- Main
Single-Molecule Detection of a Fluorescent Nucleobase Analogue via Multiphoton Excitation
Published Web Location
https://doi.org/10.1021/acs.jpclett.9b02108Abstract
The ability to routinely detect fluorescent nucleobase analogues at the single-molecule level would create a wealth of opportunities to study nucleic acids. We report the multiphoton-induced fluorescence and single-molecule detection of a dimethylamine-substituted extended-6-aza-uridine (DMAthaU). We show that DMAthaU can exist in a highly fluorescent form, emitting strongly in the visible region (470-560 nm). Using pulse-shaped broadband Ti:sapphire laser excitation, DMAthaU undergoes two-photon (2P) absorption at low excitation powers, switching to three-photon (3P) absorption at high incident intensity. The assignment of a 3P process is supported by cubic response calculations. Under both 2P and 3P excitation, the single-molecule brightness was over an order of magnitude higher than reported previously for any fluorescent base analogue, which facilitated the first single-molecule detection of an emissive nucleoside with multiphoton excitation.
Many UC-authored scholarly publications are freely available on this site because of the UC's open access policies. Let us know how this access is important for you.
Main Content
Enter the password to open this PDF file:
-
-
-
-
-
-
-
-
-
-
-
-
-
-