A new microcomposite with copper(II) complex and carbon paste (CuC/CPE) was developed to determine the uric acid (UA) content in the presence of dopamine (DP) and was characterized via cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and energy dispersive spectroscopy (EDS). The results showed high selectivity for UA compared with DP because the anodic peak currents for DP were near those of a CPE without Cuc and were considerably increased for UA. The UA and DP increases were 86.9 % and 14.3 %, respectively, according to CV and 96.6 % and 25.5 %, respectively, according to square wave voltammetry (SWV) with the CuC/CPE. Moreover, the anodic peak separation for UA and DP was 0.17 V. With optimal parameters (pH, 3.3; adsorption time(tADS), 30 s;adsorption potential (EADS), 0.10 V), the anodic peak currents for UA were proportional to concentrations between 1.6 and 14.4 μmol L−1 using standard solutions with UA concentrations ranging from 8.0–40.5 μmol L−1 and real samples. The UA detection limit was 0.13 μmol L−1. The new sensor was used to determine the UA contentin human urine samples, and the method was checked with a urine chemistry control from Bio-Rad based on human urine spiked with quantities of UA and showed a recovery between 84 % and 106 % at concentrations below 10.0 μmol L−1.
Bibliographical noteFunding Information:
E. N grateful acknowledges the financial support provided by the Universidad de Ibagué. The authors express their thanks to Universidad de los Andes for financial support from the Faculty of Sciences (project no. INV‐2018‐50‐1354) and the Department of Chemistry.
E. N grateful acknowledges the financial support provided by the Universidad de Ibagu?. The authors express their thanks to Universidad de los Andes for financial support from the Faculty of Sciences (project no. INV-2018-50-1354) and the Department of Chemistry.
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- carbon paste
- copper complex
- square wave voltammetry
- uric acid