on-line protocol: Bio-protocol: http://www.bio-protocol.org/wenzhang.aspx?id=854The arrangement in eukaryotic cell membranes of liquid-ordered states surrounded by liquid-disordered phases allows for the existence of organized membrane microdomains called rafts. Rafts play a crusial role in signal-transduction events, in lipid transport and in various internalization processes, and for all these reasons need to be purified for further characterization