Bipotentiostat – Cypress Systems EI-400

We designed the Cypress Systems EI-400 bipotentiostat to take advantage of the unique properties of ultramicro carbon fiber electrodes for in-vivo and in-vitro detection and quantitation of neurotransmitters such as dopamine and norepinephrine. Its high sensitivity, stability, and dual-outputs are also attractive for controlling and monitoring in Scanning Electrochemical Microscopy (SECM). Both channels can be driven by an external signal source and input/output triggers are available to control remotely CV or other experiments. Variable slope triangle waves are formed digitally with two millivolt steps that have been shown to work well for fast scan in-vivo applications. Bipolar offset voltages are provided for both channels with choice of internal or external triggering to start scans.

Remote pre-amplifiers (head stages) are used to convert the low-level currents to voltages suitable for amplification. This arrangement results in low noise and fast response, especially when used with a Faraday case to shield and minimize external noise. The gain factor for the head stages may be specified to fit the requirements of the experiment. A total gain range of one million is possible – going from high to low sensitivity. A low-pass cutoff filter is included in each of the current-to-voltage amplifiers. Implemented with a continuously variable cut-off frequency, these two pole filters permit optimal enhancement of the signal-to-noise ratio.

A digit panel meter displays your parameters settings, including: waveform, bias-potential offset, filter cut-off frequency, and allows you to monitor gain and signal outputs. At low scan rates, data can be recorded with a X-Y chart recorder, while fast scan rates with a digital storage oscilloscope. Captured data can then be transferred to a computer for analysis.

Techniques:

• Fast scan voltammetry with microelectrodes
• High sensitivity measurement to 10 pA
• Dual electrode voltammetry
• In-vivo study of neurotransmitters
• Scanning electrochemical microscopy (SECM)

Features:

• Scan rates to 1,000 V/s
• Continuously programmable bandpass filter
• Internal or external trigger to start experiments
• Adjustable bias potential for both working electrodes
• Connector for external input voltage
• Remote pre-amplifiers