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What Are The Influencing Factors of Drug Percutaneous Absorption
In the clinical transdermal drug delivery process, there are many factors that affect the transdermal absorption of the drug, mainly including: skin hydration, skin temperature, skin conditions, and skin locations. Skin Hydration The phenomenon that the water content of the skin exceeds the normal state is called skin hydration. After the skin is saturated with water, the tissue softens, swells, wrinkles disappear, and the permeability increases significantly. Skin hydration promotes transdermal absorption of drugs. The encapsulation method or the application of ointment on the skin reduces the evaporation of skin moisture, and the covering effect increases the endogenous hydration of the stratum corneum and increases skin penetration. The hydration of the stratum corneum can…
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How Does the Drug Enter the Human Body Through the Skin?
Transdermal drug delivery systems in a broad sense include topical drug delivery systems and transdermal drug delivery systems (TDDS). The former acts on the skin or subcutaneous tissue; the latter is the absorption of drugs into the blood through the skin. Compared with oral or injection administration, the advantages of the transdermal drug delivery system include: 1. No gastrointestinal irritation; 2. Avoid the first pass effect of the liver 3. Get a controlled release effect; 4. Easy to use, good patient compliance; 5. High safety , Easy to remove; 6. less skin tissue degrading enzymes, can be used for the administration of macromolecular drugs. Global sales of transdermal drug delivery preparations reached US$12.7 billion in 2005, US$21.5 billion in…
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In Vitro Evaluation Method of Oral Nano Drug Delivery System
The in vitro evaluation method of oral nano-drug system is a simple and rapid method to evaluate the transport and absorption of oral nano-drug. This method is simple and easy to implement, has good reproducibility, and the experimental environment and conditions are easy to control, so that the influencing factors are singularized and simplified, but it cannot reflect the actual absorption state of the drug in the body. This method is often used to study the intestinal absorption mechanism of the nano drug delivery system. The method mainly includes inverted intestinal sac method, intestinal piece incubation method, membrane vesicle method, cell culture model method, parallel artificial membrane permeability determination method, computer…
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Carrier And Biological Level Evaluation Method of Oral Nano-Drug Delivery System
The oral nano-drug system is evaluated at the body level mainly through intact animals, which have complete blood supply and innervation to ensure that the intestinal nerves are intact and directly reflect drug absorption. This evaluation method can be used to study drug penetration and absorption kinetics. The related detection methods mainly include: in vivo intestinal perfusion method, intestinal loop method, intestinal vascular intubation method and nitrogen measurement method. Intestinal Perfusion In vivo intestinal perfusion is to insert a double-lumen tube into the intestine through the mouth (in experimental animals, the perfusion tube and the drainage tube are inserted into the proximal and distal ends of the intestine respectively through…
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Want A Quick Understanding for Your Dendrimers?Read This!
What Are Dendrimers? Dendrimers are nano-sized, radially symmetric molecules with well-defined, homogeneous, and monodisperse structure consisting of tree-like arms or branches. These hyperbranched molecules were first discovered by Fritz Vogtle in 1978, by Donald Tomalia and co-workers in the early 1980s, and at the same time, but independently by George R. Newkome. A variety of dendrimers exist, and each has biological properties such as polyvalency, self-assembling, electrostatic interactions, chemical stability, low cytotoxicity, and solubility. These varied characteristics make dendrimers a good choice in the medical field, and support their diverse applications, such as drug delivery, gene delivery, magnetic resonance imaging contrast agents, and photodynamic therapy. Are Dendrimers Polymers? Dendrimers are synthetic polymeric…
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Oral Nano Drug Delivery System Absorption Mechanism
Oral absorption of nanomedicine means that nanomedicine enters the blood circulation through the gastrointestinal tract. Nanomedicine has a very complicated process after entering the body, interacting with the components in the biological system (such as proteins and cells), and has unique distribution, clearance, metabolism and immune response behaviors in the body. There are three main ways for nanoparticles to be absorbed in the gastrointestinal tract: 1. Cell bypass channel transport; 2. Transcellular uptake by intestinal epithelial cells; 3. Phagocytosis by microfold cells (M cells) in Peyer’s patches in the ileum. Absorption through M cells is the main absorption route of oral nanoparticles. When the nanoparticles enter the gastrointestinal tract, part…
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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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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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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…
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In Vivo Characteristics of Antitumor Drug Liposomes
Anti-tumor drug liposomes need to be studied in vivo during the development process, which includes examination of liposome pharmacokinetics, clinical efficacy and in vivo safety. Pharmacokinetics Liposomes have a greater influence on the pharmacokinetic parameters of drug-loaded drugs, which are characterized by increased AUC(area under the curve, it shows drug’s bioavailabilit), extended half-life period, decreased clearance, decreased volume of distribution, and changes in tissue distribution. The pharmacological changes can be explained and proven from the anatomical characteristics of tumor sites, structural characteristics of liposomes, non-clinical studies and clinical studies. The targeting of liposomes is divided into passive targeting, physicochemical targeting and active targeting. These targeting effects make the pharmacokinetic behavior of liposome…
