Multichannel Systems MEA User Manual
Microelectrode Array (MEA)
Manual
Information in this document is subject to change without notice.
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of Multi Channel Systems MCS GmbH.
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assume no responsibility for errors or omissions, or for damages resulting from the use of information
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© 2014 Multi Channel Systems MCS GmbH. All rights reserved.
Printed: 08. 05. 2014
Multi Channel Systems
MCS GmbH
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72770 Reutlingen
Germany
Fon +49-71 21-90 92 5 - 0
Fax +49-71 21-90 92 5 -11
info@multichannelsystems.com
www.multichannelsystems.com
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Microelectrode Arrays (MEAs) — Overview
Table of Contents
1 Introduction 6
1.1 About this Manual 6
2 Important Information and Instructions 7
2.1 Operator's Obligations 7
2.2 Guarantee and Liability 7
2.3 Important Safety Advice 8
3 Microelectrode Arrays (MEAs) — Overview 9
3.1 Extracellular Recording with Microelectrode Arrays 9
3.2 MEA Design and Production 10
3.3 Electrodes, Tracks, and Insulation 11
4 MEA Types and Layouts 12
4.1 Standard Electrode Numbering 13
4.2 Standard MEA 14
4.3 High Density MEA: 60HDMEA 15
4.4 Hexa MEA: 60HexaMEA 16
4.5 Thin MEA: 60ThinMEA 17
4.6 Eco MEA: 60EcoMEA 18
4.7 Stimulation MEA: 60StimMEA 19
4.8 Perforated MEA: 60pMEA 20
4.9 Perforated MEAs for Use with MEA2100-32-System
and USB-MEA32-STIM4-System 21
4.10 MEA with 6 Wells: 60-6wellMEA 22
4.11 256MEA for Use with USB-MEA256-System 23
4.12 MEA with 6 Wells for Use with USB-MEA256-System 24
4.13 MEA with 9 Wells for Use with USB-MEA256-System 25
4.14 120MEA with for Use with MEA2100-120-System 26
4.15 Quadrant MEA: 60-4QMEA1000 27
4.16 Square MEA: 60SquareMEA 28
4.17 PEDOT-CNT MEAs: 60PedotMEA 29
4.18 FlexMEA 30
4.19 EcoFlexMEA 32
4.20 MEA Signal Generator: 60MEA-SG 34
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MEA Manual
5
MEA Handling 35
5.1 Hydrophilic Surface Treatment 35
5.1.1 Plasma Cleaning 35
5.1.2 Protein Coating 35
5.1.3 Preculturing 36
5.2 Sterilization 36
5.2.1 Sterilization with Ethanol and UV Light 36
5.2.2 Steam Sterilization (Autoclavation) 36
5.2.3 Dry-Heat Sterilization 36
5.2.4 Sterilization with Hot Water 36
5.3 MEA Storage 37
5.4 MEA Coating 37
5.4.1 Coating with Nitrocellulose 37
5.4.2 Coating with Polyethyleneimine (PEI) plus Laminin 38
5.4.3 Coating with Polyornithine (plus Laminin) 39
5.4.4 Coating with Poly-D-Lysine (plus Laminin) 40
5.4.5 Coating with Poly-D-Lysine (plus Fibronectin) 41
5.4.6 Coating with Fibronectin 41
5.4.7 Coating with Collagen 42
5.5 Cleaning of used MEAs 43
5.5.1 General Recommendations for Cleaning MEAs 43
5.5.2 Cleaning of pMEAs 43
5.5.3 Cleaning of EcoMEAs 43
5.5.4 Cleaning of EcoFlexMEAs 43
5.5.5 Cleaning of FlexMEAs 44
5.5.6 Removing Nitrocellulose Coating 44
5.5.7 MEA Cleaning with EDTA-Collagenase 44
5.5.8 MEA Cleaning with Terg-A-Zyme 45
4
6 Culture Chamber Options 47
6.1 MEA2100-CO2-C 47
6.2 Sealed MEA Culture Dish 47
6.3 MEA Culture Chamber with Lid 48
6.4 Culture Chamber for 9-Well MEAs 48
6.5 Culture Chamber for 6-Well MEAs 48
Microelectrode Arrays (MEAs) — Overview
7
Recording with MEAs 50
7.1 Mounting the MEA 50
7.1.1 Cleaning the Contact Pads 50
7.1.2 Positioning the MEA 50
7.1.3 Grounding the Bath 50
7.2 General Performance / Noise Level 51
8
Stimulation 53
8.1 Using MEA Electrodes for Stimulation 53
8.2 Capacitive Behavior of Stimulating Electrodes 54
8.3 Aspects of Electrode Size and Material 55
8.4 Recommended Stimulus Amplitudes and Durations 56
9 Troubleshooting 57
9.1 About Troubleshooting 57
9.2 Technical Support 57
9.3 Noise on Single Electrodes 58
9.4 Overall Noise / Unsteady Baseline 60
9.5 Missing Spikes or Strange Signal Behavior 61
10 Appendix 63
10.1 Contact Information 63
10.2 Safe Charge Injection Limits 64
10.3 Data Sheets 65
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MEA Manual
1 Introduction
1.1 About this Manual
The MEA manual comprises all important information about the microelectrode arrays (MEA) for use with
(USB-) MEA- or ME-Systems from Multi Channel Systems. The MEA manual focuses on general information
on the MEA design, use, and handling, and more specific information on different MEA types. It also
includes recommendations on sterilization, coating, and cleaning procedures, from scientifical papers
or from recommendations of other MEA users.
For more details on issues that refer to the amplifier, like grounding or mounting the MEA, please refer to
the manual for the MEA amplifier you use. You will find more information about the MEA-System and its
components in general, especially the data acquisition card, in the MEA-System manual. For more details
on the data acquisition and analysis program MC_Rack, please refer to the MC_Rack manual.
It is assumed that you have already a basic understanding of technical terms. No special skills are required
to read this manual.
The components and also the manual are part of an ongoing developmental process. Please understand
that the provided documentation is not always up to date. Please check the MCS Web site
(www.multichannelsystems.com) from time to time for downloading up-to-date manuals.
