Time-gated detection of near-infrared emitting quantum dots for in vivo cell tracking

Abstract : In vivo cell tracking is a promising tool to improve our understanding of certain biological processes (circulating tumour cells migration, immune cells activity). Fluorescence microscopy ensures a high resolution and a good sensitivity. The latter is however limited by the high tissue autofluorescence and poor visible light penetration depth.We present the synthesis and characterization of Zn-Cu-In-Se / ZnS (core/shell) QDs made of low toxicity materials. These QDs exhibit a bright emission centered around 800 nm, where absorption and scattering of tissues are minimal. These nanocrystals are coated with a new surface chemistry, which yields small and bright probes in the cell cytoplasm for several days after labelling.These QDs also present a fluorescence lifetime much longer (150 ns) than the tissue autofluorescence (<5 ns). By combining a pulsed excitation source to a time-gated fluorescence imaging system, we show that we can efficiently discriminate the intracellular QDs signal from autofluorescence in an ex vivo sample and thus increase the detection sensitivity of labelled cells into tissues. We also report preliminary results obtained in an in vivo sample.
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https://pastel.archives-ouvertes.fr/tel-01083824
Contributor : Sophie Bouccara <>
Submitted on : Tuesday, November 18, 2014 - 10:17:51 AM
Last modification on : Thursday, July 4, 2019 - 11:00:07 AM
Long-term archiving on : Thursday, February 19, 2015 - 3:00:22 PM

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  • HAL Id : tel-01083824, version 1

Citation

Sophie Bouccara. Time-gated detection of near-infrared emitting quantum dots for in vivo cell tracking. Life Sciences [q-bio]. Université Paris Diderot, 2014. English. ⟨tel-01083824⟩

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