protocol for liposome preparation

[Dr Engelbert Buxbaum]

Am 29.11.2008, 14:16 Uhr, schrieb michael nelson <gnomenm from yahoo.com>:


> I have some difficulties preparing for clear liposomes solutions. Here  
> is what I did, please advise.
>
>  I start off with 0.1g/ml phosphatidylcholine chloroform solution. I  
> then move it into a round bottomed flask and dry it in a rotary  
> evaporator. However, instead of getting thin films on the surface, what  
> I end up with is a large chunk of light yellowish solid. Does that mean  
> I have to use a larger volume of organic solvent?
>
> I then dissolve them into buffer and sonicate. Finally, I got some milky  
> suspension. I assume they are multimellar vesicles. My advisor told me  
> that I could sonicate to make them unilamellar and make the solution  
> goes clear. I tried, but didn't work.

There is the classical method of pressing these multilamellar vesicles  
through a narrow-pore membrane. However, more consistent results you will  
obtain by dissolving the lipids with detergents as mixed micelles and then  
striping the detergent away with polystyrene beads (e.g. Biobeads SM2).  
Rigaud's group has done extensive work on this, check their papers.