Axon Axopatch 200B User manual

Axopatch 200B, Copyright 1997-1999, Axon Instruments, Inc.
March 1999
Axopatch 200B
Patch Clamp
Theory and Operation
Part Number 2500-121 Rev D, Printed in U.S.A.
Copyright 1997-1999 Axon Instruments, Inc.
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 Axon Instruments, Inc.
QUESTIONS? Call [phone]

IMPORTANT INFORMATION
Axopatch 200B, Copyright 1997-1999, Axon Instruments, Inc.
Disclaimer
THIS EQUIPMENT IS NOT INTENDED
TO BE USED AND SHOULD NOT BE
USED IN HUMAN EXPERIMENTATION
OR APPLIED TO HUMANS IN ANY
WAY.
Warning
IF THIS EQUIPMENT IS USED IN A
MANNER NOT SPECIFIED BY THE
MANUFACTURER, THE PROTECTION
PROVIDED BY THE EQUIPMENT MAY
BE IMPAIRED.
Power-Supply Voltage Selection and
Fuse Changing
Supply Voltage
The Axopatch 200B can be directly
connected to all international supply
voltages. The input range is from 100 to
240 V~. No range switching is required.
Changing the Fuse
The Axopatch 200B uses a 250 V~, T2A,
5 x 20 mm fuse.
In the event of fuse failure, disconnect
the power cord.
Before changing the fuse investigate the
reason for its failure.
To change the fuse:
1. Disconnect the power cord.
2. Use a screwdriver or a similar device
to rotate the fuse holder
counterclockwise.
3. Replace the fuse with another fuse
of the same rating.
4. Reconnect the power cord.
Basic Equipment Setup and Safety
1. Supply and Earthing
Connections: Use the included IEC
power cord to connect the
instrument to a GROUNDED
power receptacle.
2. Mounting: Table or rack.
3. Assembly: The headstage connects
to the instrument through the rear
panel, 15 pin D-sub connector
marked "headstage".
4. Use: Do not operate this equipment
with covers or panels removed.
5. Cleaning: Wipe the headstage
connector with a damp cloth to
clean salt spills. Avoid spilling
liquids on the headstage.
The Teflon input connector should
be kept very clean. Effective
cleaning can be done by spraying
with alcohol or swabbing carefully
with deionized water. If possible,
avoid the use of Freon since it is
thought to be detrimental to the
environment.
Safe Environmental Conditions
1. Indoor use.
2. Mains supply fluctuations: not to
exceed ±10% of the nominal
voltage.
3. Temperature: between 5 ºC and
40 ºC.
4. Altitude: up to 2000 m
5. This instrument is designed to be
used under laboratory conditions.
Operate in a clean, dry
environment only. Do not operate
in a wet or damp environment.
Static Precautions
The headstage can normally be safely
handled. However, if you are in a
laboratory where static is high (i.e., you
hear and feel crackles when you touch
things), you should touch a grounded
metal object immediately before touching
the headstage.
You should not switch off power to the
Axopatch 200B when handling the
headstage input since this will upset the
thermal equilibrium.
WARNING
Shipping the Axopatch 200B
The Axopatch 200B is a solidly built
instrument designed to survive shipping
around the world. However, in order to
avoid damage during shipping, the
Axopatch 200B must be properly
packaged.
In general, the best way to package the
Axopatch 200B is in the original factory
carton. If this is no longer available, we
recommend that you carefully wrap the
Axopatch 200B in at least three inches
(75 mm) of foam or "bubble-pack"
sheeting. The wrapped Axopatch 200B
should then be placed in a sturdy
cardboard carton. Mark the outside of
the box with the word FRAGILE and an
arrow showing which way is up.
We do not recommend using loose foam
pellets to protect the
Axopatch 200B. If the carton is dropped
by the shipper, there is a good chance
that the Axopatch 200B will shift within
the loose pellet packaging and be
damaged.
If you need to ship your Axopatch 200B
to another location, or back to the
factory, and you do not have a means to
adequately package it, Axon Instruments
can ship the proper packaging material
to you for a small fee. This may seem
like an expense you would like to avoid,
but it is inexpensive compared to the cost
of repairing an instrument that has
sustained shipping damage.
It is your responsibility to package the
instrument properly before shipping. If it
is not, and it is damaged, the shipper will
not honor your claim for compensation.

