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MEA Amplifier with Blanking Circuit for Upright Microscopes

1. 53 MEA Amplifier with Blanking Circuit for Upright Microscopes User Manual Spare Parts Product Heating element with 8 mm bore hole Heating element with 12 mm bore hole Heating element with 23 mm bore hole Heating element Cable assembly 0 5 m 68 pin MCS Standard cable 1 m 68 pin MCS Standard cable 3 m 68 pin MCS Standard cable Ag AgCl pellet Ag AgCl pellet Ag wire Ag wire Solder lug Gold spring contacts Gold spring contacts Gold spring contact comb 3 Pole cable from STG to MEA1060 Red single pole cable from STG to MEA1060 Black single pole cable from STG to MEA1060 Product Number HE Inv 8 HE Inv 12 HE Inv 23 HE Up CA C68x0 5M C68x1M C68x3M P1060 Inv P1060 Up W1060 Inv W1060 Up SL1060 Inv GSC1060 Inv GSC1060 Up GSCC1060 Up C3P CR CB Description For MEA1060 Inv MEA1060 Inv BC amplifier Available with bore holes in different sizes for using smaller or larger microscope objectives The smallest size has the best temperature controlling properties For MEA1060 Up MEA 1060 Up BC amplifier For HE Inv or HE Up For MEA or ME Systems For MEA1060 Inv MEA1060 Inv BC amplifier For MEA1060 Up MEA1060 Up BC amplifier For MEA1060 Inv MEA1060 Inv BC amplifier For MEA1060 Up MEA1060 Up BC amplifier For MEA1060 Inv MEA1060 Inv BC amplifier For MEA1060 Inv MEA1060 Inv BC amplifier For MEA1060 Up MEA1060 Up BC amplifier For MEA1060 Up MEA1060
2. Due to the high electric charge that is applied by the stimulus and the general slow kinetics of electrode discharge the recording from stimulating electrodes is usually not possible shortly after stimulation You might also observe a minor crosstalk on the two channels that have neighbor tracks to the stimulating electrodes on the MEA This is considered a normal behavior of the amplifier The switch artifacts of the internal switches between stimulus input and stimulating electrode of the MEA1060 BC PA also contribute to the artifacts on the stimulating channels The switch artifacts are generally not important for the performance of the stimulus artifact suppression because the charge applied by the stimulus is much higher but the information in this paragraph might be useful for you as a background information The switches generate artifacts that are low but still higher than the noise level As the MEA type and the bath affect the kinetics of the electrode discharge following the switch artifact the amplitude and duration of the switch artifact depend on the experimental set up The switch between stimulus input and stimulating electrode is moved only when the TTL blanking pulse is connected and active and only on stimulating channels selected in MEA Select Therefore you will see a switch artifact on the stimulating channels during the TTL pulse even if you do not send a stimulus pulse to the stimulating electrodes at all 34 Operating
3. Recovery time 0 5 min to 2 min Calibration constant T c R R R for c 259 7 C Thermal resistance 6 C Watt Typical time constant 50 s Pin layout HE for MEA1060 amplifiers pin layout 3 E 5 r a Pin 1 6 Heating Pin 2 5 Temperature sensor supply Pin 3 4 Temperature sensor probe 50 Appendix 7 1 5 Model Test Probe The provided model test probe simulates an MEA with a resistor of 220 kQ and a 1 nF capacitor between bath and electrode for all 60 electrodes and can be used for testing MEA amplifiers Model test probe for MEA amplifiers GND bath Pad electrode 51 7 2 7 3 MEA Amplifier with Blanking Circuit for Upright Microscopes User Manual Contact Information Local retailer Please see the list of official MCS distributors on the MCS web site User forum The Multi Channel Systems User Forum provides the opportunity for you to exchange your experience or thoughts with other users worldwide Mailing list If you have subscribed to the Mailing List you will be automatically informed about new software releases upcoming events and other news on the product line You can subscribe to the list on the MCS web site www multichannelsystems com Ordering Information Product information is subject to change without notice Please contact your local retailer for pricing and ordering information MEA amplifiers Product Product Description Number MEA amplifier for MEA1060 Inv Prob
4. gt 100 600 22ndsweep Y Axis 100 gt uv apa gu 10 15 20 25 30 35 40 45 50 55 Fig 4 The same electrode and pulse protocol but with blanking 35 MEA Amplifier with Blanking Circuit for Upright Microscopes User Manual moorei OE 2029 358sec XAxis 500 ms gt 400 20 488th sweep Y Axis 50 gt yv 50 0 500 0 Fig 5 Voltage driven stimulation 1 V electrode 75 on 30 um TiN electrodes A used MEA 200 30 with some defective electrodes was used for this experiment Defective electrodes 43 52 53 were switched to ground in MEA Select You see only small artifacts on the channels 65 and 85 with tracks next to the stimulating electrode 75 Pin 15 of the MEA 200 30 i R was connected to ground You see a flat line on the stimulating electrode 75 because the electrical state of the electrode after the stimulation results in a saturation of the amplifier 200 10 MEA etal 3691 717sec X Axis ms gt 100 H 200 1740th sweep Y xis yv gt 100 0 _ 1000 0 Fig 6 Voltage driven stimulation 1 V electrode 33 on 10 um TiN electrodes The stimulus artifact suppression is slightly impaired by the higher impedance of the smaller electrodes but still very good You see only small artifacts on the channels 21 and 22 with tracks next to the stimulating electrode 33 Pin 15 of the MEA 200 10 i R was connected to gr
5. 4 x MEA1060 Up amplifier MEAS4 2 2 x TC02 power supply and accessories 55 MEA Amplifier with Blanking Circuit for Upright Microscopes User Manual MEA Switch Product MEA Switch for 4 amplifiers MEA Switch for 2 amplifiers Product Number MEAS4 2 MEAS2 1 Stimulus pulse generators Product 1 Channel stimulus generator 2 Channel stimulus generator 4 Channel stimulus generator 8 Channel stimulus generator 4 Channel stimulus generator 8 Channel stimulus generator Product Number STG1001 STG1002 STG1004 STG1008 STG2004 STG2008 Description The MEA Switch allows you to acquire data from 60 single channels from two MEA1060 amplifiers If you have a 128 channel MC Card MEA 120 System you can even pick 128 channels in total from two MEA pairs with the MEA Switch for four amplifiers MEAS4 2 The selected channels are combined to one Electrode Raw Data stream that is delivered to MC Card by a 68 pin MCS High Grade Cable Description General purpose stimulators for a very wide variety of applications Flexible and easy to use MC_Stimulus software enables complex stimulus waveforms both current and voltage Stimulus isolation units are integrated in the STG for each channel With additional digital trigger in and output Advanced version with 4 additional digital trigger in and outputs About 100 x faster download via USB 16 times more memory for long time stimulati
6. MC Card input labeled MC Card Ch 01 64 or to your custom data acquisition card with a 68 pin MCS standard cable If you have an MEA120 System connect the second MEA amplifier with a 68 pin MCS standard cable to the input for channels 65 128 labeled MC CX64 Ch 65 128 If you are using an MEA Switch connect the amplifiers to the MEA Switch inputs and the MEA Switch outputs to the MC Card Place the MEA amplifier onto the microscope table Connect the internal heating element to a Temperature Controller s output channel D Sub9 socket with the black cable The Temperature Controller is not part of the standard scope of delivery but is included in the MEA System and can also be ordered separately Do not connect the black heating element cable to the data acquisition computer MEA Amplifier with Blanking Circuit for Upright Microscopes User Manual Connect the serial port of the preamplifier to a free RS232 serial port of the computer from which you like to control the MEA amplifier usually the data acquisition computer with the provided RS232 cable Note that you need a separate Com port for each amplifier in use Connect up to two analog outputs of the stimulus generator to the two stimulus inputs of the preamplifier Connect the corresponding ground to the ground inputs Please see the illustrations below for details Connect a digital Sync Out output of the stimulus generator to the Trigger In input of the preamplifier with a stan
7. by all means Of course it is best to completely avoid this situation and consider the following instructions as an emergency measurement only Even with this measurement a severe damage to the instrument cannot be excluded It is very important that the amplifier is not connected or used again before repair to avoid further damage caused by corrosion Even if the initial damage is negligible the additional damage inflicted by corrosion over a longer period of time can completely destroy the electronics Immediately remove the amplifier from the power supply that is unplug the amplifier Do not connect or use it again before repair Contact your local retailer and send the amplifier to Multi Channel Systems for cleaning and repair Multi Channel Systems will check the device and prepare a quote for you depending on the work and material costs needed for repair 43 6 8 MEA Amplifier with Blanking Circuit for Upright Microscopes User Manual Technical Support Please read the Troubleshooting part of the User Manual Help first Most problems are caused by minor handling errors Contact your local retailer immediately if the cause of trouble remains unclear Please understand that information on your hardware and software configuration is necessary to analyze and finally solve the problem you encounter Please keep information on the following at hand Description of the error the error message text or any other useful informatio
