Multichannel Systems MEA256 User Manual

USB-MEA256-System Manual

Information in this document is subject to change without notice.

No part of this document may be reproduced or transmitted without the express written permission of Multi Channel Systems MCS GmbH.

While every precaution has been taken in the preparation of this document, the publisher and the author assume no responsibility for errors or omissions, or for damages resulting from the use of information contained in this document or from the use of programs and source code that may accompany it. In no event shall the publisher and the author be liable for any loss of profit or any other commercial damage caused or alleged to have been caused directly or indirectly by this document.

Printed: 17. 04. 2014

Multi Channel S

ystems MCS GmbH

Aspenhaustraße 21

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

Microsoft and Windows are registered trademarks of Microsoft Corporation. Products that are referred to in this document may be either trademarks and/or registered trademarks of their respective holders and should be noted as such. The publisher and the author make no claim to these trademark.

Table of Contents

1 Introduction 1

1.1 About this Manual 1

1.2 Welcome to the USB-MEA256-System 2

2 Important Safety Advice 3

2.1 Operator's Obligations 3

2.2 Guarantee and Liability 3

2.3 Important Safety Advice 4

3 Software Installation 5

3.1 Software Installation 5

3.1.1 System Requirements 5

3.1.2 Recommended BIOS settings 6

3.1.3 Driver Installation 6

3.1.4 First Use of MC_Rack 7

4 USB-MEA256-System 9

4.1 The USB-MEA256 Data Acquisition 9

4.2 The USB-MEA256 Filter Amplification 9

4.3 256MEA 10

4.4 256 Thin MEA 11

4.5 256-9well MEA 11

4.6 The USB-MEA256-System 12

4.7 Connecting the USB-MEA256-System 12

4.8 Setting Up the Amplifier 13

4.9 The USB-MEA256 Device 19

4.9.1 Rear Panel 19

5 Troubleshooting 23

5.1 Troubleshooting 23

5.2 No Computer Connection / No Recording Possible 23

5.3 Triggering / Digital Input does not Work 24

5.4 Noise on Single Electrodes 24

5.5 MEA is defective 25

5.6 Overall Noise / Unsteady Baseline 25

5.7 Missing Spikes or Strange Signal Behavior 26

iii

USB-MEA256-System Manual

Appendix 27

6.1 Technical Support 27

6.2 Technical Specifications 28

6.3 Pin Layout 30

6.4 Test Model Probe 32

6.5 Data Sheet 256MEA 33

6.6 Data Sheet 256ThinMEA 34

6.7 Data Sheet 256MEA-STIM-C-Con 36

6.8 Data Sheet 256-9wellMEA 35

6.9 Data Sheet 256MEA-9well-STIM-ADPT 37

6.10 256MEA-Signal Generator 38

6.11 Digital IN / OUT Extension 39

6.12 Scope of Delivery 40

6.13 Contact Information 40

7 Index 41

1 Introduction

1.1 About this Manual

It is assumed that you already have a basic understanding of technical and software terms. No special skills are required to read this manual.

If you are using the device for the first time, please read the Important Safety Advice before installing the hardware and software, where you will find important information about the installation and first steps.

The device and the software are part of an ongoing developmental process. Please understand that the provided documentation is not always up to date. The latest information can be found in the Help. Check also the MCS web site (www.multichannelsystems.com) for downloading up-to-date manuals and help files.

Welcome to USB-MEA256-System

USB-MEA256-System Manual

1.2 Welcome to the USB-MEA256-System

The USB-MEA256-System is a compact and portable stand-alone solution for MEA recordings with integrated amplification, data acquisition, and analog / digital conversion.

It is a highly flexible system: The system acquires data from up to 252 electrode channels, four additional analog channels, and 16 digital IN / OUT channels. The digitized electrode data is transmitted to the connected computer via universal serial bus (High Speed USB 2.0). Thus, it is possible to use any computer as a data acquisition computer, also a laptop.

Data is recorded, graphed, analyzed, and reviewed with the powerful and easy-to-use MC_Rack program from Multi Channel Systems MCS GmbH. You can export the data in standard formats to other programs with the software MC_DataTool. Instead of MC_Rack any other common data processing program or custom software can be used.

