Page 1 Modular Potentiostats Potentiostat, Dual Picostat & QuadSta t Overload Potentiostat Dual PicoStat Channel 1 Channel 2 Power Status Trigger Overload Overload Channel 1 Channel 2 Channel 3 Channel 4 QuadStat ® e-corder eDAQ www. .com...
Page 2 All other trademarks are the properties of their the time of printing. Changes may have been made respective owners. to the software and hardware it describes since then: eDAQ Pty Ltd reserves the right to alter Products: Potentiostat (EA161) specifications as required. Late-breaking information Potentiostat (EA163) may be supplied separately.
Page 3: Table Of Contents
The Status Indicator The Overload Indicator How to Use this Manual 2 The Back Panel 25 eDAQ Modular Potentiostats 2 Power Connector, On/Off 25 Checking the unit 2 E Out, I Out and E In Connectors 25 USB socket 26...
Page 4 Controlled Potential Electrolysis 70 Controlled Current Electrolysis 71 Amperometric Sensors 72 Biosensors 73 Microdialysis Sensor 73 Dissolved Oxygen (dO ) Sensors 74 Nitric Oxide (NO) Sensors 75 A Technical Aspects Potentiostat 77 Dual Picostat 79 QuadStat 81 B Troubleshooting eDAQ Potentiostats...
Page 5: Overview
EA164 us to send you the appropriate manual. potentiostat with gain ranges of 200 pA to 10 mA. They are designed for use with an e-corder ® system. Some of the uses of the Potentiostat, Picostat, and QuadStat, are mentioned in...
Page 6: How To Use This Manual
Contact your eDAQ distributor if you encounter a problem. You should also become familiar with the basic features of your e-corder system, which are discussed in the e-corder Manual which will be placed as a pdf file on your computer hard disk when you install the software.
Page 7: The Potentiostat
IMPORTANT: Always make sure that the e-corder is turned off before you connect or disconnect the Potentiostat. Failure to do this may result in damage to the e-corder and/or the Potentiostat.
Page 8: The Front Panel
Overload indicator light Potentiostat Online indicator light Alignment dot Figure 2–2 The Potentiostat electrode Working Electrode Auxiliary Electrode connector as seen when looking at the front panel. Working Electrode Shield Not connected Reference Electrode Shield Reference Electrode eDAQ Potentiostats...
Page 9: Electrode Cable
Color Electrode Table 2–1 Yellow Reference Color–coding on the leads of the electrode Green Working cable. Auxiliary coaxial shields which are maintained at the respective electrode potential. Electrode Cable The Potentiostat is supplied with an electrode cable comprising three To ensure good grip, the leads, with each lead terminated by an alligator clip.
Page 10: The Online Indicator
Normally cells are designed to keep the reference and working electrodes very close together, however, when a potential overload occurs, you also need to consider the distance between the auxiliary and working electrodes. eDAQ Potentiostats...
Page 11: The Back Panel
BNC output BNC input connectors connector Figure 2–3 The Potentiostat back panel. 4 mm socket, ground connector DB-9 pin, I C connectors C control signals Power lines C control signals Figure 2–4 The pin assignments for the I C DB-9 connectors. Input Output Note that a potential overload is quite different from a current overload...
Page 12: E Out, I Out And E In Connectors
E Out, I Out and E In Connectors The Potentiostat back panel has three BNC connectors labelled E Out, I Out, and E In. The E In is connected to the Output of the e-corder, usually Output + is used.Reverse the polarity of the Potentiostat by using e-corder Output –.
Page 13: Connecting The Potentiostat
Faraday cage be electrically grounded to act as an effective shield against electrical interference. The Potentiostat itself is grounded via its connection to the e-corder unit which is in turn earthed via the three pin mains power connector. It is of course important that the power socket that you are using is well earthed.
Page 14 The Potentiostat shown connected to an e-corder, back view. First make sure that the e-corder is turned off. Then connect the I C connector on the back panel of the e-corder, and the cable to the I other the other end to the I C Input connector on the back panel of the Potentiostat.
