Surface Engineering

Suspended Lipid Bilayers on Porous Supports

Processes at lipid bilayer membranes, e.g. binding of proteins or peptides and the function of membrane proteins are essential for the functioning of every cell. However, systematic investigations on whole cells are relatively complicated. Therefore, model systems have been developed.

Supported membranes have been used to study a wide variety of membrane proteins. They provide an ideal experimental platform to study biorecognition processes in a quasi-natural environment. However, often access to both sides of the lipid bilayer is required.

We therefore develop a system, where a lipid bilayer is spanned over a porous substrate, e.g. porous alumina or porous silicon. In contrast to classical bilayer lipid membranes, the porous substrate offers and enhanced stability by supporting or anchoring the bilayer on the rim of the pores. At the same time, the pores provide a free volume underneath the bilayer, allowing access to both leaflets of the bilayer and providing space for extramembrane domains of transmembrane proteins. These porous materials have tunable thickness and pore diameters ranging from 20 - 100 nm and high surface area are chemically inert in aqueous medium, biocompatible and allow for chemical surface modifications.

We incorporate membrane proteins into these suspended bilayers and investigate protein function.

 

Figure 10. Schematic representative of lipid bilayers suspended on porous materials.