The integrated filter amplifier supports 252 electrode channels. The amplification factor of 1100 is fixed. The bandwidth of 1 Hz to 5 kHz is suitable for a broad range of applications, such as spike and field potential recording from neurons or recording of cardiac signals.

Electrode raw data are acquired from the 256MEA and digitized by the analog / digital converter board that is integrated into the main unit. Recorded signals are converted in real time into digital data streams at sampling rates of up to 40 kHz per channel. You will not miss even fast biological signals. Data is transferred to the computer via High Speed USB 2.0 port.

The USB-MEA256-System features a heating element with a PT100 temperature sensor. If you connect a temperature controller TCX to the heating element via D-Sub 9 connector, the heating element guarantees constant temperature conditions for the biological sample, placed on the 256MEA (Microelectrode Array with 252 recording electrodes and four reference electrodes) or on the 256ThinMEA or the 256-9wellMEA respectively.

To control the biological sample on the 256MEA inside the amplifier optically, you can use either an upright microscope or an inverted microscope.

A 16-bit digital input / output (TTL) is available. You can use the digital TTL inputs, for example, for synchronizing stimulation and recording, or for synchronizing the USB-MEA256-System with other systems. The digital TTL outputs can be used for triggering other devices, for example, an imaging setup.

The 16 bit Digital IN / OUT channel can be contacted with a 68-pin MCS standard connector. The bits 0 from the D IN and the D OUT, respectively, are also accessible independently by the D0 IN and D0 OUT Lemo connectors.

The additional analog inputs 1 to 4 are intended for recording additional information from external devices, for example, for recording patch clamp in parallel to the MEA recording, for monitoring the temperature, or for recording voice.

To the Audio Out (3.5 mm phone jack) you can connect an audio system to make the electrical activity audible. This audio output is real time. Headphones or a speaker can be connected directly to the AUDIO OUT. Only one channel at a time can be converted into sound.

2 Important Safety Advice

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 / her 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.

USB-MEA256-System Manual

2.3 Important Safety Advice

Warning: Make sure to read the following advice prior to installation or use of 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: Always obey 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 intended for medical uses and must not be used on humans.

Malfunctions which could impair safety should be rectified immediately.

High Voltage

Electrical cords must be properly laid and installed. The length and quality of the cords must be in accordance with local provisions.

Only qualified technicians may work on the electrical system. It is essential that the accident prevention regulations and those of the employers' liability associations are observed.

 Each time before starting up, make sure that the power supply agrees with the specifications

of the product.

 Check the power cord for damage each time the site is changed. Damaged power cords should

be replaced immediately and may never be reused.

 Check the leads for damage. Damaged leads should be replaced immediately and may never

be reused.

 Do not try to insert anything sharp or metallic into the vents or the case.

 Liquids may cause short circuits or other damage. Always keep the device and the power cords

dry. Do not handle it with wet hands.

Requirements for the installation

Make sure that the device is not exposed to direct sunlight. Do not place anything on top of the device, and do not place it on top of another heat producing device, so that the air can circulate freely.

Warning: The device must not get in contact with fluids! Spilled liquid can damage or even completely destroy the electronics of the amplifier! This is eminently important when using a perfusion system. Take care that the flow rates of the inlet and outlet flow match so that flooding of the amplifier is efficiently prevented.

3 Software Installation

3.1 Software Installation

Please check the system requirements before you install the MC_Rack software. MCS cannot guarantee that the software works properly if these requirements are not fulfilled. Please see the MC_Rack Help or Manual for more information. It is recommended that you check the MCS web site for software updates on a regular basis.

The USB-MEA256-System is a plug and play device. The driver is automatically installed together with the MC_Rack program. It is easier to connect the USB-MEA256-System first to the data acquisition computer and then install MC_Rack.

Important: Please make sure that you have full control over your computer as an administrator. Otherwise, it is possible that the installed hardware does not work properly.

3.1.1 System Requirements

Software: One of the following Windows ® operating systems is required: Windows 7, VISTA or XP (English and German versions supported) with the NT file system (NTFS). Other language versions may lead to software errors.

Hardware (Not required for offline analysis or demo mode): The data acquisition board USB- MEA256-System. If no USB-MEA256-System is present, MC_Rack opens in a simulation mode. A computer with low performance may lead to performance limits more often; therefore, MCS recommends an up-to-date computer optionally with a separate hard disk. Please note that there are sometimes hardware incompatibilities of the USB-MEA256-System and computer components; or that an inappropriate computer power supply may lead to artifact signals. Please contact your local retailer for more information on recommended computer hardware.