8. for MEA electrodes MCS recommends to use only monophasic voltage pulses to make sure that the voltage level of the stimulating electrode is zero at the end of the pulse According to the experience of MEA users voltage pulses should be lt 1 V 100 mV 900mV to avoid damage to electrode and cells See also Potter S M Wagenaar D A and DeMarse T B 2005 Closing the Loop Stimulation Feedback Systems for Embodied MEA Cultures Advances in Network Electrophysiology Using Multi Electrode Arrays M Taketani and M Baudry Springer Wagenaar D A Madhavan R Pine J and Potter S M 2005 Controlling bursting in cortical cultures with closed loop multi electrode stimulation J Neurosci 25 3 680 8 Stimulation with MEA electrodes You can apply two different stimulus protocols to any selection of electrodes Use the MEA Select program to select electrodes for recording and stimulation The stimulation is triggered with a TTL pulse the so called blanking signal Please see Blanking for more information how to set up and time the blanking signal You can also stimulate without blanking for example for testing your setup Under Blanking deselect the Blanking option for disabling the blanking function Important You can only stimulate during an active TTL pulse which is used for triggering the stimulation and the blanking see illustration of switch positions below You can switch off the blanking for test purposes but
9. 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 MEA amplifiers can be ordered with different gain and bandwidth configurations by the user s choice For example typical pass bands would be 1 300 Hz for recording field potentials and 300 3000 Hz for recording action potentials It is also possible to use a broadband amplifier and filter the data with the digital filter of the free MC Rack program Gain settings from 100 to 5000 are possible The amplifier is connected to the data acquisition computer via a single 68 pin MCS Standard cable The analog output signals of the MEA amplifier are then acquired and digitized by the MC Card MEA System or your custom data acquisition system MEA amplifiers have an integrated heating system for controlling the MEA s temperature The desired temperature can be easily programmed with a temperature controller You will not need an incubator during recording all environmental conditions are reliably controlled directly in the MEA dish MEA Amplifier with Blanking Circuit for Upright Microscopes User Manual MEA Amplifier with blanking circuit MEA 1060 BC MEA Select program Electrode button Electrode selec Switch blanking off Save and load array in MEA layout tion mode for test purposes electrode selection mm xj Sim n Blairo Conhg
10. limit of the pass band The low pass filter property of the combined MEA1060 amplifier and MC Card in black is only slightly different For information on the gain and filters of the MC Card data acquisition system please see the ME MEA System User Manual For more information on gain and filters in general please refer to standard literature or contact your local retailer 23 MEA Amplifier with Blanking Circuit for Upright Microscopes User Manual MEA1060 BC Standard frequency band without FA60S 100 70 of specified gain Gain 0 1 1 10 100 1000 10000 100000 Frequency Hz MEA1060 BC Standard frequency band including FA60S MC_Card 1000 70 of specified gain 100 10 Gain 0 1 0 1 1 10 100 1000 3000 10000 100000 Frequency Hz If you use an MEA System the isolated power supply IPS10W that is integrated in the data acquisition computer supplies the power for operating the MEA amplifier The power is distributed along the MCS High Grade cable Please consider that the amplifier can only operate properly if the supply voltage and current specifications are fulfilled especially if you use a custom power supply See also the Technical Specifications and the Troubleshooting section 24 5 2 Operating the MEA Amplifier DC offset correction The internal baseline restore routine of the preamplifier restores the offset to the ground level that is to zero This has to be a slow
11. process If the routine corrected too fast slow signals would be eliminated as well All electrodes on an array have different DC offsets at the beginning of an experiment The DC offsets are amplified by the preamplifier and the amplified output signal of the preamplifier is likely to exceed the input range of the following filter amplifier In order to eliminate this DC offset a so called baseline restorer is integrated in the preamplifier For signals in the usual measurement range the baseline restore routine acts like a high pass filter with a very low cut off frequency of roughly 0 01 Hz but unnaturally high signals like stimulus artifacts are limited to a negligible value Due to the low cut off frequency the baseline restorer takes some time to stabilize after switching on the amplifier or after replacing the MEA One to two minutes are quite normal During this time the filter amplifier input will be overloaded and you will see only a straight line with very low noise This is considered a normal behavior and should not trouble you Please wait until the baseline restore routine has been completed When replacing an MEA the stabilizing time can be greatly reduced by connecting all electrodes to ground during the opening of the amplifier and change of the MEA The connection to ground results in lower electrode offsets Therefore you should always use the Change MEA command when replacing an MEA See also the chapter First Tests and T
12. the MEA Amplifier 5 7 Examples with Different MEA Types In the following you will find typical examples for stimulus artifact suppression with standard MEA and electrode types under standard experimental conditions Monopolar voltage driven stimulation 1 V monophasic 100 pis duration at a 24 ms interval Wait 0 MEA filled with PBS silver pellet or internal reference electrode as bath electrode Under these conditions the stimulus artifact suppression performance showed no difference whether the internal reference electrode or a silver pellet was used except for EcCoMEAs where the performance was sometimes much better with the silver pellet The data acquisition was performed with MC Rack at a sampling rate of 25 kHz These examples are intended to give you an impression of the results that you can expect with the MEA1060 BC amplifier but please note that the results may vary depending on your experimental settings please see also the recommendations under Stimulus Artifact Suppression Blanking Please see also the step by step tutorial on Stimulation and Recording under First Tests and Tutorial Used 200 30 MEA E Blanking Off 10 346 332sec XAxis 500 p ms gt 400 600 i 34Xdsweep Ys 100 p 1000 1000 5 10 15 20 25 30 35 40 45 50 55 Fig 3 Stimulus artifacts with switched off blanking on a typical non stimulating 30 uum electrode E Blanking On fel 21748sec XAxis 500 ms
13. 0 us can be necessary A factory set Wait of 40 us is added to all user defined Wait values For example a user defined Wait of 0 results in a total delay of 40 us Electrode impedance A parameter that was found to be quite important for the stimulus artifact suppression performance is the electrode impedance Electrodes that are bigger 30 uim or TiN electrodes show a better blanking performance compared to very small 10 um or PT electrodes 3D MEAs with a higher impedance Please note that a hydrophilic electrode has a lower impedance and therefore also shows a better blanking performance New MEAs are generally very hydrophobic and should be hydrophilized before use please see the MEA User Manual for more information Note When using current driven stimulation the combination of electrode impedance and current amplitude may lead to high voltages Please regard the maximum input voltage of 5 V of the MEA1060 BC amplifier Otherwise an unpredictable behavior of the amplifier can be expected In rare cases even damage to the amplifier electronics might occur MCS recommends to use voltage driven stimulation only 32 Operating the MEA Amplifier Single pulses vs repeated pulses Interestingly the behavior of MEA electrodes when applying pulses that are repeated after some milliseconds is much better than when a single pulse is applied You can observe that the kinetics improve that is you need a shorter Wait following the ap
14. Deactivate the Change MEA mode only after having completely set up the amplifier including grounding the bath and shielding the amplifier Otherwise it can take very long several seconds to minutes until the amplifier has recovered and is ready for operation Mounting the MEA Probe In the MEA Select program click Change MEA All electrode inputs are connected with the amplifier s ground This helps avoiding a large DC offset and reduces the baseline restoring time significantly See also the chapter Operating the MEA Amplifier Signal Amplification and Filters Open the lid of the MEA amplifier Place the MEA probe inside The writing NMI should be on the right side Otherwise the MEA layout will not match with the pin layout This is not very important for standard MEAs with a symmetric electrode field as long as you document the orientation for your own reference but it is important for asymmetric MEAs for example with internal reference electrode Replace the lid and close it carefully Do not unpress the Change MEA button until you have grounded the bath and replaced the shielding that is until the setup has been completely finished 26 Operating the MEA Amplifier Grounding the bath You can ground the bath with a plain silver wire or with an Ag AgCl pellet Only the Ag AgCl electrode provides a stable intrinsic potential In practice the plain silver wire will be ok for 90 of applications If you do not achie
