Multichannel Systems MEA2100-System Manual - Manual (Page 37)

Hardware
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Additionally, the single or double headstages for 60 channels electrodes are also available with
a modified ground plate to accommodate perforated MEAs.
This feature to use perforated MEAs for perfusion from top and suction from the chamber below
the small MEA is also available when using the MEA2100-HS32 or MEA2100-HS2x32 headstages
with one or two MEA with 32 electrodes.
It is possible to connect two headstages to one interface and to control both headstages
independently from each other by opening the data acquisition software MC_Rack twice.
A combination of two different headstages on one interface board is possible. In sum you
can record from up to 240 electrodes.
The amplifiers and data acquisition integrated in the headstage support 120 electrode channels.
The sampling rate, signal range and bandwidth can be adjusted via software control. Thereby
the system is suitable for a broad range of applications, from single unit spike recordings to field
potentials from whole heart preparations.
Electrode raw data acquired from the MEA chip is amplified and digitized by the analog / digital
converter that is integrated in the headstage at sampling rates of up to 50 kHz per channel. Data
is transferred to the interface board via eSATAp cable.
A special advantage are the three integrated stimulus generator units, which deliver monophasic
or biphasic rectangular pulses as single pulse and pulse trains. You can choose between current
or voltage stimulation and you can select each MEA electrode for stimulation within the MC_Rack
software. The integrated blanking circuit (BC) disconnects the electrodes from the amplifiers
during the stimulation and avoids stimulus artifacts.
As usual in MEA-Systems, the MEA2100-System features a heating element with a Pt100
temperature sensor. If you connect a temperature controller TC02 to the heating element via
D-Sub 9 connector, the heating element guarantees constant temperature conditions for the
biological sample on the chip. A perfusion system with heating is available for the MEA2100
as optional accessory.
Because of the compact designed headstage you can use most inverted or upright microscopes,
for the optical control of the sample on the MEA chip.
4.4 Digital Signal Processor
The interface board of the system is equipped with a high-capacity digital signal processor DSP.
The DSP allows online access to the data in real-time. Filtering, spike detection and generation
of feedback stimulation can be controlled via the MC_Rack software. Additionally, the processor
is freely programmable to offer the advanced user more complex online analysis features. It can
be programmed in C using the Code Composer Studio Development Environment from Texas
Instruments. Simlink from Mathworks can also be used to create the model which will run on
the DSP in the MEA2100 interface board.
The DSP has full access to the data stream from all electrodes in real-time and can analyze
the data. It also can access the stimulation unit together with the blanking switches inside
the stimulation unit of the MEA2100. This allows creating closed loop experiments with sub
millisecond delays.
The processed data from the DSP can be streamed to the PC using a dedicated USB connection.
Important: The digital signal processor DSP is not available in MEA2100-32-Systems
and MEA2100-Lite-Systems!