Controlled reduction of photobleaching in DNA origami-gold nanoparticle hybrids

Nano Lett. 2014 May 14;14(5):2831-6. doi: 10.1021/nl500841n. Epub 2014 Apr 4.

Abstract

The amount of information obtainable from a fluorescence-based measurement is limited by photobleaching: Irreversible photochemical reactions either render the molecules nonfluorescent or shift their absorption and/or emission spectra outside the working range. Photobleaching is evidenced as a decrease of fluorescence intensity with time, or in the case of single molecule measurements, as an abrupt, single-step interruption of the fluorescence emission that determines the end of the experiment. Reducing photobleaching is central for improving fluorescence (functional) imaging, single molecule tracking, and fluorescence-based biosensors and assays. In this single molecule study, we use DNA self-assembly to produce hybrid nanostructures containing individual fluorophores and gold nanoparticles at a controlled separation distance of 8.5 nm. By changing the nanoparticles' size we are able to systematically increase the mean number of photons emitted by the fluorophores before photobleaching.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Biosensing Techniques*
  • DNA / chemistry
  • Gold / chemistry*
  • Metal Nanoparticles / chemistry*
  • Photobleaching*
  • Photons

Substances

  • Gold
  • DNA