15. MC_Card MEA1060 Inv amplifier TC01 power supply and accessories Complete with 5 MEAs data acquisition computer with MC Card 2 x MEA1060 Inv amplifier MEAS2 1 TCO2 power supply and accessories Complete with 5 MEAs data acquisition computer with MC Card MEA1060 Up amplifier TC01 power supply and accessories Complete with 5 MEAs data acquisition computer with MC Card 2 x MEA1060 Up amplifier MEAS2 1 TCO2 power supply and accessories Complete with 5 MEAs data acquisition computer with MC Card MEA1060 Inv amplifier TC02 PHO1 power supply and accessories Complete with 5 MEAs data acquisition computer with MC Card 2 x MEA1060 Inv amplifier MEAS2 1 2 x TCO2 2 x PHO1 power supply and accessories Complete with 5 MEAs data acquisition computer with MC Card MEA1060 Up amplifier TC02 PHO1 power supply and accessories Complete with 5 MEAs data acquisition computer with MC Card 2 x MEA1060 Up amplifier 2 x TC02 2 x PHO1 power supply and accessories Complete with 5 MEAs data acquisition computer with MC Card MEA1060 Inv amplifier TC02 power supply and accessories Complete with 5 MEAs data acquisition computer with MC Card 4 x MEA1060 Inv amplifier MEAS4 2 2 x TCO2 power supply and accessories Complete with 5 MEAs data acquisition computer with MC_Card MEA1060 Up amplifier TC02 power supply and accessories Complete with 5 MEAs data acquisition computer with MC Card
16. ON AR Double click a channel in the display to have a closer look E Model Test Probe Noise Level OP x 5 000 sec xAxis 1000 y ms 00 H 5000 v Pea Bth sweep Yass 20 N 200 200 100 150 200 300 350 400 14 4 3 4 4 First Tests and Tutorial Computer Connection Testing the computer connection The MEA Select program automatically detects and lists all serial ports of your computer Start MEA Select Select the serial port to which you have connected the MEA preamplifier COM1 COM2 and so on from the drop down list Port Comi Y Test Conn Click Test Connection A valid computer connection should be confirmed by OK If not please check all cables and connections Note You can control multiple MEA amplifiers from the same computer by starting several instances of the MEA Select program Connect the amplifiers to different serial ports and select the appropriate serial port for each amplifier in the MEA Select program Stimulation and Recording In this chapter we provide a step by step instruction for first tests that we think useful for learning more about the features and behavior of the amplifier It is assumed that you will use MCS components MEA System and stimulus generator for the complete setup Please make sure that you have set up the system as described in the chapter Setting Up and Connecting the MEA Amplifier or likewise if you use other
17. Q9 66269 69 G9 89 6 C9 89 45 MEA Amplifier with Blanking Circuit for Upright Microscopes User Manual The following illustration shows the standard pin layout of the socket on the amplifier The list below shows the assignment of the electrodes to the pins of the socket Pin 1 is the ground of the power supply pin 2 is the ground of the signal that is where the signal is referred to Both pins are already internally connected inside the amplifier If you are planning to build a custom setup with a home made filter amplifier please be careful with the input of the filter amplifier Since the MEA1060 BC is a quasi DC coupled preamplifier the input into the filter amplifier has to be AC coupled that is there has to be a capacitor at the input before the signal is led into the operational amplifier Otherwise you will have problems with the offset of the metal electrodes and your filter amplifier will go into saturation Channels A1 AA are the four additional analog inputs of the MC Card that are not used by the MEA amplifier You can access channels A1 A3 via the BNC sockets labeled Analog IN on the rear side of the data acquisition computer of the MEA System see also MEA System User Manual 68 Pin MCS standard socket O00000 Q9 5 9 CO 2 Pin 1 GNDP power ground Pin 2 GNDS signal ground Pin 3 62 Electrode channels see separate list Pin 63 66 Channel A1 A4 Pin 67 Positive voltage supply Pin 68 Negat
18. The pass band of the filter amplifier should be chosen according to the signal type It is generally useful to set the upper limit of the amplifier near the highest expected signal frequency but also at a safe distance to make sure that the full gain is used for signal amplification For slow signals like field potentials a bandwidth of 1 300 Hz is appropriate If you like to record fast signals like spikes a pass band of 300 Hz to 3 kHz is suitable Cardiac signals have fast and slow components therefore you usually need a wider bandwidth of 1 Hz to 3 kHz Multi Channel Systems provides custom amplifiers with a bandwidth of your choice from 0 1 Hz to 10 kHz Please note that it is often useful to acquire the data with a broadband amplifier and use the digital filter of the free MC Rack program to change the pass band and filter the raw data This way you are much more flexible in designing your experiments As a further advantage you can see the original not filtered data as well This is especially important because all filters are known to distort signals On the other hand you may need a higher sampling rate to avoid aliasing and you will have a lower signal to noise ratio The standard gain of a MEA amplifier is 1200 1100 in case of a MEA amplifier with blanking circuit which is fine for most applications but MCS can also provide amplifiers with a gain of your choice from 100 to 5000 as well For large signals for example from wh
19. Up BC amplifier With ground not necessary for MEA1060BC amplifiers 54 MEA Systems Product MEA recording system for inverted microscopes 60 electrode channels MEA recording system for inverted microscopes 60 electrode channels 2 MEA amplifiers MEA recording system for upright microscopes 60 electrode channels MEA recording system for upright microscopes 60 electrode channels MEA recording system for inverted microscopes with advanced perfusion 60 electrode channels MEA recording system for inverted microscopes with advanced perfusion 60 electrode channels MEA recording system for upright microscopes with advanced perfusion 60 electrode channels MEA recording system for upright microscopes with advanced perfusion 60 electrode channels MEA recording system for inverted microscopes 120 electrode channels MEA recording system for inverted microscopes 120 electrode channels MEA recording system for upright microscopes 120 electrode channels MEA recording system for upright microscopes 120 electrode channels Product Number MEA60 Inv System MEA60 Inv 2 System MEA60 Up System MEA60 Up 2 System MEA60 Inv System E MEA60 Inv 2 System E MEA60 Up System E MEA60 Up 2 System E MEA120 Inv System MEA120 Inv 4 System MEA120 Up System MEA120 Up 4 System Appendix Description Complete with 5 MEAs data acquisition computer with
20. a display to your virtual rack Starting the recording On the Measurement menu click Start to start the recording You see the raw data streams of all 60 channels in the typical MEA layout You may have to adjust the position and span of the axes until you can clearly see the noise level During the first minute you will see the baseline on all channels because the filter amplifier is still saturated All electrodes have a different DC offset at the beginning of an experiment The internal baseline restore routine restores the offset to the ground level that is to zero During this time you will not see any true signals or noise See also the chapter Operating the MEA Amplifier Signal Amplification and Filters After about one minute the baseline restorer has corrected the DC offset and you see true signals You should see the baseline with a maximum noise level of 8 uV The following screen shot shows a recording from a typical MEA amplifier with a model test probe and a sampling rate of 25 kHz 13 MEA Amplifier with Blanking Circuit for Upright Microscopes User Manual E Model Test Probe Noise Level OF x 85 000 sec XAxis 1000 ms gt 00 E 9 5000 v Pea EN SBhsweep YAxis 20 p w 200 200 Sho 200 4010 200 4010 200 4010 200 4010 200 4010 200 4010 200 4010 200 40 41 51 61 71 je NEP Le La a a s j M Ot a aa DO OH A PN AP AIR AAOS ANON SAN
21. adequate 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 MEA Amplifier with Blanking Circuit for Upright Microscopes User Manual 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 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 prov
