title: Novel Sample Preparation Technique To Improve Spectromicroscopic Analyses of Micrometer-Sized Particles.
abstract: Microscale processes occurring at biogeochemical interfaces in soils and sediments have fundamental impacts on phenomena at larger scales. To obtain the organo-mineral associations necessary for the study of biogeochemical interfaces, bulk samples are usually fractionated into microaggregates or micrometer-sized single particles. Such fine-grained mineral particles are often prepared for nanoscale secondary ion mass spectroscopy (NanoSIMS) investigations by depositing them on a carrier. This introduces topographic differences, which can strongly affect local sputtering efficiencies. Embedding in resin causes undesired C impurities. We present a novel method for preparing polished cross-sections of micrometer-sized primary soil particles that overcomes the problems of topography and C contamination. The particles are coated with a marker layer, embedded, and well-polished. The interpretation of NanoSIMS data is assisted by energy-dispersive X-ray spectroscopy on cross-sections prepared by a focused ion beam. In the cross-sections, organic assemblages on the primary soil particles become visible. This novel method significantly improves the quality of NanoSIMS measurements on grainy mineral samples, enabling better characterization of soil biogeochemical interfaces. In addition, this sample preparation technique may also improve results from other (spectro-) microscopic techniques.
authors.affiliation: †Lehrstuhl für Bodenkunde, Department Ecology and Ecosystem Management, Center of Life and Food Sciences Weihenstephan, Technische Universität München, 85354 Freising-Weihenstephan, Germany.
authors.forename: Carmen
authors.initials: C
authors.lastname: Höschen
authors.affiliation: ‡Max-Planck-Institut für Plasmaphysik, 85748 Garching, Germany.
authors.forename: Till
authors.initials: T
authors.lastname: Höschen
authors.affiliation: †Lehrstuhl für Bodenkunde, Department Ecology and Ecosystem Management, Center of Life and Food Sciences Weihenstephan, Technische Universität München, 85354 Freising-Weihenstephan, Germany.
authors.forename: Carsten W
authors.initials: CW
authors.lastname: Mueller
authors.affiliation: †Lehrstuhl für Bodenkunde, Department Ecology and Ecosystem Management, Center of Life and Food Sciences Weihenstephan, Technische Universität München, 85354 Freising-Weihenstephan, Germany.
authors.forename: Johann
authors.initials: J
authors.lastname: Lugmeier
authors.affiliation: ‡Max-Planck-Institut für Plasmaphysik, 85748 Garching, Germany.
authors.forename: Stefan
authors.initials: S
authors.lastname: Elgeti
authors.affiliation: †Lehrstuhl für Bodenkunde, Department Ecology and Ecosystem Management, Center of Life and Food Sciences Weihenstephan, Technische Universität München, 85354 Freising-Weihenstephan, Germany.
authors.forename: Thilo
authors.initials: T
authors.lastname: Rennert
authors.affiliation: †Lehrstuhl für Bodenkunde, Department Ecology and Ecosystem Management, Center of Life and Food Sciences Weihenstephan, Technische Universität München, 85354 Freising-Weihenstephan, Germany.|||Institute for Advanced Study, Technische Universität München, 85748 Garching, Germany.
authors.forename: Ingrid
authors.initials: I
authors.lastname: Kögel-Knabner
mesh_terms: D053000:Analytic Sample Preparation Methods; D008853:Microscopy / Q000379:methods*; D053758:Nanoparticles / Q000737:chemistry / Q000648:ultrastructure; D055620:Optical Phenomena; D010316:Particle Size; D012987:Soil / Q000737:chemistry; D018629:Spectrometry, Mass, Secondary Ion; D013057:Spectrum Analysis / Q000379:methods*
chemical_list: D012987:Soil