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Depolarization signatures map gold nanorods within biological tissue.

ABSTRACT: Owing to their electromagnetic properties, tunability and biocompatibility, gold nanorods (GNRs) are being investigated as multifunctional probes for a range of biomedical applications. However, detection beyond the reach of traditional fluorescence and two-photon approaches and quantitation of their concentration in biological tissue remain challenging tasks in microscopy. Here we show how the size and aspect ratio that impart GNRs with their plasmonic properties also make them a source of entropy. We report on how depolarization can be exploited as a strategy to visualize GNR diffusion and distribution in biologically relevant scenarios ex vivo, in vitro and in vivo. We identify a deterministic relation between depolarization and nanoparticle concentration. As a result, some of the most stringent experimental conditions can be relaxed, and susceptibility to artefacts is reduced, enabling microscopic and macroscopic applications.

SUBMITTER: Lippok N

PROVIDER: S-EPMC5703429 | biostudies-literature | 2017

REPOSITORIES: biostudies-literature

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Depolarization signatures map gold nanorods within biological tissue.

Lippok Norman N Villiger Martin M Albanese Alexandre A Meijer Eelco F J EFJ Chung Kwanghun K Padera Timothy P TP Bhatia Sangeeta N SN Bouma Brett E BE

Nature photonics 20170731

Owing to their electromagnetic properties, tunability and biocompatibility, gold nanorods (GNRs) are being investigated as multifunctional probes for a range of biomedical applications. However, detection beyond the reach of traditional fluorescence and two-photon approaches and quantitation of their concentration in biological tissue remain challenging tasks in microscopy. Here we show how the size and aspect ratio that impart GNRs with their plasmonic properties also make them a source of entr ...[more]

PMID: 29201136

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