Important: You need to have installed the latest USB-MEA256-System driver to operate the

USB-MEA256-System, which is automatically installed with MC_Rack. The installation may

be invalid if the USB-MEA256-System does not respond. Please contact Multi Channel Systems or your local retailer in this case.

USB-MEA256-System Manual

3.1.2 Recommended BIOS settings

Recommended operating system settings

The following automatic services of the Windows operating system interfere with the data storage on the hard disk and can lead to severe performance limits in MC_Rack. These routines were designed for use on office computers, but are not very useful for a data acquisition computer.

1. Turned off Windows System Restore.

2. Windows Indexing Service deselected for all local disks.

3. Optimize hard disk when idle (automatic disk fragmentation) turned off.

4. It is not recommended to run any applications in the background when using MC_Rack. Remove all applications from Autostart folder.

5. Be careful when using a Virus Scanner. These programs are known to disturb MC_Rack, and even data loss may occur.

6. When using an USB-MEA256-System it is recommended to connect a high performance computer with a separate hard disk for program files and data storage. The provided possibility to use up to 252 channels with a sample rate of up to 40 kHz needs high memory capacity. Please remove data and defragment the hard disk regularly to ensure optimal performance.

3.1.3 Driver Installation

3.1.4 First Use of MC_Rack

It is also not recommended to run any applications in the background when using MC_Rack. Remove all applications from the Autostart folder.

Warning: The operating system settings of the data acquisition computer were preconfigured by MCS and should not be changed by the user. Changing these settings can lead to program instabilities and data loss.

Installing MC_Rack with the USB-MEA256-System connected to the computer

The Windows operating system detects a new hardware when the USB-MEA256-System is connected to the computer, if the program has not been installed beforehand. Please make sure the device has power, that is, the power LED is lighting. Simply cancel the "Found New Hardware Wizard" and proceed with the installation of the MC_Rack program.

Connecting the USB-MEA256-System to a computer with installed MC_Rack

If MC_Rack had already been installed on the computer before the hardware was connected, the operating system needs to load the driver once. After this procedure, the USB-MEA256-

System will be automatically recognized by the operating system.

Software Installation

1. Connect the USB-MEA256-System to the USB port of the data acquisition computer.

Please make sure the device has power, that is, the power LED is lighting.

2. Switch the computer on.

The "Found New Hardware Wizard" is displayed.

3. Choose the option "No", not this time and continue with "Next".

4. Choose the option "Install" the software automatically ("Recommended") and continue with "Next".

5. The Wizard will automatically find the appropriate USB-MEA256-System driver. Continue with "Next".

6. The driver installation is finished.

Please check the system requirements before you install the MC_Rack software. MCS cannot guarantee that the software works properly if these requirements are not fulfilled. Please see the MC_Rack help or manual for more information. It is recommended that you check the MCS web site for software updates on a regular basis.

Double-click Setup.exe on the installation volume.

The installation assistant will show up and guide you through the installation procedure.

7. Follow the instructions of the installation assistant.

8. The USB-MEA256-System driver and MC_Rack are installed (or updated) automatically.

4 USB-MEA256-System

4.1 The USB-MEA256 Data Acquisition

Analog input signals are acquired from the data source and digitized by the 256-channel analog / digital converter that is integrated into the main unit. Recorded signals are converted in real-time into digital data streams at sampling rates of up to 40 kHz per channel. You will not miss even the fastest biological signals. Data is transferred to the computer via a High Speed USB 2.0 port.

A 16 bit digital (TTL) input / output channel is available. You can use the digital TTL inputs, for example, for synchronizing stimulation and recording, or for synchronizing the USB-MEA256- System with other systems, video tracking, for example. The digital TTL outputs can be used for triggering other devices.

4.2 The USB-MEA256 Filter Amplification

The filter amplifier combines a band pass filter and the signal amplification in one instrument. The bandwidth of 1 to 5000 Hz is suitable for a broad range of applications, such as spike and field potential recording from neurons or recording of cardiac signals. The digital filter of the MC_Rack program can be used to adjust the pass band and filter the raw data. Please see the MC_Rack help or manual for more information. This way, you are very flexible in designing your experiments. Please note that you may need a higher sampling rate to avoid aliasing. See also the chapter USB-MEA256 Data Acquisition for more information. For slow signals like field potentials, a bandwidth of 1 to 300 Hz is appropriate. If you like to record fast signals like spikes, a pass band of 300 Hz to 5 kHz is suitable. Cardiac signals have fast and slow components; therefore, you usually need a wider bandwidth of 1 Hz to 5 kHz.

