A new strategy for the selective determination of glutathione in the presence of nicotinamide adenine dinucleotide (NADH) using a novel modified carbon nanotube paste electrode
Graphical abstract
Highlights
► A new modified electrode for the determination of glutathione and NADH is described. ► Dinitrobenzamide derivative incorporated with MWCNTs used to prepare the electrode. ► Glutathione and NADH could be detect as low as 0.05 μmol L−1 and 1.0 μmol L−1. ► Simultaneous or independent measurements of the two analytes are possible.
Introduction
Thiol-containing compounds such as glutathione (GSH) play an important role in many biochemical processes [1]. GSH is a nonprotein tripeptide composed of amino acids, which are synthesized in two steps: catalysis by γ-glutamyl cysteine synthetase and GSH synthesis followed by degradation into cysteinyl-glycine by γ-glutamyl trans peptidase [2]. GSH as a major intracellular thiol compound plays an important role in many biological processes such as intracellular reduction–oxidation metabolic cycles, transportation, protein synthesis, catabolism, and metabolism [3], [4]. Measurement of free glutathione in blood samples indicates the status of cells in relation to their protective role against oxidative and free radical-mediated cell injury. Moreover, GSH measurement is important for the diagnosis of c-glutamyl cycle disorders [5]. It is, therefore, essential to have a fast and sensitive method for the determination of GSH. A number of methods have been proposed for the determination of GSH including titrimetry [6], spectrophotometry [7], [8], spectrofluorimetry [9], high performance liquid chromatography (HPLC) [10], [11], [12], capillary zone electrophoresis [13], [14], and proton nuclear magnetic resonance (1H NMR) [15], [16] as well as enzymatic [17] and electrochemical methods [18], [19], [20], [21].
NADH is an important coenzyme produced in vivo during dehydrogenase-based enzymatic reactions. NADH plays an important role in the generation of ATP, the body's energy currency, and has been found to be deficient in several age-related degenerative diseases. Uncontrolled studies in Europe have found NADH beneficial for patients suffering from Parkinson's disease, Alzheimer's disease, and depression. The determination of NADH is interesting because the pyridine nucleotides NAD and NADP are ubiquitous in all living systems and are required for the reactions of more than 400 oxido-reductase compounds [22].
Recent studies have shown that NADH is needed for the regeneration of glutathione after its oxidization. If NADH levels are depleted, glutathione levels may also fall. Thus, supplementation with NADH may also help restore glutathione to its active form [22]. Therefore, simultaneous and selective determination of these compounds in biological samples is very important. To the best of our knowledge, there is no report in the literature on the simultaneous electrocatalytic determination of GSH and NADH, using modified multiwall carbon nanotube paste electrodes.
Increasing attention has been paid to the use of carbon nanotubes as a promising electrode material due to their unique properties [23], [24], [25], [26], [27], [28], [29], [30]. The use and performance of CNT paste electrodes prepared by thoroughly mixing multiwall carbon nanotubes (MWCNTs) and mineral oil has already been reported in the literature [30], [31], [32], [33], [34], [35], [36], [37]. The resulting electrodes, modified with a proper mediator, showed very good electrocatalytic activity toward oxidation of biological compounds [38], [39], [40], [41].
In this study, the voltammetric and electrochemical impedance spectroscopic techniques were used at pH 7.0 to demonstrate the electrochemical behavior of GSH and NADH on the multiwall carbon nanotube paste electrode modified with N-(3,4-dihydroxyphenethyl)-3,5-dinitrobenzamide as a mediator (DHPB/CNTPE). The proposed method was used for the determination of GSH in pharmaceutical, hemolysed erythrocyte, and urine samples. The results show that the proposed method is highly selective and sensitive for the determination of GSH and NADH, outperforming any electrochemical method so far reported in the literature. Table 1 shows the figures of merit of the proposed electrochemical sensor with the papers reported on the voltammetric detection of GSH. The main advantages of the proposed sensor include its sensitivity and ability to detect GSH and NADH individually and/or simultaneously.
Section snippets
Chemicals
All chemicals used were of analytical reagent grade purchased from Merck (Darmstadt, Germany) unless otherwise stated. Doubly distilled water was used throughout.
A 1.0 × 10−2 mol L−1 GSH solution was prepared daily by dissolving 0.30 g glutathione in water and diluted the solution to 100 mL with water in a 100-mL volumetric flask. The solution was kept in a refrigerator at 4 °C and in dark. More dilute solutions were prepared by serial dilution with water.
A 1.0 × 10−2 mol L−1 NADH solution was prepared
Electrocatalytic oxidation of GSH
Fig. 1 displays typical morphologies of CPE (A) and DHPB/CNTPE (B). It can be seen that isolated layers of irregular flakes of graphite powder are present on the surface of CPE (Fig. 2A). Upon addition to the carbon paste matrix, the multiwall carbon nanotubes clearly disperse on the electrode with a special three-dimensional structure (Fig. 1B). Fig. 1C shows a higher magnification section of Fig. 1B, demonstrating the dispersion of MWCNTs on the surface of the graphite powder.