Those parts in this manual that refer to the applications, and not to the product itself, for example,
coating of MEAs, are only a summary of published information from other sources (see references) and
has the intention of helping users finding the appropriate information for setting up their experiments.
Multi Channel Systems MCS GmbH has not tested or verified this information. Multi Channel Systems MCS
GmbH does not guarantee that the information is correct. Multi Channel Systems MCS GmbH recommends
to refer to the referenced literature for planning and executing any experiments.
6
Microelectrode Arrays (MEAs) — Overview
2 Important Information and Instructions
2.1 Operator's Obligations
The operator is obliged to allow only persons to work on the device, who
are familiar with the safety at work and accident prevention regulations and have been instructed
how to use the device;
are professionally qualified or have specialist knowledge and training and have received instruction
in the use of the device;
have read and understood the chapter on safety and the warning instructions in this manual
and confirmed this with their signature.
It must be monitored at regular intervals that the operating personnel are working safely.
Personnel still undergoing training may only work on the device under the supervision
of an experienced person.
2.2 Guarantee and Liability
The General conditions of sale and delivery of Multi Channel Systems MCS GmbH always apply.
The operator will receive these no later than on conclusion of the contract.
Multi Channel Systems MCS GmbH makes no Guarantee as to the accuracy of any and all tests and data
generated by the use of the device or the software. It is up to the user to use good laboratory practice to
establish the validity of his findings.
Guarantee and liability claims in the event of injury or material damage are excluded when they are the
result of one of the following.
Improper use of the device.
Improper installation, commissioning, operation or maintenance of the device.
Operating the device when the safety and protective devices are defective and/or inoperable.
Non-observance of the instructions in the manual with regard to transport, storage, installation,
commissioning, operation or maintenance of the device.
Unauthorized structural alterations to the device.
Unauthorized modifications to the system settings.
Inadequate monitoring of device components subject to wear.
Improperly executed and unauthorized repairs.
Unauthorized opening of the device or its components.
Catastrophic events due to the effect of foreign bodies or acts of God.
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MEA Manual
2.3 Important Safety Advice
Warning: Make sure to read the following advice prior to install or to use the device and the software.
If you do not fulfill all requirements stated below, this may lead to malfunctions or breakage of
connected hardware, or even fatal injuries.
Warning: Obey always the rules of local regulations and laws. Only qualified personnel should be
allowed to perform laboratory work. Work according to good laboratory practice to obtain best results
and to minimize risks.
The product has been built to the state of the art and in accordance with recognized safety engineering
rules. The device may only
be used for its intended purpose;
be used when in a perfect condition.
Improper use could lead to serious, even fatal injuries to the user or third parties and damage to the device
itself or other material damage.
Warning: The device and the software are not
humans.
Malfunctions which could impair safety should be rectified immediately.
Regard the technical specifications of the various MEA types, especially the temperature range and the safe
charge injection limits for stimulation.
Do not autoclave or expose pMEAs to heat more than 50 °C.
Do not touch the electrode field in any way.
Do not use any liquids or cleaning solutions with a high pH (> 7) for a longer period of time on MEAs
of a silicon nitride insulation type. Basic solutions will damage TiN electrodes.
intended for medical uses and must not be used on
8
3 Microelectrode Arrays (MEAs) — Overview
3.1 Extracellular Recording with Microelectrode Arrays
A microelectrode array (MEA) is an arrangement of typically 60 electrodes allowing the targeting of several
sites in parallel for extracellular recording and stimulation.
Cell lines or primary cell preparations are cultivated directly on the MEA. Freshly prepared slices can be used
for acute recordings, or can be cultivated as organotypic cultures (OTC) on the MEA.
Recorded signals are amplified by a filter amplifier and sent to the data acquisition computer. All MEAs
(except EcoFlex- or FlexMEAs) are only for use with MEA-Systems or USB-MEA-Systems for extracellular
recording from Multi Channel Systems MCS GmbH. FlexMEAs may be used with components of
ME-Systems and USB-ME-Systems from Multi Channel Systems MCS GmbH. EcoFlex- and FlexMEAs are
designed for use in in vitro or in vivo studies. Please see setup manuals “Setup (USB-) MEA-Systems and
(USB-) ME-Systems” for more information.
Several MEA geometries are provided for a wide variety of applications. Almost all excitable or electrogenic
cells and tissues can be used for extracellular recording in vitro, for example, central or peripheral neurons,
cardiac myocytes, whole-heart preparations, or retina.
MEA Manual
There are various applications for MEAs in the fields of neurobiology and cardiac electrophysiology.
Typical neurobiological applications are: Ion channel screening, drug testing, safety pharmacology studies,
current source density analysis, paired-pulse facilitation (PPF), long term potentiation (LTP) and depression
(LTD), I / O relationship of evoked responses, circadian rhythm, neuroregeneration, developmental biology,
microencephalograms (EEG), and microelectroretinograms (ERG).
Typical applications in the cardiac field are: Activation and excitation mapping, measuring of the conduction
velocity, longterm characterizations of cell types (especially stem cells), culture pacing, drug testing, safety
pharmacology studies, monitoring of QT-related prolongation and arrhythmias, cocultures and disease /
implantation model.
For more information on published applications or procedures for biological preparations, please see the
application notes on the MCS web site:
http://www.multichannelsystems.com/applications.html
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MEA Manual
3.2 MEA Design and Production
A standard MEA biosensor has a square recording area of 700 μm to 5 mm length. In this area,
60 electrodes are aligned in an 8 x 8 grid with interelectrode distances of 100, 200, or 500 μm. Planar
TiN (titanium nitride) electrodes are available in sizes of 10, 20, and 30 μm, and three-dimensional TiN
electrodes have a diameter of > 20 μm at the base with a very fine tip. Standard MEAs are useful for
a wide variety of applications. Different geometries match the anatomical properties of the preparation.
Most MEAs are available with a substrate-integrated reference electrode replacing the silver pellet in the
bath. All electrodes can either be used for recording or for stimulation.
In principle MEA electrodes are not arranged symmetrical, so the MEA chip has to be placed inside the
amplifier in the recommended manner.
