title: DNA-induced aggregation of zwitterionic oligolamellar liposome.
abstract: Liposome consisting of a single zwitterionic lipid as the potential vector for gene therapy has been reported recently; however, whether polyanionic DNA can bind directly with zwitterionic lipid without the aid of multivalent salt still remains unresolved. In this study, we reveal the aggregation of zwitterionic oligolamellar liposomes composed of 1,2-di(cis-9-octadecenoyl)-sn-glycero-3-phosphocholine induced by DNA without the presence of multivalent salt. Our results demonstrate that only a small fraction (<10%) of DNA can bind electrostatically with a portion of the liposomes. Such a low degree of binding, however, induces significant aggregation of these oligolamellar liposomes, yielding large multilamellar particles in which the number of hydrophilic/hydrophobic layer stacking becomes sufficiently large to yield multiple diffraction peaks in the small-angle X-ray scattering profile. Addition of monovalent salt such as NaCl tends to disrupt the multilamellar structure.
authors.affiliation: Department of Chemical Engineering, National Tsing Hua University, Hsin-Chu, Taiwan 30013, Republic of China.
authors.forename: Ching-Mao
authors.initials: CM
authors.lastname: Wu
authors.forename: Hsin-Lung
authors.initials: HL
authors.lastname: Chen
authors.forename: Willisa
authors.initials: W
authors.lastname: Liou
authors.forename: Tsang-Lang
authors.initials: TL
authors.lastname: Lin
authors.forename: U-Ser
authors.initials: US
authors.lastname: Jeng
mesh_terms: D001672:Biocompatible Materials / Q000737:chemistry*; D002412:Cations; D004247:DNA / Q000737:chemistry*; D004337:Drug Carriers; D015316:Genetic Therapy / Q000379:methods*; D005822:Genetic Vectors; D008027:Light; D008055:Lipids / Q000737:chemistry; D008081:Liposomes / Q000737:chemistry*; D046911:Macromolecular Substances / Q000737:chemistry; D046529:Microscopy, Electron, Transmission; D010713:Phosphatidylcholines / Q000737:chemistry; D012542:Scattering, Radiation; D012965:Sodium Chloride / Q000737:chemistry; D013053:Spectrophotometry; D055672:Static Electricity; D014466:Ultraviolet Rays; D014867:Water / Q000737:chemistry; D014965:X-Rays
chemical_list: D001672:Biocompatible Materials; D002412:Cations; D004337:Drug Carriers; D008055:Lipids; D008081:Liposomes; D046911:Macromolecular Substances; D010713:Phosphatidylcholines; D014867:Water; D012965:Sodium Chloride; D004247:DNA; C017251:1,2-oleoylphosphatidylcholine