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A thermodynamic study of the driving forces of phase transitions in surfactant and lipid system is presented. The driving forces of phase transitions can be determined from the appearance of the phase diagram using the approach based on van der Waals differential equation.

The effect of four non-bilayer forming lipids on the stability of phosphatidylcholine (PC, a bilayer forming lipid) membranes is examined. Large unilamellar vesicles were subjected to hypo-osmotic gradients and the leakage of their contents was quantified.

94-GHz spectra of lipid spin labels are sensitive to the rapid segmented motions of lipid chains even at the lower-end of high-frequency range. They allow a precise description of slow off-axial components of overall chain motion in combination with simulation of lower-frequency spectra.

The parameterization of a new coarse grained (CG) model for lipid and surfactant systems is presented. The results show the form of simulation should be used as much as possible to judge the quality of the CG force field in the application at hand.

The design, synthesis and characterization of cationic lipid formulations are explained. A description of the membrane forming characteristics is given.

The influence exerted on an integral membrane protein by its environment using the light-harvesting complex (LHI) of purple bacteria as a model, is studied. It is concluded that membrane environment significantly narrows the statistical distribution of conformational states available to the LH1 complex in comparison to the corresponding state distribution observed for the same detergent-solubilized protein.

It is observed the hydrophobic and electrostatic interactions with the membranes lipid play an important role as well as the RGD triplet located within the (110-121) linear hepatitis A virus (HAV) epitope, which belongs to the HAV-VP3 structural protein. The main aim is to test the effect on the membrane-peptide interaction of the replacement of the RGD tripeptide by RGE ([GLU]114VP3110) or RKD ([Lys]113 VP3110) sequences.

The lateral diffusion in a model membrane consisting of phospholipid monolayers attached to a polymer cushion is examined by means of fluorescence recovery after pattern photobleaching (FRAP). By TIR-FRAP pattern bleaching, ultraslow diffusion coefficients on the order of 10(super -12) cm(super 2)/s could be determined not only by order of magnitude but also with a precision of 10%.

The photophysical and diffusive behaviors of the dicyanomethylenedihydrofuran (DCDHF) lipid analogues in membranes are described and are found to be competitive with the well-known lipid probe. It is concluded that several members of a new class of single-molecule emitters could serve as useful lipid analogues in the plasma membrane of Chinese hamster ovary (CHO) cells, with sufficient brightness and stability to allow tracking of single-molecule diffusion.

Atomic force microscopy studies of the physical parameters determining the strength of lipid anchorage in bilayers as a function of the phase state of the lipid matrix are reported. Analysis of the data using both dynamic force spectroscopy and full microscopic models show that the anchorage strength is greater in gel-phase relative to fluid-phase lipids.

The organization properties of fluorescent DNA-lipids, either alone in water or in interaction with 1-octyl-beta-D-glucopyranoside micelles or eggs phosphatidycholine vesicles are examined. The result reveals that lipophilic chins of DNA-lipids on the melting behavior of the double stranded hybrids in water melting curves are broadened whereas in amphiphillic assembliesE duplexes melt as the unconjugated controls.

The oxygen permeation resistance of highly condensed monolayers composed of a homologous series of saturated diacyl phosphatidylcholine lipids was measured using a novel technique that combined micromanipulation and electrochemical techniques. The use of lipid monolayer-coated air microbubbles allowed measurement of the oxygen permeation resistance of fully condensed lipid monolayers that were previously unavailable using classical film balance techniques.

The fluorescence recovery after photobleaching (FRAP) is used to investigate the influence of solvents on the stability and mobility of polyelectrolyte multilayer (PEM)-supported lipid layers. The conclusions on charged polymeric systems complement investigations of uncharged polymer-supported model membranes and demonstrate the significance of local electrostatic interactions for issues of stability and dynamics.

The study reveals that solvation dynamics of a probe C480 in DMPC lipid vesicles in bulk water is different from the DMPC entrapper IEOS sol-gel matrix. This clearly indicates that the probe molecule is mobile in the DMPC entrapper sol-gel matrix.

The study is conducted to investigate the application of time domain dielectric spectroscopy (TDDS) from 500kHz to 3 GHz to the bR containing purple membrane film. It is concluded that the bR membrane, prepared like oriented and nonoriented films, demonstrate different temperature dependencies.

The validity of the model for Langmuir monolayers systems examining pure lipid-air-water systems for two motivated situation is explored. It is suggested that computer simulations of Langmuir monolayers must balance the level of detail describing the hydrogen-bonding and phospholipid headgroup electrostatic network the air/water interface with the desired time and spatial scales.

Three methods are used to investigate the thermodynamic and structural properties of the lipid A system. The methods used are light scattering, osmotic pressure measurements and small angle X-ray scattering.

The close coupling of heat capacity and adiabatic compressibility for various binary lipid system is demonstrated. The heat capacities with differential calorimetry and ultrasonic velocities with a sensitivity differential ultrasonic cell is measured and compared.

A series of multiple nanosecond molecular dynamics simulations is carried out for a dipalmitoylphosphatidycholine lipid bilayer system in water solution, with ubiquinone (UQ) freely moving inside the bilayer. The mobility and the preferential positions of the quinone molecule are studied.

A Brownian dynamics simulation of a saturated 16 C atom acyl chain, in an environment that reproduces a phospholipid bilayer in the gel phase, is presented. The simulations of t-PnA, a fluoresent fatty acid widely used to probe lateral lipid domains in bilayers and membranes, reinforces the validity of the mean-field description.