Mobile lipid bilayers on gold surfaces through structure-induced lipid vesicle rupture

Area of Science:

• Biophysics
• Materials Science
• Surface Chemistry

Background:

• Fluid supported lipid bilayers (SLBs) are crucial for studying membrane-associated biomolecular interactions using techniques like surface plasmon resonance.
• Forming fluid SLBs on gold surfaces via lipid vesicle deposition remains a significant challenge in lipid bilayer research.

Purpose of the Study:

• To develop a method for forming mobile supported lipid bilayers (SLBs) on gold surfaces.
• To investigate the role of nanostructure geometry in inducing lipid vesicle rupture and SLB formation.

Main Methods:

• Fabrication of nanograting structures on gold surfaces.
• Lipid vesicle deposition onto nanograted and planar gold surfaces.
• Fluorescence recovery after photobleaching (FRAP) to assess SLB fluidity and formation.
• Analysis of fluorescence intensity recovery patterns and coverage fractions.

Main Results:

• Nanograting structures induced lipid vesicle rupture, forming mobile SLBs with measurable fluidity.
• A second layer of SLB partially formed on top of the first, particularly along grating edges.
• The extent of second SLB formation correlated directly with grating edge density.
• SLBs on planar supports exhibited no fluidity, unlike those on nanograted surfaces.

Conclusions:

• Grating edges act as effective sites for inducing vesicle rupture and forming mobile second SLBs on gold.
• The ability to control second SLB formation at specific edge locations allows for patterning of mobile lipid bilayers.
• This approach offers a novel method for creating patterned, fluid lipid bilayers for advanced biomolecular studies.