Premium
Long‐Lived Excited‐State Dynamics of i‐Motif Structures Probed by Time‐Resolved Infrared Spectroscopy
Author(s) -
Keane Páraic M.,
Baptista Frederico R.,
Gurung Sarah P.,
Devereux Stephen J.,
Sazanovich Igor V.,
Towrie Michael,
Brazier John A.,
Cardin Christine J.,
Kelly John M.,
Quinn Susan J.
Publication year - 2016
Publication title -
chemphyschem
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.016
H-Index - 140
eISSN - 1439-7641
pISSN - 1439-4235
DOI - 10.1002/cphc.201501183
Subject(s) - excited state , nucleobase , chemistry , spectroscopy , stacking , infrared , infrared spectroscopy , photochemistry , excitation , atomic physics , dna , optics , physics , biochemistry , organic chemistry , quantum mechanics
UV‐generated excited states of cytosine (C) nucleobases are precursors to mutagenic photoproduct formation. The i‐motif formed from C‐rich sequences is known to exhibit high yields of long‐lived excited states following UV absorption. Here the excited states of several i‐motif structures have been characterized following 267 nm laser excitation using time‐resolved infrared spectroscopy (TRIR). All structures possess a long‐lived excited state of ∼300 ps and notably in some cases decays greater than 1 ns are observed. These unusually long‐lived lifetimes are attributed to the interdigitated DNA structure which prevents direct base stacking overlap.