Electrochemistry and Mass Spectrometry Imaging in Flies, Cells, and Vesicles

Andrew Ewing
Andrew Ewing
Univ. of Gothenburg and Chalmers Univ. of Technology, Sweden
14:00~14:45,November 20th, 2015


Electrochemical methods provide a powerful approach to investigate neurotransmitter release and storage from and in single cells. Additionally, the fly model (Drosophila melanogaster) provides a unique system to examine neurotransmitter release and drug dependence mechanisms in a small, but complete system.

We have developed new electrochemical arrays at extremely small size scale for imaging exocytotic release across single cells. The electrode arrays have been made both under the cells and in a probe format. We can use computer modeling of responses to image release sites with approximately 100 nm spatial resolution.

Mass spectrometry imaging with ion beams allows spatial resolution of a few micrometers down to 40 nanometers in favorable cases. We have been using secondary ion mass spectrometry (SIMS) with a unique 40-kV argon cluster ion source and the NanoSIMS to measure the lipids across the fly brain and catecholamine in nanometer vesicles, respectively. Here, we have focused on the effect of the drug, methylphenidate, on lipid composition in the brain and find that it varies in a way that might affect cognition. We have also used NanoSIMSs to measure transmitter in subregions of nanometer vesicles. Combined with electrochemical cytometry to monitor the content of the interior of vesicles, we have begun to investigate the details and implications of open and closed exocytosis.


Honors & Prizes:


  • 1987 NSF Presidential Young Investigator Award
  • 1989 Alfred P. Sloan Research Fellowship
  • 1989 Camille and Henry Dreyfus Teacher-Scholar Award
  • 1994 The Penn State Faculty Scholar Medal in Physical Sciences and Engineering
  • 1997 The Penn State Graduate Faculty Teaching Award
  • 1999 The John Simon Guggenheim Memorial Foundation Fellowship
  • 1999 Award for Outstanding Achievements in the Field of Capillary Electrophoresis
  • 2000 A. A. Benedetti-Pichler Award, American Microchemical Society
  • 2001 Distinguished Alumni Citation, Saint Lawrence University
  • 2001-2002 Special Creativity Extension, National Science Foundation
  • 2004 Elected Fellow of American Association for Advancement of Science
  • 2006 Eastern Analytical Symposium Award for Outstanding Achievements in the Fields of Analytical Chemistry
  • 2006 American Chemical Society Analytical Division Award for Chemical Instrumentation
  • 2007-2010 European Union Marie Curie Chair
  • 2009 Fellow, Royal Society of Chemistry, FRSC
  • 2001 European Research Council (ERC) Advanced Grant, 25 000 000 SEK
  • 2001 Appointed Wallenberg Scholar, 15 000 000 SEK
  • 2012 Elected to Swedish Academy of Sciences (Academician), Chemistry Class
  • 2013 Charles N Reilley Award in Electroanalytical Chemistry
  • 2013 American Chemical Society Analytical Division Award in Electrochemistry
  • 2013 Elected to the Gothenburg Academy of Arts and Sciences
  • 2014 Honorary Professor, Nanjing University of Science and Technology
  • 2014 Norblad-Ekstrand Medal of the Swedish Chemical Society
  • 2014 Honorary Professor, University of Science and Technology Beijing
  • 2015 Society for Analytical Chemists of Pittsburgh Award in Analytical Chemistry

Professional Activities:


  • 1984-1992 Assistant/Associate Professor, Penn State University
  •  1990-1995 Assistant Head of Department, Director of Graduate Education, Penn State
  • 1992-2010 Professor of Chemistry, Penn State University
  • 1995-2003 Adjunct Professor of Neuroscience and Anatomy, Penn State University
  • 1996-2000 Co-Director, Neuroscience Option, Integrative Biosciences Graduate Program
  • 1999-2010 J. Lloyd Huck Chair in Natural Sciences, Penn State University
  • 1990-2004 Head, Department of Chemistry, Penn State University
  • 2003-2010 Professor of Neural and Behavioral Sciences, Penn State University
  • 2007-2010 Marie Curie Chair, Dept. of Chemistry, University of Gothenburg
  • 2010- Appointed Professor of Analytical Chemistry, University of Gothenburg
  • 2010-2012 Adjunct Professor, Department of Chemistry, Penn State University
  • 2011- Chair (Professor), Analytical Chemistry, Chalmers University of Technology
  • 2011- Director, Joint Chalmers-GU Initiative for Bioanalytical Chemistry