22. amplifier 4 Switch to the MC Rack display All 17 MEA Amplifier with Blanking Circuit for Upright Microscopes User Manual You can see that the noise level of the grounded electrodes is reduced The effect is quite small because the model test probe has no defective electrodes and shows a fine low noise level on all electrodes E Ground Electrodes 36 46 56 D x 350 200 sec XAvis 1000 ms z i 350th sweep Ys 10 p 100 50 0 50 0 50 0 50 0 50 0 50 0 21 41 51 61 71 Mri Min dae gs cyte hit Pali ule dol lud dd d a aa d Lu ln ial baa ML cumul MEUM Ma Mij ERAI Stimulation without blanking Usually you will always use the blanking when you stimulate But it is possible to switch off the blanking for testing your setup In MC Rack bring the triggered display to the front Make sure you have connected the digital Sync Out output of the stimulus generator to the digital channel 1 bit 0 of the MC Card Otherwise you have to select the appropriate bit in the Trigger Detector C Tonus A eoessessnssoseenseaoeasencTir Eines 2 Stat and Endo on ee In MEA_Select under Blanking deselect Blanking Blanking Blanking Under Stimulation select the appropriate stimulus input Stim A or Stim B 18 First Tests and Tutorial 4 Click any electrode that you like to use for stimulation for example 53 The stimulating electrodes are marked by a colo
23. anual Important Information and Instructions Operator s Obligations Guaranty and Liability Important Safety Advice Terms of Use for the Program Limitation of Liability First Use of the MEA Amplifier Welcome to the MEA Amplifier Installing the Software Setting Up and Connecting the MEA Amplifier First Tests and Tutorial First Functional Tests General Performance Noise Level Computer Connection Stimulation and Recording Operating the MEA Amplifier Signal Amplification and Filters Temperature Control Mounting the MEA Probe and Grounding the Bath Grounding Defective Electrodes Stimulation Stimulus Artifact Suppression Blanking Examples with Different MEA Types Service and Maintenance Troubleshooting About Troubleshooting Error Messages Noise on Single Electrodes Unsteady Baseline Artifacts on All Channels Unpredictable Noise and Artifacts Liquid Spilled onto Amplifier Technical Support Appendix Technical Specifications 7 1 1 Pin and MEA Layout 7 1 2 MEA1060 Up BC 7 1 3 FA60S BC 7 1 4 Heating Element 7 1 5 Model Test Probe un BWW Ww O ONN 13 13 13 15 15 23 23 25 26 28 30 31 35 38 39 39 39 39 40 41 42 43 44 45 45 45 48 49 50 51 7 2 Contact Information 7 3 Ordering Information 8 Index 52 52 57 1 1 Introduction Introduction About this Manual This manual comprises all important information about the first installation of the har
24. components You can use the provided model test probe for your first experiment First you have to set up your stimulus generator and MC Rack Then you can start MEA Select to operate the MEA amplifier Of course you can also change your MC Stimulus or MC Rack settings during amplifier operation Setting up the stimulus generator Start MC Stimulus 15 MEA Amplifier with Blanking Circuit for Upright Microscopes User Manual Open the demo stimulus file on the installation volume You can choose between a monophasic and biphasic stimulus The voltage demo stimulus is a monophasic or biphasic pulse with a duration of 100 us for each phase and an amplitude of 1 V 1 V The pulse is repeated continuously each 24 ms with the Repeat feature of MC Stimulus The Sync Out trigger pulse for triggering the MEA amplifier and the MC Card is 100 us longer than the stimulus pulse On the STG menu click Download all to download the file onto the stimulus generator Data acquisition with MC Rack Start MC Rack Open the demo rack file MEA1060BC demo rck on the installation volume It is a simple rack with only a Trigger Detector one continuous and one triggered Data Display You will need a trigger for stimulation and blanking and for triggering the triggered display Bring the continuous display to front Start the recording by clicking Start Operating the MEA amplifier with blanking circuit Start MEA Select On the left y
25. d 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 Guaranty 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 guaranty 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 Guaranty 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 In
26. dard BNC cable If you use a complete MEA System connect the same Sync Out output to the first digital input bit of the MC Card Split the Sync Out output by using a T connector You should 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 for example to the screws of the cover Please see also the separate handout MEA Microelectrode Systems for setup suggestions with detailed illustrations The following illustration shows a suggested setup for a standard MEA60 System with stimulus generator and blanking circuit Computer Electrode selection via RS232 Software MC Rack MC Stimulus MEA Select C68x2M MEA1060BC Sync Out trigger gt Blanking signal Stimulus generator control via RS232 10 First Use of the MEA Amplifier Connecting the amplifier to the stimulus generator The following illustration shows the recommended setup for connecting a stimulus generator to the MEA amplifier with blanking circuit The amplifier is electrically connected to the stimulus generator only during the short time of the blanking pulse Therefore a shielded cable that is usually used for preventing the pick up of noise is not necessary The first illustration shows a typical monopolar stimulation setup One output channel usually U of the stimulus generator is connected to either stimul
27. dware and software and about the daily work with the instrument It is assumed that you have already 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 printed manual and Help are basically the same so it is up to you which one you will use The Help offers you the advantage of scrolling through the text in a non linear fashion picking up all information you need especially if you use the Index the Search function and the Browse Sequences If you are going to read larger text passages however you may prefer the printed manual 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 2 1 2 2 Important Information and Instructions Important Information and Instructions 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 qualifie
28. e are problems with the contacts Please see the Spare Parts list under Ordering Information Warning Please be very careful when handling the amplifier cleaning the device or replacing contact pins The pins can be easily damaged 38 6 1 6 2 6 3 Troubleshooting Troubleshooting About Troubleshooting The following hints are provided to solve special problems that have been reported by users Most problems occur seldom and only under specific circumstances Please check the mentioned possible causes carefully when you have any trouble with the product In most cases it is only a minor problem that can be easily avoided or solved If the problem persists please contact your local retailer The highly qualified staff will be glad to help you Please inform your local retailer as well if other problems that are not mentioned in this documentation occur even if you have solved the problem on your own This helps other users and it helps MCS to optimize the instrument and the documentation Please pay attention to the safety and service information chapter Important Safety Advice and Service and Maintenance in the User Manual Help Multi Channel Systems has put all effort into making the product fully stable and reliable but like all high performance products it has to be handled with care Error Messages MEA Select error messages are displayed in the box below the port settings They show up if the computer fail
29. e interface and 60 channel pre and filter inverted microscopes amplifier with custom gain and bandwidth MEA amplifier for upright MEA1060 Up microscopes MEA amplifier with MEA1060 Inv BC Probe interface and 60 channel pre and filter blanking circuit for amplifier with custom gain and bandwidth inverted microscopes The blanking circuit prevents the amplifier MEA amplifier with MEA1060 Up BC from getting saturated and thus prevents blanking circuit for stimulus artifacts upright microscopes 52 Appendix Accessories Product Adapter for MEAs with 8 special electrodes for stimulation Holder with M3 threads 1 Channel temperature controller 2 Channel temperature controller Perfusion cannula with programmable fluid temperature Signal divider for MEA Systems Product Number MEA STIM Adapter MPM3 TCO1 TCO2 PHO1 SD MEA Description For use with MEAs 200 30 Ti stim or 200 30 ITO stim and MEA1060 Inv amplifier For fixing tools with M3 threads next to the MEA PID based technology set point temperature reached fast within 30 s to 5 minutes control temperature range from ambient temperature to 50 C Temperature can be programmed with the temperature controller TCO1 or TCO2 Placed between an MEA1060 amplifier and MC_Card permits to select any channel does not interfere with the data acquisition for example for connecting an oscilloscope or other devices to single channels