RENSEIGNMENTS IMPORTANTS
Axopatch 200B, Copyright March 1997-1999, Axon Instruments, Inc.
LIMITE DE RESPONSABILITE
CE MATERIEL N'A PAS ETE CONCU
POUR DES EXPERIENCES SUR LES
ETRES HUMAINS; ET NE DOIT DONC
PAS ETRE UTILISE A CETTE FIN.
ATTENTION
L'EMPLOI DE CE MATERIEL D'UNE
MANIERE DIFFERENTE A CELLE
SPECIFIEE PAR LE FABRICANT
AFFECTERA LE NIVEAU DE
PROTECTION FOURNIT PAR
L'APPAREIL.
Sélection du voltage et changement
du fusible
Voltage d'alimentation
L'Axopatch 200B peut être directement
branché sur toutes alimentations
comprises entre 100 et 240 V~. Aucun
changement n'est nécessaire afin de
sélectioner le voltage de l’appareil.
Changement du fusible
L'Axopatch 200B emploie un fusible de
250 V~, T2A, 5 ×20 mm.
En cas de rupture du fusible, débrancher
la prise de courant.
Avant de changer le fusible, chercher la
raison de la panne.
Pour changer le fusible:
1. Débrancher la prise de courant.
2. A l'aide d'un tournevis ou autre outil
de ce genre, faire tourner le support
du fusible dans de sens opposé des
aiguilles d'une montre.
3. Remplacer le fusible par un fusible
de même valeur.
4. Rebrancher la prise de courant.
Installation du matériel et sécurité
1. Branchement: Employer le fil
electrique IEC fourni pour brancher
l'appareil a une prise de courant
comprenant UNE TERRE.
2. Pose: Table ou rack.
3. Montage: La tête de l'amplificateur
(“headstage”) est connectée à
l'appareil sur le panneau arrière, par
l'intermediere d'une prise D-sub à
15 fiches portant l'indication
“headstage”.
4. Emploi: Ne pas utiliser ce matériel
sans son couvercle et ne pas le
couvrir lors de son utilisation.
5. Nettoyage: Essuyer la prise du
“headstage” avec un linge humide
pour nettoyer les traces de sel.
Eviter de renverser des liquides sur
le “headstage”.
La prise d'entrée en Téflon doit être
maintenue trés propre. Un
nettoyage efficace consiste à
vaporiser de l'alcool ou á essuyer
soigneusement avec de l'eau
désionisée. Si possible, éviter
l'emploi de Fréon, ce produit étant
considéré comme nuisible pour
l'environnement.
Conditions à respecter pour un
emploi sans danger
1. Emploi à l'intérieur.
2. Fluctuations du réseaux
d'alimentation: ne doivent pas
dépasser ±10% de la tension
nominale.
3. Température: entre 5 °C et 40 °C.
4. Altitude: jusqu'à 2000 m.
5. Cet appareil a été étudié pour l'emploi
en laboratoire et il doit être situé dans
un environnement sec et propre. Ne
pas l'utiliser dans un environnement
mouillé ou humide.
Précautions statiques
Le “headstage” peut être maniée sans
danger. Cependant, dans un laboratoire
avec un niveau élevé d'electricité
statique (c'est-à-dire lorsque vous sentez
et voyez des décharges électriques),
touchez un objet métallique pour une
mise à la terre avant de toucher le
“headstage”.
Ne pas d'ébrancher l'Axopatch 200B lors
de la manipulation de l'entrée du
“headstage”, ceci risque de déranger son
équilibre thermique.
ATTENTION
Expédition de l'Axopatch 200B
L'Axopatch 200B est un appareil de
construction robuste, étudié en vue
d'expéditions dans le monde entier.
Cependant, l'appareil doit être
correctement emballé pour éviter tout
domage pendant son transport.
En général, la meilleure façon d'emballer
l'Axopatch 200B est de le mettre dans
son carton d'origine. Si celui-ci n'est plus
disponible, il est recommandé
d'envelopper soigneusement l'Axopatch
200B dans au moins trois inches (75
mm) de mousse ou de feuilles
d'emballage à bulles. L'Axopatch 200B
ainsi protégé devra alors être placé dans
un carton solide. Indiquer la mention
FRAGILE sur l'extérieur de la boîte ainsi
qu'une flèche vers le haut montrant la
position verticale.
Il n'est pas recommandé d'employer des
boulettes de mousse pour protéger
l'Axopatch 200B. En cas de chute de la
boîte durant son transport, l'Axopatch
200B pourrait se déplacer à l'intérieur et
être endommagé.
Si vous devez expédier l'Axopatch 200B
à un autre endroit, ou le renvoyer au
fabricant, et si les matériaux d'emballage
nécessaires corrects ne sont pas
disponibles, ces derniers peuvent être
obtenus chez Axon Instruments pour un
prix minime. Bien que ceci puisse
sembler être une dépense que vous
pourriez éviter, elle est cepandant
insignifiante en comparaison à celle que
coûterait la réparation d'un appareil
endommagé pendant le transport.
La responsabilité vous incombe de bien
emballer l'appareil avant son expédition.
Si ceci n'est pas fait, le transporteur ne
pourra pas satisfaire vos réclamation de
compensation en cas d'avaries.

