Carbon Materials in Electroanalysis of Preservatives: A Review

Electrochemical sensors in electroanalysis are a particularly useful and relatively simple way to identify electroactive substances. Among the materials used to design sensors, there is a growing interest in different types of carbon. This is mainly due to its non-toxic properties, low cost, good electrical conductivity, wide potential range, and the possibility of using it in both aqueous and nonaqueous media. The electrodes made of carbon, and especially of carbon modified with different materials, are currently most often used in the voltammetric analysis of various compounds, including preservatives. The objective of this paper is to present the characteristics and suitability of different carbon materials for the construction of working electrodes used in the voltammetric analysis. Various carbon materials were considered and briefly discussed. Their analytical application was presented on the example of the preservatives commonly used in food, cosmetic, and pharmaceutical preparations. It was shown that for the electroanalysis of preservatives, mainly carbon electrodes modified with various modifiers are used. These modifications ensure appropriate selectivity, high sensitivity, low limits of detection and quantification, as well as a wide linearity range of voltammetric methods of their identification and determination.

Detection of Organic Additives in Copper Plating Bath Using Voltammetric Methods That Involve a Screen-printed Nano-Au Electrode

Three electrochemical methods used to detect organic additives, A, B and C, in acidic plating baths. Cyclic voltammetric stripping (CVS) is used in industry to detect the concentration of organic additives indirectly by measuring the effect of commercial organic additives on the rate of copper deposition. This study directly determines the concentration of organic additives on a screen-printed nano-Au electrode at high potential using three different electrochemical methods: linear scanning voltammetry (LSV), differential pulse voltammetry (DPV) and square wave voltammetry (SWV). The results show that the response currents for the three electrochemical methods exhibit a linear relationship with the concentration of organic additives. The nano-Au electrode is the most sensitive device for the detection of organic additive B using LSV.

Generic sensor platform based on electro-responsive molecularly imprinted polymer nanoparticles (e-NanoMIPs)

The present research describes the design of robust electrochemical sensors based on electro-responsive molecularly imprinted polymer nanoparticles (e-MIPs). The e-MIPs, tagged with a redox probe, combine both recognition and reporting functions. This system replaces enzyme-mediator pairs used in traditional biosensors. The analyte recognition process relies on the generic actuation phenomenon when the polymer conformation of e-MIPs is changing in response to the presence of the template analyte. The analyte concentration is measured using voltammetric methods. In an exemplification of this technology, electrochemical sensors were developed for the determination of concentrations of trypsin, glucose, paracetamol, C4-homoserine lactone, and THC. The present technology allows for the possibility of producing generic, inexpensive, and robust disposable sensors for clinical, environmental, and forensic applications.