Page 15: First Use
The reminder of this chapter assumes that you have connected the current signal to e-corder Input Channel 1 and the potential signal to e-corder Input Channel 2. (It is possible when using Chart or Scope software to connect the Potentiostat to other e-corder input channels, in which case the description that follows would change accordingly).
Page 16 1 V should produce a current of 10 μA, while other potential settings should produce corresponding currents. Select Potentiostat in the Channel pop-up menu Figure 2–7 Potentiostat controls with Chart software. Signal display area Drag ticks and labels to adjust axis eDAQ Potentiostats...
Page 17: Potentiostat Control Window
Potentiostat Control Window With Chart software, the Potentiostat Control window, Figure 2–7, is accessed from the Potentiostat command in the Channel Function pop- up menu. It control the various current ranges and filtering options for the Potentiostat. With Scope software, the corresponding controls are shown in Figure 2–8.
Page 18 You can stop/start the signal scrolling by clicking the Pause/Resume button You can shift or stretch the vertical Amplitude axis to make the best use of the available display area — similar to the amplitude axis in the main Chart, Scope or EChem window. eDAQ Potentiostats...
Page 19 The Potentiostat incorporates four low-pass filters at 10 kHz, 1 kHz, 100 Hz and 10 Hz for removal of high frequency signals (‘noise’). In addition the e-corder provides filter settings at 1, 2, 5, 20, 50, 200, 500, and 2000 Hz.
Page 20 If the High Stability box is ticked then extra capacitance is introduced into the Potentiostat control loop. This stabilizes the Potentiostat in situations where oscillation is encountered (for example where large surface area electrodes are being used in highly resistive solutions). eDAQ Potentiostats...
Page 21 Calibrate button! For best results allow about 10 minutes after opening powering up the e-corder before using the Calibrate function. This allows the unit to warm up — ambient temperature variation of more than a few degrees during an experiment may require periodic recalibration to maintain maximum accuracy.
Page 22 Output at E In. Thus it should be considered a ‘relative zero’. Recalibatrion is required after you: • select a different range for the Potentiostat applied potential, page • turn iR Compensation on or off, page •...
Page 23 compensation will vary during the sweep, and it is possible that the potentiostat will go into oscillation at some point. To avoid this happening it is usual to always slightly undercompensate, that is, to find the point of ideal compensation and then to reduce the setting slightly. The amount of ‘undercompensation’...
Page 24: Maintenance
(reference electrodes, in particular, tend to become clogged or dry out with age), and the design and condition of the reaction vessel, and any salt bridges that you are using. eDAQ Potentiostats...
Page 25: The Dual Picostat
• high impedance voltmeter (Chart or Scope software). The mode of operation is under software control. IMPORTANT: Always make sure that the e-corder is turned off before you connect or disconnect the Dual Picostat. Failure to do this may result in damage to the e-corder and/or the Dual Picostat.
Page 26: The Front Panel
Power Status Trigger Overload Overload Overload indicators Alignment dot Working Electrode Auxiliary Electrode Figure 3–2 A Dual Picostat electrode connector as seen when looking at the front Working Electrode Shield Not connected panel. Reference Electrode Shield Reference Electrode eDAQ Potentiostats...
Page 27: Electrode Cable
Color Electrode Table 3–1 Yellow Reference Color-coding on the leads of the electrode Green Working cables. Auxiliary Electrode Cable The Dual Picostat is supplied with two three-lead electrode cables, with each lead terminated by an alligator clip. The Reference and Working electrode leads are shielded to protect the signals from external interference.
Page 28: The Status Indicator
