title: Structure and conformational dynamics of DMPC/dicationic surfactant and DMPC/dicationic surfactant/DNA systems.
abstract: Amphiphilic dicationic surfactants, known as gemini surfactants, are currently studied for gene delivery purposes. The gemini surfactant molecule is composed of two hydrophilic "head" groups attached to hydrophobic chains and connected via molecular linker between them. The influence of different concentrations of 1,5-bis (1-imidazolilo-3-decyloxymethyl) pentane chloride (gemini surfactant) on the thermotropic phase behaviour of 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC) bilayers with and without the presence of DNA was investigated using Fourier transformed infrared (FTIR) and circular dichroism (CD) spectroscopies, small angle scattering of synchrotron radiation and differential scanning calorimetry. With increasing concentration of surfactant in DMPC/DNA systems, a disappearance of pretransition and a decrease in the main phase transition enthalpy and temperature were observed. The increasing intensity of diffraction peaks as a function of surfactant concentration also clearly shows the ability of the surfactant to promote the organisation of lipid bilayers in the multilayer lamellar phase.
authors.affiliation: Department of Macromolecular Physics, Adam Mickiewicz University, Umultowska 85, Poznań 61-614, Poland. mkozak@amu.edu.pl.
authors.forename: Zuzanna
authors.initials: Z
authors.lastname: Pietralik
authors.forename: Rafał
authors.initials: R
authors.lastname: Krzysztoń
authors.forename: Wojciech
authors.initials: W
authors.lastname: Kida
authors.forename: Weronika
authors.initials: W
authors.lastname: Andrzejewska
authors.forename: Maciej
authors.initials: M
authors.lastname: Kozak
mesh_terms: D002942:Circular Dichroism; D004247:DNA / Q000737:chemistry*; D004134:Dimyristoylphosphatidylcholine / Q000737:chemistry*; D008051:Lipid Bilayers / Q000737:chemistry*; D017550:Spectroscopy, Fourier Transform Infrared; D013501:Surface-Active Agents / Q000737:chemistry*
chemical_list: D008051:Lipid Bilayers; D013501:Surface-Active Agents; D004247:DNA; D004134:Dimyristoylphosphatidylcholine