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What Is Chitosan?
Chitosan is the second most abundant biopolymer in the world, only less than cellulose. It is a versatile biopolymer with unique properties, and is nontoxic, biodegradable and biocompatible. Chitosan is discovered by Rouget in 1859, when the chitin was treated with hot potassium hydroxide solution. At present, chitosan is mainly extracted from shrimp shells or crab shells. Application of Chitosans Chitosan has various applications in a very wide range of fields due to its good biocompatibility, especially in pharmaceuticals (drug delivery, equipment and wound dressings), cosmetics, textile and food industries, and agriculture and the environment industry. Medical Use Chitosan is can used in medical fields. It can be used as a burn dressing and wound healing agent. After dressing…
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Why are Sphingomyelin Liposomes More Popular?
Sphingomyelin is a membrane phospholipid composed of sphingosine, fatty acid, phosphoric acid and nitrogenous bases. Among them, the fatty acyl group and the amino group are connected by an amide bond, and the formed sphingosine is also called ceramide; afterwards, phosphocholine (or phosphoethanolamine) is connected to the C-1 hydroxyl group of ceramide, and then sphingomyelin be composed. Existing studies have shown that the synthesis of sphingomyelin involves the enzymatic transfer of phosphocholine, from phosphatidylcholine to ceramide. The first step in the synthesis of sphingomyelin is the condensation of L-serine and palmitoyl-CoA. Serine palmitoyl transferase catalyzes this reaction. The product of this reaction is reduced to produce dihydrosphingosine. dihydrosphingosine undergoes N-acylation and…
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Oral Nano-drug Delivery System 2
The previous article introduced the relevant information about choosing liposomes and nanoparticles as drug carriers in oral nano-drug delivery systems. This article will continue to introduce the feature of microemulsions, polymers, dendrimers and nano-drug crystals as oral drug carriers. Microemulsion Microemulsion is formed by mixing water phase, oil phase, surfactant and co-surfactant in appropriate proportions, with a particle size of 10~100mpm, transparent or translucent, low viscosity, isotropic thermodynamics and kinetics For a stable oil-water mixing system, there is also literature that the particle size of the microemulsion is 20~200nm. Microemulsions have received extensive attention in recent years because of their significant targeting, sustained-release effects and strong solubilization effects on poorly soluble…
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New Research Develops a New X-ray Responsive Degradation Nano-drug Carrier System
Chemotherapy is a commonly used clinical treatment for tumors, but single-molecule chemotherapeutics have low bioavailability and large side effects, which could be a significant burden to patients and their families. Nanotechnology prepares single-molecule chemotherapeutic drugs into nanometer drugs, which can achieve tumor targeting and controllable release of chemotherapeutic drugs, thereby improving the therapeutic effect and reducing toxic and side effects, which is conducive to achieving high-efficiency and low-toxicity chemotherapy. Mesoporous silica nanomaterials have the advantages of simple synthesis, controllable structure, good chemical tailoring and biocompatibility, and are a nano-medicine carrier platform with good clinical application prospects. According to the characteristics of micro-acid, hypoxia and high redox in the tumor microenvironment, researchers have developed a…
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The Most Cited Literature on Block Copolymer Micelles
Block copolymer micelles are generally formed by the self-assembly of either amphiphilic or oppositely charged copolymers in aqueous medium. In this article, the editor summarizes the most cited research results that scientists have made on block copolymer micelles, and hope you can find what you need. What are Block Copolymer Micelles? Block copolymer micelles are generally formed by the self-assembly of either amphiphilic or oppositely charged copolymers in aqueous medium. The hydrophilic and hydrophobic blocks form the corona and the core of the micelles, respectively. The presence of a nonionic water-soluble shell as well as the scale (10-100 nm) of polymeric micelles are expected to restrict their uptake by the mononuclear phagocyte system and…
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Research Progress of Self-Assembled Drug Delivery Systems 2
Regarding the research progress of self-assembled drug delivery systems, we have introduced the clinical research on acyclovir and didanosine self-assembled systems in previously article. This article will continue to introduce the research results of other drug self-assembly systems, such as zidovudine, isoniazid and gemcitabine self-assembly drug delivery systems. Zidovudine Zidovudine (AZT) is the first anti-HIV drug to be marketed and is still the first-line drug. Nano-preparations of zidovudine include liposomes and nanoparticles. As they may obtain the property of sustained release, lymphatic targeting, and macrophage system targeting,these nano preparations can reduce or eliminate the bone marrow toxicity caused by the distribution of zidovudine in the bone marrow tissue. Since zidovudine, as nucleoside analogs, must be…
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Oral Nano-drug Delivery System 1
With the development of new drug discovery related technologies such as high-throughput screening technology, a large number of drug candidates have been discovered, but their solubility is often low. 40% to 70% of drug candidates are difficult to obtain therapeutic concentrationdue to low solubility and poor oral absorption. In particular, protein and peptide drugs have large molecular weights, are not easy to penetrate biological membranes, are susceptible to the action of enzymes in the organism, and their oral bioavailability is very low. According to the solubility and membrane permeability of the drug, drugs can be divided into 4 categories, namely the Biopharmaceutical Classification System (BCS): Class I is high solubility and high permeability…
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What Is The Clinical Significance Of Extracellular Vesicles
Extracellular vesicles (EVs) are a general term for various vesicles with a lipid bilayer membrane structure that are released under resting or stress conditions. The diameter of the vesicles ranges from tens of nanometers to several micrometers. Almost all living cells release EV, which is found in various biological fluids such as blood, saliva, urine, and the extracellular environment. There is growing evidence that EVs contain maternal-related proteins (such as CD9, CD63, CD81, MHC-I, etc.), lipids, nucleotides, including DNA, messenger RNA (mRNA), microRNA (miRNA), circular RNA (cirRNA) and other non-coding RNAs, and a variety of biologically active substances, are widely involved in the transmission of information between cells through target cell…
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What Everybody Ought To Know About Fluorescent Polymers
In recent years, there are huge demands for fluorescent materials, as they play important roles in various research areas such as chemistry and biology. Due to their fascinating properties and important applications in the fields of materials and life sciences, the research on fluorescent polymers has also attracted extensive scientific attention. In September 2020, polymer researchers from the University of Southern Mississippi, in collaboration with other scientists, have developed fluorescent solids and according to their research, they said that to be the brightest known materials in existence. Their discoveries may be potentially applied in everything from solar energy to medical diagnostics and lasers, and even in autonomous cars. More studies are…
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Want a Quick Q&A for Exosomes? Read This!
In recent years, biomimetic nanomedicine combined with the unique functions of natural biomaterials and the versatility of artificial nanomaterials has attracted widespread attention for drug delivery. In 2019, the study Tumor exosome-based nanoparticles are efficient drug carriers for chemotherapy published in Nature Communications have showed that exosomes-biomimetic nanoparticles have the potential to improve anti-cancer efficacy as drug carriers. Moreover, because such nanoparticles can effectively kill tumor stem cells, it is expected to solve major problems such as tumor recurrence, metastasis and drug resistance. Exosomes are cell vesicles that contain complex RNA and proteins. Their size is in the nanometer range (30-150 nanometers in diameter), and they can be secreted by a variety of cells under…
