With the WaveNeuro Four Channel Headstage Kit, users can more conveniently connect up to four working electrodes to a single headstage. To make this possible, the Four Channel Headstage Kit includes an adapter board, to which a special interface cable and four-channel headstage cable connects. Terminating this assembly are the four-channel headstage-to-microelectrode coupler wires, which includes sockets for four working electrodes (Yellow, Red, Blue, and Green) and one reference electrode (White).
The Four Channel Headstage Kit finds application in several areas, yet to be fully realized by the FSCV research community:
- Easy throughput. Deliver the same waveform to four channels simultaneously, and measure current at each channel independently. In this case, you might install the electrodes into the same region of the brain, same tissue, or same flow cell and gain n=4 with a single experiment.
- Multiple analytes. Imagine measuring multiple analytes in your system simultaneously. Look at dopamine, serotonin, adenosine, and other molecules simultaneously - simply apply the appropriate waveform to each channel independently.
The FSCV community has yet to release seminal papers on the topic of multichannel FSCV. Pine Research hopes to promote the growth of FSCV into this area by providing a well-designed commercial solution for those needing multichannel FSCV.
Pine Research currently offers working driven headstage amplifiers. In a working driven system, the reference electrode is grounded. The FSCV potential waveform (ramp) is connected to the non-inverting input of the operational amplifier, while the working electrode is connected to the inverting input. In this arrangement, the voltage at the microelectrode will follow the ramp applied to the inverting input. 
Even when no electrodes are connected (connector just in air) to the headstage amplifier cable, which is connected to the WaveNeuro, HDCV will show a current response that follows the applied waveform. As described below, this is expected.
In this two-electrode configuration, current arising from electron-transfer reactions, such as the oxidation of dopamine, passes between reference and working electrodes. The measured current passes through the headstage amplifer, where it is converted to voltage, and sums with the the ramp voltage at the inverting input. Mathematically,
where is the output voltage, is input current, is feedback resistor (gain), and is the CV ramp voltage. By rearrangement, the signal voltage (proportional to the current across the feedback resistor in the headstage) is then
HDCV software, which supports the WaveNeuro FSCV Potentiostat system, performs software subtraction of the ramp according to this relationship, resulting in only the true differential current measurement.1
1. Takmakov, P.; McKinney, C. J.; Carelli, R. M.; Wightman, R. M. Instrumentation for Fast-Scan Cyclic Voltammetry Combined with Electrophysiology for Behavioral Experiments in Freely Moving Animals. Rev. Sci. Instrum. 2011, 82, 74302.
R.M. Wightman et. al. have reported on this topic in depth If, after reviewing this document, you have any questions about our neuroelectrochemical research products, please do not hesitate to contact us.