title: Changes in Interfacial Tension of a Lipid Membrane Formed at the Water/Chloroform Interface upon DNA Complex Formation.
abstract: Changes in the interfacial tension of a lipid monolayer membrane formed at the water/chloroform interface upon DNA addition were measured using the quasi-elastic laser scattering (QELS) method. A cationic lipid, N-[1-(2,3-dioleoyloxy)propyl]-N,N,N-trimethylammonium chloride (DOTAP), as well as zwitterionic lipids, 1,2-dioleoyl-sn-glycero-3-phosphoethanolamine (DOPE) and 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC), were used to form lipid monolayer membranes at different calcium ion concentrations. A rapid decrease of the interfacial tension resulting from electrostatic interactions between DOTAP and DNA was observed within 10 s. However, such rapid decreases were not observed for DOPE or DOPC. A decrease in the interfacial tension was exhibited by DOPE after 1000 s from the addition of DNA, which may be due to an overall structural change in the DOPE membrane. A DOTAP/DOPE complex system showed behaviors attributable to both DOTAP and DOPE, whereas the behavior of the DOTAP/DOPC system resembled that of DOPC alone. The current results provide a model for the so-called lipoplex carriers used in gene therapy.
authors.affiliation: Department of Applied Chemistry and Biotechnology, Chiba University.
authors.forename: Masashi
authors.initials: M
authors.lastname: Ohno
authors.forename: Taro
authors.initials: T
authors.lastname: Toyota
authors.forename: Tomonori
authors.initials: T
authors.lastname: Nomoto
authors.forename: Masanori
authors.initials: M
authors.lastname: Fujinami
mesh_terms: D002122:Calcium Chloride / Q000737:chemistry; D002462:Cell Membrane / Q000737:chemistry*; D002725:Chloroform / Q000737:chemistry*; D004247:DNA / Q000737:chemistry*; D005229:Fatty Acids, Monounsaturated / Q000737:chemistry; D010713:Phosphatidylcholines / Q000737:chemistry; D010714:Phosphatidylethanolamines / Q000737:chemistry; D000644:Quaternary Ammonium Compounds / Q000737:chemistry; D013500:Surface Tension; D014867:Water / Q000737:chemistry*
chemical_list: C410262:1,2-dioleoyl-glycero-3-phosphatidyl ethanolamine; D005229:Fatty Acids, Monounsaturated; D010713:Phosphatidylcholines; D010714:Phosphatidylethanolamines; D000644:Quaternary Ammonium Compounds; D014867:Water; D002725:Chloroform; D004247:DNA; C017251:1,2-oleoylphosphatidylcholine; D002122:Calcium Chloride; C070046:1,2-dioleoyloxy-3-(trimethylammonium)propane