Intermolecular energy transfer between appropriately chosen pairs of dyes can be used to induce or enhance banding patterns in human metaphase chromosomes. Intermolecular transfer of electronic excitation energy, which depends on the inverse sixth power of the separation between donor and acceptor dyes (1), has been extensively used to examine proximity relationships in well-defined biochemical systems (2)(3)(4)(5) Values for R0, the critical distance for 50% efficient energy transfer between different dye pairs, were calculated from the * To whom reprint requests should be sent.
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