Axon AutoMate Scientific MultiClamp 700B User manual

MultiClamp 700B
COMPUTER-CONTROLLED
MICROELECTRODE AMPLIFIER
Theory and Operation
Part Number 2500-0157 Rev D March 2005 Printed in USA
Copyright 2005 Axon Instruments / Molecular Devices Corp.
No part of this manual may be reproduced, stored in a retrieval system, or
transmitted, in any form or by any means, electronic, mechanical, photocopying,
microfilming, recording, or otherwise, without written permission from Molecular
Devices Corp.
QUESTIONS? See Axon's Knowledge Base: http://support. .comaxon
800.998.MATE | www.autom8.com | 650 University Ave # 5, Berkeley, CA 94710 USAt e l 5 1 0 . 8 4 5 . 6 2 8 3 | f a x 5 1 0 . 6 6 5 . 3 9 7 5 | e - m a i l i n f o @ a u t o m 8 . c o m

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P LEASE READ !!!!! SAFETY
There are important safety issues that you must take into account when using this
instrument. Please carefully read the safety warnings starting on page 159 before
you use this instrument.
VERIFICATION
This instrument is extensively tested and thoroughly calibrated before leaving the
factory. Nevertheless, researchers should independently verify the basic accuracy
of the controls using resistor/capacitor models of their electrodes and cell
membranes.
WARNING
If this equipment is used in a manner not specified by the manufacturer, the
protection provided by the equipment may be impaired.
DISCLAIMER
This equipment is not intended to be used, and should not be used, in human
experimentation or applied to humans in any way.
Verification, Warning, Disclaimer

Table of Contents •iii
Table of Contents
Chapter 1 Introduction .......................................................................................... 1
Chapter 2 Installation and Basic Operation ........................................................ 3
Installation............................................................................................................. 3
Check List ......................................................................................................... 3
Installing Hardware ........................................................................................... 4
Installing the MultiClamp 700B Commander................................................... 4
Functional Checkout ............................................................................................. 6
Communication with the MultiClamp 700B..................................................... 6
Setting Parameters in the MultiClamp 700B Commander ................................ 7
Toolbar Buttons in the MultiClamp 700B Commander.................................... 9
Test the Noise.................................................................................................. 10
Calibration....................................................................................................... 11
Getting Help in the MultiClamp 700B Commander ....................................... 13
Chapter 3 Tutorials.............................................................................................. 15
Check List ........................................................................................................... 15
Model Cell....................................................................................................... 16
Tutorial 1 – Electrode in the Bath: Voltage Clamp............................................. 17
Tutorial 2 – Electrode in the Bath: Current Clamp ............................................. 19
Tutorial 3 – Giga Seal Configuration.................................................................. 21
Tutorial 4 – Whole-Cell Configuration: Voltage Clamp..................................... 26
Tutorial 5 – Whole-Cell Configuration: Current Clamp ..................................... 31
Tutorial 6 – Whole-Cell Configuration: Automatic Mode Switching................. 37
Table of Contents

iv •Table of Contents
Chapter 4 Guide to Electrophysiological Recording......................................... 43
General Advice.................................................................................................... 44
Chamber Design .............................................................................................. 44
Perfusion.......................................................................................................... 44
Mechanical Stability........................................................................................ 44
Optics .............................................................................................................. 45
Bath Electrode ................................................................................................. 45
Interfacing a Computer.................................................................................... 46
Computer Noise............................................................................................... 47
Patch Clamping ................................................................................................... 47
Headstage and Holder Considerations............................................................. 47
Forming a Gigaseal ......................................................................................... 49
Whole-cell Voltage Clamp Recording ............................................................ 51
Perforated-patch Recording............................................................................. 54
Low Noise Techniques.................................................................................... 55
Sharp Microelectrode Recording......................................................................... 59
Sharp Microelectrode or Patch Electrode? ...................................................... 60
Microelectrode Properties ............................................................................... 60
Filling Solutions .............................................................................................. 64
Impaling Cells ................................................................................................. 64
Chapter 5 Reference Section ............................................................................... 67
Audio Monitor..................................................................................................... 68
Bath Headstage and Electrodes ........................................................................... 72
R
b
Minimization .............................................................................................. 72
Use of a Bath Headstage ................................................................................. 74
Bridge Balance .................................................................................................... 75
Bridge Balance in the Bath.............................................................................. 76
Bridge Balance in the Cell............................................................................... 77
Buzz..................................................................................................................... 78
Capacitance Compensation ................................................................................. 78
Electrode Capacitance Compensation ............................................................. 79
Whole-Cell Capacitance Compensation.......................................................... 80
MultiClamp 700B Theory and Operation, Copyright 2005 Axon Instruments / Molecular Devices

