Nano scale Secondary Ion Mass Spectrometry is a high resolution isotope and elemental imaging technique for solid sample surfaces.
- Mass range – 1H to 238U
- Sensitivity – PPB depending on ion and matrix
- Resolution – as low as ~40nm
- High mass resolution
What can nanoSIMS do?
NanaoSIMS analysis can be used to observe natural or altered surface chemistry elements (specific isotopes) at low concentrations and at high resolution. Below are links to recent applications of nanoSIMS analysis in various disciples;
Our fundamental aim is to make nanoSIMS analysis available for any relevant academic or commercial interest and generate high quality data that best answers the ‘questions’ they come with. Our many years of experience working on projects from diverse fields of science enables us to maximize the potential of cutting edge nanoSIMS analysis for your project.
We want your project to succeed meaning we insist on understating your project needs in detail before we begin analysis. We will assist at every stage from experimental design to sample preparation to data analysis and interpretation.
Our experienced team have assisted many research projects from inception through to output – be that scientific publication or a detailed commercial report. Every project is unique in some way and will pose a different set of challenges (see below).
Correct preparation of samples is the single most important part of successful and meaningful nanoSIMS analysis. This includes how the samples are physically prepared and also the need for suitable controls. Samples need to be flat, conductive, dry and able to withstand high vacuum. How this is achieved will depend upon the sample of interest and will differ between projects, i.e., a meteorite samples will differ substantially to a cell line labeled with an isotopically enriched tracer. We suggest contacting us for advice or consulting publications focused on analogous sample types.
Data analysis and interpretation
We constantly monitor data during analysis so as to provide consistent high quality results. Once happy with the ‘raw’ data, we will guide users through data analysis processes to generate the output they desire. Generating, processing and displaying data differs for every project, so it is our goal to provide the tools appropriate to best achieve desired outcomes. For ease of use, we recommend using the OpenMIMS plugin associated with Image J software for initial data extraction and analysis (see Useful links).
The University of western Australia house the only nanoSIMS instruments in Australia. The two Cameca built instruments are fundamentally the same, except the newer 50L model has some useful upgrades and increased capability.
Cameca NanoSIMS 50
- Cs+ sources to <50nm resolution – only detects negative ion species
- Multicollection: one Faraday cup, five electron multipliers
- Electron gun for charge compensation
- Secondary electron detector
Cameca NanoSIMS 50L
- Cs+ and O- ion sources to <50nm resolution (O- source is latest generation RF plasma source)
- Multicollection: seven Faraday cups, seven electron multipliers
- Improved mass separation
- Electron gun for charge compensation
- Secondary electron detector
- Nuclear magnetic resonance (NMR) magnet control
How much does analysis cost?
Researchers from academic institutions (UWA, other Australian universities and international universities) all pay $75 per hour. Minimum usage is 8 hours, but we find most projects tend to occur over week long blocks. We also charge a one time admin fee ($250 for UWA, $500 others). Commercial projects have a different pricing schedule available on request.
How long will analysis take?
This is dependent upon sample numbers, replication, sample size, ion concentrations, matrix effects, standard requirements etc. We will apply our experience to guide users as best as possible given their requirements.
What is the wait time until analysis?
Wait time is usually a few weeks to a few months from receipt of samples. This will depend on instrument demand, project size, instrument maintenance/downtime.
How do I prepare my samples?
Depends on sample type and research aims. The main characteristics of nanoSIMS ready samples are that they have a flat surface, are conductive (can be metal coated) and able to withstand high vacuum (dry). We have a range of sample holders designed to accommodate thin silicon wafers (Ideal for mounting resin embedded sections), polished resin discs (10, 12, 15mm diameter), TEM grids or square microscope slides.
Can I be present during analysis?
Yes. Because of the complexity involved in nanoSIMS operation, all analyses are performed by inhouse staff. We are more than happy to have you present as this often makes it easier for selecting specific analysis areas or tweaking experimental plans as we go. Alternately, if you are unable to accompany your samples, they can be sent to us and we will analyse after consultation with you. Another option is to come for the start of analysis and leave when you are satisfied everything is proceeding well. The choice is yours!
Where do I start?
- Define a robust aim or hypothesis for your research.
- Consult the literature for analogous analyses and try to understand the science and potential of nanoSIMS.
- Determine if nanoSIMS is the correct method for your research.
- Contact us with your ideas (at any stage)—we have lots of experience and are here to help.
Is nanoSIMS analysis right for my research?
Ultimately, it comes down to a question of resolution required and concentration of the ion(s) of interest. The schematic below is a simple comparison of analogous methods and shows why nanoSIMS may be a more/less appropriate technique than others. NanoSIMS is a particularly powerful method for analyzing and imaging micro scale heterogeneity of different ions. We are happy to discuss whether (or not) nanoSIMS is right for your research.
NanoSIMS analysis has proven very useful for studying environmental processes, both biotic and abiotic. The ability to observe natural element and isotope abundance as well as the potential to observe added specific isotope tracers has been employed in a diverse range of studies ranging from marine to cosmochemistry applications.
The example here is nanoSIMS acquired images comparing nitrate uptake (24 hours incubation with 15NO3) by coral (Stylophora pistillata) and its algal symbiont growing at normal temperature (top) and heat stressed (bottom; after 10 days). Left images are 12C14N ion images, useful for ultrastructural detail; and right are 15N/14N overlayed ion images showing points of 15N enrichment (0.37 atom % is natural abundance). Scale bar 5 um.
The potential of nanoSIMS analysis in medical research is highlighted in the schematic below - a Bromine labeled nucleic acid based therapeutic (modified antisense oligonucleotide, ASO) is ingested by mouse and distribution of ASO in various tissue types is observed at the subcellular level. There is potential to modify this system with the addition of any isotopically labeled molecule.
NanoSIMS analysis in geological applications has proved to be a versatile technique to investigate microscale elemental and isotopic profiling of a whole range of sample types. The example below, ancient pyrite grains, demonstrates how elemental (top) and isotopic (bottom) information can be extracted from very small samples at very high resolution and how this information can be linked to specific ultrastructure.
Application of nanoSIMS analysis for materials science is diverse and to date has been used for ‘quality control’ and understanding microscale compositional attributes of certain products. Samples have included everything from steel alloys to solar cells. NanoSIMS allows for simultaneous analysis of elemental and isotopic compositions specific to research requirements. Depth profiles of sample chemistry can be generated by analysing over and over a defined raster area.
Example 2 – depth profiling of a solar cell.