PROMOTED: A Novel Coupling of MALDI Imaging and Fast QCL-Based IR Imaging for Disease Detection

Matrix-assisted laser desorption/ionization (MALDI) imaging is a powerful mass spectrometry-based approach that allows for the simultaneous detection of hundreds of biomolecules from one tissue section in one experiment. The addition of ion mobility separation techniques such as TIMS provide real-time orthogonal separation of isomeric and isobaric compounds that allow for even greater molecular information from MALDI imaging experiments. However, because MALDI data acquisition occurs pixel-by-pixel, acquisition time remains unrealistic for entire tissue sections at high spatial resolution such as five µm. IR imaging, in contrast, is a non-destructive, non-contact, label-free approach that can provide global molecular information readily and achieve high spatial resolution imaging.

Tague shares an IR-guided workflow for targeted MALDI imaging. In this workflow tissue samples would be analyzed by rapid IR imaging and if they were negative for disease detection, they would be subsequently analyzed by the more time-consuming but more sensitive MALDI imaging. Previously, the possible applicability of vibrational microscopy to this potential workflow was limited by the extensive acquisition and analysis time necessary to obtain high-resolution chemical images.

Now, with the maturity of quantum cascade lasers (QCL), fast spectroscopic IR laser imaging can be conducted so that complete tissue sections can be analyzed in a matter of minutes. Since millions of spectra are collected during these acquisitions, novel machine learning based algorithms have also been employed to facilitate data analysis that allows the use of fast QCL-based laser imaging to be used for screening tissue samples for possible MALDI imaging.

About the presenter
Thomas Tague, Ph.D., is the applications manager for Bruker Corporation. He is also a member of the visiting advisory committee of the Metropolitan Museum of Art in New York and the Advisory Board of Amplified Sciences. Tague received his doctorate from the University of Utah in chemistry and his Bachelor of Science degree, also in chemistry, from the University of Texas at San Antonio.

He conducted his postdoctoral research at the University of Virginia working with Professor Lester Andrews. He is a member of the American Chemical Society, Society for Applied Spectroscopy, American Physical Society, and the Optical Society of America. Tague is active in developing new methods and instrumentation with the goal of improving the sensitivity and detection limits of spectroscopy related applications. He has more than 90 publications and five patents.