Liposome

A liposome is a small artificial <a href="/facts/Vesicle_(biology_and_chemistry)/1KjHpjMM">vesicle</a>, spherical in shape, having at least one <a href="/facts/Lipid_bilayer/CQKQ9l3g">lipid bilayer</a>. Due to their hydrophobicity and/or hydrophilicity, biocompatibility, particle size and many other properties, liposomes can be used as <a href="/facts/Drug_delivery/vDfboXeT">drug delivery</a> vehicles for <a href="/facts/Route_of_administration/LsyoHTzH">administration</a> of <a href="/facts/Pharmaceutical_drug/h9mhwWP2">pharmaceutical drugs</a> and <a href="/facts/Nutrient/34bn4skK">nutrients</a>, such as <a href="/facts/Solid_lipid_nanoparticles/h9poKr1E">lipid nanoparticles</a> in <a href="/facts/MRNA_vaccine/PCUBVuSw">mRNA vaccines</a>, and <a href="/facts/DNA_vaccination/qlmX0fwQ">DNA vaccines</a>. Liposomes can be prepared by disrupting biological membranes (such as by <a href="/facts/Sonication/RfKqX7t4">sonication</a>).
Liposomes are most often composed of <a href="/facts/Phospholipid/u6GhNCF5">phospholipids</a>, especially <a href="/facts/Phosphatidylcholine/WCHvJfdY">phosphatidylcholine</a>, and <a href="/facts/Cholesterol/TnfPlYc1">cholesterol</a>, but may also include other lipids, such as those found in <a href="/facts/Egg_(food)/dRLxAGev">egg</a> and <a href="/facts/Phosphatidylethanolamine/A5Q6bSVk">phosphatidylethanolamine</a>, as long as they are compatible with <a href="/facts/Lipid_bilayer/CQKQ9l3g">lipid bilayer</a> structure. A liposome design may employ surface <a href="/facts/Ligand/6etB3qeW">ligands</a> for attaching to desired cells or tissues.
Based on vesicle structure, there are seven main categories for liposomes: multilamellar large (MLV), oligolamellar (OLV), small unilamellar (SUV), medium-sized unilamellar (MUV), large unilamellar (LUV), giant unilamellar (GUV) and multivesicular vesicles (MVV). The major types of liposomes are the multilamellar vesicle (MLV, with several <a href="/facts/Lamellar_phase/9ncNXdpE">lamellar phase</a> <a href="/facts/Lipid_bilayer/CQKQ9l3g">lipid bilayers</a>), the small <a href="/facts/Unilamellar_liposome/7HRSs5tN">unilamellar liposome</a> vesicle (SUV, with one <a href="/facts/Lipid_bilayer/CQKQ9l3g">lipid bilayer</a>), the large unilamellar vesicle (LUV), and the cochleate vesicle. A less desirable form is multivesicular liposomes in which one vesicle contains one or more smaller vesicles.

Liposomes should not be confused with <a href="/facts/Lysosome/0mcrzJU9">lysosomes</a>, or with <a href="/facts/Micelle/eMG9whea">micelles</a> and <a href="/facts/Micelle/eMG9whea">reverse micelles</a>. In contrast to liposomes, micelles typically contain a monolayer of fatty acids or surfactants.

Liposome open-in-new

Liposome