Fluorescence nanotomography: a structural tool in biomedical sensing

Fluorescence nanotomography (FN) is a newly developed method for determining molecular distributions on a nanometre scale in soft solids, biological macromolecules and medically important systems. FN uses fluorescence resonance energy transfer (FRET) for the recognition of the separations between molecules. By using a fluorescence lifetime measurement of sub-nanosecond time resolution, the spatial resolution of the resulting distribution function can be better than 1 �. In this paper the theoretical background of the method is outlined and the results of simulations on model molecular distributions presented. This is followed by demonstration of several applications of FN to real molecular systems, including bulk solutions of molecules of different sizes, complexes, porous polymers, phospholipids and sugar-protein competitive binding sensors glucose. The experimental requirements of FN as a structural tool for wide class of biomedical systems are discussed.