Desorption electrospray ionization tissue imaging using heated nebulizing gas and high-resolution accurate mass spectra

A new method for tissue imaging using desorption electrospray ionization (DESI) mass spectrometry is described. The technique utilizes a DESI source with a heated nebulizing gas and high‐resolution accurate mass data acquired with an LTQ‐Orbitrap mass spectrometer. The two‐dimensional (2D) automated DESI ion source creates images using the ions that are collected under high‐resolution conditions. The use of high‐resolution mass detection significantly improves the image quality due to exclusion of interfering ions. The use of a heated nebulizing gas increases the signal intensity observed at lower gas pressure. The technique developed is highly compatible with soft tissue imaging due to the minimal surface destruction. Copyright © 2010 John Wiley & Sons, Ltd.