Electrochemically pretreated screen-printed carbon electrodes for the simultaneous determination of aminophenol isomers

This study reports that disposable, electrochemically pretreated screen-printed carbon electrodes (SPCE*) can be employed for the simultaneous determination of aminophenol isomers in aqueous buffer solution. In sharp contrast to untreated SPCE, voltammetric studies indicate that the oxidation peak potential of each analyte in an aminophenol isomer mixture may be separated at the activated SPCE*. The individual oxidation peak currents are greatly increased by first-order derivative techniques. All experimental parameters were optimized to improve responses. The derivative oxidation peak currents is proportional to the concentration of isomer over the range from 0.2 to 100 μM for 2-aminophenol (2AP), from 3.0 to 200 μM for 3-aminophenol (3AP), and from 0.2 to 200 μM for 4-aminophenol (4AP), with detection limits of 0.07, 0.16 and 0.05 μM, respectively. The proposed methods have excellent analytical characteristics that include ease of handling, high sensitivity, wide linear dynamic range and low detection limits. The assay was applied to the simultaneous determination of aminophenol isomers in river water with good recovery results.