Liposome

Scheme of a liposome formed by phospholipids in an aqueous solution.
Liposomes are composite structures made of phospholipids and may contain small amounts of other molecules. Though liposomes can vary in size from low micrometer range to tens of micrometers, unilamellar liposomes, as pictured here, are typically in the lower size range with various targeting ligands attached to their surface allowing for their surface-attachment and accumulation in pathological areas for treatment of disease.[1]

A liposome is a small artificial vesicle, spherical in shape, having at least one lipid bilayer.[2] Due to their hydrophobicity and/or hydrophilicity, biocompatibility, particle size and many other properties,[2] liposomes can be used as drug delivery vehicles for administration of pharmaceutical drugs and nutrients,[3] such as lipid nanoparticles in mRNA vaccines, and DNA vaccines. Liposomes can be prepared by disrupting biological membranes (such as by sonication).

Liposomes are most often composed of phospholipids,[4] especially phosphatidylcholine, and cholesterol,[2] but may also include other lipids, such as those found in egg and phosphatidylethanolamine, as long as they are compatible with lipid bilayer structure.[5] A liposome design may employ surface ligands for attaching to desired cells or tissues.[1]

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).[6] The major types of liposomes are the multilamellar vesicle (MLV, with several lamellar phase lipid bilayers), the small unilamellar liposome vesicle (SUV, with one lipid bilayer), 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.

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))[7].

Liposomes should not be confused with lysosomes, or with micelles and reverse micelles.[8] In contrast to liposomes, micelles typically contain a monolayer of fatty acids or surfactants.[9]

  1. ^ a b Torchilin, V (2006). "Multifunctional nanocarriers". Advanced Drug Delivery Reviews. 58 (14): 1532–55. doi:10.1016/j.addr.2006.09.009. PMID 17092599. S2CID 9464592.
  2. ^ a b c Akbarzadeh, A.; Rezaei-Sadabady, R.; Davaran, S.; Joo, S. W.; Zarghami, N.; Hanifehpour, Y.; Samiei, M.; Kouhi, M.; Nejati-Koshki, K. (22 February 2013). "Liposome: classification, preparation, and applications". Nanoscale Research Letters. 8 (1): 102. Bibcode:2013NRL.....8..102A. doi:10.1186/1556-276X-8-102. ISSN 1931-7573. PMC 3599573. PMID 23432972.
  3. ^ "Cell Membranes - Kimball's Biology Pages". 16 August 2002. Archived from the original on 25 January 2009.
  4. ^ Mashaghi S., et al. Lipid Nanotechnology. Int J Mol Sci. 2013 Feb; 14(2): 4242–4282.
  5. ^ Cevc, G (1993). "Rational design of new product candidates: the next generation of highly deformable bilayer vesicles for noninvasive, targeted therapy". Journal of Controlled Release. 160 (2): 135–146. doi:10.1016/j.jconrel.2012.01.005. PMID 22266051.
  6. ^ Moghassemi, Saeid; Dadashzadeh, Arezoo; Azevedo, Ricardo Bentes; Feron, Olivier; Amorim, Christiani A. (November 2021). "Photodynamic cancer therapy using liposomes as an advanced vesicular photosensitizer delivery system". Journal of Controlled Release. 339: 75–90. doi:10.1016/j.jconrel.2021.09.024. PMID 34562540. S2CID 237636495.
  7. ^ Moghassemi, Saeid; Dadashzadeh, Arezoo; Azevedo, Ricardo Bentes; Feron, Olivier; Amorim, Christiani A. (November 2021). "Photodynamic cancer therapy using liposomes as an advanced vesicular photosensitizer delivery system". Journal of Controlled Release. 339: 75–90. doi:10.1016/j.jconrel.2021.09.024. PMID 34562540. S2CID 237636495.
  8. ^ Stryer S. (1981) Biochemistry, 213
  9. ^ Mashaghi S., et al. Lipid Nanotechnology. Int J Mol Sci. 2013 Feb; 14(2): 4242–4282.