Chemical nanoscopy of cell-like membranes

摘要

We have set-up a scanning near-field infrared microscope (SNIM) with widely tunable lasers for label-free molecule identification by infrared spectral fingerprints. The lateral resolution is as low as 30 nm corresponding to the nanotip curvature radius. We obtained infrared spectra from nanoscale sections of self-assembled monolayers (SAM) with volumes as small as 0.01 attoliter corresponding to less than 30000 molecules. Spectroscopy of lipid bilayer stacks on mica revealed nanoscale near-field depth resolution of 80 to 120 nm. We discuss combined systems of membrane proteins and lipids on SAM supports approaching cell like membrane structures. We report on the progress of the set-up of an infrared and terahertz near-field microscope for the new synchrotron beam line at ANKA for full spectral nanoscale information retrieval.