A method of determining donor-acceptor distribution functions in Forster resonance energy transfer

We describe a method of determining the distribution function associated wi th accepters partaking in Forster resonance energy transfer (FRET) from exc ited donors. Unlike previous approaches to this problem the method describe d makes no a priori assumption about the nature of the distribution. The us e of an acceptor distribution function in analyte sensing is demonstrated f or the first time. In the case of glucose sensing via FRET from Concanavali n A labelled with allophycocyanin to malachite green labelled dextran, the change in the acceptor distribution is shown to be a more sensitive sensing parameter than either the mean fluorescence lifetime or Forster gamma valu e. (C) 2000 Elsevier Science B.V. All rights reserved.