Paolo Olivero (Dipartimento di Fisica)
Federico Picollo (Dipartimento di Fisica)
Ettore Vittone (Dipartimento di Fisica)
Members of other units:
Alberto Pasquarelli (Univ. Ulm, Germany)
Nanocrystalline diamond (NCD) surfaces covered with adhesion proteins offer outstanding features for interfacing excitable cells and constructing microelectrode arrays (MEAs) able to detect electrical events, optical signals and “quanta” of neurotransmitter molecules released from neurons and neurosecretory cells. In collaboration with the Department of Physics (http://www.dfs.unito.it/solid/RICERCA/ricerca.html), the University of Ulm http://www.uni-ulm.de/einrichtungen/saps/studiengaenge/sensorsystemtechnik/dozenten.htm), in this project we intend to develop a new generation of diamond-based microchips able to detect the electrical activity generated by neurons and other excitable cells and test their functionality and biocompatibility. These new lab-on-chips will offer the possibility to record different biological signals simultaneously from the same cell (extracellular recorded depolarisation, calcium transients, neurotransmitter release) in contrast to traditional MEAs able to detect only electrical signals related to cell’s excitability.
We expect to improve the 2x2 boron-doped NCD-MEA developed in collaboration with Dr. Pasquarelli’s group (Univ. Ulm, Germany) (Carabelli et al., 2010) following two main strategies by constructing: i) a 3x3 MEA covering the total area of a single cell to be used for monitoring secretion in cell microdomains, and ii) a 4x4 MEA of 20 μm diameter separated by 200 μm distance. This new microarray will detect amperometric signals associated with released neurotransmitters, electrical events and fluorescence Ca2+ signals from neuronal networks grown on the surface.
The functional properties of the monocrystalline diamond microchips with a single conductive graphitic pathway recently developed in collaboration with Dr. Olivero’s group (Dept of Physics, Torino) (Picollo et al., 2013) will be also improved to form an array of 4x4 graphitic channels similar to the planned boron-doped chips. These new diamond-based biosensors may overcome most of the intrinsic limitations of commercially available MEAs and offer the possibility of multi-parametric analysis on neuronal, cardiac and neuroendocrine cells.
- Carabelli V et al., 2010. Nanocrystalline diamond microelectrode arrays fabricated on sapphire technology for high-time resolution of quantal catecholamine secretion from chromaffin cells.Biosensors & Bioelectronics 26: 92-98
- Picollo F, Gosso S et al., 2013. A new diamond biosensor with integrated graphitic microchannels for detecting quantal exocytic events from chromaffin cells Advanced Materials (in press)
Microelectrode arrays (MEAs),Diamond-based microchips, Action potential recordings, Amperometric signals, Neuronal networks, Drug-screening, Sino-atrial node, Chromaffin cells, Fluorescence microscope, Calcium signaling, Calcium imaging