Several other MEA types and layouts that are dedicated to special applications are also available, please
see chapter “MEA Types and Layouts” for more details.
The biological sample can be positioned directly on the recording area; the MEA serves as a culture and
perfusion chamber. A temperature controller controls the temperature in the culture chamber. Various
culture chambers are available, for example, with leak proof lid or with semipermeable seal. An incubator
is not necessarily required, long-term recordings in the MEA culture chamber are possible over several
weeks or even months.
For cell or slice cultures, MEAs have to be coated with standard procedures before use to improve the cell
attachment and growth, please read chapter “MEA Coating”.
Spike activity can be detected at distances of up to 100 μm from a neuron in an acute brain slice. Typically,
signal sources are within a radius of 30 μm around the electrode center. The smaller the distance, the
higher are the extracellular signals. The higher the spatial resolution, the lower the numbers of units that
are picked up by a single electrode, that is, the less effort has to be put into the spike sorting.
Multi Channel Systems provides MEAs with the highest spatial resolution in the market. HighDenseMEAs
have electrodes with a diameter of only 10 μm arranged in a distance of only 30 μm (center to center).
The challenge of manufacturing very small electrodes and at the same time keeping the impedance and
the noise level down has been met by introducing a new electrode material: Titanium nitride (TiN).
The NMI in Reutlingen, Germany (www.nmi.de), produces MEAs from very pure fine quality and highly
biocompatible materials. The NMI is a research institute, with which Multi Channel Systems has
collaborated in many projects and over many years.
Quality controls and production processes have been improved over the last years so that MEAs are always
of a fine consistent quality at very reasonable prices.
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3.3 Electrodes, Tracks, and Insulation
Microfold structures result in a large surface area that allows the formation of electrodes with an excellent
signal to noise ratio without compromising on the spatial resolution.
TiN (titanium nitride) is a very stable material that, for example, is also widely used for coating heavy
equipment. All MEAs with TiN electrodes have a long life and can be reused several times if handled with
care. If used for acute slices, MEAs can be used for approximately one year. Additionally available are
EcoMEAs equipped with gold (Au) electrodes.
Long-time experiments with cell cultures and rigid cleaning methods shorten the MEA lifetime, but you
can still reuse a MEA about 30 times, depending on the coating, cell culture, and cleaning procedure.
All MEAs (except pMEAs) show excellent temperature compatibility and are stable from 0 °C to 125 °C,
that is, they can be autoclaved.
The impedance of a flat, round titanium nitride (TiN) electrode ranges between 30 and 400 kiloohms,
depending on the diameter. The smaller an electrode, the higher is the impedance. On one hand, lower
impedance seems desirable, but on the other hand, a smaller electrode and interelectrode distance results
in a higher spatial resolution.
Multi Channel Systems provides MEAs with TiN electrodes with sizes of 10, 20, or 30 μm and gold
electrodes with 100 μm, which all show an excellent performance and low noise level. The average
noise level of 30 μm and 10 μm electrodes is less than 10 μV and 15 μV peak to peak, respectively.
MEA Manual
Gold electrodes (EcoMEAs) are only available with a low spatial resolution and are useful for medium
throughput screening, where costs are a limiting factor.
All planar TiN electrodes are positioned on a round pad with a diameter of 40 μm. If you like to check
the electrodes with a light microscope, you will need an upright microscope to see the MEA from above.
With an inverse microscope, you are only able to see the (bigger) pad from below, not the electrode itself.
The electrodes are embedded in a carrier material, usually glass. Standard tracks made of titanium (Ti)
or indium tin oxide (ITO) are electrically isolated with silicon nitride (SiN). Standard contact pads are made
of titanium nitride (TiN) or indium tin oxide (ITO). ITO contact pads and tracks are transparent, for a perfect
view of the specimen under the microscope.
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MEA Manual
4 MEA Types and Layouts
Various types of MEA biosensors are available for all kind of extracellular multi channel recordings.
Typical MEAs for in vitro applications have 60 microelectrodes arranged in an 8 x 8 layout grid embedded
in a transparent glass substrate. You can cultivate the tissue or cell culture directly on the MEA. EcoFlexand FlexMEAs are made for in vivo and in vitro applications.
MEA types differ in the materials used for the carrier and the recording area, and in the geometry, that is,
electrode size and interelectrode distances. The electrode size and interelectrode distances are used for
categorizing MEAs: The first number refers to the interelectrode distance, for example 200 μm, and the
second number refers to the electrode size, for example 10 μm, which results in the standard MEA type
200/10, for example.
Standard versions are available with an internal reference electrode (abbreviated “iR”) and with various
culture chamber interface options. Culture chambers are available with and without lid.
Please ask for custom layouts, that is, MEA layouts according to your specifications.
In this chapter, each MEA type is briefly described and noted.
Standard MEAs with flat round TiN electrodes in an 8 x 8 layout grid for all applications.
MEAs with 6 x 10 layout grid and 500 μm inter electrode distances.
HighDenseMEAs with the highest spatial resolution and a double recording field of 5 x 6 electrodes each.
HexaMEAs featuring a hexagonal layout, perfect for recording from retina.
ThinMEAs with a "thickness" of only 180 μm, ideally suited for high-resolution imaging.
Very cost efficient and robust EcoMEAs on glass or PCB (printed circuit board) base for applications with
lower spatial resolution and higher throughput, especially for established cardiomyocyte cultures, large
slices, or whole-heart preparations.
Stimulation MEAs with 16 additional stimulation electrodes.
Perforated MEAs allow perfusing the acute slice from up- and downside. For use with MEA2100
headstages equipped with perfusion element (MEA2100-PE) and MEA1060 amplifiers with perfusion
ground plate (MEA-PGP) or with.
Small perforated MEAs with 32 recording and 12 stimulation electrodes specified for use with
MEA2100-32- and USB-MEA32-STIM4-System.
6 well MEAs feature a round MEA layout, separated in six segments of 3 x 3 electrodes, like a pie-chart.
Using the 6 well MEA with macrolon triangle or round chamber ring, you have 6 separate culture chambers
on one MEA, for example, for drug application in a screening experiment.