WICHTIGE INFORMATIONEN
Axopatch 200B, Copyright 1997-1999, Axon Instruments, Inc.
UNZULÄSSIGE VERWENDUNG
DIESER APPARAT IST NICHT
VORGESEHEN, BEI MENSCHLICHEN
VERSUCHEN VERWENDET ZU
WERDEN UND AUCH NICHT AN
MENSCHEN IN IRGENDEINERWEISE
ANWENDBAR.
WARNUNG
WEN DIESER APPARAT IN EINER ART
UND WEISE ANGEWENDET WIRD, DIE
NICHT VOM HERSTELLER SPEZIFISCH
ERWÄHNT WIRD, KANN DIE
SCHUTZVORRICHTUNG DES
APPARATES BEEINTRÄCHTIGT
WERDEN.
Spannungswahl für die
Stromversorgung und Auswechseln
der Sicherung
Netzspannung
Der Axopatch 200B kann direkt an alle
internationalen Netzspannungen
angeschlossen werden. Die
Eingangsspannung reicht von 100 bis
240 V~. Ein Umschalten des
Spannungsbereichs ist nicht erforderlich.
Auswechseln der Sicherung
Der Axopatch 200B verwendet eine
250V~, T2A, 5 ×20 mm Sicherung.
Im Falle des Ausfalls der Sicherung das
Netzkabel ausschalten.
Vor dem Auswechseln der Sicherung den
Grund für ihren Ausfall untersuchen.
Schritte zum Auswechseln der Sicherung:
1. Das Netzkabel ausschalten.
2. Die Fassung der Sicherung mit einem
Schraubenzieher oder einem
ähnlichen Werkzeug entgegen dem
Uhrzeiger drehen.
3. Die Sicherung mit einer anderen
Sicherung mit gleicher Nennleistung
ersetzen.
4. Das Netzkabel wieder anschließen.
Grundlegende Hinweise zu Installation
und Sicherheit der Ausrüstung
1. Netz- und
Erdungsanschlüsse: Das Instrument mit
dem beigefügten IEC Netzkabel an
einen Erdungsschalter anschließen.
2. Anbringung: Tisch oder Rahmengestell.
3. Montage: Der Vorverstärker
(“headstage”) wird über einen mit der
Aufschrift “headstage”
gekennzeichneten 15 Pin D-
Unterstecker an der Rückwand des
Instrumentes verbunden.
4. Gebrauch: Dieser Apparat darf nicht
mit abgenommenen Abdeckungen oder
Platten in Betrieb gesetzt werden.
5. Reinigung: Zur Reinigung von
verschüttetem Salz den
Vorverstärkeranschluß mit einem
feuchten Tuch abwischen. Das
Verschütten von Flüssigkeiten auf den
“headstage” ist zu vermeiden.
Der Teflon-Eingangsstecker sollte in
sehr sauberem Zustand gehalten
werden. Durch Besprühen mit Alkohol
oder vorsichtigem Abtupfen mit
entionisiertem Wasser ist eine
wirksame Reinigung möglich. Die
Benutzung von Freon ist nach
Möglichkeit zu vermeiden, da diese
Substanz als umweltschädigend
angesehen wird.
Umweltsichere Betriebsbedingungen
1. Verwendung in Innenräumen.
2. Netzschwankungen: darf nicht ±10%
der Nennspannung überschreiten.
3. Temperatur: zwischen 5 °C und 40 °C.
4. Höhe: bis zu 2000 m.
5. Dieses Instrument ist für den Gebrauch
unter Laborbedingungen vorgesehen.
Nur in sauberer, trockener Umgebung
in Betrieb setzen. Nicht in nasser oder
feuchter Umgebung in Betrieb setzen.
Schutzmaßnahmen gegen statische
Aufladung
Der “headstage” kann normalerweise
sicher gehandhabt werden. Falls Sie sich
jedoch in einem Labor mit höher statischer
Aufladung befinden (D.h. Sie hören und
fühlen beim Berühren von Objekten ein
Knacken), sollten Sie unmittelbar vor dem
Berühren der “headstage” ein geerdetes
Objekt aus Metall anfassen.
Bei Handhabung des
Vorverstärkereingangs sollten Sie die
Stromzufuhr zum Axopatch 200B nicht
abschalten, um das
Temperaturgleichgewicht nicht zu stören.
WARNUNG
Versand des Axopatch 200B
Bei dem Axopatch 200B handelt es sich
um ein solide gebautes Instrument, das
beim weltweiten Versand keinen Schaden
nehmen sollte. Um jedoch
Versandschäden zu verhindern, muß der
Axopatch 200B ordnungsgemäß verpackt
werden.
Im allgemeinen läßt sich der Axopatch
200B am besten im Originalkarton des
Werks verpacken. Ist dieser nicht mehr
vorhanden, empfehlen wir, den Axopatch
200B vorsichtig in mindestens 75 mm
starkem Schaumstoff oder
Bubblepackungen einzuwickeln. Der so
eingewickelte Axopatch 200B sollte dann
in einen festen Pappkarton gesetzt
werden. Die Außenseite des Kartons ist
mit dem Worten ZERBRECHLICH
(FRAGILE) und einem Pfeil, der auf die
Oberseite des Kartons weist, zu
kennzeichnen.
Sollte der Karton vom Spediteur
fallengelassen werden, besteht eine gute
Möglichkeit, daß der Axopatch 200B
innerhalt der losen
Schaumstoffkugelverpackung bewegt wird
und dadurch beschädigt werden kann.
Wenn Sie den Axopatch 200B an einen
anderen Ort oder zurück ans Werk senden
müssen und Ihnen kein angemessenes
Verpackungsmaterial zur Verfügung
stehen, kann Axon Instruments Ihnen das
geeignete Verpackungsmaterial gegen
eine kleine Gebühr zustellen. Sie mögen
dies zwar als unnötige Zusatzkosten
betrachten, doch ist dieser Aufwand im
Vergleich zu den Reparaturkosten fur ein
während des Transports beschädigtes
Instrument gering.
Sie sind selbst für das richtige Verpacken
des Instruments vor dem Versand
verantwortlich. Bei einer nicht
ordnungsgemäßen Verpackung, die eine
Beschädigung zur Folge hat, wird der
Spediteur ihren Schadensersatzanspruch
nicht anerkennen.