Table of Contents •v
Auto Button..................................................................................................... 83
Manual Adjustment of Capacitance Compensation ........................................ 83
Filtering the Command Stimulus .................................................................... 84
Capacitance Neutralization ................................................................................. 84
Input Capacitance............................................................................................ 84
Adjusting Capacitance Neutralization............................................................. 86
Limitations of Capacitance Neutralization...................................................... 86
Clear .................................................................................................................... 87
Electrochemistry.................................................................................................. 87
External Command Inputs................................................................................... 89
External Command Sensitivity........................................................................ 89
Additivity of Commands................................................................................. 90
Command Filter Frequency............................................................................. 90
Feedback Resistor ............................................................................................... 91
V-Clamp Mode................................................................................................ 91
I-Clamp Mode ................................................................................................. 93
Filters................................................................................................................... 93
-3 dB Frequency.............................................................................................. 94
Types of Filters ................................................................................................... 95
Bessel Filter..................................................................................................... 95
Butterworth Filter............................................................................................ 95
Choosing the Cutoff Frequency ...................................................................... 95
High-pass Filter............................................................................................... 97
Command Filter Frequency............................................................................. 97
Grounding and Hum............................................................................................ 97
Headstage ............................................................................................................ 98
Voltage Clamp Circuit .................................................................................... 99
Current Clamp Circuit................................................................................... 101
Mounting the Headstage................................................................................ 102
Bath Connection............................................................................................ 102
Cleaning ........................................................................................................ 102
Static Precautions .......................................................................................... 102
Acoustic Pick-up ........................................................................................... 102
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vi •Table of Contents
Help ................................................................................................................... 103
Holders .............................................................................................................. 103
Holder Design ............................................................................................... 103
Optional Ag/AgCl Pellets.............................................................................. 105
Holder Use..................................................................................................... 105
Holder Maintenance ...................................................................................... 107
Adapters ........................................................................................................ 107
Input/Output Connections ................................................................................. 107
Front Panel .................................................................................................... 107
Rear Panel ..................................................................................................... 109
Leak Subtraction................................................................................................ 110
Mode.................................................................................................................. 111
Model Cell......................................................................................................... 112
Noise.................................................................................................................. 113
Noise.................................................................................................................. 114
Measurement of Noise................................................................................... 114
Sources of Noise............................................................................................ 114
Oscilloscope Triggering .................................................................................... 116
Output Zero ....................................................................................................... 117
Overload ............................................................................................................ 118
Polarity Conventions ......................................................................................... 118
Biological Polarity Conventions ................................................................... 118
MultiClamp Polarity Conventions................................................................. 119
Polarity Summary for Different Recording Configurations.......................... 120
Power Supply .................................................................................................... 120
Supply Voltage Selection .............................................................................. 121
Changing the Fuse......................................................................................... 121
Glitches.......................................................................................................... 121
Select Device..................................................................................................... 122
Series Resistance Compensation ....................................................................... 122
Introduction to R
s
Compensation .................................................................. 122
Is R
s
Compensation Necessary? .................................................................... 124
Adjusting R
s
Compensation .......................................................................... 125
MultiClamp 700B Theory and Operation, Copyright 2005 Axon Instruments / Molecular Devices

Table of Contents •vii
Theory of R
s
Compensation .......................................................................... 129
The ‘Prediction’ Control ............................................................................... 130
The ‘Prediction’ Control ............................................................................... 131
Saturation Effects .......................................................................................... 132
Readjustment of Whole Cell Compensation with ‘Prediction’ ..................... 133
The ‘Correction’ Control............................................................................... 134
Readjustment of Whole Cell Compensation with ‘Correction’ .................... 135
Setting ‘Prediction’ and ‘Correction’ Values................................................ 135
Oscillations.................................................................................................... 135
Limitations of R
s
Compensation ................................................................... 136
SoftPanel Configuration.................................................................................... 137
Status ................................................................................................................. 138
Zap..................................................................................................................... 138
Chapter 6 Troubleshooting................................................................................ 139
Chapter 7 Specifications .................................................................................... 141
References ............................................................................................................ 147
Technical Assistance............................................................................................ 149
Warranty and Repair Service ............................................................................ 151
Circuit Diagrams Request Form........................................................................ 155
Declaration of Conformity.................................................................................. 157
Important Safety Information............................................................................ 159
Index ..................................................................................................................... 163
Table of Contents