NOTE: A potential overload is quite different from a current overload condition. A current overload is caused when the current signal exceeds the full scale limits of the sensitivity setting of the current channel. This is due to a low resistance between the auxiliary and eDAQ Potentiostats...
Page 29: The Back Panel
2, I out 1 and 2, and E in and Ext Trigger. The E in is connected to the Output of the e-corder, usually Output + is used. The Dual Picostat provides up to four analog signals: the potential signals (E out 1 and 2);...
Page 30: Usb Socket
Input and Output. The Input connector carries the various control signals (for gain range and filter selection) to and from the e-corder. A cable is provided with the Dual Picostat for this purpose. The pin assignments are shown in Figure 3–4.
Page 31: Connecting The Dual Picostat
The case of the Dual Picostat is grounded via its connection to the e-corder unit which is in turn earthed via the three pin mains power connector. It is of course important that the power socket that you are using is well earthed.
Page 32 (Iout 1 and Iout 2) and one potential signal (Eout 1). Connect the Picostat as shown in Table 3–3. Note that it is also possible when using Chart software to connect the Dual Picostat to other e-corder input channels but in these cases the discussion that follows would change accordingly. eDAQ Potentiostats...
Page 33 Figure 3–5 The Dual Picostat shown connected to an e-corder, front view. Omit this cable for single channel or 4-electrode operation Figure 3–6 The Dual Picostat shown Single channel or connected to an e-corder, 4-electrode operation back view. Dual channel or...
Page 34: First Use
The settings for these channels are controlled using the standard Input Amplifier dialog box, described in the Chart Software Manual which is installed as pdf files in the eDAQ Documentation folder on your computer hard disk.
Page 35 Figure 3–7 Accessing the Dual Select Dual Picostat Picostat controls with from the Channel 1 Chart software. pop-up menu Current signal display area Drag ticks and labels to adjust axis scaling Use the Change button to go to This number refers to the Chart software the Dual Picostat CH2 controls to channel to which the Iout signal is connected select the operating mode...
Page 36 Ohm’s law: I = E/R so that with a 10 Mohm test resistor, R, in place, an applied potential, E, of 1 V should produce a current, I, of 100 nA, while other potential settings should produce corresponding currents. eDAQ Potentiostats...
Page 37 Cell Control The Dual Picostat can be in one of three cell modes, controlled by the Cell radio buttons: • Standby: If Standby cell mode is selected the auxiliary and reference electrodes are isolated by an internal relay which effectively means that all the electrodes are at a ‘floating’ potential and that no current will be passed through your experimental solution.
Page 38 Ussing chambers. Note that there is only one current signal (at Iout 1), and one potential signal (at Eout 1). Also note that the working and auxiliary lead wires of CH2 are left unconnected. eDAQ Potentiostats...
Page 39 The Dual Picostat has ranges of 2 pA to 10 μA (if you require a system to monitor larger currents, use the eDAQ Potentiostat which has ranges up to 100 mA). Set the range so that it is larger than the biggest current that you expect to encounter during your experiment.
Page 40 In addition, with Chart and Scope software, there is a Mains Filter checkbox. If this is ticked, then the e-corder will apply a filtering algorithm to the incoming signal which removes repetitive signals occurring at 50 or 60 Hz which are typical of mains interference. Note that the Mains Filter is not a notch filter, and so it can remove 50 or 60 Hz interference even if it is not a pure sinusoidal function.
Page 41: Maintenance
The Dual Picostat will not require maintenance during daily operation. However, you should periodically check it for optimum results. First set up the Dual Picostat and e-corder as outlined earlier in this Chapter. Connect the electrode cables connected, and attached to the...
