ELECTRICAL AND FLUIDIC CHARACTERIZATION OF A NOVEL INTEGRATED SYSTEM FOR AUTOMATIC PATCH-CLAMP ON CULTURED NEURAL NETWORKS
From LabAutopedia
ELECTRICAL AND FLUIDIC CHARACTERIZATION OF A NOVEL INTEGRATED SYSTEM FOR AUTOMATIC PATCH-CLAMP ON CULTURED NEURAL NETWORKS
Massimo Alberti, Detlef Snakenborg, Joanna M. Lopacinska, Martin Dufva and Jörg P. Kutter
Department of Micro and Nanotechnology, Technical University of Denmark, DENMARK
A planar patch-clamp system for automatic electrophysiological measurements on cells in culture is a challenging task for microtechnology and a powerful framework for neuroscience research and drug screening.
The patch-clamp technique is the gold standard electrophysiological method for investigating ion-channel-related events in cells and neurons. Traditional patch-clamping requires highly trained personnel and specialized laboratories and it has a very low throughput; on the other hand, commercially available patch-clamp-on-a-chip systems only perform analysis on individual cells and require cells to be in suspension.
Cells behave different if left in suspensions or allowed to grow and differentiate: to study a cell in a cell culture means studying also the cell-cell interactions; this is extremely relevant in a neuronal network, where signal transmission and communication pathways strongly determine the network behavior.
We are developing a prototype system to perform simultaneous planar patch-clamping on cultured cells or neuronal networks, which combines the potential of patch-clamping with the multielectrode array (MEA) concept. By offering the possibility to perform, at the same time, high-throughput and high-content analysis, we expect to provide a system and a method useful both to neurobiologists (for signal transmission investigations) and to drug developing companies, for shortening the secondary screening assays.
We fabricated and packaged an individually addressable patch-clamp micro-channel array (PCµCA) through a modular approach. The main component is the disposable Si/SiO2 microstructured chip resembling the patch-clamp pipettes, where six apertures (2-3 m diameter) regularly spaced (400 m) are individually addressed by six microchannels created on the opposite side.
The system has been fluidically characterized as a perfusion system. Electrochemical impedance spectroscopy (EIS) has been used for electrical characterization: resistance values of 3 to 10 MΩ and a capacitance of 95 pF were measured. Cell trapping by suction and preliminary analysis on HeLa and PC12 cells have been performed.
We showed that, thanks to its simple and essential design, the microstructured Si/SiO2 chip can provide a versatile basic platform for many different investigative methods and applications, featuring at the same time a precise local perfusion dispenser, a cell-trapping system, a patch-clamp-on-a-chip, a multi-electrode array (MEA) and a biosensor.