4 quadrant 1000 MEAs with electrode layout organized in four quadrants and a center line.
256MEAs with 252 recording electrodes in a 16 x 16 layout grid for use with USB-MEA256-System.
6 well MEAs for use with USB-MEA256-System. 252 electrodes in 6 blocks of 6 x 7 electrodes in a round
layout for use with 6 well macrolon triangle or round chamber rings. You have 6 separate culture chambers
on one MEA, for example, for drug application in a screening experiment.
9 well MEAs for use with USB-MEA256-System. 256 electrodes in nine blocks of 26 recording, two
stimulation and reference electrodes each. Using the 9 well MEA with macrolon quadrant, you have
9 separate culture chambers, for example, for drug application in a screening experiment.
120MEAs and a perforated 120pMEA with 12 x 12 layout grid for use with MEA2100-120-System only.
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MEA Manual
Square MEAs with TiN (Titanium nitride) electrodes in 50 x 50 μm square size in a 8 x 8 layout grid.
PEDOT-CNT MEAs with carbon nanotube – poly 3,4-ethylene-dioxythiophene electrodes and gold tracks
and contact pads have very low impedance values of approximately 20 kThey are ideal for stimulation
and have excellent biocompatibility and cell adhesion.
FlexMEAs made of flexible polyimide 2611 foil, perfect for in vivo and specific in vitro applications, for
example, whole-heart preparations. Available with 36 (FlexMEA36) or 72 (FlexMEA72) TiN (Titanium nitride)
electrodes.
EcoFlexMEAs made of flexible polyimide (Kapton) as well, but very cost efficient and more robust than
FlexMEAs from polyimide foil. Available with 36 (EcoFlexMEA36) or 24 (EcoFlex24) gold electrodes.
4.1 Standard Electrode Numbering
The numbering of MEA electrodes in the 8 x 8 grid (standard MEAs, ThinMEAs, EcoMEAs, StimMEAs,
pMEAs) follows the standard numbering scheme for square grids: The first digit is the column number,
and the second digit is the row number. For example, electrode 23 is positioned in the third row of the
second column.
These numbers are the same numbers that are used as channel numbers in the MCS data acquisition
software, for example the MC_Rack program. Using MC_Rack please make sure that you have selected
the two-dimensional MEA layout as the “Channel Layout” in “Data Source Setup”. For more details,
please refer to the MC_Rack manual or help.
Important: MEAs are not symmetrical! That is, why the writing (for example NMI, LEITER, MEA type) on
the MEA chip should be on the right side viewed from the front, with the sockets of the amplifier in the
back. MEAs with one big internal reference electrode should be placed with reference electrode to the left
side in the amplifier. Otherwise, the MEA layout will not match with the pin layout of the channel map in
MC_Rack.
Other electrode grids are described in the next chapter, and in the Appendix.
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MEA Manual
4.2 Standard MEA
60MEA100/10-ITO, 60MEA200/10iR-ITO, 60MEA200/30iR-ITO, 60MEA100/10iR-TI, 60MEA200/10-Ti,
60MEA200/30-Ti, 60MEA200/10iR-TI, 60MEA200/30iR-Ti,60MEA500/10iR-Ti, 60MEA500/30iR-Ti
Standard MEAs have 60 electrodes in an 8 x 8 layout grid with electrode diameters of 10 μm or 30 μm,
and interelectrode distances of 100 μm, 200 μm. The MEAs with an interelectrode distance of 500 μm
have a 6 x 10 layout grid.
Versions 200/10, 200/30, 100/10 are available without or with an internal reference electrode as indicated
by the abbreviation iR. You can connect the internal reference electrode directly to the amplifier's ground
and will not need silver pellets for grounding the bath anymore. Please refer to the MEA manual delivered
with your MEA amplifier for more information.
The flat, round electrodes are made of titanium nitride (TiN). MEAs with TiN electrodes are very stable.
Therefore, the MEAs can be reused several times and are perfect for long-time experiments (up to several
weeks and even months). The electrode impedance ranges between 30 k and 400 k depending on the
electrode diameter. Generally, the smaller the electrode, the higher is the impedance.
Tracks are made of titanium (Ti) and contact pads are made of titanium nitride (TiN) or indium tin oxide
(ITO); insulation material is silicon nitride. ITO contact pads and tracks are transparent, for a perfect view
of the specimen under the microscope.
Important: MEAs are not symmetrical! That is, why the writing (for example NMI, LEITER, MEA type) on
the MEA chip should be on the right side viewed from the front, with the sockets of the amplifier in the
back. MEAs with one big internal reference electrode should be placed with reference electrode to the left
side in the amplifier. Otherwise, the MEA layout will not match with the pin layout of the channel map in
MC_Rack.
Using standard MEAs
Standard MEAs can be used for a wide variety of applications. They are robust and heat-stabilized. They can
be autoclaved and coated with different procedures for cell and tissue cultures. Generally, they can be used
for acute experiments as well as long-term cultures.
14
4.3 High Density MEA: 60HDMEA
60HDMEA30/10iR-ITO
MEA Manual
10 μm electrodes are arranged in two recording fields with 5 x 6 electrodes each. The interelectrode
spacing is only 30 μm center to center.
The very high electrode density of the two recording fields on a 60HDMEA is only possible by the special
TiN electrode material and production process. This MEA type is especially useful for applications, where
a high spatial resolution is critical, for example, for multitrode analysis.
For example, the very high spatial resolution of the high density MEAs is very useful for recording from
retina ganglia cells. The double recording field can also be used for coculturing two slices, each on one
recording field. The flat, round electrodes are made of titanium nitride (TiN).Tracks and contact pads are
made of transparent indium tin oxide (ITO); insulation material is silicon nitride.
60HDMEA30/10iR-ITO MEAs are available with internal reference electrode.
Using 60HDMEAs
The same material is used for standard MEAs and high density MEAs. Therefore, they are equally robust
and heat-stabilized. They can be autoclaved and coated with different procedures for cell and tissue
cultures.
