Voltammetric Determination of Homocysteine Using Multiwall Carbon Nanotube Paste Electrode in the Presence of Chlorpromazine as a Mediator

Abstract

We propose chlorpromazine (CHP) as a new mediator for the rapid, sensitive, and highly selective voltammetric determination of homocysteine (Hcy) using multiwall carbon nanotube paste electrode (MWCNTPE). The experimental results showed that the carbon nanotube paste electrode has a highly electrocatalytic activity for the oxidation of Hcy in the presence of CHP as a mediator. Cyclic voltammetry, double potential step chronoamperometry, and square wave voltammetry (SWV) are used to investigate the suitability of CHP at the surface of MWCNTPE as a mediator for the electrocatalytic oxidation of Hcy in aqueous solutions. The kinetic parameters of the system, including electron transfer coefficient, and catalytic rate constant were also determined using the electrochemical approaches. In addition, SWV was used for quantitative analysis. SWV showed wide linear dynamic range (0.1–210.0 μM Hcy) with a detection limit of 0.08 μM Hcy. Finally, this method was also examined as a selective, simple, and precise electrochemical sensor for the determination of Hcy in real samples.

Electrocatalytic oxidation and determination of homocysteine at carbon nanotubes modified paste electrode using dopamine as a mediator

“…8 The voltammetric response of HCy at MWCNTPE was investigated in presence and absence of DP in pH 5.0 buffer solution using cyclic voltammetry at a scan rate of 20 mV s −1 . The recorded cyclic voltammograms of HCy in the absence of DP did not show a significant redox peak for HCy (Fig.…”

“…In addition, small metabolic changes of HCy affect many physiological concentrations. 7,8 According to many researches, elevated plasma HCy concentrations are known to be a factor implicated in the appearance and progression of various diseases, such as coronary artery and cerebro vascular disease. 4,9,10 To date, due to the importance of the determination of HCy, different techniques have been employed its measurement.…”

A sensitive electrochemical sensor for hydroxylamine determination: Using multiwall carbon nanotube paste electrode (MWCNTPE) and promazine hydrochloride as homogenous mediator

“…Promazine is an older drug for schizophrenia, and still prescribed belong newer drugs. Ensafi and coworkers [12][13], Gholami-Orimi and coworkers [14], report redox activities of chlorpromazine, as a derivative of promazine, toward electro oxidation of some substance such as glutathione, captopril and homocysteine, respectively. In the present study, we proposed promazine hydrochloride as a homogeneous mediator for the rapid, simple, sensitive, and highly selective voltammetric determination of hydroxylamine on the surface of a multiwall carbon nanotubes paste electrode (MWCNTPE).…”

The effect of carbon nanotubes as a support on morphology and size of silver nanoparticles

“…Therefore, the number of studies on different parameters is increased. Meanwhile, the exceptional electrical, chemical, and mechanical characters [9,10] made carbon nanotubes (CNTs) widely used in the construction of chemical sensors and biosensors [11,12], especially in the field of supporting materials [13]. The high surface area of CNTs made it possible to load nanoparticles to enhance their properties [8,[11][12][13].…”

“…Much effort has been made to acquire these hybrid nanomaterials [13]. Many researchers are trying to improve and modify CNT walls to achieve high dispersion of metal nanoparticles on the CNT surface [8,10,11,13,14]. However, there are three problems regarding the application of CNTs as a support for the nucleation of nanoparticles.…”