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Sucrose Polymer Overview
Sucrose is a disaccharide with a unique structure. It is a non-reducing sugar formed by removing a molecule of water from the glycoside hydroxyl group of a molecule of α-D-(+)-glucopyranose and a molecule of β-D-(-)-fructofuranose. During the hydrolysis process, the specific optical rotation of sucrose gradually changes from dextrorotatory to levorotatory, so the hydrolysis of sucrose is also commonly referred to as a conversion reaction. There are 8 chemically active hydroxyl groups and glycosidic bonds in the sucrose molecule, through which these groups can theoretically undergo oxidation, reduction, decomposition, esterification, polycondensation, etherification, substitution, degradation, etc. with other compounds or itself. This reaction provides the possibility to form a wide variety…
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What Are D-Glucosamines?
Glucosamine is a natural component of cartilage and is widely used as an over-the-counter nutritional supplement to reduce the pain and cartilage loss of osteoarthritis. Glucosamine is usually taken in combination with chondroitin, which is a glycosaminoglycan that also exists in cartilage. Glucosamine is an amino sugar and an important molecule in the biochemical pathway of glycosylated protein and lipid synthesis. It is also the main component of keratin sulfate and hyaluronic acid present in articular cartilage and synovial fluid. Both glucosamine and chondroitin are reduced in osteoarthritis. Clinically, active supplementation of glucosamine and chondroitin can relieve the symptoms of arthritis. Therefore, it is widely used to treat osteoarthritis and…
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Research on Metal Nanoclusters in the Field of Biomedicine
Due to the excellent characteristics of metal nanoclusters, they have many applications in the field of biomedicine. Current research shows that metal nanoclusters have good application value in biosensors, nucleic acid and protein molecular detection. Application of Metal Nanoclusters in Biosensing Metal nanoclusters have excellent fluorescence and catalytic properties, and are ideal fluorescent and chromatic signal probes. At the same time, the specific interaction between metal nanoclusters and analytes can cause the change of metal cores, ligand shells or the surrounding microenvironment. The change causes a change in performance. Therefore, the metal nanoclusters integrate the identification element and the signal conversion element as a whole, and the biosensor constructed therefrom…
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What are Metal Nanoclusters
Metal nanoclusters are a kind of nanomaterials with a size of less than 2 nm and stacked by 1 to 150 metal atoms. Metal nanoclusters have a typical core-shell structure, consisting of a metal atomic core and a ligand molecular shell. Ligands are usually substances that have strong covalent interaction with metal atoms such as amino groups, sulfhydryl groups, and phosphorus groups, such as thiol compounds, dendrimers, polymers, deoxyribonucleic acid (DNA), polypeptides, and proteins. At present, gold nanoclusters (AuNCs), silver nanoclusters (AgNCs), platinum nanoclusters (PtNCs), copper nanoclusters (CuNCs) and other metal nanoclusters have been widely synthesized. In recent years, metal nanoclusters have made remarkable achievements in biomedical fields such as…
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What Are Dextrans?
Dextran is a polysaccharide comprised of d-glucopyranose (d-glucose) repeating units linked through glycosidic linkages. It is biocompatible, biodegradable, and presents antithrombotic and anti-inflammatory properties. Dextran functional hydroxyl (–OH) groups offer an easy point for chemical conjugation with other materials. As an example, dextran can be modified with hydrophobic moieties in order to form dextran-based amphiphiles. These amphiphilic materials can encapsulate poorly water-soluble chemotherapeutics through hydrophobic interactions and self-assemble into nanocarriers. What Are the Chemical Structure and Properties of Dextrans? Dextran consists of α(1,6)-linked glucan with side chains attached to the C-3 position of the backbone (Figure 1). It is synthesized from sucrose by certain lactic acid bacteria, such as leuconostoc…
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What Is Polylactide?
Polylactide (PLA), also the polylactic acid, is the biodegradable hydrolyzable aliphatic semicrystalline polyester that can be produced through the direct condensation reaction of its monomer, lactic acid, as the oligomer, and also by a ring-opening polymerization of the cyclic lactide dimer. Is Polylactic Acid Natural? PLA is a biodegradable, biocompatible, and renewable thermoplastic polyester. The monomer lactic acid (LA) of PLA is derived from natural sources, which is produced using bacterial fermentation of corn, sugarcane, potatoes, sugar beet pulp, and other biomass. What Are the Characteristics of Polylactide? PLA is a very useful material to be used as a replacement for petroleum-based polymers because of its good mechanical properties and…
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What Are Macrocycles?
Macrocycles are generally described as molecules and ions containing twelve- or more-membered rings. Macrocyclic compounds describe a large and mature field of chemistry. The macrocycle often binds ions and facilitates the transport of ions across the hydrophobic membrane and solvent. It wraps the ions with a hydrophobic sheath, which facilitates the phase transfer characteristics. What Are Macrocyclic Effects? The macrocyclic effect is when the multidentate ligand forms a ring with the central metal atom or ion, since it is a multidentate ligand, the stability of the complex is enhanced. The macrocyclic effect is the high affinity of metal cations for macrocyclic ligands compared to their acyclic analogs. What Is a…
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What Are Chelating Agents?
Chelating agents are organic compounds capable of linking together metal ions to form complex ring-like structures called chelates. They are also known as chelants, chelators, or sequestering agents. What Are Natural Chelating Agents? Citric, malic, lactic, and tartaric acids and certain amino acids are naturally occurring chelating agents, but they are not as powerful as EDTA. The EDTA (ethylene-diamine-tetraacetic acid) molecule is a chelating agent widely used in molecular biology to sequester divalent and trivalent metal ions such as calcium and magnesium. What Is a Typical Chelating Agent? An example of a simple chelating agent is ethylenediamine. A single molecule of ethylenediamine can form two bonds to a transition-metal ion…
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What is Nano Dressing
Nanotechnology has not only received attention and applications in the field of drug delivery, but also has achieved many successes in the field of tissue engineering. Nano dressings can be defined as dressings in which nanomaterials are the matrix. The birth of nano dressings has brought new treatment methods for wound repair and burn care, such as nanohydrogels, nanofibers, nanomembranes, dendrimers, and polymer conjugates (acting as drugs release in the process of wound treatment, growth factor supplementation and/or artificial skin effect). The role of nano-dressing includes anti-bacterial and anti-inflammatory, acting on tissue functional cells, optimizing and improving the matrix, and promoting the proliferation and differentiation of stem cells. Features of…
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What is microneedle
Microneedles are delicate clusters of fine needles made by micro-manufacturing technology. The length is 1-150μm, which is enough to penetrate the stratum corneum or active epidermis of human skin, but does not touch the nerves, has no pain, and has continuous promotion of drug transdermal delivery. Microneedle technology has the comprehensive characteristics of subcutaneous injection and ordinary transdermal patches. Its advantages include: 1. It can deliver macromolecules through the stratum corneum, and is suitable for the transdermal delivery of peptides, proteins and other macromolecular drugs, and even drug-loaded nanoparticles; 2. Compared with the painful subcutaneous injection, the microneedle is almost non-invasive and painless, and has good patient compliance; 3. The…
