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Topic Review
Activation of Biosynthetic Gene Clusters in Fungi
In the early 2000s, technological advances in genome sequencing and bioinformatics on filamentous fungi began to reveal a discrepancy between the number of biosynthetic gene clusters (BGCs) encoding the biosynthesis of fungal secondary metabolites and the actual number of identified fungal compounds from the target strain. The discovery of cryptic BGCs in microorganisms, including fungi, has spurred the development of new experimental methodologies for identifying the secondary metabolites of these clusters, which led to the realization that they have the potential to produce novel specialized metabolites, giving rise to a new field of research called genome-guided natural product discovery.
  • 379
  • 01 Jun 2023
Topic Review
Metal Hydrides and Graphene Supports
Energy production, distribution, and storage remain paramount to a variety of applications that reflect on our daily lives, from renewable energy systems, to electric vehicles and consumer electronics. Hydrogen is the sole element promising high energy, emission-free, and sustainable energy, and metal hydrides in particular have been investigated as promising materials for this purpose. While offering the highest gravimetric and volumetric hydrogen storage capacity of all known materials, metal hydrides are plagued by some serious deficiencies, such as poor kinetics, high activation energies that lead to high operating temperatures, poor recyclability, and/or stability, while environmental considerations related to the treatment of end-of-life fuel disposal are also of concern. Graphene is a 2D material with very appealing properties, highlighting its potential use as support for various reactive species, including metals and metal hydrides. By embedding hydride species into graphene supports, valuable nanocomposites can be obtained with direct use for energy storage applications.
  • 629
  • 01 Jun 2023
Topic Review
Tropylium Ion
The tropylium ion is a non-benzenoid aromatic species that works as a catalyst. This chemical entity brings about a large number of organic transformations, such as hydroboration reactions, ring contraction, the trapping of enolates, oxidative functionalization, metathesis, insertion, acetalization, and trans-acetalization reactions. The tropylium ion also functions as a coupling reagent in synthetic reactions. This cation’s versatility can be seen in its role in the synthesis of macrocyclic compounds and cage structures.
  • 1.8K
  • 01 Jun 2023
Topic Review
Principles of pH-Responsive Drug Delivery
The paradigm of drug carriers’ usage to overcome the non-specific distribution of therapeutic agents in the body, including chemotherapeutic substances that exert severe toxic stress on healthy tissues, has been actively developed. One of the main pillars of this paradigm is the increased or even selective accumulation of drug delivery systems (DDSs) carrying therapeutic agents in tumor interstitium harnessing the differences between normal and cancer tissues properties. Thus, structural features of tumors, such as hypervascularization, vascular pathologies, and impaired functionality of lymphatic drainage, can be utilized to differentiate tumors from healthy tissues and selectively accumulate drug carriers. In particular, tumor-surrounding vessels are characterized by defects in the endothelial layer lining the blood vessel wall, represented by wide fenestrations (up to several microns) and other features that lead to an increase in the permeability of this barrier for small objects, making the effective extravasation of nanosized carriers from the bloodstream to tumor interstitium possible. Methods of selective therapy via the systemic administration of therapeutic agents based on increased permeability of the tumor vessels’ wall, known under the general name of the EPR effect, have become widespread and have inspired the creation of a large number of vehicles proposed for the delivery of chemotherapeutic agents. In summary, the EPR effect implies the extravasation of nanosized drug carriers through endothelial fenestra and their retention in the interstitial volume of the tumor due to dysfunctional lymphatic drainage.
  • 467
  • 01 Jun 2023
Biography
Jesus Vicente de Julián-Ortiz
Bachelor of Chemical Sciences in the specialty of Biochemistry. He did the doctorate program in Organic Synthesis and Fine Chemistry. Doctor of Pharmacy. His initial research focused on the design, synthesis and microbiological tests of new potential drugs against Herpes simplex virus type 1, as well as the design of new potential antimycobacterial agents, including the corresponding activity
  • 460
  • 01 Jun 2023
Topic Review
Supercapacitors with Triboelectric Nanogenerators
The ever-growing interest in wearable electronic devices has unleashed a strong demand for sustainable and flexible power sources that are represented by the combination of flexible energy harvesting with storage devices/technologies. Triboelectric nanogenerators (TENG), which harvest mechanical energy and charge their matching supercapacitors (SCs), may form a distributed power system with flexibility to tap their potential applications in powering wearable electronic devices.
  • 433
  • 31 May 2023
Topic Review
Chemical Composition on Heating Value of Biomass
Biomass has become an increasingly important resource for energy generation. It is well known that the heating value of lignin is significantly higher (23.26–25.58 MJ/kg) than that of polysaccharides (18.6 MJ/kg), while extractives often have higher heating values (HHVs) over 30 MJ/kg, depending on their oxidation levels. Therefore, the proportions of the chemical components in biomass determine its HHV.
  • 1.2K
  • 31 May 2023
Topic Review
Semiconductor Metal Oxide Sensors in Reducing Gases Detection
The sensitivity of semiconductor metal oxide sensors can be significantly increased by using nanostructured sensitive layers based on two-component materials, consisting of metal oxides with different electronic characteristics and chemical properties.
  • 682
  • 31 May 2023
Topic Review
Applications of Carbon Nanodots
Carbon dots have drawn immense attention and prompted intense investigation. The latest form of nanocarbon, the carbon nanodot, is attracting intensive research efforts, similar to its earlier analogues, namely, fullerene, carbon nanotube, and graphene. One outstanding feature that distinguishes carbon nanodots from other known forms of carbon materials is its water solubility owing to extensive surface functionalization (the presence of polar surface functional groups). These carbonaceous quantum dots, or carbon nanodots, have several advantages over traditional semiconductor-based quantum dots. They possess outstanding photoluminescence, fluorescence, biocompatibility, biosensing and bioimaging, photostability, feedstock sustainability, extensive surface functionalization and bio-conjugation, excellent colloidal stability, eco-friendly synthesis (from organic matter such as glucose, coffee, tea, and grass to biomass waste-derived sources), low toxicity, and cost-effectiveness.
  • 432
  • 30 May 2023
Topic Review
Corey-Seebach Reagent in the 21st Century
The Corey-Seebach reagent plays an important role in organic synthesis because of its broad synthetic applications. The Corey-Seebach reagent is formed by the reaction of an aldehyde or a ketone with 1,3-propane-dithiol under acidic conditions, followed by deprotonation with n-butyllithium. A large variety of natural products (alkaloids, terpenoids, and polyketides) can be accessed successfully by utilizing this reagent.
  • 577
  • 30 May 2023
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