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Topic Review
Ascorbic Acid-Induced Reactions
Ascorbic acid is the most well-known vitamin found in different types of food. It has tremendous medical applications in several different fields such as in pharmaceuticals, cosmetics, and in organic synthesis. Ascorbic acid can be used as a substrate or mediator in organic synthesis. In this review, we report ascorbic acid-catalyzed reactions in organic synthesis. Several examples are included in this review to demonstrate that ascorbic acid is a versatile catalyst for the synthesis of diverse organic compounds. Reactions catalyzed by ascorbic acid are performed in organic or aqueous media. The readily available and easy handling features of ascorbic acid make these procedures highly fascinating.
  • 2.9K
  • 25 Nov 2020
Topic Review
Fluorescein Derivatives
This entry is dealing with fluorescein and its derivatives and focuses on their uses as pH-sensor in a biological context. It gathers chemical properties of the fluorescein family of compounds combined to biological issues. 
  • 2.8K
  • 17 Dec 2020
Topic Review
Charlotte's Web (Cannabis)
Charlotte's Web is a high-cannabidiol (CBD), low-tetrahydrocannabinol (THC) Cannabis strain marketed as a dietary supplement under federal law of the United States. It is produced by the Stanley brothers in Colorado. It does not induce the psychoactive "high" typically associated with recreational marijuana strains that are high in THC. In September 2014, the Stanleys announced that they would ensure that the product consistently contained less than 0.3% THC. Charlotte's Web is named after Charlotte Figi, born (2006-10-18) October 18, 2006 (age 16), whose story has led to her being described as "the girl who is changing medical marijuana laws across America." Her parents and physicians say she experienced a reduction of her epileptic seizures brought on by Dravet syndrome after her first dose of medical marijuana at five years of age. Her usage of Charlotte's Web was first featured in the 2013 CNN documentary "Weed". Media coverage increased demand for Charlotte's Web and similar products high in CBD, which has been used to treat epilepsy in toddlers and children. It was originally called "Hippie's Disappointment" as it was a strain that had high CBD and could not induce a "high". While anecdotal reports have sparked interest in treatment with cannabinoids, there is not enough evidence to draw conclusions with certainty about their safety or efficacy. Physicians worry that some parents are willing to try treatments before proper research has been conducted, and that they may be disappointed. They are "alarmed by parallels to past miracle-cure manias later proved false..." and "...wary of the heightened placebo effect in treatments involving children, when reports of progress depend on the view of parents."
  • 2.8K
  • 02 Nov 2022
Topic Review
Fucoxanthin Extracted from Brown Algae
The scientific community has corroborated the numerous beneficial activities of fucoxanthin, such as its antioxidant, anti-inflammatory, anticancer or neuroprotective effects, among others. These properties have attracted the attention of nutraceutical, cosmetic and pharmacological industries, giving rise to various possible applications. Fucoxanthin may be chemically produced, but the extraction from natural sources is considered more cost-effective, efficient and eco-friendly. Thus, identifying suitable sources of this compound and giving a general overview of efficient extraction, quantification, purification and stabilization studies is of great importance for the future production and commercialization of fucoxanthin. The entry describes the potential applications of fucoxanthin pigment. Its production must face several challenges since its chemical synthesis represents a complex process which is not efficient and the extraction method from marine organisms has been not standardized. The main characteristic of a profitable product is to be obtained by using simple, fast, and based on low-cost technologies. This work provides an overview of different extraction conditions that may help in the standardization of the process, especially important at an industrial level. Therefore, the main aim of this work has been to underline the best algae species in terms of fucoxanthin production and the most promising extraction and purification methods, while offering a complete panorama of the described bioactivities of fucoxanthin which includes bioavailability, administration via, doses and stability of the molecule under different conditions.
  • 2.8K
  • 06 Feb 2021
Topic Review
Homogeneous and Heterogeneous Copper Catalyst
The applications of Copper-based nanoparticles have received great attention due to the earth-abundant, low toxicity and inexpensive. Due to these characteristics, copper nanoparticles have generated a great deal of interest especially in the field of catalysis. Traditional Ullmann-type couplings suffer from limited substrate scopes and harsh reaction conditions. The introduction of a new copper-based catalyst over the past two decades has totally changed this situation as it enables the reaction promoted in mild condition. The reaction scope has also been greatly expanded, rendering this copper-based cross-coupling attractive for both academia and industry. Transition metal-catalyzed chemical transformation of organic electrophiles and organometallic reagents belong to the most important cross-coupling reaction in organic synthesis. The biaryl ether division is not only popular in natural products and synthetic pharmaceuticals but also widely found in many pesticides, polymers, and ligands. Copper catalyst has received great attention owing to the low toxicity and low cost. The introduction of homogeneous copper catalysts with the presence of bidentate ligands and also heterogeneous copper catalyst over the past two decades has totally changed this situation as these ligands enable the reaction promoted in mild condition. The reaction scope has also been greatly expanded, rendering this copper-based cross-coupling attractive for both academia and industry. This review had been summarized recently advance homogeneous and heterogeneous copper catalyst in Ullmann reaction and its application and natural product and pharmaceutical industry.
