Imaging Mass Spectrometry Method Development

In matrix-assisted laser desorption/ionization imaging mass spectrometry (MALDI IMS), a thinly sectioned tissue specimen is first mounted onto a flat substrate. The sample is then coated with a chemical matrix that has a strong absorbance at the wavelength of the MALDI laser to promote efficient desorption and ionization of molecular targets. A raster of the tissue surface is performed with the laser and mass spectra are collected at discrete x, y positions directly from the sample surface. Following data acquisition, maps of intensity are reconstructed for any ion of interest across the tissue. Our group is developing novel sample preparation strategies and instrumentation to improve imaging mass spectrometry figures of merit.