The phase behaviour and surface structure of dipalmitoyl phosphatidyl choline (DPPC) monolayers at the air/water interface, in the absence and the presence of procaine, have been investigated by LangmuirBlodgett (LB) technique and atomic force microscopy. The LB films were transferred on mica, at a controlled surface pressure, characteristic for the expanded liquid to condensed liquid phase tra...

Fluoroquinolones antibiotics are effective intracellular antibiotics, and their activity depends on achieving appropriated concentrations. It is thought that to reach the intracellular environment, fluoroquinolones interacts with the membranes lipid bilayer and/or recognizes the membranous proteins like efflux pumps (1,2). Therefore, probing drug/lipid interactions at the molecular level repres...

Aim. To substantiate the optimal technology for obtaining two types of bio-related liposomes based on composition dipalmitoyl-L-α phosphatidylcholine (DPPC) or palmitoyl-sphingomyelin-N-hesadecanoyl-D erythrosphingosylphosphorylcholine (C16-SM) with cholesterol and study their interaction a fluorophore-containing compound. Materials methods. prepare liposomal vesicles phospholipids – DPPC, C16-...

The mechanism of action of bovine milk lipoprotein lipase (LpL) was studied with a water-soluble substrate of p-nitrophenylbutyrate (PNPB). The calculated maximal velocity ( Vmm) and Michaelis constant (Km) values at 37 "C were 2.0 pmol of p-nitrophenol released/min/ mg of LpL and 0.52 mM, respectively. The addition of phospholipid vesicles enhanced the rate of PNPB hydrolysis by LpL. In the pr...

The -amyloid peptide (A ) (1–40) is one of the major components that form Alzheimer’s amyloid deposits. Studies of the membrane insertion of amyloid showed that amyloid is surface active and can insert into lipid monolayers [Ji et al. (2002). Biochemistry (Moscow), 67, 1283–1288; Ege & Lee (2004). Biophys. J. 87, 1732–1740]. The interaction between the peptide and a lipid monolayer or bilayer i...

We present a highly sensitive nuclear-magnetic resonance technique to study membrane dynamics that combines the temporary encapsulation of spin-hyperpolarized xenon ((129)Xe) atoms in cryptophane-A-monoacid (CrAma) and their indirect detection through chemical exchange saturation transfer. Radiofrequency-labeled Xe@CrAma complexes exhibit characteristic differences in chemical exchange saturati...

Zeta potential, effective diameter and sedimentation rate of TiO2 (Degussa P-25) suspension were studied in the presence of NaCl and anionic (sodium dodecyl sulfate, SDS) or cationic (dodecyltrimethylammonium bromide, DTAB; tetradecyltrimethylammonium bromide, TTAB; and hexadecyltrimethylammonium bromide, CTAB) surfactant, as well as lecithin (1,2-dipalmitoyl-sn-glycero-3-phosphocholine, DPPC)....

The influence of hormones in water subphase on the stability of monolayers built of phospholipid mixtures extracted from embryogenic (PLE) and nonembryogenic (PLNE) wheat calli was examined. Additionally, experiments on individual lipids, dipalmitoylphosphatidylcholine (DPPC) and dipalmitoylphosphatidic acid (DPPA), were performed. DPPC was chosen because it was the main phospholipid present in...

A molecular model is proposed of a bilayer consisting of fully saturated dipalmitoylphosphatidylcholine (DPPC) and mono-unsaturated dioleoylphosphatidylcholine (DOPC). The model not only encompasses the constant density within the hydrophobic core of the bilayer, but also the tendency of chain segments to align. It is solved within self-consistent field theory. A model bilayer of DPPC undergoes...