M. Balon et al., A fluorescence study of the molecular interactions of harmane with the nucleobases, their nucleosides and mononucleotides, BIOPHYS CH, 80(1), 1999, pp. 41-52
Fluorescence binding studies of harmane to the elemental components of the
nucleic acids were undertaken to investigate the origin of the interaction
between the drug and DNA. Most of the tested substrates have been found to
induce hypochromism in the absorption spectrum of harmane and to quench its
fluorescence. The quenching process induced by the nucleobases and their n
ucleosides is mainly due to the formation of ground state 1:1 complexes. Ho
wever, in the case of the mononucleotides a dynamic quenching component is
also observed. This quenching component is likely due to the excited state
interaction of harmane with the phosphate group of the nucleotides. UV-vis
spectral changes and quenching measurements have been used to quantify the
ground state association constants of the complexes and the quenching rate
constants. (C) 1999 Elsevier Science B.V. All rights reserved.