Page 42 E, of 1 V should produce a current, I, of 100 nA, while other potential settings should produce corresponding currents. If the current signal does not obey Ohm’s law, then first recheck your connections of the Dual Picostat to the e-corder, page 27. Then check with the second electrode cable.
Page 43: The Quadstat
164-113 and later). Earlier QuadStat units did not have a ZRA operating mode, did not have all the gain range settings of the present version, and had a 1 Mohm dummy cell (instead of the present 100 kohm dummy cell). eDAQ Potentiostats...
Page 44: The Front Panel
(Table 4–1). The RE and WE leads are shielded to protect the signals from external interference. The shields are driven to the same potential as the electrode to minimize lead capacitance. eDAQ Potentiostats...
Page 45: The Online Indicators
Color Electrode Table 4–1 Yellow Reference Color-coding on the leads of the electrode Green Working cables. Auxiliary If two-electrode operation is required the auxiliary and reference electrode leads (red and yellow) can be attached to the single ‘counter electrode’. The Online Indicators Along the lower edge of the QuadStat front panel are a series Online indicators, Figure...
Page 46 Figure 4–2 The QuadStat back panel. 20-pin socket for screw DB-9 pin, I C connectors terminal adaptor, Figure 4–3. Input and output signals Figure 4–3 The 20-pin screw terminal adaptor. 20-pin terminal adaptor. Push firmly into socket eDAQ Potentiostats...
Page 47: The Back Panel
Input and Output. The Input connector provides power to the QuadStat and carries the various control signals (for gain range and filter selection) to and from the e-corder connection. A cable is provided with the QuadStat for this purpose. The pin assignments are...
Page 48: Grounding Connector
Faraday cage be electrically grounded to act as an effective shield against electrical interference. The QuadStat itself is grounded via its connection to the e-corder unit which is in turn earthed via the three pin mains power connector. It is also important that the power socket that you are using is well earthed.
Page 49 E In is only required for potentials of more than ±2.5 V, or for pulsed or ramped Single channel operation waveforms. To e-corder Output or To e-corder Inputs” waveform generator To e-corder Input: To e-corder Output or Multiple channel operation with the same waveform generator applied waveform on each channel.
Page 50: Connecting The Quadstat
±2.5 V, or is to be pulsed or ramped during the experiment, then the E In input must be connected to a suitable external signal, such as from the Output of the e-corder, or a waveform generator, Figure 4–6.
Page 51 Such an arrangement is shown in Figure 4–7. If you need to reverse the polarity of the QuadStat, use e-corder Output –. With these connections, when you use the software to set a more positive voltage, a more reducing potential will be applied at the working electrode.
Page 52 QuadStat to other e-corder input channels in which case the description that follows would change accordingly). When using EChem software, e-corder Input 1 is always set to be the current signal (the I channel), and e-corder Input 2 is automatically set to be the potential signal (the E channel).
Page 53: Using A Common Reference And Auxiliary
Input Amplifier dialog box, described in the Chart and Scope Software Manuals. Using a Common Reference and Auxiliary Often the QuadStat will be used with a single reference electrode, RE, and a single auxiliary electrode, AE , (on QuadStat channel 1) with multiple working electrodes (WE , WE , WE...
Page 54: Using Multiple References And Auxiliaries
After you have installed the software, connected the e-corder and computer, and connected the QuadStat as described above, you are ready to begin. When the e-corder is turned on, and Chart software started, the QuadStat Online indicators (green), Figure 4–1 on page 40, should light for every channel connected.
Page 55: Quadstat Control Window
From the Chart software Channel 1 pop-up menu, select the ‘QuadStat’ command, (also on Chart software Channels 3, 5, 7 if all four working electrodes are being used) which accesses the QuadStat control window, Figure 4–9, or Figure 4–10. The QuadStat control window allows you to preview the current signal without actually recording the signal to the computer hard disk.