Please note that the gain factor of the filter amplifier (1100) is a fixed hardware property; and that you cannot change the gain of the amplifier by software controls. Please also note that the ratio of the output signal to the input signal, that is, the gain, is not a fixed parameter for the complete bandwidth. The gain that was specified for the amplifier, for example, 1100 is not fully reached at the borders of the amplifier's pass band. The general rule is, that at the lower and upper limit of the frequency band, the gain is approximately 70 % of the full gain. Therefore, you should use a bandwidth that is at a safe distance of the signals of interest. Outside the pass band, the gain decreases with the frequency and finally approaches zero.

For more information on gain and filters in general, please refer to standard literature or contact your local retailer.

Raw data from up to 252 electrodes of a microelectrode array MEA is amplified by 252 channels of filter amplifiers that are built very small and compact using SMD (Surface Mounted Devices) technology. The small-sized MEA amplifier combines the interface to the 256MEA probe with the signal filtering and the amplification of the signal. The compact design reduces line pick up and keeps the noise level down. The MEA sensor is placed directly into the small-sized MEA amplifier. When the amplifier is closed, the contact pins in the lid of the amplifier are pressed onto the MEA contact pads. The very close location of the amplifier to the MEA sensor is very favorable concerning a high signal-to-noise ratio.

The amplifier is intended to be used either with inverted or with upright microscopes. The MEA256 amplifier is compatible to most standard microscopes.

The MEA256 amplifier has an integrated heating system for controlling the MEA's temperature. The desired temperature can be easily regulated with a temperature controller TCX.

Connect the internal heating element to a temperature controller's output channel (D-Sub9 socket) with the integrated cable. Do not connect the black heating element cable to the computer!

USB-MEA256-System Manual

If necessary, you can use a Faraday cage or appropriate materials, for example, aluminum foil, for shielding the amplifier. The shielding should be connected to the amplifier's ground.

Warning: Spilled liquid can damage or even completely destroy the electronics of the MEA256 amplifier. Please be careful when setting up your perfusion system and when starting the perfusion. Take care that the flow rates of the inlet and outlet flow match so that flooding of the amplifier is efficiently prevented.

4.3 256MEA

The microelectrode array 256MEA to be used with the USB-MEA256-System contain 252 recording and four ground electrodes on a glass carrier. Contact to the amplifier is provided by a double ring of contact pads around the rim of the MEA. 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 electrode grid is 16 x16 with a spacing of 30, 60, 100 or 200 μm between the electrodes with a diameter of 8, 10 and 30 μm. The electrode diameter of 30 μm results in an impedance of approximately 30 - 50 k. Smaller electrodes have a higher impedance, so the electrode diameter of 10 or 8 μm results in an impedance of approximately 250 - 400 k.

The dimension of the glass carrier is 49 x 49 x 1 mm. MEAs are stable in a temperature range from 0° - 125° C. For information about handling and cleaning, please refer to the MEA manual and / or to the MEA Cleaning Quick Guide. The Pin Layout is described in chapter “Data Sheet 256MEA” in the Appendix. The 256MEA is rotationally symmetrical, so in principle the orientation in the amplifier doesn’t matter. If the orientation is important for your experiments, you can use the engraved serial number as marker. The serial number is on the backside of the MEA in the upper

right edge. In the amplifier the mirrored serial number has to be placed in the upper left edge. This way the 256-electrode layout matchs with the MC_Rack channel layout.

4.4 256 Thin MEA

The glass part of 256 Thin MEAs 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.

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).

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. Please see chapter "Data Sheet 256ThinMEA" in the Appendix.

4.5 256-9well MEA

USB-MEA256-System

A special MEA layout for the USB-MEA256-System is available, the 256-9wellMEA for using together with a 9 well macrolon quadrate. The 9 wells allow, for example drug screening experiments, with up to 9 compounds at a time. The 256-9wellMEA is in principle constructed like the 256MEA, but the electrodes are clustered. There are 23 recording electrodes with a diameter of 30 μm, two bigger recording or stimulation electrodes (2 x 50 μm), and one big reference electrode per each well. Please see chapter "Data Sheet 256-9wellMEA" in the Appendix.

