title: Modifications to a commercially available linear mass spectrometer for mass-resolved microscopy with the pixel imaging mass spectrometry (PImMS) camera.
abstract: BACKGROUND
  Imaging mass spectrometry is a powerful analytical technique capable of accessing a large volume of spatially resolved, chemical data from two-dimensional samples. Probing the entire surface of a sample simultaneously requires a detector with high spatial and temporal resolutions, and the ability to observe events relating to different mass-to-charge ratios.
  
  
  METHODS
  A commercially available time-of-flight mass spectrometer, designed for matrix-assisted laser desorption/ionization (MALDI) analysis, was combined with the novel pixel imaging mass spectrometry (PImMS) camera in order to perform multi-mass, microscope-mode imaging experiments. A number of minor modifications were made to the spectrometer hardware and ion optics so that spatial imaging was achieved for a number of small molecules.
  
  
  RESULTS
  It was shown that a peak width of Δm50 %  <  1  m/z unit across the range 200 ≤ m/z  ≤  800 can be obtained while also achieving an optimum spatial resolution of 25 µm. It was further shown that these data were obtained simultaneously for all analytes present without the need to scan the experimental parameters.
  
  
  CONCLUSIONS
  This work demonstrates the capability of multi-mass, microscope-mode imaging to reduce the acquisition time of spatially distributed analytes such as multi-arrays or biological tissue sections. It also shows that such an instrument can be commissioned by effecting relatively minor modifications to a conventional commercial machine.
authors: The Department of Chemistry, University of Oxford, The Physical and Theoretical Chemistry Laboratory, South Parks Road, Oxford, OX1 3QZ, UK.
authors: E
authors: E
authors: Halford
authors: B
authors: B
authors: Winter
authors: M D
authors: MD
authors: Mills
authors: S P
authors: SP
authors: Thompson
authors: V
authors: V
authors: Parr
authors: J J
authors: JJ
authors: John
authors: A
authors: A
authors: Nomerotski
authors: C
authors: C
authors: Vallance
authors: R
authors: R
authors: Turchetta
authors: M
authors: M
authors: Brouard
mesh_terms: D004867:Equipment Design; D019544:Equipment Failure Analysis; D015902:Gamma Cameras; D007089:Image Enhancement / Q000295:instrumentation*; D008853:Microscopy / Q000295:instrumentation*; D057054:Molecular Imaging / Q000295:instrumentation*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012815:Signal Processing, Computer-Assisted / Q000295:instrumentation*