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MEA Manual
4.4 Hexa MEA: 60HexaMEA
60HexaMEA-Ti, 60HexaMEA-ITO, 60HexaMEA40/10iR-ITO
Electrode layout for 60HexaMEA-Ti and 60HexaMEA-ITO.
Electrode layout for 60HexaMEA40/10iR-ITO.
HexaMEAs feature a hexagonal layout, perfect for recording from retina.
The 60 electrodes of 60HexaMEA-Ti or 60HexaMEA-ITO are aligned in a special configuration with varying
electrode diameters (10, 20, 30 μm) and interelectrode distances (see upper pictures).The specific layout
resembles ideally the regularity of the retina's architecture. The density of neurons is more important in the
center than in the peripheral. This is matched by the density of electrodes on the MEA, which is also higher
in the center than in the peripheral.
The flat, round electrodes are made of titanium nitride (TiN).
Tracks are made of opaque Ti or transparent ITO, and contact pads are made of TiN or ITO.
The insulation material is silicon nitride.
Electrodes in the center have a diameter of 10 μm with an interelectrode distance of 20 μm, where
the peripheral electrodes have a diameter of 20 μm and 30 μm. This type of HexaMEA (60HexaMEA-Ti,
60HexaMEA-ITO ) provides no internal reference electrode.
The electrodes of 60HexaMEA40/10iR-ITO are configured with invariable interelectrode distance of 40 μm,
and with TiN electrodes of 10 μm diameter. They include a big internal reference electrode. The tracks and
contact pads are made of ITO.
Using 60HexaMEAs
The same material is used for standard MEAs and HexaMEAs. Therefore, they are equally robust and heatstabilized. They can be autoclaved and coated with different procedures for cell and tissue cultures.
16
4.5 Thin MEA: 60ThinMEA
60ThinMEA200/30iR-ITO, 60ThinMEA30/10iR-ITO
MEA Manual
60ThinMEAs are only 180 μm "thick", ideally suited for high-resolution imaging. 60ThinMEAs are like
standard MEAs, but the electrodes are embedded in a very thin and delicate glass substrate on a robust
ceramic carrier. The thin glass allows the use of oil immersion objectives with a high numerical aperture.
Like standard MEAs, 59 electrodes and one reference electrode are arranged in an 8 x 8 layout grid with
electrode diameters of 30 μm and interelectrode distances of 200 μm.
60ThinMEAs are also available in a double 5 x 6 layout grid with 10 μm TiN electrodes and 30 μm
interelectrode distance like the High Dense MEA (60ThinMEA30/10iR-ITO).
The flat, round electrodes are made of titanium nitride (TiN).
Tracks and contact pads are made of transparent ITO; insulation material is silicon nitride.
Using 60ThinMEAs
60ThinMEAs are heat-stabilized and can be autoclaved. They can also be coated with different procedures
for cell and tissue cultures.
They should be handled with great care because of the thin and delicate recording area.
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MEA Manual
4.6 Eco MEA: 60EcoMEA
60EcoMEA, 60EcoMEA-Glass
60EcoMEAs are available on opaque printed circuit board (PCB) and on transparent glass base (60EcoMEAGlass). They are low price variants for medium throughput applications like small screens where material
costs play a bigger role than in more scientific MEA applications.
60EcoMEAs are opaque and are therefore useful only for applications where you do not need a visual
control under a microscope, for example, for established cell cultures. 60EcoMEA-Glasses are transparent
all-purpose MEAs.
Due to the special production process on PCB, electrodes of 60EcoMEAs are available only with a diameter
of 100 μm and an interelectrode distance of 700 μm. The electrodes on 60EcoMEA-Glass also have
a diameter of 100 μm and a distance of 700 μm. Thus, 60EcoMEA or 60EcoMEA-Glass are useful for
applications where a high spatial resolution is not important, but which emphasize on low price
consumables. They have proven to be especially useful for recordings from established cardiomyocyte
cultures. They are not useful for establishing a new cell culture, as the cell performance cannot be
monitored. Multi Channel Systems recommends to use standard 200/30 MEAs for establishing the cell
culture first, then switch to 60EcoMEA or 60EcoMEA-Glass.
60EcoMEAs are provided in the typical 8 x 8 layout with internal reference electrode. Custom layouts
following your personal specifications are possible at very reasonable prices. Please ask your local retailer
for details. Electrodes, tracks, and contact pads are made of pure gold. Due to the soft gold material of the
contact pads, the contact to the amplifier pins is excellent. The insulation material on EcoMEA-Glass chips
is SU-8 (a photoresist, 1 - 2 μm)
Using 60EcoMEAs
Like standard MEAs, 60EcoMEAs are very robust and heat-stabilized. They can be autoclaved and coated
with different procedures for cell and tissue cultures. The gold electrodes are very robust, too, and are the
only MEA electrodes that will endure more severe cleaning methods.
New 60EcoMEAs are very hydrophobic. They should be coated with nitrocellulose or treated with a plasma
cleaner before use.
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4.7 Stimulation MEA: 60StimMEA
60StimMEA200/30-Ti
MEA Manual
Stimulation MEAs are available in 8 x 8 standard MEA layout with additional 16 stimulation electrodes.
Eight pairs of the stimulation electrodes are big and square, the other eight pairs have the same size as
the recording electrodes (30 μm). For perfect use with the MEA1060 amplifiers is it necessary to connect
adapters: MEA-STIM-ADPT-INV-BC for MEA1060-Inv-BC amplifiers, MEA-STIM-ADPT-Up(BC) for MEA1060Up(BC) amplifiers.
Stimulation MEAs are useful, for example, for pacing cardiac tissues like hESCM (human embryonic stem
cells derived cardiac myocytes), that need higher voltages and durations than stimulation of neuronal
tissues. So, the use of larger stimulating electrodes is recommended.
Using 60StimMEAs
The same material is used for standard MEAs and 60StimMEAs. Therefore, they are equally robust and
heat-stabilized. They can be autoclaved and coated with different procedures for cell and tissue cultures.