ONNECTING THE USB-MEA256-SYSTEM

USB-MEA256-System Manual

4.6 The USB-MEA256-System

USB-MEA256-System is a high flexible system with integrated amplification, data acquisition,

and analog / digital conversion. Via USB High Speed 2.0 it is possible to transfer a digitally converted and amplified data stream of up to 252 electrode channels to any data acquisition computer.

Note: Using a USB hub for connecting the USB-MEA256-System to the computer is not recommended. The system needs a broad bandwidth for the data transmission. Recording might not be possible, especially if a second device that sends or receives continuous data streams, for example a web cam or USB speakers, is connected to the same USB port.

Top View

4.7 Connecting the USB-MEA256-System

1. Provide a power supply in the immediate vicinity of the installation site.

2. Place all devices on a stable and dry surface, where the air can circulate freely and the devices are not exposed to direct sunlight.

3. Set up the computer (with installed MC_Rack program).

4. Set up the MEA256 amplifier as described in chapter "Setting up the Amplifier".

5. Connect the USB output connector to a free USB 2.0 port of the data proceeding computer. It is not recommended to use an USB hub.

6. Connect the USB-MEA256 via power supply unit to a power outlet of the same electrical system (connected to the same ground / earth wire) as all other components of the setup, for example, the computer or shielding.

7. If necessary, connect the system to an external ground.

8. Connect the internal heating element to the temperature controller's output channel (D-Sub9 socket) with the integrated cable. Do not connect the heating element cable to the computer!

9. Turn the toggle switch at the rear panel on.

10. Check the power LED. It should light up as soon as the power line is connected, and the toggle switch is switched on. If not, check the power source and cabling.

11. Install the MC_Rack program from the installation volume if it is not already installed. The USB-MEA256-System is a plug and play device. The driver is automatically installed together with the MC_Rack program.

12. Start the MC_Rack program and select the USB-MEA256-System as the data source. Please see the MC_Rack help or manual for more details on how to define the data source.

4.8 Setting Up the Amplifier

Open the lid of the amplifier.

USB-MEA256-System

Place the 256MEA test model probe inside. Replace the lid and close it carefully.

First Functional Tests

Each MEA amplifier has been thoroughly tested at the factory site before delivery. However, you may want to perform some tests yourself before you begin your experiment to exclude any damage that might have occurred during transportation, or to fulfill your own guidelines, for instance. Some of the tests will also help you to get to know the basic functions of the hardand software, like a short tutorial. It will take only a few minutes time and can save you time and trouble in the long run. Multi Channel Systems recommends running these tests after the setup of your system before you start your real experiments.

USB-MEA256-System Manual

General Performance / Noise Level

Please use the provided test model probe to test the amplifier immediately after installation. It simulates a MEA with a resistor of 220 k and a 1 nF capacitor between bath and electrode. Use MC_Rack or your custom data acquisition program to record from the test model probe and to check the amplifier. Please see "Test Model Probe" in the Appendix.

Alternative to the test model probe you can use n 256MEA Signal Generator. 256MEA Signal Generator is a convenient tool for USB-MEA256 System users. Use the 256MEA-SG instead of setting up an experiment with biological sample for training, controlling, and troubleshooting purposes. This reduces the number of animal experiments and saves laboratory equipment. Please see the data sheet "256MEA-SG" in the Appendix

Setting up MC_Rack

Please refer to the MC_Rack manual for more information.

1. Start MC_Rack.

2. Click “Data Source Setup” on the “Edit” menu. Select USB-MEA256.

3. Add USB-MEA256 as a data source to your virtual rack.

4. On the “Edit” menu, click “Add Data Display” to add a raw data display to your virtual rack.

5. Click the “Hardware” tab of the USB-MEA256 and enter the sampling frequency in Hz.

Start the data acquisition

1. Click the “Start” button to start the data acquisition. No data is recorded. You see the raw data streams of all 252 channels in the 16 x 16 MEA layout.

2. You may have to adjust the position and span of the axes until you can clearly see the noise level. You should see the baseline with a maximum noise level of +/– 8 μV.

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