30. ectrode 33 In this example we have used a Wait of 200 us 20 First Tests and Tutorial E Stimulus A on 53 and B on 33 with Blanking OF x 9 608 sec Axis 500 gt ms gt WU j 60 0 V Peak 10th sweep YAxis 100 wV gt 000 1000 5 0 10 15 20 25 30 35 Wait settings You can use the Wait for optimizing the electrode s behavior The Wait parameter is the delay between switching the electrodes from stimulation back to recording that is the stimulating electrodes are disconnected from the stimulus input at the end of the trigger signal and all electrodes are connected to the amplifier input at the end of the Wait period The Wait helps avoiding cross talk between stimulating and non stimulating electrodes as well as preventing switch artifacts The length of the Wait depends on several factors electrode performance stimulus amplitude for example and has to be optimized empirically for each experimental setup Enter increasing Wait values and monitor the performance of the stimulus artifact suppression 21 5 1 Operating the MEA Amplifier Operating the MEA Amplifier Signal Amplification and Filters The MEA amplifier with blanking circuit is a 60 channel preamplifier with a broad bandwidth Filter specifications and gain are defined by the following filter amplifier Different filter settings are used for different applications to enhance the signal to noise ratio
31. electrodes No 15 16 24 25 26 35 and 47 show a very high noise level 1041 993 sec XAxis 500 gt ms gt 300 6 amp 0 1031stsweep YAxis 20 wV 200 _ _ 200 1 Under Stimulation select Ground Stimulation C Not Stim Stim B C StmA Ground 2 Click any electrodes that you like to ground Grounded electrodes show no electrode number only a blank button 21 31 41 51 61 71 A2 22 32 2 52 62 72 82 13 z3 83 43 53 63 73 83 As JL Ms 44 54 sal LIL 45 ss 51 isileli s51 27 37 _ 5 sz 28 se 48 se ee A EA an en an o a is le BID a E is s t re isle ale ELLI B ceo en e co 3 Click Download to download this information on the MEA amplifier 28 Operating the MEA Amplifier You can clearly see the difference between the high noise level and the zero line of the grounded electrode 533050sec XAxis 500 p ms gt 400 600 i 587th sweep Y4wis 20 p W 200 5 200 214866sec Xs 500 ms gt 300 6 amp 0 213th sweep YAws 20 p 200 200 im Defective Electrode on Ground OF x 8 601 sec XAxs 500 gt ms gt 400 p E 600 Shsweep YAsis 20 gt uV 200 200 29 5 5 MEA Amplifier with Blanking Circuit for Upright Microscopes User Manual Stimulation Recommended stimulus protocols
32. he TTL pulse because the connection is interrupted MCS recommends to try out 500 pis and then decrease the time length stepwisely for optimization if you observe problems with the artifact suppression performance The AutoSync feature of the STG 2000 series makes it easy to adapt the Sync output of your stimulus protocol 31 MEA Amplifier with Blanking Circuit for Upright Microscopes User Manual The following example shows a blanking signal programmed with MC Stimulus of 200 us length for a monophasic voltage pulse of 100 us length perium lo my nv 22900 us mv Y Wait settings A delay up to 5000 us between stopping stimulation end of TTL pulse and restarting the recording can be programmed with the Wait property in the MEA Select program in order to optimize the blanking The stimulating electrodes are disconnected from the stimulus input at the end of the trigger signal and all electrodes are connected to the amplifier input at the end of the Wait period The Wait helps avoiding cross talk between stimulating and non stimulating electrodes as well as preventing switch artifacts of the amplifier The length of the Wait depends on several factors electrode performance stimulus amplitude for example and has to be optimized empirically for each experimental setup Generally the lower the amplitude of your stimulus is the shorter can be the blanking signal For strong stimuli a Wait of up to 40
33. isions 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 mains 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 Keep the device and the power cords always 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 Never cover the device not even partially so that the air can circulate freely Otherwise the device may overheat Use and keep the device only in a dry environment Fluids or damp air may damage or destroy the device Spilled liquid can damage or even completely destroy the electronics of the MEA amplifier Avoid it by all means 2 4 2 5 Important Information and Instructions Terms of Use for the Program You are free to use the program for its intended purpose You agree that you will not deco
34. ive voltage supply 46 Assignment pin to electrode 68 Pin socket pin o N DU HR WW 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 MEA electrode 47 48 46 45 38 37 28 36 27 17 26 16 35 25 15 14 24 34 13 23 12 22 33 21 32 31 44 43 41 42 68 Pin socket pin 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 MEA electrode 52 51 53 54 61 62 71 63 72 82 73 83 64 74 84 85 75 65 86 76 87 77 66 78 67 68 55 56 58 57 Appendix 47 MEA Amplifier with Blanking Circuit for Upright Microscopes User Manual 7 1 2 MEA1060 Up BC Operating temperature Storage temperature Dimensions W x D x H Weight Supply voltage external power supply Supply current Number of stimulus input channels Maximum recommended stimulus input voltage Number of analog input channels Input voltage Input impedance Input noise Noise density Number of analog output channels Output voltage Output current Output impedance Bandwidth Gain Microscope compatibility Distance focal plane to microscope table 48 10 C to 35 C 0 C to 50 C 165 mm x 165 mm x 20 mm 29 mm with sockets 800 g 6 5 VDC to 9 VDC 350 mA 2 5V 60 0 to 4 mV 10 Q parallel to 10 pF lt 800 nV e 15nV 4 Hz 60 5V 10 mA 300 Q 0 02 Hz to 8500 Hz S
35. lf 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 hard and 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 General Performance Noise Level Please use the provided model test probe to test the amplifier immediately after installation The model test probe is already mounted on the amplifier It simulates an MEA with a resistor of 220 kO and a 1 nF capacitor between bath and electrode Use MC Rack or your custom data acquisition program to record from the model test probe and to check the amplifier Setting up MC Rack Please refer to the MC Rack User Manual for more information Start MC Rack Open the file MEA Display rck on the installation volume This basic rack contains the virtual MC Card instrument with appropriate gain settings and a continuous raw data display OR Set up the rack on your own Click Set Channel Layout on the Edit menu Select a 2 dimensional MEA layout Add the MC Card to your virtual rack Click the Hardware tab of the MC Card and enter the amplifier gain standard 1100 On the Edit menu click Add Data Display to add a raw dat
36. mpile reverse engineer or otherwise attempt to discover the source code of the software Limitation of Liability Multi Channel Systems MCS GmbH makes no guaranty as to the accuracy of any and all tests and data generated by the use the software It is up to the user to use good laboratory practice to establish the validity of his findings To the maximum extent permitted by applicable law in no event shall Multi Channel Systems MCS GmbH or its suppliers be liable for any special incidental indirect or consequential damages whatsoever including without limitation injuries damages for data loss loss of business profits business interruption loss of business information or any other pecuniary loss arising out of the use of or inability to use the program or the provision of or failure to provide Support Services even if Multi Channel Systems MCS GmbH has been advised of the possibility of such damages 3 1 First Use of the MEA Amplifier First Use of the MEA Amplifier Welcome to the MEA Amplifier MEA amplifier with blanking circuit setup Sync Out from RS232 stimulus generator MEA Select program Filter amplifier and data acqui sition Stimulus A Stimulus B Raw data from up to 60 electrodes of a microelectrode array MEA is amplified by 60 channels of pre and filter amplifiers The MEA sensor is placed directly into the small sized MEA preamplifier with blanking circuit MEA1060 BC PA When the amplifier
37. multichannel systems MEA Amplifier with Blanking Circuit for Upright Microscopes User Manual eeeeeeee 9990909 eeeeeeene LEN 999 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 2004 2005 Multi Channel Systems MCS GmbH All rights reserved Printed 2006 05 17 Multi Channel Systems MCS GmbH AspenhaustraBe 21 72770 Reutlingen Germany Fon 49 71 21 90 925 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 trademarks Table Of Contents Introduction About this M
38. n and of the context in which the error occurred Try to remember all steps you had performed immediately before the error occurred The more information on the actual situation you can provide the easier it is to track the problem The serial number of the device You will find it on the device Description of the data acquisition system The operating system and service pack number on the connected computer The hardware configuration Isolated Power Supply IPS10W microprocessor frequency main memory hard disk of the connected computer This information is especially important if you have modified the computer or installed new hard or software recently Other connected hardware Appendix 7 Appendix 7 1 Technical Specifications 7 1 1 Pin and MEA Layout The layout of standard MEA electrodes follows the scheme of a standard grid 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 The numbering follows the standard order from left to right and from top to bottom The two ground inputs G of the preamplifier are internally connected so it does not matter which one you use Pin and MEA layout BOOQOOOOOQOOOOOOOE MEA Layout 0 6 6 6 000600000 O 69 OOOO 69 G9 69 6 G9 OCOO O OOOOOOOOO 9 GYX9XX999 G9 2 9 Go 29 67 69 65 69
