The Bi-Disc Glassy Carbon Electrode for Determination of Vitamin K2 (Menaquinone) Using Stripping Voltammetry

Abstract

This paper presents a new type of the working electrode -bi-Disc Glassy Carbon Electrode (b-DGCE). An innovative design of the electrode surface consists of two glassy carbon discs (φ = 1.0 mm) symmetrically placed on the lateral surface of the guidewire formed with chemically resistant resin. The results obtained during characterization of the electrode, conducted by electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV), were consistent with the reversible reaction theory. The b-DGCE was constructed and used as a working electrode for determination of vitamin K2 (VK2) by the differential pulse adsorptive stripping voltammetry (DP AdSV). The electrochemical behavior of VK2 on the b-DGCE was investigated. Parameters affecting the stripping performance, such as composition and concentration of the supporting electrolyte as well as several key instrumental parameters were investigated and optimized. Under the optimized experimental conditions, a linear voltammetric response was received for VK2 in the concentration range from 0.06 to 0.55 mg•L −1 with limit of detection (LoD) of 0.017 for cathodic and 0.021 mg•L −1 for anodic scans, for a short accumulation time of 10 s. Repeatability of the method, expressed as RSD (n = 5) was 2.12 and 1.37 mg•L −1 for cathodic and anodic scans, respectively.

Review—Voltammetric Sensors with Laterally Placed Working Electrodes: A Review

“…16,17 Application of voltammetry allows significant reduction of the amount of the used harmful chemical reagent, but the use of mercury induces, that these methods are not complaisant with the principles of Green Chemistry. 18 Increased risk attributable to the use, handling and disposal of metallic mercury and its salts needed for mercury film generation limits the use of mercury in analytical practice. 19 It is also the driving force in a search for alternative sensors, which would utilize mercury in an infinitesimal amount or in a safe form of an amalgam.…”

“…They represent the most immensely developed group of working electrodes and involve the use of modified CPEs, nanoparticle modified SPEs, zeolites, bimetal configurations, antibodies and many others. 13,18,25,26,31 Profound consideration of the sensors with working electrode placed on the lateral side of the cylindrical electrode body, both on the inner or external walls, is presented herein. The basic construction of this type is composed of a metallic conductor immersed in glass or Teflon® tube, towards which the diffusion is described by Eq.…”

Fast and reliable voltammetric determination of menaquinone (vitamin K2) produced in-vitro by Bacillus subtilis cultures

“…1) was exploited as the analytical signal. The starting point for the optimization are the conditions reported by Takamura [24] and Jedlińska [23]. In this work, the optimization was performed in the supporting electrolyte enriched with VK 2 to give the concentration of 2 µg L − 1 , both in the presence and absence of 50 µL TSB breeding medium.…”

“…In our opinion, voltammetric techniques are de nitely more attractive due to their sensitivity, often not possible to obtain using HPLC methods, simplicity, low costs of the equipment and single analysis, short time of analysis (approx. 20-30 min), reduction of the reagents used during the measurements and sample preparation step, which leads to adapting the method to the green analytical chemistry standards [21]- [24].…”

Fast and reliable voltammetric determination of menaquinone (vitamin K2) produced in vitro by Bacillus subtilis cultures

“…In our opinion, voltammetric techniques are definitely more attractive due to their sensitivity, often not possible to obtain using HPLC methods, simplicity, low costs of the equipment and single analysis, short time of analysis (approx. 20-30 min), and reduction of the reagents used during the measurements and sample preparation step, which leads to adapting the method to the green analytical chemistry standards [26][27][28][29].…”