Analytical chemistry
Roghiyeh Pourghobadi; Mohammad Reza Baezzat
Abstract
The present study examines a new dopamine sensor based on Alumina nanoparticles modified carbon paste electrode (Al2O3NPsCPE). Moreover, the present study focuses on the electrochemical act of the Al2O3NPsCPE for the detection of dopamine by cyclic voltammetry (CV) and differential pulse voltammetry ...
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The present study examines a new dopamine sensor based on Alumina nanoparticles modified carbon paste electrode (Al2O3NPsCPE). Moreover, the present study focuses on the electrochemical act of the Al2O3NPsCPE for the detection of dopamine by cyclic voltammetry (CV) and differential pulse voltammetry (DPV). There is also a focus on the specification of the prepared modified electrode by electrochemical impedance spectroscopy (EIS) and scanning electron microscopy (SEM), and there is a discussion on the influence of some experimental variables such as carbon paste composition, laboring solution pH, scan rate and possible interferences. The present study obtained a well-defined redox peak of dopamine (DA) on the Nano- Alumina/CPE at Epa=173mV and Epc=112mV, respectively. The obtained response of the sensor was linear under the optimal conditions of the catalytic peak current, in the range of 8.0-330.0 µM, and the detection limit was 2.1 µM (S/N=3) for dopamine. The proposed sensor exhibited a high sensitivity, an excellent reproducibility, good selectivity, and it was successfully used in the determination of dopamine injection samples.

Analytical chemistry
Hamid Reza Zare-Mehrjardi
Volume 6, Issue 3, pp. 218-324, Serial No. 20 , July 2018, , Pages 300-311
Abstract
In this paper, the carbon paste electrode (CPE) is modified using an ionic liquid (1-Butyl-3-methylimidazolium tetrafluoroborate, [BMIM]BF4) and the cis-dioxo-bis[3-methoxy-2,2-dimethylpropanediamine] molybdenum(VI) complex (cis-[Mo(O)2L]). In order to study of the electrochemical behavior of ascorbic ...
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In this paper, the carbon paste electrode (CPE) is modified using an ionic liquid (1-Butyl-3-methylimidazolium tetrafluoroborate, [BMIM]BF4) and the cis-dioxo-bis[3-methoxy-2,2-dimethylpropanediamine] molybdenum(VI) complex (cis-[Mo(O)2L]). In order to study of the electrochemical behavior of ascorbic acid (AA) and dopamine (DA) at the surface of the prepared CPEs, the differential pulse and cyclic voltammetric methods (DPV and CV) were used. The percent of the [BMIM]BF4 in the matrix of the modified CPE is optimized, and then the effect of the pH of the buffered solution on the electrode response and the resolution between the anodic peaks of AA and DA is studied by CV and DPV. These results reveal that by application of the modified CPE a peak resolution about 325mV is obtained for AA and DA and the linear range for AA and DA in buffered solutions of pH 5.0 is acquired in the range from 5.0×10−7 to 1.0×10−3 M. The respective limits of detection (S/N = 3) were 1×10−7 M and 2×10−7 M for DA and AA, respectively. Surface regeneration and the very easy preparation of the modified CPE together with the very good peak resolution and sub-micromolar detection limits designate the prepared CPE in this work appropriate for simultaneous voltammetric determination of DA and AA.
