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What Are Sphingolipids?
Sphingolipids are the most structurally diverse class of membrane lipids, being composed of over 70 long-chain (sphingoid) bases, dozens of amide-linked fatty acids, and more than 300 headgroups. Sphingolipids are present in all eukaryotic and some prokaryotic organisms. 1.What Is The Function Of A Sphingolipid? Sphingolipids are highly bioactive compounds that participate in the regulation of cell growth, differentiation, diverse cell functions, and apoptosis. Sphingolipids are both structural and functional lipids. Their physical properties (such as high phase transition temperatures) affect the properties of membranes and lipoproteins, and they are critical components of the water barrier of skin. Besides, they serve as ligands for extracellular matrix proteins and receptors on…
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Protein Peptide Drug Lung Inhalation Nano Preparation
Pulmonary administration has great advantages as a non-invasive route of administration of protein and peptide drugs. The human respiratory tract has a large surface area, which can avoid the first pass effect of the liver. In addition, the viscosity of the epithelial cell barrier is low, and there is a large amount of potential vasculature, low proteolytic activity and low acidity. Compared with the gastrointestinal tract, there is a thinner mucus layer, so the lungs are suitable for local and systemic administration. However, the mucosa of the respiratory tract is very tight and complex, and it is difficult for macromolecular drugs to penetrate. In fact, a single macromolecule is difficult…
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Chemical Medicine Lung Inhalation Nano Preparation
At present, a variety of chemical drugs are combined with nano-carriers to make lung-inhaled nano-preparations, and have achieved good results, such as anti-tuberculosis drugs, itraconazole, terbutaline sulfate, ciprofloxacin, curcumin and Camptothecin. Anti-tuberculosis drugs Polylactic acid glycolic acid (PLGA) has good biodegradability and biocompatibility, and is widely used as a drug carrier. The pulmonary tuberculosis drugs rifampicin, isoniazid, and pyrazinamide are prepared by the double emulsion/solvent volatilization method to prepare PLGA nanoparticles for pulmonary administration. The particle size is 180-300m, and the encapsulation rate is 50%- 70%. Rifampicin PLGA nanoparticles were prepared by a double emulsion method, and the nanoparticles were dissolved in an alginic acid solution and spray-dried to obtain nano-mixed particles with…
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What Are Monomers?
Monomers are molecules that can react together with other monomer molecules to form a larger polymer chain or three-dimensional network in a process called polymerization. There are mainly four types of monomers, including sugars, amino acids, fatty acids, and nucleotides, and each of these monomer types plays an important role in the existence and development of life, and each can be synthesized through abiotic means. What Are Monomers Made? Polymers are synthetic substances that consist of multiple simpler units called monomers. A polymer is a chain with an indefinite number of monomer units. Homopolymers are polymers made by joining together monomers with the same chemical composition or structure. How Do You Identify Monomer?…
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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. Block copolymer micelles can be classified according to the type of intermolecular forces driving the segregation of the core segment from the aqueous milieu. In the past few decades, at least three main categories were identified, viz. amphiphilic micelles (formed by hydrophobic interactions), polyion complex micelles (PICM; resulting from electrostatic interactions), and micelles stemming from metal complexation. Generally, when the hydrophilic segment is longer than the core block, the shape of the resulting micelles is spherical. Conversely, increasing…
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Lung Inhalation Nano Drug Delivery System Dosage Form
The existing pulmonary inhalation nano drug delivery system dosage forms are mainly divided into two types: liposomes and nanoparticles. Liposomes Among the various dosage forms for pulmonary administration, liposomes have obvious advantages, such as being suitable for encapsulating lipophilic drugs, avoiding local irritation, enhancing curative effects, reducing toxic and side effects, and evenly distributing active drugs in the lungs. Lung-administered liposomes can also be used for gene therapy. Compared with viral vectors, liposomes are simple to prepare, have no damage to normal tissues, and have high safety. Liposome pulmonary drug delivery has the following characteristics: 1. The main component of alveoli is lipids, among which phospholipids account for 80% of…
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Influencing Factors of Particulate Pulmonary Deposition
The deposition of particles in the lungs is affected by particle characteristics (particle size distribution, morphology, roughness, porosity), carriers, drugs, and breathing methods. Particle Size and Shape Particle size, particle morphology, and particle density are important factors that determine lung deposition. Particles of different aerodynamic diameters (Dae) collide, settle and diffuse inertially when entering the lungs. Dae is an imaginary particle size that describes the movement of particles. It is defined as: to make the unit density sphere moving at low Reynolds number in still air, and the actual diameter reached the same final particle sedimentation rate, which is the actual particle size in terms of equivalent aerodynamic characteristics of the same diameter, that…
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What Are Natural Phospholipids?
Lipids are defined as apolar molecules comprising as major classes fatty acids and fatty acid esters of normally natural origin. Non-natural components, such as dicarba-closo-dodecaboranes (in short carboranes) can also form acids and esters, which reveal lipid-like properties. Phospholipids are lipids usually composed of three components: a diglyceride, a phosphate group and another organic molecule such as choline, to produce phosphatidylcholine. Phospholipids are a major component of all cellular membranes and can form bilayers. What Are Examples of Phospholipids? The most common phospholipids are phosphatidylcholine, phosphatidylethanolamine, phosphatidylinositol, and phosphatidylserine. These phospholipids share the common features of fatty acids esterified to the 1 and 2 positions of the glycerol backbone with the phosphate…
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What Are PEGs?
PEGs (polyethylene glycols) are composed of polyether compounds repeating ethylene glycol units according to the constituent monomer or parent molecule (as ethylene glycol, ethylene oxide, or oxyethylene) (Fig. 1). Most PEGs are commonly available commercially as mixtures of different oligomer sizes in molecular weight (MW) ranges. For instance, PEG-10,000 typically designates a mixture of PEG molecules (n = 195 to 265) having an average MW of 10,000. PEG is also known as polyethylene oxide (PEO) or polyoxyethylene (POE), with the three names being chemical synonyms. However, PEGs mainly refer to oligomers and polymers with molecular masses below 20,000 g/mol, while PEOs are polymers with molecular masses above 20,000 g/mol, and POEs are…
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Liposomes for Cosmetics
Liposomes are spherical vesicles in which their central aqueous section is surrounded by one or more of a bilayer membrane (Lamella) that is frequently enclosed by aquatic environments. These vesicles are formed when amphiphilic lipids confront with aqueous milieu. They can vary in size from 15 nm to several microns. In the last 30 years, the application of liposome has been expanded from drug delivery to the cosmetic field and it is the most widely known cosmetic delivery system nowadays. What AreLiposomes in Cosmetics? Liposomes can act as dermal delivery carriers due to their being small, unilamellar, and designed with membrane flexibility. Therefore, liposomes are commonly used in dermal applications, either as protective…
