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Topic Review
Separation and Recycling Potential of Rare Earth Elements
Rare earth elements (REEs) are key chemical raw materials in the development of low-carbon industrial processes and especially in green energy technologies. The REEs include 17 elements that can be found in nature (15 lanthanides La-Lu, Sc, and Y). They are ironically quite well represented in the Earth’s crust, except for the radioactive promethium, which is very rare. However, they are rarely found alone and at economically attractive concentrations, which make them expensive and complicated to extract and separate in high purity with conventional separation techniques. 
  • 1.3K
  • 10 Mar 2022
Topic Review
Catalytic Adsorptive Stripping Voltammetric Determination of Germanium
In organic free aqueous solutions, germanium is present in the form of Ge(OH)4 tetrahydroxide (pH < 7) or as H3GeO4−, which dominates in alkaline media (pH > 9). In the presence of many ligands containing carboxylic, di-orthophenolic, and polyalcoholic functional groups, Ge(IV) forms stable five-membered ring chelate complexes displaying coordination number 6.
  • 1.3K
  • 17 Feb 2022
Topic Review
Synthetic Hemorphin Analogs Containing Non-Natural Amino Acids
The endogenous hemorphins are bioactive peptides with activity on opioid receptors. Several research teams have synthesized, characterized, and pharmacologically evaluated synthetic hemorphin analogs containing unusual amino acids, D-amino acids, α-aminophosphonic acids, and their derivatives. Research focuses on the structure-activity relationship analysis, details on specific methods for their characterization, and the advantage of synthetic hemorphin analogs compared to endogenous peptides as potent biologically active compounds with a complex mechanism of action.
  • 1.3K
  • 05 Dec 2022
Topic Review
Electrochemical Determination of Kynurenine Pathway Metabolites
Kynurenine pathway (KP) is the major catabolic route of tryptophan, which generates an important enzyme cofactor (NAD+) and a variety of bioactive metabolites (so-called kynurenines) with immunosuppressive functions or neuroprotective, antioxidant, and toxic properties. It is involved in a variety of physiological processes, especially in conditions associated with immune dysfunction, central nervous system disorders, autoimmunity, infection, diabetes, and cancer. In normal conditions, tryptophan depletion via KP is initiated by the liver enzyme tryptophan 2,3-dioxygenase (TDO) and the extrahepatic enzyme - indoleamine 2,3-dioxygenase  (IDO) that contributes minimally to this process (5–10%). The extrahepatic KP becomes quantitatively more significant under conditions of immune activation. KP metabolites are frequently found in biofluids, tissues, and cell-delivered material at low nanomolar or low micromolar concentration levels. However, in disease conditions, abnormal tryptophan metabolism can be accompanied by changes in levels of KP metabolites.
  • 1.3K
  • 17 Nov 2021
Topic Review
Pharmaceutical and Microplastic Pollution in Water
Pharmaceuticals (PhACs) and microplastics (MPs) are emerging pollutants that pose serious environmental risks. PhACs have been found in low concentrations in a variety of environmental samples, including sewage treatment plant effluents, surface water, seawater, and groundwater, in a number of countries.
  • 1.3K
  • 27 Oct 2022
Topic Review
Solubility of Organic Compounds in Subcritical Water
Data on the solubility and decomposition of organic compounds in subcritical water, a green solvent, are needed in environmental remediation, chemistry, chemical engineering, medicine, polymer, food, agriculture, and many other fields. The solubility of organics is significantly enhanced with increasing water temperature. Likewise, the percentage of organic decomposition also increases with higher temperature.
  • 1.3K
  • 09 Mar 2023
Topic Review
Flavonoid Profile in Some Plants of Annona Genus
The Annonaceae family is widely distributed in subtropical and tropical regions. Several species of this family are known for their pharmacological and beneficial properties to human health, mainly attributed to flavonoids.