INFORMACION IMPORTANTE
Axopatch 200B, Copyright March 1997-1999, Axon Instruments, Inc.
LÍMITE DE RESPONSABILIDADES
ESTE EQUIPO NO ESTÁ DISEÑADO
PARA USO EN HUMANOS Y NO DEBE
USARSE PARA EXPERIMENTACIÓN O
APLICACIÓN EN SERES HUMANOS
BAJO NINGUNA CIRCUNSTANCIA.
ADVERTENCIA
SI ESTE EQUIPO SE USA DE MANERA
NO ESPECIFICADA POR EL
FABRICANTE SE PODRÍA PERDER LA
PROTECCIÓN PROVISTA POR EL
EQUIPO.
Selección del suministro de corriente
y cambio de fusibles
Voltaje de entrada
El Axopatch 200B puede conectarse
directamente a todos los suministros de
energía. El límite de voltaje va entre 100
y 240 V~. No es necesario efectuar
cambios en el selector.
Cambio de fusible
El Axopatch 200B utiliza un fusible de
250 V~, T2A, 5 ×20 mm.
En el caso de que un fusible falle,
desconecte el cordón eléctrico.
Antes de cambiar el fusible investigue la
causa de la falla.
Para cambiar el fusible:
1. Desconecte el cordón eléctrico.
2. Use un destornillador o un
dispositivo similar para girar el
portafusibles en sentido contrario al
de las manecillas del reloj.
3. Reemplace el fusible existente con
otro de la misma capacidad.
4. Conecte nuevamente el cordón
eléctrico.
Instalación básica y seguridad del
equipo
1. Suministro de corriente
y conexión a tierra: Use el cordón
eléctrico IEC incluido para conectar
el instrumento a una toma de
corriente CON CONEXIÓN A
TIERRA.
2. Montaje: Sobre una mesa o en un
estante.
3. Ensamblaje: El cabezal
(“headstage”) se conecta al
instrumento en el tablero posterior
con el conector de 15 clavijas D-
sub, marcado “headstage” .
4. Uso: No utilice este equipo sin las
cubiertas o paneles.
5. Limpieza: Limpie el conector del
“headstage” con un paño húmedo a
fin de quitar los derrames de sales.
Evite derramar líquidos sobre el
“headstage”.
El conector de entrada fabricado de
Teflon debe mantenerse muy limpio.
Puede hacerse una limpieza
efectiva rociando con alcohol o con
un algodón humedecido con agua
desionizada. En la medida de lo
posible evite el uso del gas freón,
puesto que es dañino para el medio
ambiente.
Condiciones de seguridad ambiental
1. Para uso interior.
2. Fluctuaciones eléctricas en la fuente
de suministro: no deben exceder
±10% del voltaje nominal.
3. Temperatura: entre 5 °C y 40 °C.
4. Altitud: hasta 2.000 m
5. Este instrumento está diseñado
para ser usado en condiciones de
laboratorio. Debe operarse
únicamente en un ambiente limpio y
seco. No lo use en un ambiente
húmedo ni mojado.
Precauciones contra la estática
El “headstage” puede manejarse con
seguridad, bajo condiciones normales.
Sinembargo, si usted se encuentra en un
laboratorio donde la estática es alta (por
ejemplo, si escucha y percibe chispas
cuando toca los objetos), usted debería
tocar inmediatamente un objeto metálico
que esté en contacto con tierra, antes de
tocar el “headstage”.
No apague el interruptor principal del
Axopatch 200B cuando manipule la
entrada del “headstage” ya que esto
afectará el equilibrio térmico.
ADVERTENCIA
Envío del Axopatch 200B
El Axopatch 200B es un instrumento de
construcción sólida, diseñado para
soportar el transporte a cualquier parte
del mundo. Sinembargo, para evitar los
daños que pudieran ocurrir durante su
envío, el Axopatch 200B debe
empacarse adecuadamente.
En general, la mejor manera de empacar
el Axopatch 200B es en la caja original
de fábrica. Si ésta ya no se encuentra
disponible, le recomendamos que
envuelva cuidadosamente el Axopatch
200B en una funda o sábana de espuma
o de “empaque de burbujas” con un
espesor mínimo de 3 pulgadas (75 mm).
El Axopatch 200B, envuelto así, deberá
colocarse en una caja de cartón
resistente. Marque el exterior de la caja
con la palabra FRÁGIL y una flecha que
indique la posición hacia arriba.
No recomendamos el uso de bolitas de
espuma sueltas para proteger el
Axopatch 200B. Si la caja se cae
accidentalmente durante el transporte,
es muy probable que el Axopatch 200B
se desplace dentro del contenedor con
las bolitas de espuma sueltas y se dañe.
Si necesita enviar su Axopatch 200B a
otra localidad, o de regreso a la fábrica, y
no posee el empaque adecuado, Axon
Instruments puede enviarle el material
necesario por un cargo mínimo. Esto
podría parecerle un gasto superfluo que
preferiría evitar, pero es económico
comparado con lo que costaría la
reparación de un instrumento que ha
sufrido daños durante el envío.
Es su responsabilidad empacar el
instrumento adecuadamente antes de
enviarlo. Si no lo hace así y resulta
dañado, el transportista no será
responsable ni aceptará su reclamo de
indemnización.

