A potentiostat featuring an integrator transimpedance amplifier for the measurement of very low currents—Proof-of-principle application in microfluidic separations and voltammetry

Abstract

This work reports the design and construction of a novel potentiostat which features an integrator transimpedance amplifier as a current-monitoring unit. The integration approach addresses the limitations of the feedback resistor approach used for current monitoring in conventional potentiostat designs. In the present design, measurement of the current is performed by a precision switched integrator transimpedance amplifier operated in the dual sampling mode which enables sub-pA resolution. The potentiostat is suitable for measuring very low currents (typical dynamic range: 5 pA-4.7 μA) with a 16 bit resolution, and it can support 2-, 3- and 4-electrode cell configurations. Its operation was assessed by using it as a detection module in a home-made capillary electrophoresis system for the separation and amperometric detection of paracetamol and p-aminophenol at a 3-electrode microfluidic chip. The potential and limitations of the proposed potentiostat to implement fast potential-scan voltammetric techniques were demonstrated for the case of cyclic voltammetry.

Electrochemical Detection and Characterization of Nanoparticles with Printed Devices

“…Electrochemical techniques can address some of these issues since low-cost, user-friendly, portable potentiostats can be easily fabricated [11,12,13] and even self-powered devices are available [14]. Electrochemistry also provides good analytical sensitivity, which has proven convenient for environmental [15] or clinical analysis [16] and in combination with disposable single-drop electrodes become an excellent system for simple, cost-effective, and in situ analysis in decentralized settings.…”

Miniaturization of Cyclic Voltammetry Electronic Systems for Remote Biosensing

“…In the development of electrochemical measurement systems and distribution to the final customer, companies such as Gamry (USA), Palm Sense (Netherlands) and Metrohm (Netherlands) have designed tools for measuring electrochemical reactions. These electrochemical measurement tools are employed in industry and academia frequently [2][3][4][5][6]. Nevertheless, the potentiostat marketed by any of the abovementioned brands can cost more than $2,000.…”