Supported phospholipid bilayers

Zhang, L., Longo, M. L. and Stroeve, P. (2000) Mobile Phospholipid Bilayers Supported on a Polyion/Alkyllhiol Layer Pair. Langmuir, 16, 5093—5099. ... 

In the bulk of this chapter we will focus on the rapidly emerging new in vitro technology based on the use of immobilized artificial membranes, constructed of phospholipid bilayers supported on lipophilic filters. One objective is to complete the coverage of the components of the transport model explored in Chapter 2, by considering the method for determining the top curve (horizontal fine) in the plots... 

N.G., and Fainstein, A. (2009) Phospholipid bilayers supported on thiolate-covered nanostructured gold in situ Raman spectroscopy and electrochemistry of redox species. ChemPhysChem, 10, 1927-1933. 

Cunin F, Milhiet PE, Anglin E, Sailor MJ, Espenel C, Le Grimellec C, Brunei D, Devoisselle JM (2007) Continuous planar phospholipid bilayer supported on porous silicon thin film reflector. Ultramicroscopy 107 1048... 

There has been a surge of research activity in the physical chemistry of membranes, bilayers, and vesicles. In addition to the fundamental interest in cell membranes and phospholipid bilayers, there is tremendous motivation for the design of supported membrane biosensors for medical and pharmaceutical applications (see the recent review by Sackmann [64]). This subject, in particular its biochemical aspects, is too vast for full development here we will only briefly discuss some of the more physical aspects of these systems. The reader is referred to the general references and some additional reviews [65-69]. 

Tamm, L. K. and McConnell, H. M. (1985) Supported phospholipid bilayers. Biophys. 

Membrane conformational changes are observed on exposure to anesthetics, further supporting the importance of physical interactions that lead to perturbation of membrane macromolecules. For example, exposure of membranes to clinically relevant concentrations of anesthetics causes membranes to expand beyond a critical volume (critical volume hypothesis) associated with normal cellular function. Additionally, membrane structure becomes disorganized, so that the insertion of anesthetic molecules into the lipid membrane causes an increase in the mobility of the fatty acid chains in the phospholipid bilayer (membrane fluidization theory) or prevent the interconversion of membrane lipids from a gel to a liquid form, a process that is assumed necessary for normal neuronal function (lateral phase separation hypothesis). 

These reconstitution experiments supported the model for electron transfer shown in figure 14.8. In this model the complexes do not bind to each other directly. Instead, movement of electrons from complexes I and II to complex III is mediated by diffusion of UQH2 from one complex to the other within the phospholipid bilayer. Similarly, electrons move from complex III to complex IV by the diffusion of reduced cytochrome c along the surface of the membrane. Remember that cytochrome c differs from the other cytochromes in being a water-soluble protein. It is attached loosely to the membrane surface by electrostatic interactions. 

Qeveral recent investigations using various physicochemical methods have provided convincing evidence to support the contention that the basic structure of most biological membranes consists of a phospholipid bilayer (1,2,3, 4). Studies on phospholipid model membranes can therefore be expected to yield relevant information on the role played by phospholipids in determining the characteristic properties of biological membranes (5). One important aspect of this problem concerns the mechanisms of interaction between the phospholipids and other membrane constituents such as cholesterol, proteins, and different inorganic... 

The Singer and Nicholson (13) model for the plasma membrane, which now receives much support, is basically a smectic liquid crystal consisting of one bilayer of phospholipid (Figure 4a). The phospholipid bilayer contains cholesterol at a concentration which depends on cell type. Embedded in the lipid liquid crystal he protein molecules. Some of these protein molecules transverse the entire lipid bilayer and communicate both with the inside and the outside of the cells. Some of these may... 

FIGURE 6.1. Schematic diagram of a supported phospholipid bilayer membrane containing a covalently attached ligand molecule. 

FIGURE 6.7. Epifluorescent images of (a) Texas Red labeled streptavidin confined in aqueous compartments above solid supported phospholipid bilayers containing 2 mol% biotinylated lipids. Each box contains a different aqueous phase small molecule as described in the text, (b) Same system as in (a), but fluorescence is excited by total internal reflection revealing that streptavidin is surface bound in boxes 1, 2, and 4, while the surface in box 3 remains protein free. 

T. Yang, E. E. Simanek, and P. S. Cremer, Creating addressable aqueous microcompartments above solid supported phospholipid bilayers using lithographically patterned poly(dimethylsiloxane) molds, Anal. Chem. 72, 2587-2589 (2000). 

Reviakine I, Brisson A (2000) Formation of supported phospholipid bilayers from unilamellar vesicles investigated by atomic force microscopy. Langmuir 16 1806-1815... 

The use of solid-supported lipid membranes (SSLM) to measure membrane affinity was recently reported by Loidl-Stahlhofen (2001a, 2001b). To produce solid-supported lipid membranes a single phospholipid bilayer membrane is non covalently... 

Gagner, J., Johnson, H., Watkins, E., Li, Q., Terrones, M., and Majewski, J. (2006), Carbon nanotube supported single phospholipid bilayer, Langmuir, 22,10909-10911. 

As an intermediate between solid supported layers and the inherent dynamic and nanostructured properties of phospholipid vesicle supports, silica and especially mesoporous silica nanoparticles may provide interesting platforms for dynamic bilayers. Previous studies have shown that stable bilayers can form on both amorphous [102] or functional silica [103, 104] and mesoporous nanoparticles [105] or membranes [106]. This type of biomimetic carrier has great potential as a type of trackable stabilized membrane capable of displaying cellular targeting elements in a close to natural configuration. 

Glasmastar, K., Larsson, C., Hook, F., and Kasemo, B. (2002). Protein adsorption on supported phospholipid bilayers. J. Colloid Interface Sci., 246,40-47. 

Tamm LK. Lateral diffusion and fluorescence microscope studies on a monoclonal antibody specifically bound to supported phospholipid bilayers. Biochemistry 1988 27 1450-1457. 

Naumann CA, Prucker O, Lehmann T, Ruhe J, Knoll W, Frank CW. The polymer-supported phospholipid bilayer tethering as... 

Thid D, Hohn K, Eriksson PS, Ekeroth J, Kasemo B, Gold J. Supported phospholipid bilayers as a platform for neural progenitor cell culture. J. Biomed. Mater. Res. A. 2007. 

Phospholipids are known to be very difficult to transfer in more than one layer using the standard LB technique. A combination of vertical and horizontal dipping has been successfully applied to produce supported bilayers and multilayers with hydrophilic outer surfaces ). Alternatively, phospholipid bilayers on solid substrates can be created by vesicle adsorption ). One of the issues is whether they remain intact. 

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