Controlled reduction of photobleaching in DNA origami - gold nanoparticle hybrids

JESICA PELLEGROTTI; GUILLERMO ACUÑA; ANASTASIYA PUCHKOVA; PHIL HOLZMEISTER; ANDREAS GIETL; BIRKA LALKENS; FERNANDO STEFANI; PHILIP TINNEFELD

NANO LETTERS (PRINT)

AMER CHEMICAL SOC

Lugar: Washington; Año: 2014 vol. 14 p. 2831 - 2836

1530-6984

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.