Liposome Electroformation

Angelova, Miglena, I., Liposome Electroformation, 6, 27 see also Kinnunen, Paavo, K., 6, 273. 

Angelova ML, Dimitrov DS. Liposome electroformation. Farady 42. Disc. Chem. Soc. 1986 81 303-311. 

Angelova Ml, Dimitrov DS (1986) Liposome electroformation. Faraday Discuss 81 303-311... 

Liposome electroformation protocols have the following steps (i) depositing a dry lipid film on the electrode surface (ii) application of the external electric field and filling the working chamber with water or aqueous solution (iii) guiding vesicle... 

It should be noted that the level of speculation increases down the list. The exact mechanisms of liposome electroformation are still not entirely understood. 

One reason to develop liposome electroformation was to establish a method for tire preparation of unilamellar cell-sized vesicles of a particular lipid composition, and thereby imitate biological cells with respect to their mechanical and electric properties. This could then be used for the direct optical microscopy model study of membrane interactions. 

The first application of liposome electroformation was in supplying the starting objects (isolated unilamellar vesicles of a particular lipid composition, size and membrane tension) for membrane bending elasticity measurements by image analysis of membrane thermal fluctuations [14,15,23,27], See also Chapter 14 of this book. 

Unfortunately, there are only few data available describing the effects of ethanol on conventional liposomes composed of molecules with mixed-chain fatty acids, such as POPC. The few permeability studies seem to demonstrate that the effect of ethanol on such liposomes might be low. And with GVs, there is (to the best of my knowledge) only one study that has been published demonstrating the effect of ethanol on the GV bilayers. In this study it was shown that high concentrations of ethanol induce shape transformations of GV formed by electroformation and it was assumed that the stability of these GVs might be negatively influenced. 

Besides simply pouring water over the film, the vesicles can also be produced using an external stimulus like a constantly changing electrical field. This method is called electroformation and is widely used for liposome production. Upon a change in the frequency of the changing electrical field applied, the vesicles eventually detach from the surface, yielding giant polymersomes of several micrometers in diameter. 

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