Surface plasmon resonance as detection tool for lipids lateral mobility in biomimetic membranes.

A procedure based on surface plasmon resonance (SPR) is proposed to monitor the lateral mobility of lipid molecules in solid-supported bilayer lipid membranes (ssBLMs), an essential prerequisite for the formation of important microdomains called lipid rafts (LRs). The procedure relies on the marked tendency of the ganglioside GM1 to be recruited by LRs and to act as a specific receptor of the beta-subunit of the cholera toxin (ChTB). In the presence of both GM1 and ChTB, spontaneous formation of lipid rafts domains in mobile ssBLMs is accompanied by an appreciable increase in the amount of adsorbed ChTB, as monitored by SPR.