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Sensor Chemical Reactions in Metal Oxide Nanocomposites

A special issue of International Journal of Molecular Sciences (ISSN 1422-0067). This special issue belongs to the section "Physical Chemistry and Chemical Physics".

Deadline for manuscript submissions: closed (28 February 2022) | Viewed by 52145

Special Issue Editor

N.N. Semenov Federal Research Center for Chemical Physics of RAS, Moscow 119991, Russia
Interests: physico-chemical and electrophysical processes in nanosystems; chemical reactions in solid phase; cryochemical reactions
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Special Issue Information

Dear Colleagues,

In recent years, due to the increase in the content of various harmful impurities in the atmosphere, the number of studies on metal oxide sensors used to detect such impurities has increased significantly. The most common and promising means of detecting harmful and explosive substances in the surrounding atmosphere is semiconductor metal oxide sensors. The detection process is based on the chemical reaction of the analyzed compounds with oxygen chemisorbed on the surface of the semiconductor. As a result of this reaction, electrons captured by the chemisorbed oxygen return to the conduction band of the semiconductor, which leads to an increase in the conductivity of the sensor.

A promising direction for increasing the selectivity and sensitivity of metal oxide sensors is the use of mixed metal oxide systems, which combine metal oxides with various electronic characteristics and chemical properties. Varying the nature and content of components in such systems opens up new possibilities for controlling the intensity and selectivity of the sensory response in the detection of various substances in air. In this regard, the review considers and discusses studies of the structure and sensory properties of nanostructured binary composites consisting of semiconductor metal oxides of various natures as well as various physicochemical processes, including chemical reactions that occur when such sensors detect reducing gases.

Prof. Dr. Leonid Trakhtenberg
Guest Editor

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Published Papers (4 papers)

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Research

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15 pages, 2537 KiB  
Article
Determination of Diosmin in Pharmaceutical Products with Chemically Modified Voltammetric Sensors
by Ramona Oana Gunache (Roșca) and Constantin Apetrei
Int. J. Mol. Sci. 2021, 22(14), 7315; https://0-doi-org.brum.beds.ac.uk/10.3390/ijms22147315 - 07 Jul 2021
Cited by 5 | Viewed by 2267
Abstract
In this paper, the electrochemical behavior of two types of sensors based on modified screen-printed electrodes (one screen-printed electrode based on carbon (SPCE) and another screen-printed electrode modified with Prussian Blue (PB/SPCE)) was studied with the aim of sensitive detection of diosmin, an [...] Read more.
In this paper, the electrochemical behavior of two types of sensors based on modified screen-printed electrodes (one screen-printed electrode based on carbon (SPCE) and another screen-printed electrode modified with Prussian Blue (PB/SPCE)) was studied with the aim of sensitive detection of diosmin, an active pharmaceutical compound from the class of flavonoids. The scan electron microscopy technique was used for the morphological characterization of PB/SPCE. The preliminary analysis assessed the electrochemical behavior of SPCE and PB/SPCE in KCl solution and in a double solution of potassium ferrocyanide–potassium chloride. It was shown that the active area of PB/SPCE is superior to the one of SPCE, the greater sensitivity being related with the presence of the electroactive modifier. Similarly, in the case of diosmin detection, the PB/SPCE sensor detect more sensitivity the diosmin due to the electrocatalytic effect of PB. From the study of the influence of reaction rate on the sensor’s electrochemical response, it was shown that the detection process is controlled by the adsorption process, the degree of surface coverage with electroactive molecules being higher in the case of PB/SPCE. From the PB/SPCE calibration curve, it wasdetermined that it has high sensitivity and low detection and quantification limit values (limit of detection 5.22 × 10−8 M). The applicability of the PB/SPCE sensor was confirmed by sensitive analysis of diosmin in pharmaceutical products. The voltammetric method is suitable for the detection and quantification of diosmin in pharmaceutical products. The method is simple, accurate, and quick and can be used in routine analysis in the examination of the quality of pharmaceutical products and other types of samples. Full article
(This article belongs to the Special Issue Sensor Chemical Reactions in Metal Oxide Nanocomposites)
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Review