Axopatch 200B, Copyright 1997-1999, Axon Instruments, Inc.
Explanation of symbols
Explication des symboles
Erklärung der verwendeten symbole
Explicación de símbolos
Symbol
Symbole
Symbol
Símbolo
Description
Description
Beschreibung
Descripción
Direct current
Courant continu
Gleichstrom
Corriente continua
~Alternating current
Courant alternatif
Wechselstrom
Corriente alterna
On (Supply)
Allumé (alimentation)
An (Netz)
Encendido (suministro)
oOff (Supply)
Éteint (alimentation)
Aus (Netz)
Apagado (suministro)
On (Supply)
Allumé (alimentation)
An (Netz)
Encendido (suministro)
Off (Supply)
Éteint (alimentation)
Aus (Netz)
Apagado (suministro)
Protective conductor terminal
Borne du conducteur de protection
Schutzleiterpol
Terminal de conductor protector

INFORMACION IMPORTANTE
Axopatch 200B, Copyright March 1997-1999, Axon Instruments, Inc.

i
Axopatch 200B, Copyright 1997-1999, Axon Instruments, Inc.
COPYRIGHT
THE CIRCUITS AND INFORMATION IN THIS MANUAL ARE
COPYRIGHTED AND MUST NOT BE REPRODUCED IN ANY FORM
WHATSOEVER WITHOUT WRITTEN PERMISSION FROM AXON
INSTRUMENTS, INC.
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.
DISCLAIMER
THIS EQUIPMENT IS NOT INTENDED TO BE USED AND SHOULD NOT BE
USED IN HUMAN EXPERIMENTATION OR APPLIED TO HUMANS IN ANY
WAY.

ii
Axopatch 200B, Copyright March 1997-1999, Axon Instruments, Inc.
LATE INFORMATION
Please check the back of this manual. If there are pages in yellow, these should be read
first. They contain errata and information that became available too late for inclusion in
the body of the manual.

