure 2).
Refereed Scientific Publications:
- Imaging Chemical Patches on Near-surface Atmospheric Dust Particles with NanoSIMS 50 to Identify Material Sources. A. Krein, T. Udelhoven, J.-N. Audinot, C. Hissler, C. Guignard, L. Pfister, H.-N. Migeon and L. Hoffmann. Water Air Soil Pollut: Focus (2008) 8:495–503
- NanoSIMS 50 elucidation of the natural element composition in structures of cyanobacteria and their exposure to halogen compounds. T. Eybe, J.-N. Audinot, T. Bohn, C. Guignard, H.-N. Migeon, L. Hoffmann. Journal of Applied Microbiology (2008) Volume 105 Issue 5, 1502-1510
- Disconcerting accumulations in the core of hairs from Taklamakan desert mummies. P. Hallegot, P. Walter, M. Cotte, J.-N. Audinot, G. Guillot, H.-N. Migeon, E. Tallarek, B. Hagenhoff. Applied Surface Science 255 (2008)