DNAs, RNAs, and other polymer folding dynamics have been measured using FRET. Usually, these systems are under equilibrium whose kinetics is hidden. However, they can be measured by measuring single-molecule FRET with proper placement of the acceptor and donor dyes on the molecules. See single-molecule FRET for a more detailed description. Other applications In addition to common uses previously mentioned, FRET and BRET are also effective in the study of biochemical reaction kinetics. FRET is increasingly used for monitoring pH dependent assembly and disassembly and is valuable in the analysis of nucleic acids encapsulation. This technique can be used to determine factors affecting various types of nanoparticle formation as well as the mechanisms and effects of nanomedicines. Other methods A different, but related, mechanism is Dexter electron transfer. An alternative method to detecting protein–protein proximity is the bimolecular fluorescence complementation (BiFC), where two parts of a fluorescent protein are each fused to other proteins. When these two parts meet, they form a fluorophore on a timescale of minutes or hours. See also Dexter electron transfer Förster coupling Surface energy transfer Time-resolved fluorescence energy transfer References External links FRET Imaging (Tutorial of Becker & Hickl, website) Imaging Fluorescence Biochemistry methods Biophysics Cell imaging Optical phenomena Protein–protein interaction assays Fluorescence techniques Cell biology Laboratory techniques Molecular biology techniques Energy transfer