Testing Membrane Interactions of CPPs
The chapter deals with some biophysical methods used for investigating CPP-induced changes in membrane properties by spectroscopy methods such as fluorescence or NMR and methods used for probing CPP-induced leakage in membranes. Some useful model systems for biomembranes are described. These include large unilamellar phospholipid vesicles (LUVs) of well-defined size (diameter typically 100 nm). A protocol for the preparation of such vesicles is included. The leakage studies make use of LUVs with entrapped dye molecules. The NMR studies make use of mixed micelles (bicelles) as a membrane mimetic system, which can be oriented in the magnetic field of the spectrometer.
Key wordsFluorescence NMR Large unilamellar vesicles Bicelles Membrane leakage Membrane fluidity Membrane dynamics
The work presented in this article was supported by grants from the Swedish Research Council, the Center for Biomembrane Research, and from the Knut and Alice Wallenberg Foundation. We thank Dr. Jesper Lind for assistance in producing the figure.
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