Rapid Voltammetric Screening Method for the Assessment of Bioflavonoid Content Using the Disposable Bare Pencil Graphite Electrode

Abstract

Hesperidin (HESP) is a plant bioflavonoid found in various nutritional and medicinal products. Many of its multiple health benefits rely on the compound’s antioxidant ability, which is due to the presence of oxidizable hydroxyl groups in its structure. Therefore, the present study aimed to investigate the electrochemical behavior of HESP at a cheap, disposable pencil graphite electrode (PGE) in order to develop rapid and simple voltammetric methods for its quantification. Cyclic voltammetric investigations emphasized a complex electrochemical behavior of HESP. The influence of the electrode material, solution stability, supporting electrolyte pH, and nature were examined. HESP main irreversible, diffusion-controlled oxidation signal obtained at H type PGE in Britton Robinson buffer pH 1.81 was exploited for the development of a differential pulse voltammetry (DPV) quantitative analysis method. The quasi-reversible, adsorption-controlled reduction peak was used for HESP quantification by differential pulse adsorptive stripping voltammetry (DPAdSV). The linear ranges of DPV and DPAdSV were 1.00 × 10−7–1.20 × 10−5 and 5.00 × 10−8–1.00 × 10−6 mol/L with detection limits of 8.58 × 10−8 and 1.90 × 10−8 mol/L HESP, respectively. The DPV method was applied for the assessment of dietary supplements bioflavonoid content, expressed as mg HESP.

Electroanalysis of Naringin at Electroactivated Pencil Graphite Electrode for the Assessment of Polyphenolics with Intermediate Antioxidant Power

“…The tested working electrodes were different hardness, with PGEs of 0.50 mm graphite pencil leads (B, HB and 2B from the brands Laco and Rotring) having the geometrical active surface area (A g ) of 0.1589 cm 2 ; a glassy carbon electrode (GCE) and a Pt electrode with the A g of 0.0700 cm 2 and 0.0314 cm 2 , respectively. Nevertheless, the main working electrode was the PGE, which consisted of 6.00 cm long, commercially available graphite pencil leads cut in half and introduced with the cut edge into a mechanical pencil lead used as a holder; 1.50 cm of the lead remained outside and always only 1.00 cm of this part was immersed in the analyzed solution so that the A g of the electrode was always constant [ 41 ]. The electrical contact was realized by a copper wire soldered on the metallic part of the pencil.…”

“…In recent years PGE gained increasing applicability due to its similar or even better electrochemical characteristics in comparison to other commonly used working electrodes, besides its other inherent economic advantages (cost-effectiveness and easy availability) [ 35 , 36 ]. However, there are few reports using this electrode for the electroanalysis of bioflavonoids [ 34 , 37 , 38 , 39 , 40 , 41 ] which, based on their oxidation potential [ 42 ], are considered to have intermediate antioxidant power (AOP) [ 43 ]. To the best of our knowledge, there is no research that has been conducted on the NG electroanalysis of disposable, bare PGE.…”

Portable Microelectrochemical Sensors for Rapid and Sensitive Determination of Hesperidin in Citrus reticulate ‘Chachi’ Peel

“…In this study, pencil graphite electrodes are recognized as attractive electrode substrates owing to their low cost, simplicity, and commercial availability, and have been used for the detection of different analytes [ 17 ]. For example, several studies have reported the use of pencil graphite electrodes (bare or treated) for the sensitive detection of bioflavonoids such as quercetin [ 18 ], diosmin [ 19 ], and hesperidin [ 20 , 21 ]. Particularly, David et al reported the electrocatalysis of hesperidin at pencil graphite electrodes with different hardness (from 2B to 2H) [ 21 ] although the detailed effects of the surface morphology and the characterization of pencil graphite electrodes on the electrocatalysis of hesperidin remains unclear.…”

“…For example, several studies have reported the use of pencil graphite electrodes (bare or treated) for the sensitive detection of bioflavonoids such as quercetin [ 18 ], diosmin [ 19 ], and hesperidin [ 20 , 21 ]. Particularly, David et al reported the electrocatalysis of hesperidin at pencil graphite electrodes with different hardness (from 2B to 2H) [ 21 ] although the detailed effects of the surface morphology and the characterization of pencil graphite electrodes on the electrocatalysis of hesperidin remains unclear. Furthermore, a portable microelectrochemical sensor based on pencil graphite for rapid bioflavonoids detection has not been previously reported.…”

Recent Developments in Voltammetric Analysis of Pharmaceuticals Using Disposable Pencil Graphite Electrodes

“…A promising approach in pharmaceutical analysis can be the use of electroanalytical techniques, especially due to the fact that they are suitable for miniaturization and portability, thus enabling on-site monitoring. Their efficiency was proven by their extensive use for the detection and quantification of various compounds, with powerful impacts on human health [2][3][4][5] and environment [6][7][8].…”