TABLE OF CONTENTS •iii
Axopatch 200B, Copyright 1997-1999, Axon Instruments, Inc.
TABLE OF CONTENTS
Page
LIST OF FIGURES AND TABLES ................................................................................... vii
CHAPTER 1: INTRODUCTION..........................................................................................1
CHAPTER 2: FUNCTIONAL CHECKOUT........................................................................3
CHAPTER 3: USE OF THE PATCH CLAMP - A TUTORIAL........................................11
Single Channel Recording (Model Cell) ......................................................................12
Pipette Offset Adjustment ............................................................................................12
Using the TRACK Mode ......................................................................................12
Using the V-CLAMP Mode..................................................................................13
Adjustment of Pipette Capacitance Compensation ......................................................14
Adjustment of Leak Subtraction...................................................................................14
Whole-Cell Recording (Model Cell) ............................................................................15
Pipette Offset Adjustment ............................................................................................16
Whole-Cell Capacitance Compensation.......................................................................16
Series Resistance Compensation ..................................................................................19
Brief Method For Setting Series Resistance Compensation.................................19
Detailed Method For Setting Series Resistance Compensation ...........................22
Current Clamp (Model Cell).........................................................................................28
Single-Channel Recording (Real Cell) .........................................................................30
Whole-Cell Recording (Real Cell) ...............................................................................35
CHAPTER 4: INTERFACING A COMPUTER TO THE AXOPATCH 200B .................41

iv •TABLE OF CONTENTS
Axopatch 200B, Copyright 1997-1999, Axon Instruments, Inc.
CHAPTER 5: LOW NOISE RECORDING TECHNIQUES ............................................. 43
Glass Type And Coating...................................................................................... 44
Seal....................................................................................................................... 47
Signal Generator .................................................................................................. 48
CHAPTER 6: REFERENCE SECTION: INSTRUMENT OPERATION ......................... 49
Bridge Mode ................................................................................................................ 49
Capacitance Measurements.......................................................................................... 49
Command Potentials .................................................................................................... 50
Holding Command ............................................................................................... 50
Seal Test............................................................................................................... 51
Current Clamp.............................................................................................................. 51
Membrane Potential ............................................................................................. 51
Whole-Cell Current Clamp .................................................................................. 51
Whole-Cell Parameters ........................................................................................ 52
Electrode Capacitance Compensation.................................................................. 52
Limitations ........................................................................................................... 53
Electrochemistry .......................................................................................................... 54
Headstage..................................................................................................................... 54
Offset Adjustment For Headstage........................................................................ 54
Frequency Boosting ............................................................................................. 55
Case Ground Connector....................................................................................... 55
Mounting the Headstage ...................................................................................... 55
Cleaning ............................................................................................................... 55
Static Precautions................................................................................................. 56
Optical Pick-up .................................................................................................... 56
Acoustic Pick-up .................................................................................................. 56
Tuning the Headstage........................................................................................... 56
Holders.........................................................................................................................57
Features ................................................................................................................ 57
Parts...................................................................................................................... 58
Use ....................................................................................................................... 59
Glass Dimensions................................................................................................. 61

TABLE OF CONTENTS •v
Axopatch 200B, Copyright 1997-1999, Axon Instruments, Inc.
Adapters ................................................................................................................61
Input BNCs ...................................................................................................................61
Output Section ..............................................................................................................63
Filter......................................................................................................................63
Output Gain (
α
αα
α
) ....................................................................................................63
Output BNCs.........................................................................................................64
Panel Meter...................................................................................................................67
Power-Supply Voltage Selection and Fuse Changing ..................................................68
Supply Voltage......................................................................................................68
Changing the Fuse.................................................................................................68
Probe Temperature........................................................................................................68
Zap ................................................................................................................................69
CHAPTER 7: REFERENCE SECTION: GENERAL INFORMATION............................71
Grounding and Hum .....................................................................................................71
Model Cell ....................................................................................................................72
Model Bilayer ...............................................................................................................73
Power-Supply Glitches .................................................................................................74
Ten-Turn Potentiometers..............................................................................................74
CHAPTER 8: REFERENCE SECTION: PRINCIPLES OF OPERATION .......................75
Headstages ....................................................................................................................75
Principals of Operation .........................................................................................75
Resistor Feedback .........................................................................................75
Capacitor Feedback.......................................................................................76
If the Probe Output is Slow, How Can Voltage Clamping Be Fast? ............78
What is Clamped During Voltage Clamping? ..............................................79
Capacitance Compensation...........................................................................................79
Pipette Capacitance Compensation...............................................................79
Whole-Cell Capacitance Compensation .......................................................81
Absolute Value..............................................................................................83
Limitations ....................................................................................................83
Series Resistance ..........................................................................................................83

