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Nanosecond time scale transient optoplasmonic detection of single proteins.

ABSTRACT: Optical detection of individual proteins with high bandwidth holds great promise for understanding important biological processes on the nanoscale and for high-throughput fingerprinting applications. As fluorescent labels impose restrictions on detection bandwidth and require time-intensive and invasive processes, label-free optical techniques are highly desirable. Here, we read out changes in the resonantly scattered field of individual gold nanorods interferometrically and use photothermal spectroscopy to optimize the experiment’s parameters. This interferometric plasmonic scattering enables the observation of single proteins as they traverse plasmonic near fields of gold nanorods with unprecedented temporal resolution in the nanosecond-to-microsecond range.

SUBMITTER: Baaske MD

PROVIDER: S-EPMC8759745 | biostudies-literature | 2022 Jan

REPOSITORIES: biostudies-literature

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Nanosecond time scale transient optoplasmonic detection of single proteins.

Baaske Martin D MD Asgari Nasrin N Punj Deep D Orrit Michel M

Science advances 20220114 2

Optical detection of individual proteins with high bandwidth holds great promise for understanding important biological processes on the nanoscale and for high-throughput fingerprinting applications. As fluorescent labels impose restrictions on detection bandwidth and require time-intensive and invasive processes, label-free optical techniques are highly desirable. Here, we read out changes in the resonantly scattered field of individual gold nanorods interferometrically and use photothermal spe ...[more]

PMID: 35030027

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