Details of Award
NERC Reference : NE/J013382/1
Developing methods for mass spectral imaging of environmental samples
Grant Award
- Principal Investigator:
- Dr JG Bundy, Imperial College London, Surgery and Cancer
- Co-Investigator:
- Dr DS McPhail, Imperial College London, Materials
- Co-Investigator:
- Dr s fearn, Imperial College London, Materials
- Grant held at:
- Imperial College London, Surgery and Cancer
- Science Area:
- Terrestrial
- Overall Classification:
- Terrestrial
- ENRIs:
- Biodiversity
- Pollution and Waste
- Science Topics:
- Analytical Science
- Mass Spectrometry
- Materials Characterisation
- Secondary Ion Mass Spectrom.
- Pollution
- Abstract:
- The ability to create an image is fundamental to advancing scientific understanding. This is true at all scales - for instance, it is immediately obvious how a pollution map could be used to visualize and understand environmental threats. At the small scale as well, the ability to image individual cells and parts of cells is an essential part of modern science. There are well-established techniques to image large molecules (genes and proteins) in a biological sample, but this is much less routine for smaller things such as metabolites, metal ions, or molecules of chemical pollutants. One technique that can do this is secondary ion mass spectrometry (SIMS), in which a beam of ions (charged particles) is played across a sample. This produces secondary ions from its surface, which are collected and fed into a mass spectrometer, which sorts and counts them. The signal can then be interpreted to give you not only a detailed image of the sample, but also information about its chemical composition. There are a number of different kinds of SIMS instrument, and one in particular, the Ion-Tof TOF-SIMS (standing for time-of-flight SIMS) has very high resolution in two different ways. Firstly, the detector (mass spectrometer) is high resolution, so that it can distinguish two different signals that a traditional instrument would lump together. Secondly, it has very high spatial resolution: it can easily create detailed images of something the size of a single cell, and resolve sub-cellular structures. This means that it has immense potential for studying the biochemistry of surfaces - for instance, a slice through a cell or tissue. It can also work just as well with non-model ecologically relevant organisms, particularly important for environmental research. However, there are many factors that could affect the potential quality of images produced by TOF-SIMS. In particular, how you prepare a sample to go into the instrument is likely to be crucial. We propose to demonstrate the versatility and utility of TOF-SIMS for environmental research by applying it to three contrasting exemplar projects: 1. Imaging metal ions at a sub-cellular distribution in samples from woodlice. Woodlice are common terrestrial invertebrates, and their responses to pollution can tell us about the ecological health of a contaminated site. Two different woodlouse species handle the toxic metals lead and zinc very differently, and we will generate detailed maps of exactly where these metals are found within their cells. We may also be able to determine what kind of complexes these metal ions form. 2. Imaging nanoparticles in earthworms. The potential toxicity of very small particles - nanoparticles - is not at all well understood, so is a current hot research topic. It's obviously vital to be able to identify where they end up in a biological sample, but this is challenging. We will use TOF-SIMS as a complementary analysis for samples of nanoparticles in earthworms, generated from a separate project. 3. Imaging a unique earthworm metabolite. Earthworms are a common soil animal, and play a key role in maintaining soil quality. They produce a unique chemical, and no-one knows exactly what for. It's present in all earthworm species, so must play an important biological role: our best guess is that it helps them to survive desiccation when soil dries out, by helping stabilize membranes. We will produce a detailed map of where this chemical is found in earthworm cells, the first crucial step in understanding just what it does. Thus, our project aims to provide a proof-of-principle for using TOF-SIMS in environmental research. For projects 1 and 2 above, we will be able to make a direct comparison to imaging data acquired (by a collaborating lab) at the Diamond synchrotron (a huge, complex, specialist facility): we expect the TOF-SIMS will have many advantages, such as higher-resolution images, at a fraction of the cost and complexity.
- NERC Reference:
- NE/J013382/1
- Grant Stage:
- Completed
- Scheme:
- Small Grants (FEC)
- Grant Status:
- Closed
- Programme:
- Small Grants
This grant award has a total value of £51,686
FDAB - Financial Details (Award breakdown by headings)
| DI - Other Costs | Indirect - Indirect Costs | DA - Investigators | DA - Estate Costs | DI - Staff | DI - T&S | DA - Other Directly Allocated |
|---|---|---|---|---|---|---|
| £4,960 | £18,106 | £4,671 | £7,053 | £15,894 | £600 | £402 |
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