ABSTRACT
Fluorescence microscopy has become one of the most prominent and versatile research tools used in modern cell biology and in principle ideal to investigate cell membrane organization in living cells. The most commonly used near-field scanning optical microscopy (NSOM) configuration for biological applications is based on aperture-type fibre probes as described earlier, although other types of approaches have also been implemented. The most crucial component of aperture-type NSOM is the fabrication of the actual probe. To date, the most commonly employed NSOM configuration relies on shear-force feedback based on the use of quartz tuning forks. The use of NSOM to investigate monolayers has also been extended towards bilayers and protein containing lipid layers in dry or buffer conditions. In contrast, NSOM guarantees a perfect overlay between multiple excitation wavelengths, an essential requirement to resolve the true nanoscale landscape of cell membranes.
