MED64 System

Record high-quality extracellular signals with the industry’s leading low-noise system

MED64 is a user-friendly multi-electrode array (MEA) system for stimulation and recording of field potentials (extracellular signals) from multiple areas within a biological sample over hours, days, weeks and even months. Acute or cultured biological preparations are placed or grown directly on a grid of 64 planar microelectrodes, which serve a dual purpose of stimulus-delivery and signal recording. The unique construction of the system eliminates the need for many cumbersome and expensive equipment used in conventional electrophysiology, including a faraday cage, anti-vibration table, micromanipulators, and even the puller and glass microelectrodes. The MED64 features the industry’s lowest-impedance planar microelectrode, which enables data acquisition with low-noise and superior signal-to-noise ratios.

The MED64 system can be used for diverse research applications involving the central nervous system (CNS), the heart, or any other excitable tissue.


Features

Simultaneous recording of extracellular signals across 64 channels without pulling glass electrodes

• Signals (evoked potentials or spontaneous activity) are acquired with 64 planar microelectrodes patterned on the MED probe.

• Any of the 64 electrodes can be used for stimulation (up to two simultaneously). Stimulus channels and waveforms are selectable by software.


Stable, low-noise, high signal-to-noise ratio recording with 1 µV r.m.s noise level

• The MED64 system’s low-noise level is achieved through the use of the industry’s lowest-impedance electrodes (10kΩ at 1kHz, typically). The MED64 does not require a Faraday cage or vibration-isolation table, and can thus be installed on an ordinary table or lab bench.

• The measured noise level is 1µV r.m.s - lower than any other commercial multi-electrode array system. The superior signal-to-noise-ratio enables acquisition of particularly small signals such as single-unit activities from acute slices (SCN slices).

(25 µV, 100msec/Div)
Micrograph of dissociated neurons cultured on MED probe (top right). Spontaneous neuronal activity displayed at all 64 channels (left) and expanded display of the signal at channel 33 (bottom right).

Effective stimulation and high-quality evoked signals

• Use of the MED64 system for recording electrically evoked signals has been demonstrated in many scientific publications. The planar platinum-black-coated microelectrodes have very high capacitance values (50,000pF for 50 x 50µm microelectrodes), enabling stimulation at high frequencies and large current amplitudes (up to 200µA / 0.2msec).

• Stimulus artifacts are very short in duration, returning to 0µV within 0.5ms at non-stimulated channels. Clean, high-quality evoked potentials can be recorded soon after stimulation.

Mouse hippocampus slice on a MED probe (top-left). Acquired signals at all channels (right), and magnification of the signal at channel 29 (bottom left).

Long-term recording in a humidified incubator

• Dissociated cells and tissue (e.g. slices) can be cultured directly on the MED probe.

• Planar microelectrodes are non-invasive, ideal for maintaining long-term cell and tissue viability.

• The MED probe and connector can be kept in an incubator with 100% humidity, allowing hands-free recording over the course of days, weeks, and months while the sample sits undisturbed in the incubator.


Variety of applications

• The MED64 system is well-suited for acute tissue preparations, as well as cultured tissue or dissociated cells. It is a user-friendly, yet extremely powerful tool for drug testing.

• The low-impedance microelectrodes and wide-bandwidth amplifier enable acquisition of a wide variety of signal types, including slow-wave signals such as fEPSPs, signals from smooth muscle tissue (~ 0.1Hz), as well as high-frequency signals such as neuronal spikes.


On-line analysis with powerful software

• MED64 Mobius software allows MED64 users to analyze signals both on-line (during acquisition) and off-line for all 64 channels.

• The broad set of analysis functions is useful for many different kinds of applications. Components

\