Electrochemical determination of glutathione in hemolysed erythrocytes

Abstract

The physiological significance of determining glutathione (GSH) and its oxide form is obvious from their applications in clinical practices such as diagnostic experiments for diabetes, Parkinson's disease, and cancers. Such an important detemination still needs the development of certain experimental procedures that are easy, fast, and cheap enough to implement. These procedural advantages can be provided through electrochemical methods. Therefore, in this study, at the surface of a glassy carbon electrode (GCE), a composite of functionalized multi-walled carbon nanotubes (MWCNTs) and formazon was used as a mediator to determine GSH electrochemically. The results indicated that this modified GCE is electrocatalytically very active for glutathione oxidation. Several techniques including cyclic voltammetry (CV), scanning electron microscopy, and differential pulse voltammetry (DPV) were used to characterize the electrode. Also, such kinetic parameters as the charge transfer rate constant and the transfer coefficient were calculated. In optimized conditions, there was a linear relationships between the DPV peak current of GSH oxidation and GSH concentration in the ranges of 1.0-100.0 and 100.0-800.0 µM at pH 7.0. As for the detection limit, it was found to be 0.73 µM. Once put to practice, the devised method proved to be capable of measuring GSH in blood samples.

Electrochemical approaches based on micro- and nanomaterials for diagnosing oxidative stress

“…The detection limit and linear range of GSH and GSSG are 1.2, 1.1 nM, and 2.3-1197.4, 2.4-1248.3nM, respectively. The analytical parameters of some other electrochemical sensing or biosensing devices for GSH [128][129][130][131][132][133][134][135][136][137][138][139][140] are listed in Table 4 (see more comprehensive list in Table S4 in SI).…”

A green approach for metoclopramide quantification in pharmaceutical products. New HPLC and spectrophotometric methods

“…The physicochemical properties of Metoclopramide Analytical methods previously published for the quantification of metoclopramide in bulk [13,14,15], pharmaceutical dosage forms [16,17,18], and biological fluids were scanned in the literatüre [19,20,21]. Spectrophotometric [22,23,24], high-performance liquid chromatographic [25,26,27], and liquid chromatographic coupled with tandem mass spectrometry (LC-MS/MS) [28] methods were reported for determination of metoclopramide in pharmaceutical dosage forms and biological fluids were developed.…”

Novel Green Method for the Spectrophotometric Determination of Metoclopramide Hydrochloride in Pharmaceutical Formulations

“…A survey of the literature reported that metoclopramide hydrochloride was estimated under optimal conditions by different spectrophotometric methods and using various chemical reagents, such as: azo-dye coupling (3)(4)(5)(6)(7)(8)(9)(10)(11), oxidative coupling (12)(13)(14), Schiff base Reaction (15), and charge transfer complex (16). A number of researchers were able to estimate (MCP.H) by using other spectrophotometric methods such as UV, colored ion-pair complex, oxidation, reduction reaction and nucleophilic substitution reaction, in the presence of chemical reagents and under various optimal condition (17)(18)(19)(20), diverse HPLC methods (21)(22)(23)(24)(25), FIuorescent analysis (26), and Glassy carbon electrode (GCE) were also used (27). Currently, the recent methodological development in analytical chemistry gave rise to a plethora of improved and durable versions of an environmentally friendly approach (28), some of these concepts are safe compounds (29).…”