  • 2.8K
  • 09 Oct 2020
Topic Review
Microemulsion Design for Acne Therapy
Acne represents a dermatologic condition with a high prevalence, being characterized by a complex pathogenesis. Its high recurrence frequently encountered in clinical practice will affect the patient’s quality of life. Most of the treatment algorithms require at least one topical formulation, being recommended to be applied on affected areas for a long period. To treat such a versatile skin condition, smart topical vehicles capable of entrap anti-acne compounds can be considered a good option, compared with conventional systems generally used at the moment. In this direction, microemulsions are appreciated for their superior profile in matters of drug delivery, especially for challenging substances with hydrophilic or lipophilic patterns. Designed as transparent and thermodynamically stable systems, with a small number of key ingredients, microemulsion-based formulations were characterized in the present review as unique structures able to pass the skin barrier and sustain a targeted therapy in acne pathology.
  • 2.8K
  • 30 Nov 2020
Topic Review
Bioactive Glass
Bioactive glass (BAG) consist of known biocompatible and bioactive minerals, including fluorapatite (FAP), wollastonite, diopside, and tricalcium phosphate. A bioactive material can interact with the biological environment to elicit a specific biological response and they can be osteoconductive or osteoinductive. Bioactive Glasses are amorphous solids with the irregular organization of atoms, optically transparent, and brittle consisting of silica networks. They possesses bioactivity and antimicrobial properties as presented n following sections. The bioactivity of BAGs involves several steps; BAGs immediately undergo ionic dissolution and glass degradation via the exchange of H+ ions in the solution and Na+ and Ca2+ from the glass network. BAG exhibits antimicrobial properties against various pathogens, e.g pathogens associated with sinusitis and osteomyelitis.
  • 2.8K
  • 22 Oct 2020
Topic Review
Citric Acid for Wood Modification
Citric acid (CA) can be found naturally in fruits and vegetables, particularly citrus fruit. CA is widely used in many fields but its usage as a green modifying agent and binder for wood is barely addressed. Esterification is one of the most common chemical reactions applied in wood modification. CA contains three carboxyl groups, making it possible to attain at least two esterification reactions that are required for crosslinking when reacting with the hydroxyl groups of the cell wall polymers. In addition, the reaction could form ester linkages to bring adhesivity and good bonding characteristics, and therefore CA could be used as wood binder too. The environmental impacts and future outlook of CA-treated wood and bonded composite are considered.
  • 2.8K
  • 31 Jul 2020
Topic Review
Shape-Memory Polymers in Dentistry
Objective: To perform a systematic review (SR) of existing literature and a patent landscape report (PLR) regarding the potential applications of shape-memory polymers (SMPs) in dentistry. Search strategy: Clinical and Biomedical online databases (Pubmed, Medline via Embase, Scopus, LILACS, Web of Science, Cochrane Library), Materials Science and Engineering databases (IEEE Explore, Compendex, Proquest), Material Science and Chemical database (Reaxys) so as Patents databases (Questel-Orbit, Espacenet, Patentscope) were consulted as recently as January 2019 to identify all papers and patents potentially relevant to the review. The reference lists of all eligible studies were hand searched for additional published work. Results: After duplicate selection and extraction procedures, 6 relevant full-text articles from the initial 302 and 45 relevant patents from 497 were selected. A modified Consolidated Standards of Reporting Trials (CONSORT) checklist of 14 items for reporting pre-clinical in-vitro studies was used to rate the methodological quality of the selected papers. The overall quality was judged low. Conclusions: Despite the great potential and versatility of SMPs, it was not possible to draw evidence-based conclusions supporting their immediate employment in clinical dentistry. This was due to the weak design and a limited number of studies included within this review and reflects the fact that additional research is mandatory to determine whether or not the use of SMPs in dentistry could be effective. Nevertheless, the qualitative analysis of selected papers and patents indicate that SMPs are promising materials in dentistry because of their programmable physical properties. These findings suggest the importance of furtherly pursuing this line of research.
  • 2.8K
  • 28 Oct 2020
Topic Review
Water-Soluble Photoinitiators in Biomedical Applications
Light-initiated polymerization processes are currently an important tool in various industrial fields. The advancement of technology has resulted in the use of photopolymerization in various biomedical applications, such as the production of 3D hydrogel structures, the encapsulation of cells, and in drug delivery systems. The use of photopolymerization processes requires an appropriate initiating system which, in biomedical applications, must meet additional criteria: high water solubility, non-toxicity to cells, and compatibility with visible low-power light sources. This article is a literature review on those compounds that act as photoinitiators of photopolymerization processes in biomedical applications. The division of initiators according to the method of photoinitiation was described and the related mechanisms were discussed. Examples from each group of photoinitiators are presented, and their benefits, limitations and applications are outlined.
  • 2.8K
  • 10 Jun 2020
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