Page 56 Click the QuadStat button software. Current signal display area Figure 4–10 Accessing the QuadStat controls with Scope software. Select QuadStat from the Channel Current signal Function pop-up display area menu Drag ticks and labels to adjust axis scaling eDAQ Potentiostats...
Page 57 With Scope software, the corresponding controls are shown in Figure 4–10. Signal Display The current signal is previewed scrolling across the display area. Note that the signal is not being recorded to hard disk at this stage, and that when the window is closed the signal trace is lost. You can stop/start the signal scrolling by clicking the Pause/Resume button You can shift or stretch the vertical Amplitude axis to make the best use...
Page 58 When you use the Chart and Scope software there is a Mains Filter checkbox. When ticked then the e-corder will apply a mains filtering algorithm to the incoming signal which removes repetitive signals occurring at 50 or 60 Hz which are typical of mains interference. Note that the mains filter is NOT a simple notch filter, and it can remove 50 or 60 Hz interference even if it is not a pure sinusoidal waveform.
Page 59 you close the control dialog (using EChem software) the QuadStat will revert to Standby mode until the Start button is clicked to begin a scan. If you are using Chart or Scope software, the QuadStat will remain in Real mode when the dialog is closed — this allows you to start and stop recording data while the electrodes remain active, which allows periodic recording of the signal from amperometric biosensors or in vivo electrodes without disturbing the environment...
Page 60: Quadstat Potential Window
Chart Setup menu. Working electrode potentials can then be adjusted independently on each connected QuadStat channel. This is equivalent to adjusting the potentials using the Applied Potential controls, Figure 4–11 The QuadStat Applied Potential controls with Chart software. eDAQ Potentiostats...
Page 61: Maintenance
First Use, page 50. If the current signal does not obey Ohm’s law, then first recheck your connections of the QuadStat to the e-corder, page 46. If the problem persists then it is possible that the electrode leads or the QuadStat itself has become damaged.
Page 62 Potentiostats...
Page 63: Techniques
C H A P T E R F I V E Techniques The Chart and Scope software supplied with your e-corder can be used to perform many different electrochemical techniques. This chapter provides an overview of these techniques, but you will need to also...
Page 64: Introduction
NOTE This potential difference is determined by a ‘command voltage’ which is The QuadStat also has sent from the e-corder output to the ‘E In’ connector of the, Dual internal potential Picostat, Figure 3–3, on page 25, Potentiostat, Figure 2–4, on page 7...
Page 65: Linear Scan Techniques
EChem software can perform Fast Cyclic Voltammetry (FCV) up to about 400 V/s but by this point you are reaching the limits of the bandwidth of the e-corder itself and your results may show some distortion. Also note that at very high gains the bandwidth of the potentiostat you are using is lessened and can also distort the voltammogram at fast sweep rates.
Page 66: Chronoamperometry With Chart
Chart software can be used to set a constant voltage of up to ±10 V (which is known as the command voltage) from the e-corder Output. This is sent to the Picostat or Potentiostat, or QuadStat, via the ‘E In’...
Page 67 Figure 5–1 Chart Setup menu Use the Stimulator command to access the Stimulator (applied potential waveform) controls, Figure 5–2 & Figure 5–3 Select stimulator mode Figure 5–2 Chart Stimulator (waveform output) controls Select output range Enter exact values as text. Use zero amplitude for constant output Baseline control can...
Page 68: Chronoamperometry With Scope
Figure 5–4, after a period of 10þs at the base potential of +0.5 V, two 30 s pulses of –0.70 V are to be applied each followed by a 30 s return to the base potential. eDAQ Potentiostats...