vi •TABLE OF CONTENTS
Axopatch 200B, Copyright 1997-1999, Axon Instruments, Inc.
Absolute Value............................................................................................. 83
Correction, Prediction, and Lag........................................................................... 83
Saturation Effects......................................................................................... 87
Oscillations................................................................................................... 90
Using Lag to Prevent Oscillations................................................................ 90
Limitations ................................................................................................... 90
Pipette Offset ............................................................................................................... 91
Leak Subtraction .......................................................................................................... 92
Zap ............................................................................................................................... 93
Lipid Bilayers .............................................................................................................. 93
Experimental Techniques..................................................................................... 93
Noise vs. Access Resistance ........................................................................ 95
Current and Voltage Conventions................................................................................ 96
Trouble Shooting ....................................................................................................... 101
Chapter 9: SPECIFICATIONS ......................................................................................... 103
Chapter 10: REFERENCES ............................................................................................. 119
Chapter 11: HEADSTAGE TUNING PROCEDURE...................................................... 121
INDEX ............................................................................................................................... 127
WARRANTY .................................................................................................................... 129
WARNING ........................................................................................................................ 131
CIRCUIT DIAGRAMS REQUEST .................................................................................. 133

FIGURES AND TABLES •vii
Axopatch 200B, Copyright 1997-1999, Axon Instruments, Inc.
LIST OF FIGURES AND TABLES
Page
Figure 1 Connections for testing Axopatch 200B and PATCH-1U model cell................. 6
Figure 2 Pipette capacity compensation ..........................................................................15
Figure 3 Whole-cell capacity compensation.................................................................... 19
Figure 4 Maximum % PREDICTION as a function of voltage step................................ 21
Figure 5 Series resistance compensation, brief method................................................... 22
Figure 6 Series resistance compensation, detailed method......................................... 26,27
Figure 7 Pipette resistance measurement using SEAL TEST.......................................... 32
Figure 8 Change in resistance while forming a seal ........................................................ 33
Figure 9 Going whole cell: Capacity transients observed when rupturing the patch ..... 37
Figure 10 Going whole cell: Capacity transients observed during
Amphotericin partitioning .................................................... 38
Figure 11 Exploded view of the holder..............................................................................59
Figure 12 Ag/AgCl pellet assembly...................................................................................60
Figure 13 PATCH-1U model cell ...................................................................................... 73
Figure 14 MCB-1U bilayer model ..................................................................................... 73
Figure 15 Resistive headstage............................................................................................ 75
Figure 16 Capacitive headstage ......................................................................................... 76
Figure 17 Signal handling during resets ............................................................................78
Figure 18 Pipette capacitance compensation circuit..........................................................80

viii •FIGURES AND TABLES
Axopatch 200B, Copyright 1997-1999, Axon Instruments, Inc.
Figure 19 Whole-cell capacitance compensation circuit ..............................................81
Figure 20 Using the injection capacitor to charge the membrane capacitance.............82
Figure 21 Integrator driving bilayer model ...................................................................94
Figure 22 Typical current noise in bilayers as a function of series resistance..............96
Figure 23 Total current noise as a function of bandwidth ...................................105,106
Figure 24 Frequency tuning of whole cell configuration............................................123
Figure 25 Reset transient compensation .....................................................................126
Table I Glass electrical and thermal properties.........................................................46

INTRODUCTION •1
Chapter 1
Chapter 1
INTRODUCTION
The Axopatch 200B is an improved and enhanced version of the Axopatch 200A amplifier
that ushered in a new generation of patch-clamp amplifiers. It offers unsurpassed
performance intight-seal patch clamp for single-channel and whole-cell voltage and current
clamping. Its noise in single-channel recording is the lowest of any available patch clamp;
its series-resistance compensation in whole-cell mode is the most effective of any existing
patch clamp, and it includes series resistance compensation in current clamp. Three
headstage settings offer an extremely wide range of recording capability, from single-
channel to loose patch to whole-cell. In addition, it includes built-in support for
capacitance and voltammetric measurements, and a novel slim headstage design that allows
easy pipette access to the experimental preparation.
The Axopatch 200B achieves its ultra-low noise performance by cooling components of the
innovative capacitive feedback circuitry used for single-channel recording. This
technology was developed by Axon Instruments engineers over a period of several years,
with extensive design and test contributions from scientific consultants.
The capacitive feedback technique is complicated. The headstage output has to be
periodically reset every time the voltage across the capacitor increases towards the limits of
the power supply of the instrument. Much of the circuitry of the Axopatch 200B is devoted
to eliminating the transients introduced by these resets. In most circumstances, the
transient elimination is so good that the resets will not affect the recording and the benefits
of the capacitor feedback will be available without penalty.
For whole-cell recording, the noise benefits of the capacitive feedback technique are
swamped by the noise sources of the electrode and the membrane capacitance. Since the
noise benefits cannot be realized, and at the same time the frequency of resets is high