  • 1.3K
  • 12 Jun 2023
Topic Review
Metal Oxide-Based Photocatalysts for CO2 Reduction
The photoconversion of CO2 into solar fuels seems to curb greenhouse effect and resolve the energy crisis. One of the challenges in developing practical CO2 photoconversion catalysts is to design materials with a low cost, high activity and good stability. The excellent photocatalysts based on TiO2, WO3, ZnO, Cu2O and CeO2 metal oxides that are cost-effective and long-lasting were discussed. Strategies to improve CO2 photoconversion efficiency are summarized and photocatalysts forms of 0D, 1D, 2D and 3DOM (zero/one/two-dimensional and three-dimensional-ordered macroporous, respectively) are involved, which can inspire the future improvement in photochemistry.
  • 1.3K
  • 21 Mar 2023
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. 
  • 1.3K
  • 10 Jul 2023
Topic Review
Fluorescent Chemosensors Based on Polyamine Ligands
Polyamine ligands are water-soluble receptors that are able to coordinate, depending on their protonation degree, either metal ions, anionic, or neutral species. Furthermore, the presence of fluorescent signaling units allows an immediate visual response/signal. For these reasons, they can find applications in a wide variety of fields, mainly those where aqueous media is necessary, such as biological studies, wastewater analysis, soil contamination, etc.
  • 1.3K
  • 29 Dec 2021
Topic Review
Acetylation (or in IUPAC nomenclature ethanoylation)
Acetylation (or in IUPAC nomenclature ethanoylation) describes a reaction that introduces an acetyl functional group into a chemical compound. Deacetylation is the removal of an acetyl group. Acetylation refers to the process of introducing an acetyl group (resulting in an acetoxy group) into a compound, namely the substitution of an acetyl group for an active hydrogen atom. A reaction involving the replacement of the hydrogen atom of a hydroxyl group with an acetyl group (CH3CO) yields a specific ester, the acetate. Acetic anhydride is commonly used as an acetylating agent reacting with free hydroxyl groups. For example, it is used in the synthesis of aspirin, heroin, and THC-O-acetate.
  • 1.3K
  • 17 Nov 2022
Topic Review
Vertical Graphene
Vertical Graphene is obtained using the plasma-enhanced chemical vapor deposition (PECVD) method, and different VG types with other properties can be obtained by changing the process parameters. VG is part of the graphene family; properties such as excellent electrical conductivity, thermal conductivity, chemical stability, and a large, specific surface area make it suitable for biomedical applications. Examples of biomedical applications in which VG is used are biosensors, electrochemical sensors, modified surfaces for bone growth, regeneration, and for antimicrobial effects.
  • 1.3K
  • 04 May 2023
Topic Review
Meta-Analysis and Analytical Methods in Cosmetics Formulation
The ever-evolving cosmetic industry requires advanced analytical techniques to explore, understand, and optimize product performance at nano, micro, and macroscopic levels. Nowadays, these insights are crucial for translating microstructure behavior into macroscopic properties. This knowledge is essential to formulate products with a lower carbon footprint and a higher sustainability profile, incorporating, at the same time, natural or biobased raw materials.
  • 1.3K
  • 22 Feb 2024
Topic Review
Inorganic Pyrophosphatase Activities Non-Radioactive Assays
Inorganic pyrophosphatase (PPase) is a ubiquitous enzyme that converts pyrophosphate (PPi) to phosphate and, in this way, controls numerous biosynthetic reactions that produce PPi as a byproduct. PPase activity is generally assayed by measuring the product of the hydrolysis reaction, phosphate. This reaction is reversible, allowing PPi synthesis measurements and making PPase an excellent model enzyme for the study of phosphoanhydride bond formation. 
