Nanostructured nonionic thymidine nucleolipid self-assembly materials.
Three nucleoside lipids have been synthesized: 3'-oleoylthymidine, 3',5'-dioleoylthymidine, and 3'-phytanoylthymidine. Differential scanning calorimetry and X-ray diffraction have been employed to characterize the physical properties of these neat lipids. Polarizing optical microscopy, small-angle X-ray scattering, and cryo-transmission electron microscopy techniques have been used to investigate the phase behavior in aqueous systems. Both oleoyl-based nucleoside lipids adopted a lamellar crystalline phase in the neat form at room temperature, and the phytanoyl derivative exhibited a fluid isotropic phase. Under excess water conditions, the presence of one branched (phytanoyl) or one unsaturated (oleoyl) chain promoted the formation of a liquid-crystalline lamellar phase at physiological temperatures. In contrast, the 3',5'-dioleoylthymidine derivative is nonswelling and does not exhibit lyotropic liquid-crystalline phase behavior. The nucleolipids' propensity for DNA-type binding and recognition has been evaluated by using a monolayer system to measure surface pressure-area isotherms in a Langmuir trough and indicates that the nucleoside base is available for nonspecific hydrogen bonding in the monolayer liquid expanded state for the single-chain nucleolipids but not for the dual-chain amphiphile.
CSIRO Materials Science and Engineering, Bag 10, Clayton South MDC, VIC 3169, Australia.
Xavier
X
Mulet
Thomas
T
Kaasgaard
Charlotte E
CE
Conn
Lynne J
LJ
Waddington
Danielle F
DF
Kennedy
Asoka
A
Weerawardena
Calum J
CJ
Drummond
D002152:Calorimetry, Differential Scanning / Q000379:methods; D020285:Cryoelectron Microscopy / Q000379:methods; D003460:Crystallization; D004247:DNA / Q000737:chemistry; D006860:Hydrogen Bonding; D008055:Lipids / Q000737:chemistry*; D046529:Microscopy, Electron, Transmission / Q000379:methods; D008956:Models, Chemical; D049329:Nanostructures / Q000737:chemistry*; D012542:Scattering, Radiation; D013936:Thymidine / Q000737:chemistry*; D014867:Water / Q000737:chemistry; D014965:X-Rays
D008055:Lipids; D014867:Water; D004247:DNA; D013936:Thymidine