Single fluorophores can be localized with nanometer precision using FIONA. Here a summary of the FIONA technique is reported, and how to carry out FIONA experiments is described.
Wang, Y., Cai, E., Sheung, J., Lee, S. H., Teng, K. W., Selvin, P. R. Fluorescence Imaging with One-nanometer Accuracy (FIONA). J. Vis. Exp. (91), e51774, doi:10.3791/51774 (2014).