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Topic Review
HR-MAS NMR in Plant Metabolomics
Metabolomics is used to reduce the complexity of plants and to understand the underlying pathways of the plant phenotype. The metabolic profile of plants can be obtained by mass spectrometry or liquid-state NMR. Extraction of metabolites from the sample is necessary for both techniques to obtain the metabolic profile. This extraction step can be eliminated by making use of high-resolution magic angle spinning (HR-MAS) NMR which allows to get metabolic profile directly in intact plant tissues such as intact leaves. An HR-MAS NMR-based metabolomics workflow is thus established that provide a novel platform for obtaining important information of regular metabolic network non-invasively.
  • 1.5K
  • 14 Jul 2021
Biography
Victoria Samanidou
Dr Victoria Samanidou is Full Professor and Director of the Laboratory of Analytical Chemistry in the Department of Chemistry of Aristotle University of Thessaloniki, Greece. Her research interests focus on the development of sample preparation methods using sorptive extraction prior to chromatographic analysis. She has co-authored 202 original research articles in peer reviewed journals and
  • 1.5K
  • 19 Aug 2022
Topic Review
Grapevine Cane Extracts
Grapevine canes are viticulture waste that is usually discarded without any further use. However, recent studies have shown that they contain significant concentrations of healthpromoting compounds, such as stilbenes, secondary metabolites of plants produced as a response to biotic and abiotic stress from fungal disease or dryness. Stilbenes have been associated with antioxidant, anti‐inflammatory, and anti‐microbial properties and they have been tested as potential treatments of cardiovascular and neurological diseases, and even cancer, with promising results. Stilbenes have been described in the different genus of the Vitaceae family, the Vitis genera being one of the most widely studied due to its important applications and economic impact around the world. This entry presents an in‐depth study of the composition and concentration of stilbenes in grapevine canes. The results show that the concentration of stilbenes in grapevine canes is highly influenced by the Vitis genus and cultivar aspects (growing conditions, ultraviolet radiation, fungal attack, etc.). Different methods for extracting stilbenes from grapevine canes have been reviewed, and the extraction conditions have also been studied, underlining the advantages and disadvantages of each technique. After the stilbenes were extracted, they were analyzed to determine the stilbene composition and concentration. Analytical techniques have been employed with this aim, in most cases using liquid chromatography, coupled with others such as mass spectrometry and/or nuclear magnetic resonance to achieve the individual quantification. Finally, stilbene extracts may be applied in multiple fields based on their properties. The five most relevant are preservative, antifungal, insecticide, and biostimulant applications. The current state‐of‐the‐art of the above applications and their prospects are discussed.
  • 1.5K
  • 11 Sep 2020
Topic Review
Electrochemical Biosensing of Dopamine Neurotransmitter
Neurotransmitters are biochemical molecules that transmit a signal from a neuron across the synapse to a target cell, thus being essential to the function of the central and peripheral nervous system. Dopamine is one of the most important catecholamine neurotransmitters since it is involved in many functions of the human central nervous system, including motor control, reward, or reinforcement. It is of utmost importance to quantify the amount of dopamine since abnormal levels can cause a variety of medical and behavioral problems. 
  • 1.5K
  • 17 Jun 2021
Topic Review
Capacitive Field-Effect Bio-Chemical Sensors
       Electrolyte-insulator-semiconductor (EIS) field-effect sensors belong to a new generation of electronic chips for biochemical sensing, enabling a direct electronic readout. The review gives an overview on recent advances and current trends in the research and development of chemical sensors and biosensors based on the capacitive field-effect EIS structure—the simplest field-effect device, which represents a biochemically sensitive capacitor. Fundamental concepts, physicochemical phenomena underlying the transduction mechanism and application of capacitive EIS sensors for the detection of pH, ion concentrations, and enzymatic reactions, as well as the label-free detection of charged molecules (nucleic acids, proteins, and polyelectrolytes) and nanoparticles, are presented and discussed.
  • 1.5K
  • 19 Apr 2022
Topic Review
Contaminant Cocktails of High Concern in Honey
Environmental pollution is a crucial problem in our society, having a better understanding of its consequences, which include the increase of contaminant cocktails present in the environment. The contamination of honeybees can occur through their interaction with the nearby environment. Therefore, if honeybees are previously contaminated, there is a possibility of contamination of their products, such as honey as natural, or minimally processed, product, resulting from the honeybees’ activity.
