On the Feasibility of Single Molecule Detection of the Guanosine-Analogue, 3-MI

Published

September 1, 2004

Author(s)

J E. Sanabia, Lori S. Goldner, P A. Lacaze, M E. Hawkins

Abstract

We present UV fluorescence fluctuation correlation spectroscopy (FCS) measurements on the guanosine-analog 3-MI [3-Methyl-8-(2-deoxy- -D-ribofuranosyl)isoxanthopterin], a pteridine widely used in studies of DNA binding and dynamics. We measure the photon count rate and signal-to-background per molecule, for both monomeric 3-MI and a 3-MI-containing oligonucleotide. For the monomer, we find a photon count rate per molecule above 4 kHz and a signal to background ratio of 5. For incorporated 3-MI, both parameters are a factor of 4 smaller. We discuss triplet and photobleaching behavior of 3-MI and the possibilities of using this analog in single molecule studies of DNA dynamics. Comparisons are made to the behavior of stilbene 3, a brilliant laser dye.

Citation

Journal of Physical Chemistry Part B Condensed Matter, Materials, Surfaces, Interfaces & Biophysical

Volume

108

Issue

No. 39

Pub Type

Journals

Keywords

), nucleic acid analog, FCS, fluorescence correlation spectroscopy, photostability, single molecule microscopy

Citation

Sanabia, J. , Goldner, L. , Lacaze, P. and Hawkins, M. (2004), On the Feasibility of Single Molecule Detection of the Guanosine-Analogue, 3-MI, Journal of Physical Chemistry Part B Condensed Matter, Materials, Surfaces, Interfaces & Biophysical (Accessed October 15, 2025)