Paper – C60 versus Giant Clusters

Posted on by
Reply

Publication (SIMS XVIII Contribution):
Comparison of C60 and GCIB primary ion beams for the analysis of cancer cells and tumour sections
John S. Fletcher, Sadia Rabbani, Andrew M. Barber, Nicholas P. Lockyer, John C. Vickerman
Surf. Interface Anal. (2012)

Abstract

We have implemented a gas cluster ion beam (GCIB) system developed by Ionoptika Ltd (Southampton, UK) with sufficient control to allow us to exploit the unique capabilities of our J105 instrument for imaging and depth profiling. The J105 allows us to use the GCIB as continuous primary ion beam, thereby overcoming the issues associated with pulsing these slow moving, mixed species beams. We have performed a direct comparison with C60 ions on the same samples in the same instrument. The GCIB beams are more difficult to focus than the C60+ ion beam, making single-cell imaging difficult, although spot sizes of 15–20 µm are readily obtainable for Ar1000 and Ar2000, providing good resolution for larger area imaging on tissue section/biopsy samples. In this paper, we present results from the assessment of these new beams as primary ions for the analysis of ‘real’, complex biological systems. Initial spectra and those following increased primary ion bombardment were compared for in vitro cultured cells deposited on silicon and cryo-sectioned tumour samples originating in vivo. Ar1000+ and Ar2000+ showed increased persistence of the signals from intact molecular ions of phospholipids and a reduction in the accumulation of chemical background noise compared with C60+ analysis. Copyright © 2012 John Wiley & Sons, Ltd.

New student for 2012

Posted on by
Reply

We start 2012 by welcoming a new student to the group. Jo Denbigh joins us to work on a collaborative project with Roy Goodacre, Lipidomic and metabolomic imaging of biological response mechanisms.

Project Aim

To establish, using biological tissue sections and model organisms, perturbations in lipid and metabolite distributions as a consequence of pathological status or abiotic stress.  This will provide new insight into important biochemical processes associated with disease progression and environmental pollution.

Project Outline

Many diseases and abiotic stress responses are linked with abnormal lipid metabolism.  The chemical fingerprinting of diseased and stressed biological systems through lipidomics and metabolomics is a powerful approach to understanding and ultimately controlling biological function.  For example, drug development requires information on the biological response to therapy and the distribution of drugs and metabolites inside cells or tissues. Understanding and controlling the effect of environmental pollutants on fresh-water organisms is essential in protecting the eco-system. This project will address these issues through the application and methodological development of two emerging bioanalytical technologies, secondary ion mass spectrometry (SIMS) [1] and Raman microspectroscopy [2].  The systems to be studied include various biological tissues (diseased and healthy) and a fresh-water, single-celled microalgae Micrasterias hardyi.

Lipid profile in Micrasterias hardyi using FT-IR microspectroscopy (3)

  1. A New Dynamic in Mass Spectral Imaging of Single Biological Cells
    John S. Fletcher, Sadia Rabbani, Alex Henderson, Paul Blenkinsopp, Steve P. Thompson, Nicholas P. Lockyer, and John C. Vickerman
    Analytical Chemistry 80 (2008) 9058-9064
  2. Raman chemical mapping reveals site of action of HIV protease inhibitors in HPV16 E6 expressing cervical carcinoma cells
    D.-H. Kim, R.M. Jarvis, J.W. Allwood, G. Batman, R.E. Moore, E. Marsden-Edwards, L. Hampson, I.N. Hampson, R. Goodacre.
    Analytical and Bioanalytical Chemistry 398 (2010) 3051-3061
  3. Spatial metabolic fingerprinting using FT-IR spectroscopy: investigating abiotic stresses on Micrasterias hardyi
    S.A. Patel, F. Currie, N. Thakker and R. Goodacre
    Analyst 133 (2008) 1707-1713