  • 1.5K
  • 14 Apr 2023
Topic Review
Glass Fiber Coated Sol–Gel Poly-Diphenylsiloxane
A novel simple and sensitive, time-based flow injection solid phase extraction system was developed for the automated determination of metals at low concentration. The potential of the proposed scheme, coupled with flame atomic absorption spectrometry (FAAS), was demonstrated for trace lead and chromium(VI) determination in environmental water samples. The new sorptive extraction system, consisted of an online microcolumn packed with glass fiber coated with sol–gel poly (diphenylsiloxane) (sol–gel PDPS), which is presented here for the first time.
  • 1.5K
  • 13 Jan 2021
Topic Review
Surface Modification in Surface Plasmon Resonance Assays
Surface plasmon resonance (SPR) comprises several surface-sensitive techniques that enable the trace and ultra-trace detection of various analytes through affinity pairing. 
  • 1.5K
  • 27 Apr 2023
Topic Review
Chromatography in Ukraine
The development of chromatographic science in Ukraine is due to the widespread use of chromatography to solve practical problems. The centers of chromatographic research in Ukraine are in large cities: Kyiv, Kharkiv, Lviv, Odessa, and others. Along with the development of chromatographic research methods, analysis methods for control of food and agricultural raw materials, medicinal products, petroleum products, and determination of the environmental pollution state are created. Chromatography is used in medicine, pharmacology, biology, and other sciences.
  • 1.4K
  • 14 Jun 2022
Topic Review
Trending Methods for Rapid Cannabinoids Detection
Roadside testing of illicit drugs such as tetrahydrocannabinol (THC) requires simple, rapid, and cost-effective methods. The need for non-invasive detection tools has led to the development of selective and sensitive platforms, able to detect phyto- and synthetic cannabinoids by means of their main metabolites in breath, saliva, and urine samples. One may estimate the time passed from drug exposure and the frequency of use by corroborating the detection results with pharmacokinetic data. Modified surfaces can also act as filters that allow only the target analyte to participate in the electrode reaction. In the case of cannabinoids, as in the case of other drugs, the investigation of the mechanism of action within the organism is the basis of biosensor development.
  • 1.4K
  • 18 Nov 2022
Topic Review
Origanum majorana Essential Oil—Chemistry and Pesticide Activity
Origanum majorana is a medicinal and aromatic plant that belongs to the Lamiaceae family. It is cultivated in several parts of the world and, due to its splendid aroma and taste, is widely used for culinary purposes and in perfumes. The essential oil of the plant, to which is attributed its aroma, contains many secondary metabolites with valuable biological activity. One of them is the pesticide activity, which has attracted much interest. Given the necessity of replacing synthetic pesticides, essential oils are studied in an attempt to find naturally derived products.
  • 1.4K
  • 09 Dec 2022
Topic Review
Liquid Chromatography Separation Mechanism
Separation is a critical process to isolate a particular compound, whether it is a natural product or a synthetic product. Studies of a compound’s characteristics and elucidation structure provides reliable results for pure compounds because there is no interference from other compounds. The primary source of difficulty in a separation process is the high similarity between two or more compounds, such as racemic and homologous mixtures. Liquid chromatography has proven to be an effective solution to those problems. The key to liquid chromatography separation is a sustainable retention and elution process. Stationary phases are essential for separating compounds in liquid chromatography. Various liquid chromatography columns of both preparative and quantitative types have been used and continue to develop. This research will discuss the separation mechanism in liquid chromatography.
  • 1.4K
  • 02 Mar 2022
Topic Review
Amorphized Cellulose
Amorphized cellulose is partially or completely decrystallized cellulose. Natural celluloses isolated from terrestrial plants (e.g. cotton, wood, etc.), algae (e.g. Cladophora sp., Valonia ventricosa, etc.), shells of some marine tunicates (e.g. Ascidia sp., Halocynthia roretzi, etc.), and synthesized by some bacteria (e.g. Glucon­aceto­bacter sp., Medusomyces gisevii, etc.) along with microcrystalline cellulose, are semicrystalline biopolymers with a crystallinity degree of 50 to 80%.
