Simultaneous determination of paracetamol and neurotransmitters in biological fluids using a carbon paste sensor modified with gold nanoparticles

Abstract

A promising electrochemical sensor was developed by electrodeposition of gold nanoparticles on a carbon paste (CP) electrode. This sensor electrode (CPE-Au nano ) was used to determine paracetamol (ACOP) and some neurotransmitters, such as dopamine (DA), epinephrine (EP), norepinephrine (NP), levodopa (L-DOPA) and serotonin (5-HT). Cyclic and differential pulse voltammetry studies indicated that the oxidation of paracetamol at the electrode surface proceeded through a two electron reversible step and was fundamentally controlled by adsorption. Further modification of the sensor by mixing the CPE-Au nano with Nafion Ò showed good sensitivity and effectively resolved the overlapping anodic peaks of these neurotransmitters (NTs) with ACOP. Also, the interfering effect of physiologically common interferences, namely ascorbic acid (AA) and uric acid (UA), on the current response of paracetamol has been studied. Nafion Ò proved to increase the sensitivity of the current signal of the sensor for the oxidation of the compounds studied. Paracetamol gave a well defined oxidation peak at 430 mV in pH 7.4, which was used to quantitate the drug in the two ranges of 50 nM-50 mM and 90-270 mM with a detection limit of 7.7 nM and 28 nM, respectively. The procedure was successfully validated for the assay of paracetamol in pharmaceutical formulations. The applicability of the developed method to determine the drug in human urine samples is also illustrated.

Novel sensor based on carbon paste/Nafion® modified with gold nanoparticles for the determination of glutathione

“…Electrochemical methods, however, present the advantages of simplicity, high sensitivity, low expense, and ease of miniaturization. Particularly, chemically modified electrodes [26][27][28][29][30] are contributing decisively for this purpose. A wide variety of compounds has been incorporated to the electrode as electron transfer mediators for electrooxidation of GSH, for example, TTF-TCNQ [31], abrasive of multiwall carbon nanotubes [32], enzymes [33,34], indium hexacyanoferrate [35], Ru complexes [36], and cobalt phthalocyanine [37].…”

Electroanalysis of Benazepril Hydrochloride Antihypertensive Drug Using an Ionic Liquid Crystal Modified Carbon Paste Electrode

“…Adsorption of surfactants on electrodes and solubilization of electrochemically active compounds in micellar aggregates significantly change the redox potential, charge transfer and diffusion coefficients of electrode processes, as well as the change in the stability of electro-generated intermediates and electrochemical products [42][43][44]. Sodium dodecyl sulfate (SDS) showed a noticeable effect for enhancing preconcentration/accumulation of analyte at the surface which leads to faster electron charge transfer.…”

Multi-walled Carbon Nanotubes/Graphite Nanosheets Modified Glassy Carbon Electrode for the Simultaneous Determination of Acetaminophen and Dopamine

“…They include multi-walled carbon nanotubes modified glassy carbon electrode (MWCNTs/ GCE), 9 nano-TiO2/polymer coated GCE, 10 Ruthenium RedMWCNTs modified GCE 11 and gold nanoparticles modified carbon paste electrode. 12 Carbon materials are widely used in electroanalysis due to their considerable electrocatalytic activity. 13 Possessing high specific surface area and excellent electrical conductivity, MWCNTs have been widely employed for the construction of electrochemical sensors to improve analytical responses.…”