Headgroups structures

For pure phosphatidylcholine bilayers, the orientation of the headgroup has been well characterized showing that headgroups are aligned approximately parallel to the bilayer surface. Because only one phosphorus with 100% natural abundance is contained in the phospholipid molecule, NMR has become an important tool to study the phospholipid headgroup structure and dynamics. ... 

Well-expressed correlations between headgroup structure and transfection activity have been found for cholesterol-based cationic derivatives. Polyamine derivatives with T-shaped structure exhibit considerably higher levels of transfection as compared to lipids with linear polyamine headgroups (Fig. 6) [36]. Varying... 

Polar Headgroup Structure Influence on CMC and Headgroup Area A for a Series of Dodecyl Surfactants (Excerpted from Rosen, 1989). The Solvent is Distilled Water. 

Another class of phospholipids is the sphingofipids. A sphingofipid molecule has the phosphatidyl-based headgroup structure described above, but (in contrast to a common phospholipid molecule) contains a single fatty acid... 

Murzyn K, Zhao W, Karttunen M, Kurdziel M, Rog T (2006) Dynamics of water at membrane surfaces effect of headgroup structure. Biointerphases 1 98... 

Heinz, H., Vaia, R. A., Rrishnamoorti, R., and Farmer, B. L. 2007. Self-assembly of alkylam-monium chains on montmorillonite Effect of chain length, headgroup structure, and cation exchange capacity. Chemistry cf Materials 19 59-68. 

We are interested in the construction of nanomeric structures based on mixed amphiphilic biocomponents for which the mixing behavior from almost ideal mixing to complete immiscibility would strongly depend on hydrocarbon chain interaction between two components and the differences in their headgroup structure [8]. 

The cmc values of pure surfactants are sensitive to the structure of the surfactant, that is, the nature of the alkyl tail, headgroup structure, and counterion type, the composition of the solution, and to changes in temperature. One commonly observed correlation is the linear relationship between the between log cmc and the number of carbons, n, in the surfactant tail ... 

The decanoyl derivative forms micelles up to around 15 wt % surfactant, while the stearoyl and oleyl only form micelles at less than 2 wt % surfactant. In addition, the decanoyl derivative displays a significantly depressed Krafft temperature boundary, around 30°C compared to more than 40°C for the other two. The micelles formed by the decanoyl derivative were shown by NMR to be spherical in the dilute region but become more disk-shaped as the phase boundary is approached. This work provides data that complements that of Soderberg et al. [27] in that it examines the systematic change in hydrophobe rather than the systematic change in headgroup structure as performed by Soderberg et al. 

Megha, Sawatzki P, Kolter T, Bittman R, London E. Effect of ceramide N-acyl chain and polar headgroup structure on the properties of ordered Upid domains (Upid rafts). Biochim Biophys Acta. 2007 1768(9) 2205-2212. 

Seelig, I. (1978). P nuclear magnetic resonance and the headgroup structure of phospholipids in membranes, Biochim. Biophys. Acta 515,105-140. 

We have systematically investigated various mixtures of phospholipids differing in headgroup structure and chain length. The details of these investigations are found in the relevant publications [80,85-87,90]. 

Okano, L.T., Quina, F.H., El Seoud, O.A. Fluorescence and light-scattering studies of the aggregation of cationic surfactants in aqueous solution effects of headgroup structure. Langmuir 2d(i0, 76(7), 3119-3123. 

Bunton, C.A., Poroudian, H.J., GiUitt, N.D. Effects of headgroup structure on dephosphorylation of p-nitrophenyl diphenyl phosphate by functional oximate comiceUes. Langmuir 1999, 75(4), 1067—1074. 

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