Category: Assay Development and Screening

1329-E - Introducing Maestro Pro and Maestro Edge: next-generation microelectrode array platforms for high-throughput electrophysiology

Wednesday, February 7, 2018
11:30 AM - 12:30 PM

Multiwell microelectrode array (MEA) technology has been adopted for applications in drug safety, stem cell development, and disease-in-a-dish modeling.  The technology enables electrophysiological measurements of neural and cardiac cell culture models in vitro, as the electro-active cells directly interface with electrodes embedded in the substrate of tissue culture microplates.  Although the fundamentals of MEA technology are established, recent deployment of the MEA assay in a screening context emphasizes the utility and need for improved experimental and analytical methods.

The Maestro Pro and Maestro Edge multiwell MEA platforms (Axion BioSystems) were developed to streamline the acquisition and analysis of electrophysiological signals from neurons and cardiomyocytes cultured multiwell MEA plates (Axion BioSystems).  The Maestro Pro acquires data from 768 electrodes distributed across 12-, 48-, or 96-well plates, whereas the Maestro Edge accepts a 24-well plate with 384 electrodes.  Both devices utilize a next-generation processor, the BioCore V4, to improve signal acquisition across a wide spectrum of cellular signals, while an integrated environmental chamber maintains the plate at physiological temperature and pH throughout assay read times.  These features are automatically engaged with a “one-touch” setup, whereupon a single button press initiates plate docking, environmental control, and experimental configuration based on recognition of the unique barcode on each MEA plate.

To evaluate the platforms, cardiac and neural cultures were exposed to cardio-active compounds with known arrhythmogenic potential and neuro-active compounds of varying mechanism-of-action, respectively.  All experiments were performed under environmental control (37C, 5% CO2).  Automatic algorithms for arrhythmia detection were used to quantify early-after depolarizations (EADs) for cardio-active compounds.  For both assays, electrical stimulation was used to pace the activity across wells.

The electrophysiological activity was reliable across wells in baseline and in response to addition of the vehicle control due to the stable environmental controls.  The dosing experiments demonstrated reliable and expected responses based on the known mechanisms of action for each compound.  The cardiomyocyte activity was quantified according to the beat period, field potential duration, and presence of EADs, whereas neural activity was quantified by mean firing rate, network burst duration, and synchrony index.  Automated arrhythmia detection matched performance for gold-standard human detection of EADs and metrics quantified on paced activity exhibited improved reliability as compared to spontaneous data.

Joe Maffei

Field Applications Scientist
Axion Biosystems, Inc.
Atlanta, GA

I have previously completed my PhD and now work as a field applications scientist at Axion Biosystems. I support customer applications ranging from disease-in-a-dish modeling to drug safety testing using the Maestro Pro and Maestro Edge multiwell MEA platforms.