Scanning Force Microscopy of Artificial Membranes

Visualization of biological membranes by scanning force microscopy (SFM) has tremendously improved the current understanding of protein–lipid interactions under physiological conditions. SFM is the only tool to directly image processes on surfaces in aqueous solution at molecular resolution. Besides being a supportive means to confirm results on lipid phases and domains obtained from fluorescence spectroscopy, calorimetry, and X‐ray crystallography, SFM has contributed distinct aspects on the formation of 2D crystals of various membrane‐confined proteins and morphological changes of membranes due to the interaction of peptides and proteins. This review will focus on recent results in SFM imaging of artificial solid‐supported membranes, their phase behavior as a response to the environment, and changes in membrane morphology induced by the partitioning of peptides and proteins. Providing both high lateral and vertical resolution, in situ scanning force microscopy of biological membranes immobilized on a solid support is a means to obtain images of bilayers and membrane‐confined peptides and proteins (see schematic representation). In addition to visualizing surface topography, material contrast unravels membrane organization and dynamics as well as peptide–membrane interactions on the nanometer scale.