Detection of nucleic acid hybridization via fluorescence resonance energy transfer (FRET) using pyren-1-ylmethyl and perylen-3-ylmethyl N2′-functionalized 2′-amino-LNA nucleosides incorporated into oligonucleotides exhibited a clear distance dependence of the FRET efficiency, ranging from below 10% when the fluorophores were approximately 40 Å apart to approximately 90% when the fluorophores were in close proximity. © 2007 Elsevier Ltd. All rights reserved.