19
MEA Manual
4.8 Perforated MEA: 60pMEA
60pMEA200/30iR-Ti 60pMEA100/30iR-Ti
Acute slice recordings on common glass MEAs are done from the cells at the bottom of the slice, which are
in contact with the MEA electrodes. These cells get less oxygen and nutrients from the perfusion medium,
and therefore are likely to give smaller signals and might eventually die first. Perforated MEAs present a
solution to this problem as they allow a perfusion of the tissue from both sides at the same time, thereby
optimizing the oxygen supply of the acute slice.
Perforated MEAs are identical in size and function to the regular MEAs. The recording electrodes are
arranged in 8 x 8 standard layout grid in 60pMEA200/30iR-Ti, and in 6 x 10 layout grid in
60pMEA100/30iR-Ti. The electrodes are integrated into a thin polyimide foil. This thin foil is fixed on
a ceramic or glass waver for mechanical stability. In the middle of the waver, under the electrode field,
there is a hole that makes it possible to access the electrode field from below. The area around the
electrodes is perforated to allow a perfusion of the tissue from both sides. The total area of the holes
averages 0.8 mm, the diameters of the holes varies between 20 μm and 90 μm.
These pMEAs are designed for use with MEA2100-System headstages with perfusion element (PE) and
MEA1060 amplifier equipped with a perfusion ground plate (PGP). The PE or PGP replaces the standard
ground plate of the headstage or MEA1060 amplifier. Please note that there are different types of the
MEA-PGPs for different amplifier types (MEA1060-UP-PGP, MEA1060-UP-BC-PGP, and MEA1060-INV /
INV-BC-PGP). Additional to the use of 60pMEAs together with the MEA2100-(2x)60-System, you can use
120pMEAs with MEA2100-120-System equipped with a perfusion element (PE) integrated in the ground
plate of the headstage.
For an overview of suggested configurations to work with 60pMEAs, see the MEA Application Note
“Acute Hippocampal Slices on pMEAs”.
Using 60pMEAs
Perforated MEAs have a robust ceramic carrier or they are mounted on glass as usual, but the electrodes
are embedded in polyimide foil. Therefore they are heat stable to 50 °C only, and cannot be autoclaved.
Please do not use an ultrasonic bath for cleaning.
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4.9 Perforated MEAs for Use with MEA2100-32-System
and USB-MEA32-STIM4-System
pMEA-32S12-L1, pMEA-32S12-L2, pMEA-32S12-L3, pMEA-32S12-L4
pMEA-32S12-Lx
For the USB-MEA32-STIM4-System small perforated MEAs have been designed. Please see USB-MEA32STIM4 manual for detailed information. Additionally the MEA2100-32-System is adapted for these small
type of MEA. The pMEAs are different in size, but identical in function to the regular pMEAs. Layout 1
(pMEA-32S12-L1) of the perforated MEAs designed for the MEA2100-32- and for the USB-MEA32-
STIM4-System has been optimized for acute hippocampal slices.
MEA Manual
The flat, round electrodes are made of titanium nitride (TiN) with a diameter of 30 μm for the recording
electrodes, and 50 μm for the stimulation electrodes. The stimulation electrodes can not be used for
recording, and vice versa. The interelectrode distances vary from 150 to 200 μm. MEAs with titanium
nitride (TiN) electrodes are very stable. Therefore, the pMEA can be reused several times and is perfect for
long-time experiments (up to several weeks and even months). The electrode impedance ranges between
30 k and 50 k. Tracks and contact pads are made of titanium nitride (TiN), the insulation material is
polyimide, respectively.
The electrodes are integrated into a thin polyimide foil. This thin foil is fixed on a ceramic waver for
mechanical stability. In the middle of the waver, under the electrode field, there is a hole that makes it
possible to access the electrode field from below. The area around the electrodes is perforated to apply
suction to the slice from below. The total area of the holes averages 0.8 mm, the diameters of the holes
varies from 20 to 90 μm. Please read chapter "Working with the USB-MEA32-STIM4 Amplifier"
in USB-MEA32-STIM4 manual or “Setting up the MEA” in the MEA2100 manual.
Using pMEAs
Perforated MEAs have a robust ceramic carrier, but the electrodes are embedded in polyimide foil.
Therefore they are heat stable to 50 °C only, and cannot be autoclaved. Please do not use an ultrasonic
bath for cleaning.
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MEA Manual
4.10 MEA with 6 Wells: 60-6wellMEA
60-6wellMEA200/30iR-Ti
60-6wellMEAs are MEA chips with six independent culture chambers, separated by a macrolon ring. Inside
each well, in between the marked two bars coming out of the circle in the middle of the MEA, there is a
field of nine electrodes with an internal reference electrode. The electrode in the center of the MEA is for
grounding.
60-6wellMEAs are developed, for example, for safety-pharmacological screenings of drug induced
QT-prolongation. Multi Channel System MCS GmbH provides a software solution for these experimental
intentions, the QT-Screen-Lite program. The 60-6wellMEA allows running six experiments with identical
surrounding conditions at once. Two types of macrolon rings are available: Rings with six triangular
chambers and rings with round chambers.
The electrodes of the 60-6wellMEA are from titanium nitride (TiN), the isolation is made up of Silicon nitride
(SiN). Contact pads are from titanium nitride (TiN), and tracks are from titanium (Ti). The diameter of the
electrodes is 30 μm, the distance from centre to centre is 200 μm.
Using 60-6wellMEAs
60-6wellMEAs can be used for a wide variety of applications. They are robust and heat-stabilized. They can
be autoclaved and coated with different procedures for cell and tissue cultures. Generally, they can be used
for acute experiments as well as long-term cultures.
22
4.11 256MEA for Use with USB-MEA256-System
256MEA30/8-ITO, 256MEA60/10iR-ITO, 256MEA100/30-ITO, 256MEA200/30-ITO, and 256ThinMEA
The 256MEAs have to be used with the USB-MEA256-System.
Please refer to the USB-MEA256-System manual for detailed information.
The 256MEA contains 252 recording, and four ground electrodes arranged in a 16 x 16 layout grid
embedded in a transparent glass substrate. The contact to the amplifier is provided by a double ring of
contact pads around the rim of the MEA. The standard material for MEAs is also used for 256MEAs: The
electrodes are from titanium nitride (TiN) with a silicon nitride (SiN) isolator, and contact pads and tracks
are made of transparent indium tin oxide (ITO).