Page 69: Chronocoulometry
The experiment is usually first done on a blank solution containing only electrolyte, followed by a sample solution containing the substrate. The data is collected on separate pages in Scope and the ‘blank’ data subtracted with the Set Background command. You can then copy and paste the scan to a spreadsheet so that the differences can be plotted against 1/Ðt in a Cottrell graph.
Page 70 To configure Channel 3 you need to choose the Computed Input command from the Channel Function pop-up menu, which opens the Computed Input dialog box Figure 5–5. For more information refer to the Computed Input section in the Chart Software Manual. eDAQ Potentiostats...
Page 71: Chronopotentiometry
Galvanostat mode with Chart or Scope software. For correct operation make sure that the ‘CH 1 (I)’ cable of the Potentiostat is connected to Input 1 of the e-corder, and the ‘CH2 (E)’ cable of the Potentiostat is connected to Input 2.
Page 72 (or pH meter) than a galvanostat, or use the Potentiostat in High Z mode, page eDAQ Potentiostats...
Page 73: Chart Software
Chart software To switch to the Galvanostat mode of operation, choose the Potentiostat command in the Channel Function pop-up menu to open the control window, and turn on the Galvanostat and Dummy radio buttons, Figure 5–7. When in Galvanostat mode, the current and potential signals will be reversed from normal (potentiostatic) operation.
Page 74: Controlled Potential Electrolysis
(or, if reducing the substrate, to prevent the products of oxidation forming around the auxiliary electrode from reacting with the reduction products at the working electrode). The working electrode is usually constructed to have relatively large surface area so that a eDAQ Potentiostats...
Page 75: Controlled Current Electrolysis
greater amount of material can be electrolyzed in a small time — thus a plate or gauze electrode is usually chosen, although reticulated vitreous carbon (RVC) which has an open pore foam structure, is also a popular choice. The conversion of large amounts of substrate (> 100 mg) in reasonable times requires relatively high currents to be passed through the cell.
Page 76: Amperometric Sensors
— see the Chart Software Manual for more information. If multiple point, or non-–linear, calibration is required then the Chart Multiple Point Calibration extension can be used with up to twelve calibration points. eDAQ Potentiostats...
Page 77: Biosensors
If your biosensor only develops small currents (typically less than a microampere) it may be suitable for use with a two electrode system (working and counter electrode). In this case a low cost eDAQ Biosenor isoPod (EA352 or EPU352) might be a suitable alternative to a three electrode potentiostat.
Page 78: Dissolved Oxygen (Do ) Sensors
1 – 10 Hz filter setting on the Potentiostat, QuadStat, Picostat or isoPod, in order to minimise any electrical noise. The Mains Filter, where available, setting can also be employed to further reduce mains hum. Sampling rates of about 1 /s are usually optimal. eDAQ Potentiostats...
Page 79: Nitric Oxide (No) Sensors
Chart software Multiple Point Calibration extension to compensate for a non–linear electrode response. You can download the extension from www.edaq.com. Nitric Oxide (NO) Sensors Most polarographic nitric oxide sensors can be used with the Picostat,...
Page 80 Use the Chart software Multiple Point Calibration extension which can be downloaded from the eDAQ web site at www.edaq.com. The QuadStat and isoPod have the ability to zero (or offset) a background current signal which can be of use when trying to amplify...
Page 81: A Technical Aspects
The Potentiostat, Dual Picostat, QuadStat and other eDAQ Amps have been designed to be used with an e-corder system. All internal functions (gain ranges, filters, real/standby/dummy cell selection) of the Potentiostat, Picostat or QuadStat are controlled from the e-corder by sending information on a special communications connection called the ‘I...
