A Multiwall Carbon Nanotubes Paste Electrode as a Sensor and Ferrocenemonocarboxylic Acid as a Mediator for Electrocatalytic Determination of Isoproterenol

摘要

A ferrocenemonocarboxylic acid modified carbon nanotubes paste electrode (FMAMCNTPE) wasconstructed and used as a fast and sensitive tool for the determination of isoproterenol (ISPT) at tracelevel. It has been shown by direct current cyclic voltammetry, double step chronoamperometry andelectrochemical impedance spectroscopy (EIS) that this modified electrode can catalyze the oxidationof ISPT in aqueous solution. The kinetic parameters of the system including electron transfercoefficient, and rate constant for the chemical reaction between ISPT and the redox sites inFMAMCNTPE were also determined using the electrochemical approaches. In addition, differentialpulse voltammetry (DPV) was used for quantitative analysis. DPV showed wide linear dynamic range (0.5 50.0 ol L ISPT) with a detection limit of 0.2 mol L ISPT. The relative standard deviation (RSD%) for ten successive assays of 5.0 ol L ISPT was 1.9%. Finally, this method wasalso examined as a selective, simple and precise electrochemical sensor for the determination of ISPTin real samples such as drug and urine.