  • 1.3K
  • 30 Apr 2021
Topic Review
Electrochemical Biosensing of SARS-CoV-2 Virus for COVID-19 Management
Rapid and early diagnosis of lethal coronavirus disease-19 (COVID-19) caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is an important issue considering global human health, economy, education, and other activities. The advancement of understanding of the chemistry/biochemistry and the structure of the SARS-CoV-2 virus has led to the development of low-cost, efficient, and reliable methods for COVID-19 diagnosis over “gold standard” real-time reverse transcription-polymerase chain reaction (RT-PCR) due to its several limitations. This led to the development of electrochemical sensors/biosensors for rapid, fast, and low-cost detection of the SARS-CoV-2 virus from the patient’s biological fluids by detecting the components of the virus, including structural proteins (antigens), nucleic acid, and antibodies created after COVID-19 infection. 
  • 1.2K
  • 08 Aug 2022
Topic Review
Biosensor Technology for Insulin Detection
Biosensor technology is a multidisciplinary field where biology, engineering and nanotechnology promise solutions for healthcare challenges enabling personalised medicine for disease prognosis, diagnosis and drug delivery. The ability to use a point-of-care sensor to measure insulin concurrently with glucose would allow for a much better assessment of endogenous insulin activity, enabling real-time adjustments in insulin dosing to be made while minimising the likelihood of occurrence of extremes of hypoglycaemia or hyperglycaemia.
  • 1.2K
  • 17 Jul 2023
Topic Review
Sensors for Contaminants Detection in Hydrogen Fuel
Sensors can be used to prevent hydrogen from reaching flammable levels by triggering alarms and activating ventilation or shutdown of systems. Therefore, hydrogen sensors are an important enabling technology for the safe use of hydrogen. Sensors could even have other applications, such as contributing to ensure the lifetime of fuel cell electrical vehicles by warning if the hydrogen quality is not adequate. Here, chemical sensors that respond to a particular analyte in a selective and reversible way can be used in order to indicate the presence of impurities that may be harmful to the Fuel Cell Electrical Vehicle (FCEV). 
  • 1.2K
  • 19 Apr 2022
Topic Review
Separation and Analytical Techniques Used in Snake Venomics
The deleterious consequences of snake envenomation are due to the extreme protein complexity of snake venoms. Therefore, the identification of their components is crucial for understanding the clinical manifestations of envenomation pathophysiology and for the development of effective antivenoms. In addition, snake venoms are considered as libraries of bioactive molecules that can be used to develop innovative drugs. Numerous separation and analytical techniques are combined to study snake venom composition including chromatographic and electrophoretic techniques.
  • 1.2K
  • 28 Jul 2022
Topic Review
Intelligent Sensor arrays for Early Detection of Diabetes
At present, it is unquestionable that machine learning (ML) modeling is one of the most promising and powerful tools for the development of diagnosis methods and technologies. It permits the fast cribbage and analysis of huge amounts of data from overwhelmingly complex biological matrices which, applied to diagnostics, can be translated into valuable support technologies that would ease rapid decision-making in early diagnosis and screening programs. It has been seen that one can find a great number of colorimetric and electrochemical sensing methods for the detection of biomarkers related to diabetes mellitus (DM) and diabetic rethinopathy (DR), including some recent efforts towards the development of sensor-array technologies exploiting or not ML models for the sensing of diverse biomarkers and for diagnose purposes (including DM). 
  • 1.2K
  • 14 Mar 2022
Topic Review
Liquid-Chromatographic Methods for Carboxylic Acids
Carboxyl-bearing low-molecular-weight compounds such as keto acids, fatty acids, and other organic acids are involved in a myriad of metabolic pathways owing to their high polarity and solubility in biological fluids. Various disease areas such as cancer, myeloid leukemia, heart disease, liver disease, and lifestyle diseases (obesity and diabetes) were found to be related to certain metabolic pathways and changes in the concentrations of the compounds involved in those pathways. Therefore, the quantification of such compounds provides useful information pertaining to diagnosis, pathological conditions, and disease mechanisms, spurring the development of numerous analytical methods for this purpose.
  • 1.2K
  • 05 Feb 2021
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