Electrochemical determination of levodopa in the presence of ascorbic acid by polyglycine/ZnO nanoparticles/multi-walled carbon nanotubes-modified carbon paste electrode

Abstract

This work report on electrodeposition of polyglycine microparticles onto zinc oxide (ZnO) nanoparticles/multi-walled carbon nanotube-modified carbon paste electrode surface in order to construction new levodopa (L-dopa) electrochemical sensor. The prepared electrode used for sensitive and selective determination of L-dopa in the presence of ascorbic acid. The electrochemical response of L-dopa on this modified electrode was studied using cyclic voltammetry (CV) and differential pulse voltammetry (DPV) techniques. The effect of various experimental parameters including pH and scan rate on the voltammetric response of L-dopa was investigated. The results show that the process of oxidation of this compound is adsorption controlled. At the optimum conditions, the concentration of L-dopa was determined by differential pulse voltammetry, and a dynamic linear range of 5.0-500.0 μmol L −1 and detection limit of 0.08 μmol L −1 were obtained. The results of pharmaceutical and human urine samples' voltammetric analysis showed that using the proposed method, a precise and sensitive electrochemical determination of L-dopa is feasible.

Electrochemical determination of lead(II) ions in hot spring water based on a multi-walled carbon nanotube-modified glassy carbon electrode

“…However, these composite materials have advantages such as fast preparation and low cost and have thus been applied to lead analysis [13][14][15][16]. The preparation strategy of injectionmolding has been reported in previous studies, in addition to its merits and demerits in the mass production of polymer-based lab-on-a-chip analytical apparatuses [17][18][19]. Additionally, the feasibility of the plastic/carbon fiber composite electrodes in electrochemical analysis has been confirmed in previous literature [20][21][22][23][24].…”

Preparation of MoS2‐graphene Hybrid Nanosheets and Simultaneously Electrochemical Determination of Levodopa and Uric Acid

“…The limit of detection (LOD) of MoS 2 ‐graphene/ITO electrode for LD and UA is 0.3 and 0.4 μM, respectively. It suggests the MoS 2 ‐graphene/ITO electrode shows a higher sensitivity and a lower LOD compared with the other previous electrodes (Table and ) .…”

Highly Sensitive Electrochemical Sensing Platform for the Detection of L-dopa Based on Electropolymerizing Glutathione Disulfide and Multi-walled Carbon Nanotube-modified Electrodes

“…5A(d)), hinting the electron transfer was promoted by the synergistic effect of MWCNTs and PGSSG. 27 The kinetics process of the redox of L-dopa on the surfaces of the modified electrode was further investigated via CV at scan rates from 25 to 250 mV s -1 . The peak currents increased with the increase of scan rates, and the results showed the linear relationship between peak currents (I pa or I pc ) and the square-root of scan rate (n 1/2 ) (Fig.…”