The spacing of the electrodes in the 16 x16 grid averages 30, 60, 100 μm or 200 μm between the
electrodes. The electrode diameter of 30 μm results in an impedance of approximately 30 - 50 k. The
electrode diameter of 10 μm results in an impedance of approximately 250 - 400 k. The dimension of the
glass carrier is 49 x 49 x 1 mm as usual. 256MEAs are stable in a temperature range from 0 ° - 125 °C.
The 256MEA is only MEA type, which is rotationally symmetric.
256ThinMEAs are only 180 μm "thick", ideally suited for high-resolution imaging. 256ThinMEAs are like
standard MEAs, but the electrodes are embedded in a very thin and delicate glass substrate on a robust
ceramic carrier. The thin glass allows the use of oil immersion objectives with a high numerical aperture.
MEA Manual
Like 256MEAs, 252 electrodes are arranged in a 16 x 16 layout grid with electrode diameter of 30 μm,
and interelectrode distance of 200 μm (256ThinMEA200/30-ITO).
Using 256MEAs
The same material is used for standard MEAs and 256MEAs. Therefore, they are equally robust and heatstabilized. They can be autoclaved and coated with different procedures for cell and tissue cultures.
Using 256ThinMEAs
256ThinMEAs are heat-stabilized and can be autoclaved. They can also be coated with different procedures
for cell and tissue cultures. They should be handled with great care because of the thin and delicate
recording area.
23
MEA Manual
4.12 MEA with 6 Wells for Use with USB-MEA256-System
256-6wellMEA200/30iR-Ti
The 256-6wellMEA200/30iR-ITO has 256 electrodes and has to be used with the USB-MEA256-System.
Please refer to the USB-MEA256-System manual for detailed information.
The dimension of the glass carrier is 49 x 49 x 1 mm as usual. The MEAs with 6 wells are stable
in a temperature range from 0 ° - 125 °C.
The 256-6wellMEA contains 252 recording, 6 reference and four ground electrodes arranged in 6 electrode
blocks with a 6 x 7 layout grid for the recording electrodes. The reference electrode is around each block.
They are embedded in a transparent glass substrate. The contact to the amplifier is provided by a double
ring of contact pads around the rim of the MEA. The standard material for MEAs is also used for
256-6wellMEA: The electrodes are from titanium nitride (TiN) with a silicon nitride (SiN) isolator,
and contact pads and tracks are made of transparent indium tin oxide (ITO).
Using the 256-6wellMEA with macrolon ring, you have six separate culture chambers on one MEA,
for example, for drug application in a screening experiment.
The spacing between the recording electrodes in the 6 x 7 grid averages 200 μm between the electrodes.
The electrode diameter of 30 μm results in an impedance of approximately 30 - 50 k.
Using 256-6wellMEAs
The same material is used for standard MEAs and 256-6wellMEAs. Therefore, they are equally robust and
heat-stabilized. They can be autoclaved and coated with different procedures for cell and tissue cultures.
24
4.13 MEA with 9 Wells for Use with USB-MEA256-System
256-9wellMEA300/30iR-ITO
MEA Manual
The 256-9wellMEA300/30iR-ITO has 256 electrodes and has to be used with the USB-MEA256-System.
Please refer to the USB-MEA256-System manual for detailed information.
The dimension of the glass carrier is 49 x 49 x 1 mm as usual. The MEAs with 9 wells are stable
in a temperature range from 0 ° - 125 °C.
The 256-9wellMEA contains 234 recording, 18 stimulation or recording, and four ground electrodes
arranged in nine electrode blocks with a 6 x 5 layout grid for the recording electrodes, two stimulation
or recording electrodes, and one reference electrode per each block. They are embedded in a transparent
glass substrate. The contact to the amplifier is provided by a double ring of contact pads around the rim of
the MEA. The standard material for MEAs is also used for 256-9wellMEA: The electrodes are from titanium
nitride (TiN) with a silicon nitride (SiN) isolator, and contact pads and tracks are made of transparent indium
tin oxide (ITO).
Using the 256-9wellMEA with macrolon quadrate, you have nine separate culture chambers on one MEA,
for example, for drug application in a screening experiment.
The spacing between the recording electrodes in the 6 x 5 grid averages 300 μm between the electrodes.
The electrode diameter of 30 μm results in an impedance of approximately 30 - 50 k. The dimension of
the square stimulation electrode is 50 x 200 μm.
Using 256-9wellMEAs
The same material is used for standard MEAs and 256-9wellMEAs. Therefore, they are equally robust and
heat-stabilized. They can be autoclaved and coated with different procedures for cell and tissue cultures.
25
MEA Manual
4.14 120MEA with for Use with MEA2100-120-System
120MEA200/30iR-Ti, 120MEA100/30iR-Ti, 120pMEA200/30iR-Ti
120MEA200/30iR-Ti 120pMEA200/30iR-Ti (electrode field with perforation)
The 120MEA200/30iR-Ti has 120 electrodes and can only be used with the MEA2100-System connected
to a headstage HS120 with 120 electrodes. Please refer to the MEA2100-System manual for detailed
information.
The dimension of the glass carrier is 49 x 49 x 1 mm as usual. The MEAs with 120 electrodes are stable
in a temperature range from 0 ° - 125 °C.
The 120MEA200/30iR-Ti contains 120 recording, four reference and four ground electrodes arranged in
a 12 x 12 layout grid. They are embedded in a transparent glass substrate. The contact to the amplifier is
provided by a double ring of contact pads around the rim of the MEA. The standard material for MEAs is
also used for 120MEA200/30iR-Ti: The electrodes are from titanium nitride (TiN) with a silicon nitride (SiN)
isolator, and contact pads and tracks are made of titanium nitride (TiN).
The spacing between the recording electrodes in the 12 x 12 grid averages 100 or 200 μm between
the electrodes. The electrode diameter of 30 μm results in an impedance of approximately 30 - 50 k.