  • 1.4K
  • 23 Dec 2021
Topic Review
Green Extraction Techniques Applications in Different Fields
Green extraction techniques (GreETs) emerged in the last decade as greener and sustainable alternatives to classical sample preparation procedures aiming to improve the selectivity and sensitivity of analytical methods, simultaneously reducing the deleterious side effects of classical extraction techniques (CETs) for both the operator and the environment. The implementation of improved processes that overcome the main constraints of classical methods in terms of efficiency and ability to minimize or eliminate the use and generation of harmful substances will promote more efficient use of energy and resources in close association with the principles supporting the concept of green chemistry.
  • 1.4K
  • 10 May 2022
Topic Review
Chemical Derivatization in Flow Analysis
Chemical derivatization involves modification of the analyte for improving selectivity and/or sensitivity. It is particularly attractive in flow analysis in view of its highly reproducible reagent addition(s) and controlled timing. Then, measurements without attaining the steady state, kinetic discrimination, exploitation of unstable reagents and/or products, as well as strategies compliant with Green Analytical Chemistry, have been efficiently exploited. Flow-based chemical derivatization has been accomplished by different approaches, involving e.g. flow and manifold programming, solid-phase reagents, and strategies for sample insertion and reagent addition, as well as to increase sample residence time.
  • 1.4K
  • 08 Mar 2022
Topic Review
Electric Field Catalytic Reactions
The role of catalysis in controlling chemical reactions is crucial. As an important external stimulus regulatory tool, electric field (EF) catalysis enables further possibilities for chemical reaction regulation. The regulation mechanism of electric fields and electrons on chemical reactions has been modeled. The electric field at the single-molecule electronic scale provides a powerful theoretical weapon to explore the dynamics of individual chemical reactions. The combination of electric fields and single-molecule electronic techniques not only uncovers new principles but also results in the regulation of chemical reactions at the single-molecule scale. 
  • 1.4K
  • 10 Jul 2023
Topic Review Peer Reviewed
Catalytic Membrane Ozonation
Catalytic membrane ozonation is a hybrid process that combines membrane filtration and catalytic ozonation. The membrane deposited with an appropriate solid material acts as catalyst. As a consequence, the catalytic membrane contactor can act simultaneously as contactor (i.e., improving the transfer/dissolution of gaseous ozone into the liquid phase), as well as reactor (i.e., oxidizing the organic compounds). It can be used in water and wastewater treatment limiting the disadvantages of membrane filtration (i.e., lower removal rates of emerging contaminants or fouling occurrence) and ozonation (i.e., selective oxidation, low mineralization rates, or bromate (BrO3−) formation). The catalytic membrane ozonation process can enhance the removal of micropollutants and bacteria, inhibit or decrease the BrO3− formation and additionally, restrict the membrane fouling (i.e., the major/common problem of membranes’ use). Nevertheless, the higher operational cost is the main drawback of these processes. 
  • 1.4K
  • 13 Apr 2022
Topic Review
Aurones
Aurones are part of the wide family of polyphenols. More specifically, they may be acknowledged as the lower structural counterparts of the best-known flavones, a subclass of flavonoids.
  • 1.4K
  • 27 Jan 2022
Topic Review
Analysis Methodology of Precursors to 3-Sulfanylhexan-1-ol in Wine
Volatile polyfunctional thiol compounds, particularly 3-sulfanylhexan-1-ol (3SH) and 3-sulfanylhexyl acetate (3SHA), are key odorants contributing to the aroma profile of many wine styles, generally imparting tropical grapefruit and passionfruit aromas. 3SH and 3SHA are present in negligible concentrations in the grape berry, juice, and must, suggesting that they are released from non-volatile precursors present in the grape. The exploration of the nature and biogenesis of these precursors to 3SH and 3SHA has proven important for the elucidation of polyfunctional thiol biogenesis during alcoholic fermentation.
  • 1.3K
  • 27 Jul 2022
Topic Review
Effervescence-Assisted Microextraction
Effervescence-assisted microextraction emerged in 2011 as a new alternative in this context. The technique uses in situ-generated carbon dioxide as the disperser, and it has been successfully applied in the solid-phase and liquid-phase microextraction fields. This minireview explains the main fundamentals of the technique, its potential and the main developments reported.
  • 1.3K
  • 14 Jan 2021
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