39. ole heart preparations you need a lower gain to prevent a saturation of the amplifier Please note that the gain is a fixed hardware property and that you cannot change the gain of the amplifier by software controls For more information on the technical specifications of your amplifier please see the separate data sheet that is delivered with each amplifier Please 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 1200 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 Y2 2 that 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 The first illustration shows the broad frequency band of the MEA1060 BC amplifier alone without Filter Amplifier the following illustration shows a typical frequency band of the MEA amplifier with standard gain and bandwidth in blue Output signal amplitudes were divided by the input signal amplitude and the resulting gain was plotted versus the input signal frequency on a logarithmic scale A straight line at approximately 70 96 of the specified gain intersects the plotted curve at the lower and upper
40. on 56 Index 8 Index 57 MEA Amplifier with Blanking Circuit for Upright Microscopes User Manual 3 SD MEA eet eras 35 A Aliasing z ken 8 San eek aay 23 B Band pass Dand sae 23 Bandwidth esses 23 C Change MEA sese 26 COM serial POTT sss 15 Computer connection sssrinin ariin 15 Connecting uk ades 9 Contact Information 52 D Defective Electrodes Grounding essent 28 Delay Wait settings 31 E ECOMEAS 3 323333 a a adapa aa nu 35 Error Messages 39 F Faraday cage see 9 Filters bandwidth esses 23 Frequency band iiie direi nns 23 G GAIN E EAA 23 Grounding Defective Electrodes 28 H Heating eph 25 l Installing SoftWate tete 9 IPSTOW iiidnse eiecit d 9 58 M ME Gata eel nie ees 9 MEA differences in blanking performance sehditves feriis vase shes esatto code tds ae ee 35 layOUt aiat ded edet 45 mounting esses einen 26 Model Test Probe usssss 51 Mounting MEA Probe sssssseeereen 26 N Noise troubleshooting 39 Noise Level testing eie pre EC dna 13 P Pin layo reena a eastern isdiet ale 45 R hRS232 5 eodeni e e oon 15 S Serial port connecting ieies nennt 15 Signal amplification esses 23 Signal to noise
41. ore carefully next time Contact pin is defective Possible causes The contact pins are contaminated Clean the contact pins carefully with a smooth and clean tissue and pure 100 96 alcohol The contact pins are damaged Replace the contact pins carefully Please see the Spare Parts list under Ordering Information Try to handle and clean the contact pins more carefully next time Unsteady Baseline The baseline is unstable signals are jumping or drifting Possible causes Bath electrode is not connected to ground Connect the internal or external bath electrode to one of the ground inputs of the amplifier as described in Mounting the MEA Probe AgCI bath electrode needs is not well chlorided Rechloride the electrode or use a new one The MEA has an internal reference electrode and pin 15 is connected to ground appropriately but the orientation of the MEA inside the amplifier is wrong In this case the wrong standard size for recording electrode is connected to ground but not the reference electrode Open the amplifier and check the orientation of the MEA and the reference electrodeas described in Mounting the MEA Probe 40 6 5 Troubleshooting Artifacts on All Channels You see strange artifacts on all channels This behavior can be caused by an insufficient supply power Please see the Technical Specifications section If the voltage drops beyond a critical level the amplifier cannot operate properly re
42. ou see the MEA layout button array Here you can select any electrodes for stimulation or connect them to ground The default state of all electrodes is selected for Recording Not Stim This is indicated by the neutral grey background of the electrode buttons Accordingly you will see the standard noise level on all channels in the continuous display in the MC Rack program The triggered display is still empty because you have not started triggering the stimulation and the MC Card yet 21 31 41 51 61 71 12 22 32 42 52 2 2 82 13 23 33 43 53 63 73 83 14 24 34 44 54 64 74 84 15 25 5 45 55 65 75 851 16 26 36 46 56 66 76 86 172 27 37 7 57 67 2 871 28 se e se 68 zel All 16 Grounding electrodes First Tests and Tutorial You can connect any electrode to ground Usually you will ground defective electrodes Now we are trying out this feature even if it makes no sense with the MEA model test probe 1 Under Stimulation select Ground r Stimulation C Stim C Not Stim Stim B Ground 2 Click any electrodes that you like to ground for example electrodes 36 46 and 56 Grounded electrodes show no electrode number only a blank button 21 31 41 si en zi ae ze se 42 se 62 72 ee 3 23 3 43 531 63 3 ea ael zs se e se n zelas 28 36 48 se 8 7s 3 Click Download to download this information on the MEA
43. ound 36 Operating the MEA Amplifier 3D MEA 1271 253sec X Awis 223rd sweep Y Axis Fig 7 Voltage driven stimulation 1 V electrode 33 on 3D Pt electrodes The stimulus artifact suppression is slightly impaired by the properties for example higher impedance of Pt electrodes but still very good You see only small artifacts on the channels 21 and 22 with tracks next to the stimulating electrode 33 EcoMEA Triogered Date o 1098 527 sec X Awis ms gt 100 280th sweep Y Axis Wo 500 J 0 Fig 8 Voltage driven stimulation 1 V electrode 33 on 100 um gold electrodes You see only small artifacts on the channels 21 and 22 with tracks next to the stimulating electrode 33 The blanking performance when using the silver pellet as a ground was reproducible However with the internal reference electrode there could sometimes be observed an artifact with very slow kinetics If you observe such problems please try out a silver pellet for grounding the bath 37 5 8 MEA Amplifier with Blanking Circuit for Upright Microscopes User Manual Service and Maintenance You should clean the contact pins of the amplifier with a soft tissue and pure 100 96 alcohol from time to time especially if you have problems with the noise level It may be necessary after a longer time of operation to replace the contact pins Replace gold connectors each year or if ther
44. plication of a few pulses This is generally not a problem as stimulation in regular intervals is the standard case for MEA experiments but should be considered when testing out your experimental settings E Triggered Data a 2307 403sec XAxis 500 gt ms gt 400 404th sweep YAxis 20 gt 200 2 0 Fig 1 Repeated bipolar biphasic voltage stimulation on electrodes 74 and 75 The figure illustrates a stimulation with biphasic pulses at a 50 ms interval 200 mV stimulus amplitude 60 us duration 3D MEA filled with PBS silver pellet as bath electrode The non stimulating electrodes show an excellent behavior without stimulus artifacts 33 MEA Amplifier with Blanking Circuit for Upright Microscopes User Manual imi Triggered Data A iO xl 2338501sec XAws 500 gt ms gt 100 20 0 408th sweep Ys 20 V gt 200 J 2 0 0 0 0 e 0 Li amp 7 2 E i Jn BER HN HE HHHM BRELRBIETE Perret penes enjeu nitent Pere ed M eo rte Pee lal Aa AA M perm tn Pew eet to oe MM en A ELEM M OMM Fig 2 Single shot bipolar biphasic voltage stimulation on electrodes 74 and 75 The figure illustrates a stimulation with single biphasic pulses The experimental settings are identical to the preceding figure The stimulus artifact performance is not so good as with the repeated stimulation Behavior of stimulating electrodes
45. r that is blue for stimulus A and red for stimulus B 21 31 41 51 61 71 A2 22 32 2 52 ez 72 82 43 23 gag 43 63 63 73 831 14 24 34 44 54 64 74 84 A8 25 ss 45 55 65 75 85 16 ze L ILIL se 7s 26 17 27 37 47 57 67 77 e 28 e 48 58 ee ze All Click Download to download this information on the MEA amplifier Start the stimulus generator The stimuli are sent to the selected stimulating electrodes You see stimulus artifacts on all channels The display operates now in a triggered mode so that the stimuli appear aligned to the trigger event E Stimulus A on 53 and B on 33 without Blanking OF x 42984sec XAxis 500 p ms gt 190 690 M Peak 43rdsweep YAxis 100 u gt 1000 J 3 1000 19 MEA Amplifier with Blanking Circuit for Upright Microscopes User Manual Stimulation with blanking Select the Blanking in the MEA Select program Blanking v Blanking The Sync Out signal of the stimulus generator triggers not only the stimulation but the blanking as well E Stimulus A on 53 and B on 33 with Blanking wait 200 102628sec XAws 500 ms gt 400 E 102nd sweep YAxis 100 wV gt 1000 J You see that there are no stimulus artifacts visible on almost all non stimulating electrodes with some residual artifacts on the neighbor electrodes of the stimulating el
46. r amplifier does not get saturated by the stimulus artifact When the blanking signal has stopped the channel output follows the input signal again With the MEA_Select program it is easy to change the electrode selection during the experiment for example to use stimulating electrodes for recording and vice versa You can also ground unwanted or bad electrodes by mouse click It is very convenient to use a stimulus generator and MC_Stimulus to set up both your stimuli and the blanking signal You can then use the digital Sync Out output channel for controlling the blanking of the MEA preamplifier and triggering the recording with the MC_Card 3 2 First Use of the MEA Amplifier Installing the Software System requirements Software One of the following Windows operating systems is required Windows 2000 or Windows XP English and German versions supported Other language versions may lead to software errors Hardware Free RS232 port Installing the software Please check the system requirements before you install the software MCS cannot guarantee that the software works properly if these requirements are not fulfilled Important Please make sure that you are logged in as an administrator before installation Otherwise is possible that the installed software does not work properly Double click Setup exe on the installation volume The installation assistant will show up and guide you through the installation procedure Follow
