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Detection Techniques Used By Capillary Electrophoresis, Flow Analysis, And Liquid Chromatography

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Amperometric detection (AD) For more see journals 109. Amperometric detection (AD) is the widely reported electrochemical detection technique in capillary electrophoresis, flow analysis, and liquid chromatography [Art. No. 108]. This technique carried out by supplying a constant potential to the working electrode and resulting current measured as a function of time. At the surface of the working electrode, the redox reaction of the analytes takes place by the application of potential, whereas output current is proportional to the analytes concentration. Furthermore, the response of current is directly proportional to the number of analyte moles that oxidize or reduce at the working electrode surface as given by Faraday’s law: I_t=dQ/dt=nF dN/dt where I_t is the yield current at working electrode surface at given time t, Q is the charge at the working electrode surface, t is is the time, n is the number of electrons transferred per mole of analyte, F is the Faraday constant (96485 C/mol), and N is number of moles of analyte oxidized or reduced [33: Art. No. 101]. Advantages There are some unique advantages make amperometric technique more popular such as higher sensitivity, very good selectivity in the direction of electroactive compounds, simple instrumentation easy to handle and economical [Art. No. 105], minimal contribution of background current, and easy to operate [Art. No. 108]. Voltammetry For more see

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