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24 pages, 4124 KiB  
Review
A Review on Electrochemical Sensors and Biosensors Used in Chlorogenic Acid Electroanalysis
by Irina Georgiana Munteanu and Constantin Apetrei
Int. J. Mol. Sci. 2021, 22(23), 13138; https://0-doi-org.brum.beds.ac.uk/10.3390/ijms222313138 - 05 Dec 2021
Cited by 20 | Viewed by 2883
Abstract
Chlorogenic acid (5-O-caffeoylquinic acid) is a phenolic compound from the hydroxycinnamic acid family. Epidemiological, biological, and biochemical studies concur to support the beneficial role of chlorogenic acid in human health, along with other dietary phenolic compounds. Thus, chlorogenic acid has been reported to [...] Read more.
Chlorogenic acid (5-O-caffeoylquinic acid) is a phenolic compound from the hydroxycinnamic acid family. Epidemiological, biological, and biochemical studies concur to support the beneficial role of chlorogenic acid in human health, along with other dietary phenolic compounds. Thus, chlorogenic acid has been reported to exert inhibitory effects on carcinogenesis in the large intestine, liver, and tongue, and a protective action on oxidative stress in vivo, together with anti-inflammatory, antidiabetic and antihypertensive activities. It is also claimed to have antifungal, antibacterial and antiviral effects with relatively low toxicity and side effects, alongside properties that do not lead to antimicrobial resistance. Due to its importance, numerous methods for determining chlorogenic acid (CGA), as well as for its derivatives from coffee beans and other plants, were elaborated. The most frequently used methods are infrared spectroscopy, high performance liquid chromatography (HPLC), capillary electrophoresis, liquid chromatography-mass spectrometry and chemiluminescence. Although these methods proved to be efficient for quantifying CGA and its derived products, a number of deficiencies were identified: they are time consuming, laborious, and require expensive instruments. Therefore, electrochemical methods have been developed and used in the determination of CGA in different nutraceuticals or food products. The present review aims to present the main progresses and performance characteristics of electrochemical sensors and biosensors used to detect CGA, as it is reported in a high number of relevant scientific papers published mainly in the last decade. Full article
(This article belongs to the Special Issue Sensor Chemical Reactions in Metal Oxide Nanocomposites)
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29 pages, 3060 KiB  
Review
Evaluation of Olive Oil Quality with Electrochemical Sensors and Biosensors: A Review
by Alexandra Virginia Bounegru and Constantin Apetrei
Int. J. Mol. Sci. 2021, 22(23), 12708; https://0-doi-org.brum.beds.ac.uk/10.3390/ijms222312708 - 24 Nov 2021
Cited by 7 | Viewed by 2854
Abstract
Electrochemical sensors, sensor arrays and biosensors, alongside chemometric instruments, have progressed remarkably of late, being used on a wide scale in the qualitative and quantitative evaluation of olive oil. Olive oil is a natural product of significant importance, since it is a rich [...] Read more.
Electrochemical sensors, sensor arrays and biosensors, alongside chemometric instruments, have progressed remarkably of late, being used on a wide scale in the qualitative and quantitative evaluation of olive oil. Olive oil is a natural product of significant importance, since it is a rich source of bioactive compounds with nutritional and therapeutic properties, and its quality is important both for consumers and for distributors. This review aims at analysing the progress reported in the literature regarding the use of devices based on electrochemical (bio)sensors to evaluate the bioactive compounds in olive oil. The main advantages and limitations of these approaches on construction technique, analysed compounds, calculus models, as well as results obtained, are discussed in view of estimation of future progress related to achieving a portable, practical and rapid miniature device for analysing the quality of virgin olive oil (VOO) at different stages in the manufacturing process. Full article
(This article belongs to the Special Issue Sensor Chemical Reactions in Metal Oxide Nanocomposites)
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30 pages, 4784 KiB  
Review
Analytical Methods Used in Determining Antioxidant Activity: A Review
by Irina Georgiana Munteanu and Constantin Apetrei
Int. J. Mol. Sci. 2021, 22(7), 3380; https://0-doi-org.brum.beds.ac.uk/10.3390/ijms22073380 - 25 Mar 2021
Cited by 560 | Viewed by 43424
Abstract
The study of antioxidants and their implications in various fields, from food engineering to medicine and pharmacy, is of major interest to the scientific community. The present paper is a critical presentation of the most important tests used to determine the antioxidant activity, [...] Read more.
The study of antioxidants and their implications in various fields, from food engineering to medicine and pharmacy, is of major interest to the scientific community. The present paper is a critical presentation of the most important tests used to determine the antioxidant activity, detection mechanism, applicability, advantages and disadvantages of these methods. Out of the tests based on the transfer of a hydrogen atom, the following were presented: the Oxygen Radical Absorption Capacity (ORAC) test, the Hydroxyl Radical Antioxidant Capacity (HORAC) test, the Total Peroxyl Radical Trapping Antioxidant Parameter (TRAP) test, and the Total Oxyradical Scavenging Capacity (TOSC) test. The tests based on the transfer of one electron include the Cupric Reducing Antioxidant Power (CUPRAC) test, the Ferric Reducing Antioxidant Power (FRAP) test, the Folin–Ciocalteu test. Mixed tests, including the transfer of both a hydrogen atom and an electron, include the 2,2′-Azinobis-(3-ethylbenzothiazoline-6-sulfonic acid (ABTS) test, and the [2,2-di(4-tert-octylphenyl)-1-picrylhydrazyl] (DPPH) test. All these assays are based on chemical reactions and assessing the kinetics or reaching the equilibrium state relies on spectrophotometry, presupposing the occurrence of characteristic colours or the discolouration of the solutions to be analysed, which are processes monitored by specific wavelength adsorption. These assays were successfully applied in antioxidant analysis or the determination of the antioxidant capacity of complex samples. As a complementary method in such studies, one may use methods based on electrochemical (bio)sensors, requiring stages of calibration and validation. The use of chemical methods together with electrochemical methods may result in clarification of the operating mechanisms and kinetics of the processes involving several antioxidants. Full article
(This article belongs to the Special Issue Sensor Chemical Reactions in Metal Oxide Nanocomposites)
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