Comparison of the photoluminescence properties of semiconductor quantum dots and non-blinking diamond nanoparticles. Observation of the diffusion of diamond nanoparticles in living cells

TL;DR

This paper compares the photoluminescence properties of semiconductor quantum dots and nanodiamonds, highlighting nanodiamonds' superior photostability and their application in tracking nanoparticles in living cells.

Contribution

It introduces nanodiamonds with photoluminescent centers as a stable alternative to quantum dots and demonstrates their use in live cell imaging.

Findings

Nanodiamonds exhibit no photoblinking and high photostability.

Photoluminescence intensity of nanodiamonds is comparable to quantum dots.

Successful tracking of nanodiamonds in living cells.

Abstract

Long-term observations of photoluminescence at the single-molecule level were until recently very diffcult, due to the photobleaching of organic ?uorophore molecules. Although inorganic semiconductor nanocrystals can overcome this diffculty showing very low photobleaching yield, they suffer from photoblinking. A new marker has been recently introduced, relying on diamond nanoparticles containing photoluminescent color centers. In this work we compare the photoluminescence of single quantum dots (QDs) to the one of nanodiamonds containing a single-color center. Contrary to other markers, photoluminescent nanodiamonds present a perfect photostability and no photoblinking. At saturation of their excitation, nanodiamonds photoluminescence intensity is only three times smaller than the one of QDs. Moreover, the bright and stable photoluminescence of nanodiamonds allows wide field observations of single nanoparticles motion. We demonstrate the possibility of recording the tra jectory of such single particle in culture cells.