Page 82 10 mA/V, provided by an I to V convertor and PGA. The maximum current output signal (I Out) is 10 V at any gain setting. Secondary amplification of the current signal is done by the e-corder. The gain and secondary amplification are set by the single ‘range’ menu in the software which offers a combined total of 21 current range settings from ±20 nA to ±100 mA in 1:2:5 steps,...
Page 83: Dual Picostat
An error voltage is generated from the difference between the voltage on the Reference electrode and the excitation (command) voltage set by the e-corder unit. This difference or error voltage drives a high gain power amplifier (VCVS – voltage controlled voltage source) the output of which is applied to the Auxiliary electrode in such a way as to minimise the error voltage.
Page 84 (zero volts) by a voltage-to-current convertor, the output of which reads directly in current units and is also applied to the e-corder unit. The Dual Picostat has three gain ranges of 100 pA/V, 1 nA/V, and 10 nA/V. The maximum current output signal (I Out) is 10 V at any gain setting.
Page 85: Quadstat
Back Panel Front Panel Subtractor Overload Detector Figure A–3 Error Voltage Overload Block diagram of the E Out – Σ QuadStat, Channel 1. (Working – voltage) Auxiliary Gain Power Amp E In Ref Amp (Command Σ Shield voltage) Hi Z Reference I Out Low–pass...
Page 86 PGA. The maximum current output signal (I Out) is 10 V at any gain setting. Secondary amplification of the current signal is done by the e-corder. The gain and secondary amplification are set by the single ‘range’ menu in the software which offers a combined total of twenty one current range settings from ±200 pA to ±10 mA in 2:5:10...
Page 87 The QuadStat is powered is powered by regulated +17 V, –17 V and +8 V DC lines from the e-corder, see Figure 4–4 on page 44. The use of DC power allows its use inside Faraday cages. Multiple–electrode potentiostat designs, for sensor work, have been reported in “Development of a computer controlled multichannel...
Page 88 Potentiostats...
Page 89: B Troubleshooting
Manual and Software Manuals, placed on your computer hard disc by the eDAQ Software Installer CD. In many cases, a problem can be fixed by turning the e-corder and computer off, checking connections, and starting again. Also try performing the maintenance checks on...
Page 90 • Try using the Potentiostat, Dual Picostat, or QuadStat with another e-corder (if available). If the Online indicator fails to light on the second e-corder, the Potentiostat, Picostat, or QuadStat, may be faulty — contact eDAQ. If it works correctly on a second e-corder then the first e-corder may be faulty —...
Page 91 The results show peaks or steps at the inverse polarity I expect to see (i.e. a peak may be occurring at 0.5 V when it should be at –0.5 V). • Check that you are connected to the correct Output (+ or –) of the e-corder. See Connecting the Potentiostat, page 9, or...
Page 92 Ensure common grounding by attaching the e-corder and computer to the same power board which is then attached to a three pin (grounded) power socket.
Page 93 the clips are still in good electrical contact with the correct pins in the input connector of the electrode cable, see Figure 2–2 on page Figure 3–3 on page 25, and Figure 4–2 on page 42. Also check that the shield pins have not shorted to any of the alligator clips.
Page 94 Potentiostats...
Page 95: C Specifications
Slew rate: 3 V/μs Electrometer Input resistance: Input bias current: < 1 pA @ 25°C Input voltage: ±10 V maximum Output voltage: ±10 V maximum Output offset voltage: ±0.8 V maximum Output offset drift: ±0.8 μV/°C Gain accuracy: 0.1% eDAQ Potentiostats...
Page 96 10 V Low pass filters: 10 000, 1000, 100, 10 Hz 3rd order Bessel e-corder filter settings: 10 kHz to 1 Hz in 10:5:2 steps Gain accuracy: 0.2% at ranges 1 mA or smaller 1% at ranges 10 mA or larger Drift with temperature: ±0.3 mV/°C...
Page 97 50 × 76 × 260 mm 1.96 × 3.0 × 10.2 inches Weight: 0.8 kg (1.8 lb) Operating conditions: 0 – 35°C 0 – 90% humidity (non-condensing) eDAQ reserves the right to alter these specifications at any time. Appendix C — Specifications...
Page 98: Dual Picostat
