@article{3072694, title = "A potentiostat featuring an integrator transimpedance amplifier for the measurement of very low currents - Proof-of-principle application in microfluidic separations and voltammetry", author = "Koutilellis, G.D. and Economou, A. and Efstathiou, C.E.", journal = "Review of Scientific Instruments", year = "2016", volume = "87", number = "3", publisher = "American Institute of Physics Inc.", issn = "0034-6748, 1089-7623", doi = "10.1063/1.4942915", keywords = "Capillary electrophoresis; Microfluidics; Operational amplifiers; Voltage regulators, Amperometric detection; Cell configurations; Design and construction; Feedback resistors; Integration approach; Microfluidic separations; Proof of principles; Voltammetric techniques, Cyclic 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. © 2016 AIP Publishing LLC." }