47. s especially likely if you have upgraded your MEA System from the standard amplifier to the MEA amplifier with blanking circuit or if you use a custom power supply This generation of amplifiers needs an upgraded version of the isolated power supply IPS10W Contact your local retailer describe the problem and your hardware configuration and ask for a power supply that is suitable for your amplifier 41 MEA Amplifier with Blanking Circuit for Upright Microscopes User Manual 6 6 Unpredictable Noise and Artifacts You use the amplifier for stimulation and you see unpredictable noise and or artifacts on single or all channels E Triggered Data E 271430sec XAxis 500 gt ns gt 100 H 200 43th sweep YAxis 100 u gt 1000 1000 0 0 nll T ol CE aua hal eta ieee eS a e p 311 484sec XAxis 500 p ms gt 400 Jp 5 200 121st sweep Y Axis 1000 j uV 10000 10000 Fig 9 Current driven stimulation 100 pA electrode 33 on 10 um TIN electrodes Due to the higher electrode impedance the maximum input voltage of the MEA1060 BC amplifier is exceeded when applying a 100 uA pulse and a proper operation is not possible 42 Troubleshooting Possible causes You use voltage stimuli with a higher amplitude than 5 V Multi Channel Systems recommends not to exceed the maximum recommended stimulus input range of 5 V see Technical Specifica
48. s to connect the MEA amplifier Port COMI v Test Conn Send Blanking FAILED Possible causes The wrong serial port is selected in the MEA_Select program The MEA amplifier is connected to another port Check to which COM port the MEA amplifier is currently connected and select the appropriate port in the program The MEA amplifier is not connected properly to the computer Check the cables and all connections Make sure all connectors fit tightly Noise on Single Electrodes The noise level on single electrodes is significantly higher than 8 pV Possible causes The electrode or the contact pin of the amplifier may be defective To test this do the following Open the amplifier and turn the MEA by 90 degrees Close the amplifier again and start the recording If the same electrode in the MEA layout is affected the amplifier s contact is not ok If another electrode is now affected and the previously affected electrode is ok now the MEA electrode is not ok but the amplifier is fine OR Use the model test probe to test the amplifier 39 6 4 MEA Amplifier with Blanking Circuit for Upright Microscopes User Manual MEA electrode is defective See also the MEA User Manual Possible causes The contact pads are contaminated Clean the contact pads carefully with a swab and pure 100 96 alcohol The contact pads or the electrodes are damaged Use a new MEA Try to handle and clean the MEA m
49. selected stimulating electrodes and all MEA electrodes are disconnected from the amplifier The last signal value on all electrode channels before the blanking pulse is applied will be saved and then kept until the channels are reconnected to the amplifier Switch positions during recording and stimulation Stimulus input Closed for stimulating electrodes 4 TIL during stimulation software controls Open for all electrodes during stimulation 9 E Stimulus Artifact Suppression Blanking Data acquisition Electrode A TTL pulse blanking signal that has to be timed exactly with the stimulus pulse triggers both the stimulation and the blanking During the blanking signal both stimulus inputs are connected to the software selected stimulating electrodes A and B and all MEA electrodes are disconnected from the amplifier The last signal value on all electrode channels before the blanking pulse will be saved and then kept until the channels are reconnected to the amplifier This avoids that the amplifier gets saturated on all channels during stimulation which is the case with standard amplifiers You can disable the blanking for test purposes The stimulus artifact suppression performance depends mainly on the electrical state of the electrode that is the residual net charge of the electrode This depends on the stimulus type current or voltage driven biphasic or monophasic strength of the stimulus amplitude dura
50. ssssssss 23 Software Installing cte 9 Stimulation daenna anai 30 T Temperature connecting the Temperature Controller eade 9 Temperature control 25 Test Connection sususs 15 Triggering blanking ieena 15 31 ME Rakona a 15 stimulation aenneren 15 TTL blanking signal usus 31 WwW Wait co etit eed 15 31
51. sulting in artifacts or in a saturation of the amplifier 17 000 sec Mates 10 4 me ij io fal Wee YA fS p of moh w Bj p mo n j n t 6 m w s 2 5 m e m mo mno rm3235 5 mp os m d i a LLL Ls j E j j woo Peak Detection mo r n S J Y wy no ute gh W ye La f pM AX Aaa A A i e vj LP NI Medie m i e me uM cct Ned inne m A id es A ar het EE z Al jp x arama mA mer Wem 222 x odii dc al MR wm mem m dae 3 ar J vue P is anat ern 4 Wry Mua an ey INI A iei Possible causes The cable connecting the amplifier to the power supply that is the MCS High Grade cable leading from the amplifier to the data acquisition computer if you have an MEA System is too long The applied voltage is not high enough for operating the amplifier Use a shorter cable if possible or try another power supply with a higher output power MCS High Grade cables with a total length of up to 3 m and the isolated power supply IPS10W are recommended for the MEA System You have connected too many amplifiers to your power supply The isolated power supply IPS10W that is integrated in your data acquisition computer if you use an MEA System can supply power for up to two MEA amplifiers with blanking circuit Use an additional power supply for operating the amplifiers or reduce the number of amplifiers The supply power is too low for operating the amplifier This i
52. tandard total bandwidth MEA1060 Up BC and standard FA60S BC 10 Hz to 3000 Hz 53 Standard total gain MEA1060 Up BC and standard FA60S BC 1100 Inverse microscopes 3 5mm 7 1 3 FA60S BC Operating temperature Storage temperature Dimensions W x D x H Weight Supply voltage external power supply Supply current Number of analog input channels Input voltage Input impedance Input noise Noise density Number of analog output channels Output voltage Output current Output impedance Bandwidth Gain Appendix 10 C to 50 C 0 C to 50 C 92 mm x 145 mm x 26 mm 450g 6 5Vto 9VDC 200 mA 60 500 mV with respect to 5 V supply voltage gt 10 O parallel to 10 pF 1 uV RMS full bandwidth inputs short circuited e Onl 4 Hz 60 5V 10 mA 300 Q 8 Hz to 3000 Hz standard 1 Hz to 5000 Hz custom 20 standard 10 to 100 custom Standard total gain MEA1060 1BC and standard FA60S BC 1100 49 7 1 4 MEA Amplifier with Blanking Circuit for Upright Microscopes User Manual Heating Element The heating element is mounted onto the bottom side of the base plate of the MEA1060 amplifier It is used for keeping the temperature in the MEA culture chamber stable during recordings Input voltage max 10 V Input current max2A Temperature sensor PT 100 Resistance 15x20 Heating temperature Ambient temperature min 10 C to 50 C Accuracy 0 1 C in the range of 20 C to 40 C
53. the instructions of the installation assistant Setting Up and Connecting the MEA Amplifier Warning Spilled liquid can damage or even completely destroy the electronics of the MEA amplifier Please be extremely 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 Note The housing of the MEA amplifiers was optimized for Zeiss Axiovert microscopes MEA Amplifiers are compatible to most standard microscopes if the following prerequisites are met This MEA amplifier type has been developed for standard upright microscopes with a rectangular microscope table The focal plane of the microscope has to be in a distance of 8 mm to the microscope table Note If you use a complete MEA System the MEA amplifier will usually be powered by the isolated power supply IPS10W that is integrated into the data acquisition computer The power is distributed along the MCS 68 Pin High Grade Cable If you use your MEA amplifiers together with an MEA Switch or if you use a custom data acquisition system without IPS10W you will need an external power supply for operating the amplifier s Please ask your local retailer for more information on setup options Connect the MEA preamplifier with blanking circuit to the filter amplifier s input with a 68 pin MCS standard cable Connect the filter amplifier s output to the