< ±1% FS on ranges of 10 pA – 1 nA < ±0.5% FS on ranges of 2 nA – 10 μ Filter setting: 10 Hz low-pass. 3rd order Bessel e-corder filter settings: 2 kHz to 1 Hz in 10:5:2 steps Drift with temperature: < 20 μV/°C Control Port C input and output: Male and female DB-9 pin connectors.
Page 99 50 × 76 × 260 mm 1.96 × 3.0 × 10.2 inches Weight: 0.8 kg (1.8 lb) Operating conditions: 0 – 35°C 0 – 90% humidity (non-condensing) eDAQ reserves the right to alter these specifications at any time. Appendix C — Specifications...
Page 100: Quadstat
< ±0.5% FS on ranges 200 nA – 10 mA < ±1% FS on ranges 200 pA – 100 nA Low pass filter: 10 Hz, 3rd order Bessel e-corder filter settings: 10 kHz to 1 Hz in 10:5:2 steps Drift with temperature: < 10 μV/°C Electrometer &...
Page 101 60 × 150 × 200 mm 2.4 × 5.9 × 7.9 inches Weight: 1.5 kg (3.3 lb) Operating conditions: 0 – 35°C 0 – 90% humidity (non-condensing) eDAQ reserves the right to alter these specifications at any time. Appendix C — Specifications...
Page 102 Potentiostats...
Page 103: D Electrochemical Equations
= potential at current peak for cathodic scan (V) = half potential as determined by cyclic voltammetry (V) 1 2 ⁄ n = the number of electrons transferred to (or from) the substrate molecule A = area of the exposed surface of the electrode (cm eDAQ Potentiostats...
Page 104 Nonetheless there may still be an appreciable uncompensated resistance which will cause to become larger – than predicted, the peaks to be broader, and the peak currents to be smaller. eDAQ Potentiostats...
Page 105: Chronoamperometry
Chronoamperometry The Cottrell Equation When chronoamperometry is performed on an unstirred solution at a planar electrode the faradaic current response is described by the Cottrell equation 2 ⁄ nFAD ----------------------------------- - 2 ⁄ 2 ⁄ 1000π where n = the number of electrons transferred to (or from) the substrate molecule F = Faraday's constant, 96485 C/mol A = area of the exposed surface of the electrode (cm...
Page 106: Chronocoulometry
Thus a plot of Q versus t should produce a straight line with an intercept of k, which in turn can be defined as: Γ k = nFA where Γ = surface concentration of adsorbed substrate (mol/cm = double layer charging. eDAQ Potentiostats...
Page 107 QuadStat 43 EChem software 1 eDAQ Amps Potentiostat 2 calibration QuadStat 2 multiple point 72 eDAQ modular potentiostats 2 non–linear 72 eDAQ potentiostats 1 potentiostat current signal 17 electrochemical equations 99 two point linear 72 electrode cable ZRA current signal 17...
Page 108 Dual Picostat 26 multiple step chronoamperometry 63 Potentiostat 8 QuadStat 44 neurotransmitter monitoring 34 nitric oxide sensor 75 high impedance voltmeter noise 8 Dual Picostat 33 normal pulse voltammetry 59 Potentiostat 5 High Stability Potentiostat 16 High Z mode Offset eDAQ Potentiostats...
Page 109 Dual Picostat 36 QuadStat 55 sensors Ohm’s law 20 amperometric 72 Online indicator biosensors 73 Potentiostat 6 dissolved oxygen 74 QuadStat 41 microdialysis 73 open circuit potential 6 nitric oxide 75 Overload indicator signal offset Dual Picostat 24 Dual Picostat 36 Potentiostat 6 QuadStat 55 QuadStat 41...
Page 110 36 zero resistance ammeter Dual Picostat 33 Potentiostat 14 ZRA mode Potentiostat 14 Potentiostat, electrode connection 5 eDAQ Potentiostats...
Page 111: License & Warranty
Responsibilities • been subjected to unusual physical, electrical, or environmental stress. This includes damage You and any others using any eDAQ product agree due to faulty power sockets, inadequate to use it in a sensible manner for purposes for which earthing, or power spikes or surges;...
Page 112 Jurisdiction eDAQ Pty Ltd is bound by the laws of New South Wales in Australia, and any proceedings shall be heard by the Supreme Court of New South Wales in Australia.

eDAQ e-corder Manual

1 Overview

2 The Potentiostat

3 The Dual Picostat

4 The Quadstat

5 Techniques

A Technical Aspects

B Troubleshooting

C Specifications

D Electrochemical Equations

License & Warranty

Quick Links

Need help?

Questions and answers

Related Manuals for eDAQ e-corder

Summary of Contents for eDAQ e-corder

Table of Contents