Small Molecule Drug Imaging of Mouse Tissue by MALDI-TOF/TOF Mass Spectrometry and FTMS

Matrix Assisted Laser Desorption Ionization (MALDI) Mass Spectrometry (MS) with a computer-controlled xy-stage in the ionization source can be used to detect the presence, approximate amount and location of small molecules, lipids, peptides and proteins in tissue samples through in vitro molecular imaging, often referred to as MALDI imaging. Both MALDI Time-of-flight/Time-of-flight (MALDI-TOF/TOF MS) and MALDI Fourier Transform Mass Spectrometry (FTMS) were used to detect and image the location of Erlotinib in various mouse tissues. The molecular imaging experiments not only indicated where in the mouse’s body the drug accumulated, but it also gave insight regarding the different MALDI imaging technologies’ respective capabilities for small molecule drug tissue imaging.