54. this is not considered a useful mode of operation because the amplifier will get saturated by the high stimulus input without blanking Important The input voltage of the MEA1060 BC amplifier is limited to 5 V Exceeding the voltage input range can result in unpredictable noise and artifacts In rare cases even damage to the amplifier electronics might occur For current driven stimulation the voltage amplitude depends on the electrode impedance As the electrode impedance depends on several parameters for example the electrode s degree of wear and its hydrophilicity and therefore cannot be predicted it is generally recommended to use only voltage driven stimulation Current driven stimulation may work with larger 30 um TiN electrodes that have a low impedance but this cannot be guaranteed by the manufacturer For more information on the setup please see the chapter Setting Up and Connecting the MEA Amplifier Under Stimulation select a stimulus input Stim A or Stim B and click any buttons on the button array in the MEA layout Blue electrodes are selected for stimulus A and red electrodes are selected for stimulus B asi e sien zi 12 22 se e se 62 721 221 as zs 33 43 531 63 mi es 14 24 se 44 54 64 7 as 251 ss 36 ze 36 Fur 2 36 Click Download to apply the settings 30 5 6 Operating the MEA Amplifier During the blanking signal the stimulus inputs are connected to the software
55. tion and frequency on the electrode type and size and other parameters and has to be determined empirically Complete artifact suppression may not always be possible depending on those parameters Generally the stimulus artifact suppression performance is much better when using voltage driven stimulation than current driven stimulation In the following you will find some general recommendations for an improved stimulus artifact performance but please understand that it is not possible for us to discuss all possible variations in this document Timing and duration of blanking signal For most applications MCS considers a delay in the range of 100 ys suitable for discharging the electrode and recommends a minimum blanking pulse that starts with the stimulus and stops 100 ps after the stimulus The fact that the digital output of the stimulus generator from MCS is about 20 ps faster than the analog output ensures that the blanking signal is delivered before the stimulus If you use a pulse generator from a supplier other than MCS you may have to use other trigger settings It is very important that the blanking pulse is delivered slightly before the stimulus For improving the blanking performance you can try to extend the blanking pulse after the end of the stimulus pulse This gives the electrodes a longer time to discharge before they are disconnected from the stimulus inputs The charge carrier cannot flow back to the STG after the end of t
56. tions under Appendix Please adjust the amplitude of the stimuli used You use current driven stimulation and you have started the stimulation before selecting a stimulating electrode in MEA Select In this case the stimulus generator sends the current into the open circuit of the amplifier This is not an allowed operation Always start the stimulus generator after having selected a stimulating electrode in MEA Select Make sure you have selected the appropriate stimulus input and downloaded the information onto the amplifier You use current stimuli and electrodes with a smaller diameter than 30 um or older electrodes with a higher impedance Multi Channel Systems recommends not to exceed the maximum recommended stimulus input range of 5 V see Technical Specifications under Appendix To avoid this the stimulation with current is generally not recommended especially not with electrodes that have a high impedance The impedance of electrodes with a lower diameter or the impedance of older deteriorated electrodes is considerably higher resulting in a high voltage exceeding the input range MCS recommends to use voltage stimuli with an amplitude in the recommended stimulus input range to be on the safe side For more information on stimulation via MEA electrodes see also the MEA User Manual Liquid Spilled onto Amplifier Warning Spilled liquid can damage or even completely destroy the electronics of the MEA amplifier Avoid it
57. uration ajseiseni Cem ame g se FEE A ana a 1 aaf g3 33 431 53 esiti es as mw once Download ine 15 25 sess ss es 25 o peveiond range ea rf bat com ee eS 17 1g7 37 47 57 67 97 Values are rounded TETTE I o Port con Test Conn to m tiples of 20 ps a s LA Click any buttons Connection to User defined delay to select electrodes MEA amplifier between end of sti for recording stimu mulation and start lating or connecting of recording to ground With the MEA preamplifier with blanking circuit software controls allow you to select any electrode on an MEA for stimulation and recording You can apply two different stimulus protocols to any selection of electrodes A blanking signal TTL pulse transiently switches off the input stage of the amplifiers during the stimulus thus avoiding the stimulus artifacts on non stimulating electrodes Amplifier saturation is effectively prevented and the recovery time is greatly reduced It is also possible to record from stimulating electrode shortly after stimulation Without blanking technology recovery time depends on the filter amplifier type It is roughly the time constant of the high pass filter multiplied by ten During this time the data output is distorted With the blanking circuit the voltage outputs of the preamplifier are held constant during the time when the blanking input is active Thus the following filte
58. us input A or B of the MEA amplifier If you use two separate stimulation patterns connect channel 1 of the stimulus generator to stimulus input A and channel 2 to stimulus input B and the corresponding ground for each channel to the ground inputs labeled G of the MEA amplifier Standard setup for monopolar stimulation in voltage mode Stimulus generator outputs MEA amplifier inputs C2 G2 The next illustration shows a standard setup for dipolar stimulation In this case you connect the U outputs to either stimulus input A or B of the MEA amplifier The U output of the same channel is connected to the other input The ground output of the same channel is connected to either ground input labeled G of the amplifier It does not matter which ground input you use because both G inputs are internally connected Usually you will then select two neighboring electrodes on the MEA for the dipolar stimulation for example electrode 33 for stimulus A and electrode 34 for stimulus B For more information on the stimulus generator output signals please see the Stimulus Generator User Manual Standard setup for dipolar stimulation in voltage mode Stimulus generator outputs MEA amplifier inputs OOG e 11 4 1 4 2 First Tests and Tutorial First Tests and Tutorial First Functional Tests Each MEA amplifier has been thoroughly tested at the factory site before delivery However you may want to perform some tests yourse
59. utorial General Performance Noise Level and Operating the MEA Amplifier Mounting the MEA Probe Temperature Control The biological sample is cultured directly on the MEA You can record without needing an incubator because a heating element is integrated into the amplifier and the perfusion cannula and are both controlled by a Temperature Controller Temperature Controller and perfusion cannula with heating element and sensor are either included in the MEA System or can be ordered separately You have several options regarding the culture chamber such as a semipermeable seal that guarantees stable environmental conditions For using the integrated heating element of the MEA amplifier connect it with the black cable to the Temperature Controller The heating is active but the cooling is passive Therefore the minimum temperature is limited by the room temperature Please refer to the Temperature Controller User Manual for more information Important Please make sure that you have selected the appropriate PID coefficients for the amplifier type for inverted or upright microscopes in use 25 MEA Amplifier with Blanking Circuit for Upright Microscopes User Manual Mounting the MEA Probe and Grounding the Bath Warning Do not use too much force Otherwise you could damage the delicate MEA or contact pins of the amplifier Important Click Change MEA in the MEA Select program before you remove the shielding or open the amplifier
60. ve satisfying results with the plain silver wire try an Ag AgCl electrode If you use MEAs with internal reference electrode you can use the reference electrode for grounding the bath This has the advantage that you can keep the culture chamber closed and sterile for example with MEA MEM semipermeable membranes Important If you use an MEA with internal reference electrode you have to connect pin 15 to ground with the provided cable Setting electrode 15 to ground in the MEA Select program is not sufficient for grounding the bath Attach the provided silver wire or pellet to the amplifier s ground and place it into the bath near the rim of the culture chamber If you use an MEA with internal reference electrode connect the ground to the reference electrode socket pin 15 with the provided connector Make sure that the orientation of the MEA inside the amplifier is appropriate Replace the shielding Make sure the setup is complete Click Change MEA again to reconnect the electrodes to the amplifier s input stage Wait until the amplifier has recovered and you see the standard noise level on all channels before starting your experiment The recovery time depends on the electrodes used and usually takes about 1 or 2 minutes 27 MEA Amplifier with Blanking Circuit for Upright Microscopes User Manual 5 4 Grounding Defective Electrodes You can ground defective electrodes with the MEA_Select program In the following example

MEA Amplifier with Blanking Circuit for Upright Microscopes

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