SIMS and Pharmacy talk

Nick gave an invited talk on Imaging Biosystems using Secondary Ion Mass Spectrometry to industrialists and academics at the Royal Society of Chemistry in London, organised by the Joint Pharmaceutical Analysis Group and The Drug Metabolism Discussion Group.  The title of the meeting was ‘New approaches in bioanalysis and analytical toxicology’.

 Abstract

The application of imaging time-of-flight secondary ion mass spectrometry (ToF-SIMS), for 2D and 3D molecular characterisation on the micron scale has been made possible by the introduction of cluster/polyatomic primary ion beams [1,2].  These beams enhance the molecular sputter yield by orders of magnitude compared to their atomic counterparts.  In the case of polyatomic sputtering using e.g. C60+ or Ar1000+, the chemical damage to the surface is significantly reduced allowing analysis beyond the so-called ‘static limit’, which previously has hampered high resolution molecular imaging.  However, the optimum application of polyatomic ion beams for 2D and 3D molecular imaging under high dose conditions requires a new paradigm allowing quasi-continuous analysis.

Here we present a range of imaging data from biological tissue and single cells to illustrate the capabilities of a novel ToF-SIMS instrument [3], designed for optimum molecular imaging using quasi-continuous polyatomic sputtering.   Our preliminary work has suggested that in the area of small molecule imaging with good (cellular scale) resolution, ToF-SIMS is potentially a valuable tool that can complement other chemical imaging technologies such as fluorescence, MALDI and Raman spectroscopy [4].  This presentation will provide an overview of these preliminary studies, as we aim to establish the current capabilities of the technique and identify challenge areas for future development.  Examples include the analysis of Alzheimer diseased brain tissue, frog zygotes and multicellular tumour spheroids [5-7].

  1. J.S. Fletcher, N.P. Lockyer, J.C. Vickerman,  Mass Spectrom. Rev. 30 (2011) 142-174.
  2. F. Benabdellah, A. Seyer, L. Quinton, D. Touboul, A. Brunelle, O. Laprévote, Anal. Bioanal. Chem. 396 (2010)151–162.
  3. J.S. Fletcher, S. Rabbani, A. Henderson, P. Blenkinsopp, S.P. Thompson, N.P. Lockyer, J.C. Vickerman, Anal. Chem. 80 (2008) 9058–9064.
  4. N.P. Lockyer Bioanalysis 3 (2011) 1047-1051.
  5. E.G. Armitage, H.L. Kotz, N. P. Lockyer, Metabolomics 9 (2012) 102-109.
  6. H.L. Kotze, E.G. Armitage, J.S. Fletcher, A. Henderson, K.J. Williams, N.P. Lockyer and J.C. Vickerman Surf. Interface Anal. 45 (2012) 277-281.
  7. E.G Armitage, H.L Kotze, J.S Fletcher, A. Henderson, K.J Williams, N.P Lockyer and J.C Vickerman Surf. Interface Anal. 45 (2012) 282-285.