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Mapping Antiretroviral Drugs in Tissue by IR-MALDESI MSI Coupled to the Q Exactive and Comparison with LC-MS/MS SRM Assay

  • Jeremy A. Barry
  • Guillaume Robichaud
  • Mark T. Bokhart
  • Corbin Thompson
  • Craig Sykes
  • Angela D. M. Kashuba
  • David C. MuddimanEmail author
Focus: Advancing High Performance Mass Spectrometry: Research Article

Abstract

This work describes the coupling of the IR-MALDESI imaging source with the Q Exactive mass spectrometer. IR-MALDESI MSI was used to elucidate the spatial distribution of several HIV drugs in cervical tissues that had been incubated in either a low or high concentration. Serial sections of those analyzed by IR-MALDESI MSI were homogenized and analyzed by LC-MS/MS to quantify the amount of each drug present in the tissue. By comparing the two techniques, an agreement between the average intensities from the imaging experiment and the absolute quantities for each drug was observed. This correlation between these two techniques serves as a prerequisite to quantitative IR-MALDESI MSI. In addition, a targeted MS2 imaging experiment was also conducted to demonstrate the capabilities of the Q Exactive and to highlight the added selectivity that can be obtained with SRM or MRM imaging experiments.

Key words

IR-MALDESI Mass spectrometry imaging LC-MS/MS Drug distribution 

Notes

Acknowledgments

The author gratefully acknowledge the assistance of Kerstin Strupat from Thermo Scientific as well as the financial support received from the National Institutes of Health (R01GM087964), U01AI095031, P30AI050410, U19AI096113, GlaxoSmithKline, the William R. Kenan, Jr. Fund for Engineering, Technology, and Science, the W. M. Keck Foundation, and North Carolina State University.

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Copyright information

© American Society for Mass Spectrometry 2014

Authors and Affiliations

  • Jeremy A. Barry
    • 1
  • Guillaume Robichaud
    • 1
  • Mark T. Bokhart
    • 1
  • Corbin Thompson
    • 2
  • Craig Sykes
    • 2
  • Angela D. M. Kashuba
    • 2
  • David C. Muddiman
    • 1
    Email author
  1. 1.W. M. Keck FT Mass Spectrometry Laboratory, Department of ChemistryNorth Carolina State UniversityRaleighUSA
  2. 2.Eshelman School of PharmacyThe University of North CarolinaChapel HillUSA

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