Phosphatidylcholine monolayers

McConnell et al. [196] and Andelman and co-workers have predicted [197,198] an ordered array of liquid domains in the gas-liquid coexistence regime caused by the dipole moment difference between the phases. These superstructures were observed in monolayers of dipalmitoyl phosphatidylcholine monolayers [170]. 

I. Vikholm, W.M. Albers, H. Valimaki, and H. Helle, In situ quartz crystal microbalance monitoring of Fab-fragment binding to hnker lipids in a phosphatidylcholine monolayer matrix application to immunosensors. Thin Solid Films 327, 643-646 (1998). 

F. Gerber, M.P. Krafft, T.F. Vandamme, M. Goldman, P. Fontaine, Fluidization of a dipalmitoyl phosphatidylcholine monolayer by fluorocarbon gases Potential use in lung surfactant therapy, Biophys. J. 90 (2006) 3184-3192. 

Griffin, M.C.A., Infante, R.B., Klein, R.A. 1984. Structural domaines of K-casein show different interaction with dimyristoyl phosphatidylcholine monolayers. Chem. Phys. Lips. 36, 91-98. 

It should be pointed out that the NBF equivalent thickness hw is 7.6 nm while after Cei,cr, hw = 8.1 nm. The small difference in NBF thickness cannot be treated quantitatively but is an indications that there is no free aqueous core in the NBF. Assuming the three-layer film structure, refraction coefficient of tetradecane ri = 1.43, and, refraction coefficient of water, m = 1.33, on the basis of X-ray diffraction, neutron scattering and NMR data [289], we obtain hi = 1.6 nm. Hence, h2 = 3.8 nm and the total film thickness h2 + 2h equals 7.0 nm. This value is close to the results obtained by a completely different method for the thickness of two hydrated dipalmitoyl phosphatidylcholine monolayers - 6.8 nm, reported by Marra [290]. 

D.W. Grainger, A. Reichert, H. Rings-DORE, and C. Salesse. An enzyme caught in action direct imaging of hydrolytic function and domain formation of phospholipase A.2 in phosphatidylcholine monolayers. FEBS Lett., 1989, 252, 71-82. 

The decrease in the dipole potential is correlated with the amount of water per lipid displaced by phloretin molecules (Table 34.2). As shown in Figure 34.2, a 20% phloretin decreases by 180 mV the dipole potential in phosphatidylcholine monolayers, with the displacement of around 40% of the water hydrating the phospholipids. As phloretin does not interact with the carbonyls (Figure 34.1), the decrease of dipole potential may be ascribed to the elimination of polarized water from the P = O group (Diaz et al., 2001). This action is not observed in DMPE monolayers, whose phosphate group is hydrogen bounded to the amine group (Lairion and Disalvo, 2004). 

Diaz, S., Lairion, R, Arroyo, J., Biondi de Lopez, A.C., and Disalvo, E.A. Contribution of phosphate groups to the dipole potential of dimiristoyl phosphatidylcholine monolayers, Langmuir, 17, 852, 2001. 

Stillwell W, Ehringer WD, Dumaual AC, Wassail SR. Cholesterol condensation of alpha-linolenic and gamma-linolenic acid-containing phosphatidylcholine monolayers and bilayers. Biochim Biophys Acta 1994 1214 131-136. 

Kalduchi, T., M. Nakanishi, and M. Senda (1989). The electrocapillary curves of the phosphatidylcholine monolayer at the polarized oil-water interface. II. Double layer structure of dilauroylphosphatidylcholine monolayer at the nitrobenzene-water interface. Bull. Chem. Soc. Jpn 62, 403-409. 

Worthman LAD, Nag K, Davis PJ, Keough KMW (1997) Cholesterol in condensed and fluid phosphatidylcholine monolayers studied by epifluorescence microscopy. Biophys J 72 2569-2580... 

Sakurai, I., and Kawamura, Y. 1987. Lateral electrical conduction along a phosphatidylcholine monolayer. 405 09. 

Samec, Z., A. Trojanek, and H. H. Girault, Thermodynamic analysis of the cation binding to a phosphatidylcholine monolayer at a polarised interface between two immiscible electrolyte solutions, Electrochem Commun, Vol. 5, (2003) p. 98. 

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