Multichannel Systems MEA2100-System Manual - Manual (Page 47)

The MEA2100-System
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Pressure Control via CVP
The pressure control unit CVP (Controlled Vacuum Pump) is a vacuum pump with a pressure
sensor and a waste bottle. A sensor measures the pressure in the compartment attached to the
waste bottle, and can regulate the suction to maintain a constant negative pressure. With this
unit, it is possible to precisely control the suction applied to the slice and to keep the negative
pressure stable during the whole recording period. The accuracy of the pressure control is
0.1 mbar, the maximum negative pressure is 200 mbar below atmospheric pressure. A negative
pressure of 10 to 30 mbar is enough to keep a slice in place on the electrodes. Please read CVP
manual for setting up the vacuum pump. In case of 50 Hz noise, include a metal part in the tubing
to the CVP and ground it to one of the systems ground connectors. It is also recommended to use
a valve between the CVP and the system.
Pressure Control via Syringe
Suction can be applied manually with a syringe. Connect a 1 ml syringe to the tube. After
mounting the slice, gently suck in about 20 to 50 μl with the syringe. It is better not to start with
the syringe at position 0 ml, better have 100 to 200 μl of air already in. Do not apply more suction,
or the slice will be sucked into the holes. Most likely the negative pressure will dissipate over time,
but usually the adhesion of the slice to the pMEA surface is good enough by then to keep it in
place anyway.
Service and Maintenance
You should clean the contact pins of the MEA2100 headstage carefully with a soft tissue and
alcohol or isopropanol from time to time, especially if you have problems with the noise level.
For handling and cleaning of the MEA, please refer to the MEA manual or to MEA Cleaning
Quick Guide on the MCS web site www.multichannelsystems.com.
Warning: Please be very careful when handling the headstage,
or cleaning the device! The pins can be damaged easily.