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Topic Review
AIE Material Design Strategy Based on Functional Groups
The common fluorescent conjugated materials present weak or quenching luminescent phenomena in the solid or aggregate state (ACQ), which limits their applications in medicine and biology. Certain materials, named aggregation-induced emission (AIE) fluorescent materials, have exhibited strong luminescent properties in the aggregate state, which can overcome the ACQ phenomenon. Due to their intrinsic properties, the AIE materials have been successfully used in biolabeling, where they can not only detect the species of ions and their concentrations in organisms, but can also monitor the organisms’ physiological activity. In addition, these kinds of materials often present non-biological toxicity. Thus, AIE materials have become some of the most popular biofluorescent probe materials and are attracting more and more attention. 
  • 399
  • 08 Feb 2023
Topic Review
Ammonium Nitrate Disasters
When heated, ammonium nitrate decomposes non-explosively into gases including oxygen; however, it can be induced to decompose explosively by detonation. Large stockpiles of the material can be a major fire risk due to their supporting oxidation, and may also detonate, as happened in the Texas City disaster of 1947, which led to major changes in the regulations for storage and handling. There are two major classes of incidents resulting in explosions: In the first case, the explosion happens by the mechanism of shock to detonation transition. The initiation happens by an explosive charge going off in the mass, by the detonation of a shell thrown into the mass, or by detonation of an explosive mixture in contact with the mass. The examples are Kriewald, Morgan, Oppau, Tessenderlo, and Traskwood. In the second case, the explosion results from a fire that spreads into the ammonium nitrate (AN) itself (Texas City, Brest, Tianjin), or to a mixture of an ammonium nitrate with a combustible material during the fire. The fire must be confined at least to a degree for successful transition from a fire to an explosion (a phenomenon known as "deflagration to detonation transition", or DDT). Pure, compact AN is stable and very difficult to initiate. However, there are numerous cases when even impure AN did not explode in a fire. Ammonium nitrate decomposes in temperatures above 210 °C (410 °F). Pure AN is stable and will stop decomposing once the heat source is removed, but when catalysts are present, the reaction can become self-sustaining (known as self-sustaining decomposition, or SSD). This is a well-known hazard with some types of NPK fertilizers and is responsible for the loss of several cargo ships.
  • 487
  • 28 Oct 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%.
  • 600
  • 23 Dec 2021
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.
  • 587
  • 27 Jul 2022
Topic Review
Analysis of Phytic Acid
Phytate is a six-fold dihydrogenphosphate ester of myo‑inositol or cis-1,2,3,5-trans-4,6-cyclohexanehexol which is the most abundant of nine possible isomers of inositol (Ins). Myo-orientation is also found in the case of phytic acid, which is due to the fact that the maximal number (i.e., five out of six) of phosphate groups are present in thermodynamically stabilized equatorial position. However, the molecule can be inverted from equatorial (1a5e) to the axial (5a1e) orientation between pH 9.0 and pH 9.5.
  • 1.7K
  • 18 Jan 2021
Topic Review
Analytical Methods for Codeine Determination
Codeine is derived from morphine, an opioid analgesic, and has weaker analgesic and sedative effects than the parent molecule. This weak opioid is commonly used in combination with other drugs for over-the-counter cough relief medication. Due to the psychoactive properties of opioid drugs, the easily obtained codeine often becomes subject to misuse. Codeine misuse has emerged as a concerning public health issue due to its associated adverse effects such as headache, nausea, vomiting, and hemorrhage. Thus, it is very important to develop reliable analytical techniques to detect codeine for both quality control of pharmaceutical formulations and identifying drug misuse in the community. This review aims to provide critical outlooks on analytical methods napplicable to the determination of codeine.
  • 1.0K
  • 11 Mar 2021
Topic Review
Analytical Methods for Detection and Quantification of Neurotransmitters
Recognized for its speed and selectivity, high-precision liquid chromatography with an electrochemical detector (HPLC-ECD) enables direct analysis of intracerebral microdialysis samples without complex derivatization. Various chromatographic methods, including reverse phase (RP), are explored for neurotransmitters (NTs) and metabolites separation. 
  • 99
  • 25 Jan 2024
Topic Review
Analytical Techniques for Detection and Quantification of PFAS
The established methods for performing poly-fluoroalkyl substances (PFAS) analysis are based on Liquid Chromatography-Mass Spectrometry (LC-MS). Both the sample preparation and the development of the chromatographic set-up are crucial steps for reliable, precise, and accurate measurements. According to the literature, the conventional reverse phase separation stationary phase column is the most widely utilized approach. To improve the chromatographic performance, columns equipped with polar functionalized C18 alkyl chains were introduced.
  • 395
  • 21 Jun 2023
Topic Review
Anti-Aggregation-Enabled Colorimetric Sensing Applications of Nanoparticles
Gold- and silver nanoparticles (Au NPs and Ag NPs)-based colorimetric detection of specific analytes has attracted intense research interest and is still in great demand. The majority of Au NPs- and Ag NPs-based sensory reports have revealed that, during the analyte recognition, dispersed NPs typically aggregated and displayed color changes from wine-red to blue/purple and yellow to orange/brown, respectively. On the other hand, only a few reports demonstrated that the aggregated Au NPs and Ag NPs underwent anti-aggregation in the presence of certain analytes, which displayed reversed color changes from blue/purple to wine-red and orange/brown to yellow, correspondingly. There are some examples of anti-aggregation phenomena mentioned in a vast number of studies on Au NPs- and Ag NPs-based colorimetric sensors via NP aggregation.
  • 388
  • 29 Dec 2022
Topic Review
Antibiotics Extraction from Shrimps Prior to Chromatographic Analysis
Antibiotics are used in aquaculture in order to control the infection outbreaks. They are natural, semisynthetic or synthetic compounds and their antibacterial effect resides on their ability to eliminate the bacteria or hinder their growth. The widespread use of antibiotics in veterinary practice and aquaculture has led to the increase of antimicrobial resistance in food-borne pathogens that may be transferred to humans. 
  • 288
  • 18 Jul 2023
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