Axial nanoscale localization by normalized total internal reflection fluorescence microscopy.

We present a simple modification of a standard total internal reflection fluorescence microscope to achieve nanometric axial resolution, typically ≈10  nm. The technique is based on a normalization of total internal reflection images by conventional epi-illumination images. We demonstrate the potential of our method to study the adhesion of phopholipid giant unilamellar vesicles.