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Brief Introduction of Xanthan Gum
Xanthan gum, also known as yellow gum, is white or light yellow powder. In 1952, it was isolated and extracted from the pathogenic strain of Xanthomonas campestris by the northern laboratory of the United States. After in-depth research, it was found that xanthan gum has excellent rheological properties and can partially or completely replace other gloea. Since then, xanthan gum has been extensively studied. Xanthan gum was discovered in 1954, and it has been industrialized for less than 70 years since 1964. It has become one of the most widely used biological gums in the world, and has been used in food, petroleum, and pharmaceutical fields. Xanthan Gum Structure Xanthan…
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Research Progress of Pectin and Its Medical Application
Pectin is a hydrophilic vegetable gum. Widely present in the fruits, roots, stems and leaves of higher plants, it is a component of the cell wall. The pectin content of different plants or different parts of the same plant varies greatly. So far, only a few plants with high pectin content have been found and used as raw materials for industrial production, mainly citrus peels, sunflower trays, and sugar beets. Pectin is the general term for protopectin, pectin and pectic acid. Protopectin is insoluble in water and only exists in the cell wall; pectin is soluble in water and exists in the cell juice; pectin acid is slightly soluble in…
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Gene Carrier Based on Nanomaterials
Gene therapy refers to the introduction of normal foreign genes into target cells to compensate or correct diseases caused by gene defects or abnormalities, so as to achieve the purpose of treatment. Naked DNA usually requires physical methods to enter tissues or cells, and DNA is easily digested and degraded by various enzymes in tissues or cells, resulting in a very low expression level of the encoded protein, which affects the effect of gene therapy. Therefore, the development of gene carriers with low toxicity and high efficiency is one of the urgent problems to be solved in gene therapy. Gene vectors are generally divided into two categories: viral vectors and…
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Research Progress of PROTAC in the Treatment of Malignant Tumors
Malignant tumors are a major global public health problem, the leading cause of death in developing countries and the second leading cause of death in developed countries. Traditional treatment methods such as surgical resection, radiotherapy and chemotherapy have serious side effects on the body. Tumor immunotherapies such as small molecule inhibitors and monoclonal antibodies act on the body’s immune system to remove tumor cells and reduce the immunosuppressive signals caused by tumor cells, and achieve good clinical results. However, tumor cells are prone to gene mutations to escape immune surveillance, and small molecule inhibitors are prone to drug resistance and off-target effects. Monoclonal antibodies have large molecular weights, are difficult…
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A Review of Proteolytic Targeting Chimeras
The concept of proteolytic targeting chimera (PROTAC) was first proposed by Crews and Deshaies laboratory in 2001, the team successfully achieved the degradation of methionyl aminopeptidase 2 (MetAp-2) by PROTAC method. Since then, PROTACs targeting androgen receptor (AR) and estrogen receptor (ER) have appeared one after another. In 2004, a PROTAC molecule that recruited the tumor suppressor protein VHL through a polypeptide fragment on HIF1-α showed a greater improvement in membrane permeability and could also exist stably in cells. However, these peptide-based PROTAC molecules were not ready for drug preparation. Until 2008, when the first small-molecule E3 ubiquitinase ligand-based PROTAC came out, marking the beginning of small-molecule PROTAC research, and…
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The Function of Drug Coating
Coating refers to the unit operation of applying a layer of outer coating material to the dry surface of the formulation. This coating material not only makes the product easier to identify, but even improves the pharmacokinetic properties of the drug by altering its release: ensuring that the drug reaches its target and provides sufficient concentrations in the body to be maintained for an extended period of time. Coatings are widely used in oral solid dosage forms, including tablets, capsules, multi-particulates and drug crystals. However, the most common coated dosage form is the tablet, followed by the coated multi-particulate dosage form. Reasons for using coating drug dosage forms vary, but…
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A Short Biography of Carbon Dots
Carbon dots (CDs) are a new type of zero-dimensional fluorescent nanomaterials with a size of less than 10 nm, which are composed of a graphitized sp2 carbon core and a shell containing abundant groups such as amino groups, ether groups, carbonyl groups, and hydroxyl groups on the surface, has the advantages of easy preparation, low toxicity, stable optical properties and no photobleaching. Since its discovery in 2004, the preparation, luminescence mechanism and application of CDs have been the hotspot of research. CDs preparation methods are divided into top-down and bottom-up methods, covering electrochemical oxidation, laser ablation, hydrothermal, pyrolysis, and microwave methods. Hydrothermal and microwave methods are favored by simple and…
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Advantages of Liposomal in Drug Delivery
Liposomes are ultra-micro spherical carrier preparations formed by lipid bilayers, and are typical representatives of nano-drug delivery systems. When amphiphilic molecules such as phospholipids are dispersed in the aqueous phase, the hydrophobic tails of the molecules gather together, and the hydrophilic heads are exposed in the aqueous phase to form closed vesicles with a bilayer structure. A variety of drugs of different polarities can be encapsulated in the water phase and bimolecular membrane in the vesicles. In addition, liposomes have good biocompatibility and can be normally metabolized. Therefore, liposomes have great potential for development as drug carriers. The mechanism of action of the liposome drug delivery system can be divided…
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Metal-organic Frameworks and Novel Drug-Carrying Systems
Metal-organic frameworks (MOFs) form long-range ordered geometric structures through the coordination and binding of metal ions and small organic molecules, changing metal elements and small organic molecules, resulting in an ever-expanding family of MOFs. Due to their excellent properties such as low density, high specific surface area, high porosity, tunable pore size and morphology, and topological diversity, MOFs have broad application prospects in the field of drug delivery. As a drug carrier, MOFs can not only protect the drug, but also improve the human body’s absorption, release and metabolism of the drug, and enhance the therapeutic effect of the drug, which has potential advantages. Introduction to MOFs In 1995, Yaghi…
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What are Biopolymers?
Biodegradable polymers are most often referred to as “biopolymers” because most of these polymers are derived from various natural sources. There are few in the list of biodegradable biopolymers in nature. PLA, PHA and starch are the most commonly used biopolymers that have minimal or minimal impact on the increasing environmental carbon footprint. However, biodegradability is a characteristic of polymers that is independent of their origin and can be altered after tuning at the molecular level. Therefore, some polymers are produced from petroleum feedstocks but are biodegradable. Therefore, in addition to naturally derived biopolymers, there are also petroleum-based biodegradable biopolymers. Natural Biopolymer Natural biopolymers are natural polymers produced by living…
