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Nanowires for Biosensing: Lightguiding of Fluorescence as a Function of Diameter and Wavelength.

ABSTRACT: Semiconductor nanowires can act as nanoscaled optical fibers, enabling them to guide and concentrate light emitted by surface-bound fluorophores, potentially enhancing the sensitivity of optical biosensing. While parameters such as the nanowire geometry and the fluorophore wavelength can be expected to strongly influence this lightguiding effect, no detailed description of their effect on in-coupling of fluorescent emission is available to date. Here, we use confocal imaging to quantify the lightguiding effect in GaP nanowires as a function of nanowire geometry and light wavelength. Using a combination of finite-difference time-domain simulations and analytical approaches, we identify the role of multiple waveguide modes for the observed lightguiding. The normalized frequency parameter, based on the step-index approximation, predicts the lightguiding ability of the nanowires as a function of diameter and fluorophore wavelength, providing a useful guide for the design of optical biosensors based on nanowires.

SUBMITTER: Verardo D

PROVIDER: S-EPMC6377180 | biostudies-literature | 2018 Aug

REPOSITORIES: biostudies-literature

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Nanowires for Biosensing: Lightguiding of Fluorescence as a Function of Diameter and Wavelength.

Verardo Damiano D Lindberg Frida W FW Anttu Nicklas N Niman Cassandra S CS Lard Mercy M Dabkowska Aleksandra P AP Nylander Tommy T Månsson Alf A Prinz Christelle N CN Linke Heiner H

Nano letters 20180717 8

Semiconductor nanowires can act as nanoscaled optical fibers, enabling them to guide and concentrate light emitted by surface-bound fluorophores, potentially enhancing the sensitivity of optical biosensing. While parameters such as the nanowire geometry and the fluorophore wavelength can be expected to strongly influence this lightguiding effect, no detailed description of their effect on in-coupling of fluorescent emission is available to date. Here, we use confocal imaging to quantify the ligh ...[more]

PMID: 30001138

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Dataset Information

Nanowires for Biosensing: Lightguiding of Fluorescence as a Function of Diameter and Wavelength.

Publications

Nanowires for Biosensing: Lightguiding of Fluorescence as a Function of Diameter and Wavelength.

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