2 •INTRODUCTION
Axopatch 200B, Copyright 1997-1999, Axon Instruments, Inc.
because of the larger average currents, the Axopatch 200B uses the traditional resistive-
feedback technique for whole-cell recording.
Patch clamping is a powerful technique that permits the direct observations of the behavior
of the small ionic currents that flow through a single ion channel protein. To extract the
most from the technique, meticulous attention to detail is required. We have designed the
Axopatch 200B with great care and we are confident that it is an excellent tool. But the
benefits of this instrument will not be realized if the user is not well versed in its operation
and at the same time knowledgeable about the experimental techniques. Therefore, we
have written this manual with two goals in mind. The first is to explain the operation of the
instrument and many of the principles that underlie its design. The second is to provide the
user with a guide to experimental techniques that our customers and scientific consultants
have found useful during many years of experience in patch clamping.
We hope that you will find this manual to be a useful laboratory companion. We aim to
revise it periodically and we look forward to receiving any suggestions that you might have
for its improvement.
NOTE
The CV 203BU Headstage will feel warm to the touch during normal use
(with headstage cooling ON). This is due to the operation of the Peltier
device that cools the critical headstage circuitry to achieve the extremely
low noise levels possible with the Axopatch 200B.

FUNCTIONAL CHECKOUT •3
Chapter 2
Chapter 2
FUNCTIONAL CHECKOUT
When you receive your Axopatch 200B, you should first run a functional checkout to
ensure the proper functioning of the instrument. All units are burned-in and thoroughly
tested at the factory before shipping. If you observe any damage caused by shipping or if
you encounter problems with the functional checkout, please call the factory.
Startup Procedure
For the initial checkout, the Axopatch 200B should be situated on a benchtop away from
other equipment. Do not install in a rack until the checkout is complete. Make sure that
the power is OFF. An oscilloscope is the only other piece of equipment required for these
tests. A large sheet of aluminum foil is needed.
1) The only connections to the Axopatch 200B should be: a) the power cable, b) the
headstage, c) a cable from the SCALED OUTPUT BNC to one channel of the
oscilloscope.
Take care to prevent static discharge near the headstage input connector.
Turn the power on.

4 •FUNCTIONAL CHECKOUT
Axopatch 200B, Copyright 1997-1999, Axon Instruments, Inc.
2) Set the front panel controls of the Axopatch 200B as follows:
PIPETTE OFFSET: About 5.0
ZAP 0.5 ms
PIPETTE CAPACITANCE COMP.: Minimum
(fully counterclockwise)
SERIES RESISTANCE COMP. % PREDICTION: 0 %, OFF
SERIES RESISTANCE COMP. % CORRECTION: 0 %, OFF
SERIES RESISTANCE COMP. LAG: 1 µs
WHOLE CELL CAP.: 0 pF, OFF
SERIES RESISTANCE: 0 MΩ
HOLDING COMMAND: 0 mV, x1, OFF
SEAL TEST: OFF
METER: Set switch to I
MODE: V-CLAMP
CONFIG.: WHOLE CELL (β= 1)
OUTPUT GAIN: α= 10
LOWPASS BESSEL FILTER: 5 kHz
LEAK SUBTRACTION: ∞MΩ, OFF
Test the noise:
3) Shield the headstage with a large sheet of aluminum foil. Wrap the foil loosely and
completely around the headstage. Leave room at the headstage input for the model cell
in the next test. Connect the foil shield to the ground input of the headstage (gold-
plated 1 mm socket at the rear of the probe) using a clip-lead. The easiest way to do
this is to connect the clip-lead directly to the foil and to the 1 mm pin inserted into the
headstage ground socket. (Ground is available from the gold-plated 1 mm socket at the
rear of the probe, from the yellow 4 mm socket on the rear-panel of the main unit, or
from the BNC shields.)