Using Carbon Paste Electrode Modified with Graphene and Nanodiamond for the Determination of Nimesulide in Biologic and Environmental Samples

Abstract

The present work reports the development and application of a new carbon paste electrode modified with graphene and nanodiamond for the determination of nimesulide in biological and environmental samples. The morphology and electrochemical properties of the carbon nanostructures were characterized by scanning electron microscopy, cyclic voltammetry and electrochemical impedance spectroscopy. The application of the proposed electrochemical sensor led to a significant improvement in the analytical signal and nimesulide oxidation was found to occur at a potential of +0.97 V (vs. Ag/AgCl (3.0 mol L−1 KCl)). The determination of nimesulide was performed based on the application of differential pulse voltammetry, and the results obtained showed a linear concentration range of 0.50–9.0 μmol L−1 (r=0.999) with limit of detection of 15 nmol L−1. The proposed analytical method was successfully applied for the determination of nimesulide in spiked river water, serum and synthetic urine samples, where recoveries close to 100 % were obtained.

Voltammetric determination of hydrogen peroxide at decorated palladium nanoparticles/poly 1,5-diaminonaphthalene modified carbon-paste electrode

“…The limit of detection (LOD) and limit of quantification (LOQ) for H 2 O 2 oxidation by CV were 5.0 and 16.6 nM, respectively, whereas they were 4.0 and 13.3 nM for its reduction, respectively. The LOD and LOQ values were calculated using equations (3.6) and (3.7).LOD=true03σmandLOQ=true010σm where σ is the blank standard deviation and m is the linear's slope [16].…”

“…After the CPE modification with p1,5-DAN, there is a small decrease of ΔE p ∼0. 16 V with E 0 of 0.124 V (figure 2c), whereas the ΔE p decreased to approximately 0.099 V with E 0 of 0.25 V after the deposition of palladium nanoparticles (PdNPs), as shown in figure 2d [48]. ΔE p is inversely proportional to the electron transfer rate [49].…”

“…The limit of detection (LOD) and limit of quantification (LOQ) for H 2 O 2 oxidation by CV were 5.0 and 16.6 nM, respectively, whereas they were 4.0 and 13.3 nM for its reduction, respectively. The LOD and LOQ values were calculated using equations (3.6) where s is the blank standard deviation and m is the linear's slope [16]. These results suggest that the PdNPs/p1,5-DAN/CPE can effectively mediate electron transfer between the electrode and H 2 O 2 , showing clear catalytic activity toward electrochemical redox determination.…”

Voltammetric Determination of Trimethoprim Using a Glassy Carbon Electrode Modified with Printex(6L) Carbon and Gold Nanoparticles

“…Considering its widespread use and the risks it poses to humans and the environment, it is necessary to develop increasingly sensitive, practical and low-cost analytical methods for the determination and/or monitoring of TMP in environmental and biological samples. In this sense, electrochemical sensors stand out for their chemical and physical characteristics, in addition to the possibility of modification, which in turn can further increase their sensitivity and/or selectivity [8][9][10].…”

Voltammetric Sensing of Nifedipine Using a Glassy Carbon Electrode Modified with Carbon Nanofibers and Gold Nanoparticles

“…In recent decades, carbon-based materials have garnered significant attention due to their structural and morphological properties [ 13 , 14 , 15 ]. Those materials have active centers that generate faradaic and reversible oxidation and reduction reactions originating from interactions between an ionic solution and carbon [ 16 ].…”