GSH is an
Conclusion
This study describes the construction of a DHPB/CNTPE and its application for the simultaneous determination of GSH and NADH. The result showed that oxidation of GSH is catalyzed by DHPB at pH 7.0, whereas the peak potential of GSH is shifted by 430 mV to a less positive potential at the surface of DHPB/CNTPE. A peak potential difference of about 330 mV between GSH and NADH was detected, which was large enough to determine GSH and NADH individually and simultaneously. In addition, this modified
Acknowledgements
The authors wish to thank Isfahan University of Technology (IUT) Research Council and Center of Excellence in Sensor and Green Chemistry for their support.
References (49)
- et al.
Enzymatic rotating biosensor for cysteine and glutathione determination in a FIA system
Talanta
(2006) - et al.
Spectrophotometric determination of glutathione and of its oxidation product in pharmaceutical dosage forms
J. Pharm. Biomed. Anal.
(1991) - et al.
Direct spectrofluorimetric determination of glutathione in biological samples using 5-maleimidyl-2-(m-methylphenyl) benzoxazole
Anal. Chim. Acta
(2002) - et al.
Determination of reduced and oxidized glutathione in biological samples using liquid chromatography with fluorimetric detection
J. Pharm. Biomed. Anal.
(2007) - et al.
Quantification of glutathione and glutathione disulfide in human plasma and tobacco leaves by capillary electrophoresis with laser-induced fluorescence detection
Talanta
(2005) - et al.
Determination of glutathione in intact and hemolyzed erythrocytes by titration with tert-butyl hydroperoxide with end point detection by 1H nuclear magnetic resonance spectrometry
Anal. Chim. Acta
(1988) - et al.
Determination of glutathione in hemolysed erythrocyte by flow injection analysis with chemiluminescence detection
J. Pharm. Biomed. Anal.
(2008) - et al.
Simultaneous electrochemical determination of glutathione and tryptophan on a nano-TiO2/ferrocene carboxylic acid modified carbon paste electrode
Sens. Actuators B
(2009) - et al.
Electrocatalytic oxidation of reduced nicotinamide adenine dinucleotide (NADH) at thick-film gold electrodes
J. Electroanal. Chem.
(1995) - et al.
Simultaneous determination of adenosine and inosine using single-wall carbon nanotubes modified pyrolytic graphite electrode
Talanta
(2008)
Voltammetric determination of cefixime in pharmaceuticals and biological fluids
Anal. Biochem.
Modified multiwall carbon nanotubes paste electrode as a sensor for simultaneous determination of 6-thioguanine and folic acid using ferrocenedicarboxylic acid as a mediator
J. Electroanal. Chem.
Sensors for 5-hydroxytryptamine and 5-hydroxyindole acetic acid based on nanomaterial modified electrodes
Sens. Actuators B
Simultaneous determination of N-acetylcysteine and acetaminophen by voltammetric method using N-(3,4-dihydroxyphenethyl)-3,5-dinitrobenzamide modified multiwall carbon nanotubes paste electrode
Sens. Actuators B
Synthesis and characterization of alumina-coated carbon nanotubes and their application for lead removal
J. Hazard. Mater.
Voltammetric biosensors for the determination of paracetamol at carbon nanotube modified pyrolytic graphite electrode
Sens. Actuators B
Novel surfactant selective electrochemical sensors based on single walled carbon nanotubes
J. Mol. Liq.
Highly sensitive voltammetric sensor based on catechol-derivative-multiwall carbon nanotubes for the catalytic determination of captopril in patient human urine samples
Colloids Surf. B
Poly(3-methylthiophene)/palladium sub-micromodified sensor electrode. II. Voltammetric and EIS studies, and analysis of catecholamine neurotransmitters, ascorbic acid and acetaminophen
Talanta
Determination of isoproterenol and uric acid by voltammetric method using carbon nanotubes paste electrode and p-chloranil
Colloids Surf. B
Hematoxylin multi-wall carbon nanotubes modified glassy carbon electrode for electrocatalytic oxidation of hydrazine
Electrochim. Acta
Application of modified multiwall carbon nanotubes paste electrode for simultaneous voltammetric determination of morphine and diclofenac in biological and pharmaceutical samples
Sens. Actuators B
Quantitation of sulfhydryls DTNB, Ellman's reagent
Arch. Biochem. Biophys.
Electrochemical oxidation of glutathione at well-aligned carbon nanotube array electrode
Electrochim. Acta
Cited by (98)
Sudan I monitoring as a hazardous azo dye using an electroanalytical tool amplified with NiO/SWCNTs-ionic liquid catalysts
2022, ChemosphereCitation Excerpt :Improving surface, thermal, electrical, mechanical, and catalytic properties are the most direct effects of nanotechnology in engineering sciences (Akça et al., 2021; Babu et al., 2021; Cherian et al., 2021; Luo et al., 2021; Jamila et al., 2022; Mansur et al., 2022; Mubashir et al., 2022). Meanwhile, using nanomaterials with high electrical conductivity to prepare electrochemical sensors is also attractive (Ensafi et al., 2010, 2013; Vatandost et al., 2020; Ghalkhani et al., 2022; Zhang et al., 2022). Electrochemical sensors have taken a new step forward in their development due to the utilization of nanomaterials with high electrical conductivity and the capacity to be modified with biomaterials (Karimi-Maleh et al., 2012; Mpelane et al., 2022; Tabrizi et al., 2022).
A polypyrrole/GO/ZnO nanocomposite modified pencil graphite electrode for the determination of andrographolide in aqueous samples
2022, Alexandria Engineering Journal