Skip to main content

Scanning electrochemical microscopy (SECM) and scanning ion conductance microscopy (SICM): new tools for the high resolution mapping of neuronal and glial activity

 Principal Supervisor: Professor Patrick R. Unwin, Department of Chemistry

Co-supervisor: Professor Bruno Frenguelli, School of Life Sciences

PhD project title: Scanning electrochemical microscopy (SECM) and scanning ion conductance microscopy (SICM): new tools for the high resolution mapping of neuronal and glial activity

University of Registration: University of Warwick

Project outline:

Scanning electrochemical microscopy (SECM) and scanning ion conductance microscopy (SICM) are functional probe-based techniques that offer extremely high spatial resolution of both the topography of surfaces and activity in terms of, for example, the flux of ions across cellular membranes. These techniques allow the investigation of single cells, groups of cells and cellular junctions and so are thus potentially powerful for addressing key issues for understanding neuronal activity.

We plan to use these techniques, on a multi-functional imaging platform, including the combination of multiple probe sensors and the integration of SECM/SICM with laser scanning confocal microscopy to map both the surface topography of neurones and glial cells, and also address fundamental questions regarding the utilisation of energy substrates such as glucose, lactate and pyruvate by these cells. These questions are of huge importance because the energy sources of these cells are not known, nor are the responses of the cells to different energy sources.

In addition, highly localised manipulations (with exquisite time resolution) of extracellular pH, oxygen and calcium ions will be possible, allowing the response of discrete neuronal and glial elements, such as postsynaptic dendritic spines, presynaptic boutons, and glial release sites, to be identified at unprecedented spatial resolution. These studies will significantly advance understanding of how these cells responds and adapt to transient perturbations in environment, providing an insight to early markers of disease states.

It is expected that this project will both provide answers to fundamental aspects of neuronal and glial signalling, and result in the development of equipment and analytical techniques, on a platform which is expected to be of wide applicability in the life sciences. As such, the project offers several avenues for important breakthroughs and will provide an experience and training on significant future techniques.

References:

  • Page A, Perry D, Young P, Mitchell D, Frenguelli BG, Unwin PR. Fast Nanoscale Surface Charge Mapping with Pulsed-Potential Scanning Ion Conductance Microscopy. Anal Chem. 2016 Nov 15;88(22):10854-10859.
  • Perry D, Paulose Nadappuram B, Momotenko D, Voyias PD, Page A, Tripathi G, Frenguelli BG, Unwin PR. Surface Charge Visualization at Viable Living Cells. J Am Chem Soc. 2016 Mar 9;138(9):3152-60.
  • McKelvey K, Kinnear SL, Perry D, Momotenko D, Unwin PR. Surface charge mapping with a nanopipette. J Am Chem Soc. 2014 Oct 1;136(39):13735-44.
  • Actis P, Tokar S, Clausmeyer J, Babakinejad B, Mikhaleva S, Cornut R, Takahashi Y, López Córdoba A, Novak P, Shevchuck AI, Dougan JA, Kazarian SG, Gorelkin PV, Erofeev AS, Yaminsky IV, Unwin PR, Schuhmann W, Klenerman D, Rusakov A, Sviderskaya EV, Korchev YE. Electrochemical nanoprobes for single-cell analysis. ACS Nano. 2014 Jan 28;8(1):875-84.
  • Takahashi Y, Shevchuk AI, Novak P, Babakinejad B, Macpherson J, Unwin PR, Shiku H, Gorelik J, Klenerman D, Korchev YE, Matsue T. Topographical and electrochemical nanoscale imaging of living cells using voltage-switching mode scanning electrochemical microscopy. Proc Natl Acad Sci U S A. 2012 Jul 17;109(29):11540-5.
  • Takahashi Y, Shevchuk AI, Novak P, Zhang Y, Ebejer N, Macpherson JV, Unwin PR, Pollard AJ, Roy D, Clifford CA, Shiku H, Matsue T, Klenerman D, Korchev YE. Multifunctional nanoprobes for nanoscale chemical imaging and localized chemical delivery at surfaces and interfaces. Angew Chem Int Ed Engl. 2011 Oct 4;50(41):9638-42.

BBSRC Strategic Research Priority: Molecules, Cells and Systems  

Techniques that will be undertaken during the project:

  • Cell culture
  • Scanning electrochemical microscopy (SECM) and scanning ion conductance microscopy (SICM)
  • Electrophysiology
  • Quantitative biology

Contact: Professor Patrick R. Unwin, Department of Chemistry