This MEA is also available as perforated 120pMEA200/30iR-Ti. The electrodes are from Titan Gold Titan,
all other MEA parameters are the same. The inner diameter around the electrodes of 3 to 4 mm
2
is perforated and the total area of holes is 12 % of these area.
Using 120MEAs
The same material is used for standard MEAs and 120MEA200/30iR-Ti and 120MEA100/30iR-Ti. Therefore,
they are equally robust and heat-stabilized. They can be autoclaved and coated with different procedures
for cell and tissue cultures.
Using 120pMEA200/30iR-Ti
Perforated MEAs have a glass carrier, but the electrodes are embedded in polyimide foil. Therefore they
are heat stable to 50 °C only, and cannot be autoclaved. Please do not use an ultrasonic bath for cleaning.
26
4.15 Quadrant MEA: 60-4QMEA1000
60-4QMEA1000iR-Ti
The 60-4QMEA1000 has 60 electrodes organized in four quadrants (13 electrodes each) with a center line
(7 electrodes). The electrode diameter is 30 μm, and the interelectrode distance varies: Inside the quadrants
the distance is 200 μm, from quadrant to quadrant the distance is 1000 μm, and to the center line it is
500 μm.
MEA Manual
The 60-4QMEA1000 is available with an internal reference electrode.
The flat, round electrodes are made of titanium nitride (TiN). MEAs with TiN electrodes are very stable.
Therefore, the MEAs can be reused several times and are perfect for long-time experiments (up to several
weeks and even months). The electrode impedance ranges between 30 k and 50 k
Tracks are made of titanium (Ti) and contact pads are made of titanium nitride (TiN); insulation material
is silicon nitride (SiN).
Using 60-4QMEA1000
The 60-4QMEA1000 can be used for a wide variety of applications. They are robust and heat-stabilized.
They can be autoclaved and coated with different procedures for cell and tissue cultures. Generally,
they can be used for acute experiments as well as long-term cultures.
27
MEA Manual
4.16 Square MEA: 60SquareMEA
60SquareMEA200/50iR-Ti
60SquareMEAs have 60 electrodes in an 8 x 8 layout grid with square electrode of 50 x 50 μm size and
interelectrode distances of 200 μm. They are available with an internal reference electrode. You can
connect the internal reference electrode directly to the amplifier's ground and will not need silver pellets
for grounding the bath anymore.
The flat, square electrodes are made of titanium nitride (TiN). The electrode size of 50 x 50 μm guarantees
very low noise. MEAs with TiN electrodes are very stable. Therefore, the MEAs can be reused several times
and are perfect for long-time experiments (up to several weeks and even months). The electrode impedance
ranges about 30 k
Tracks are made of titanium (Ti) and contact pads are made of titanium nitride (TiN); insulation material
is silicon nitride.
Important: MEAs are not symmetrical! That is, why the writing (for example NMI, LEITER, MEA type) on
the MEA chip should be on the right side viewed from the front, with the sockets of the amplifier in the
back. MEAs with one big internal reference electrode should be placed with reference electrode to the left
side in the amplifier. Otherwise, the MEA layout will not match with the pin layout of the channel map in
MC_Rack.
Using 60SquareMEAs
MEAs with square electrodes can be used for a wide variety of applications. They are robust and heatstabilized. They can be autoclaved and coated with different procedures for cell and tissue cultures.
Generally, they can be used for acute experiments as well as long-term cultures.
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4.17 PEDOT-CNT MEAs: 60PedotMEA
60PedotMEA200/30iR-Au
Carbon nanotube stucture of PEDOT electrodes.
MEA Manual
60PedotMEAs have - like standard MEAs - 59 electrodes and one reference electrode that are arranged
in an 8 x 8 layout grid with electrode diameters of 30 μm and interelectrode distances of 200 μm.
The flat, round electrodes are made of PEDOT-CNT carbon nanotube – poly 3,4-ethylene-dioxythiophene.
Contact pads and track material is made of titanium nitride (TiN) covered by a layer of gold (Au).
The insulation material is silicon nitride.
This type of MEA is characterized by very low impedance values of approximately 20 k.They are ideal
for stimulation and have excellent biocompatibility and cell adhesion.
Important: MEAs are not symmetrical! That is, why the writing (for example NMI, LEITER, MEA type) on
the MEA chip should be on the right side viewed from the front, with the sockets of the amplifier in the
back. MEAs with one big internal reference electrode should be placed with reference electrode to the left
side in the amplifier. Otherwise, the MEA layout will not match with the pin layout of the channel map in
MC_Rack.
Using 60PedotMEAs
MEAs with PEDOT-CNT electrodes can be used for a wide variety of applications. They are robust and
heat-stabilized. They can be autoclaved and coated with different procedures for cell and tissue cultures.
Generally, they can be used for acute experiments as well as long-term cultures.
29
MEA Manual
4.18 FlexMEA
FlexMEAs are made of flexible polyimide foil, perfect for in vivo and specific in vitro applications.
Only 12 μm "thick" and weighing less than 1 g, the FlexMEA biosensor is very thin and light weight.
The FlexMEAs are available with 32 (64) recording electrodes plus two (four) indifferent reference
electrodes and two (four) ground electrodes in a 6 x 6 (8 x 9) electrodes grid. More layouts can be
provided on request. The flexible base is perforated for a better contact with the surrounding tissue.
The electrodes are from titanium nitride (TiN), contact pads and track material from pure gold.
FlexMEAs are stable at a temperature range from 10 °C to 125 °C and can be autoclaved.
Using FlexMEAs
Warning: Do not use an ultrasonic bath for cleaning. The manufacturer recommends sterilization
by rinsing with alcohol.
FlexMEAs are usually connected to a head stage preamplifier that is connected to a filter amplifier
or programmable gain amplifier (see also the ME-System product line of Multi Channel Systems).
Via provided adapters FlexMEAs can be connected to 32-channel miniature preamplifiers MPA32I
from Multi Channel Systems for in vivo experiments. There is no need for an adapter if the FlexMEA
should be connected to the 32-channel miniature preamplifier MPA32I-Flex.
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