Nanotechnology Now





Heifer International

Wikipedia Affiliate Button


DHgate

Home > Press > Nanoshell-emitters hybrid nanoobject was proposed as promising 2-photon fluorescence probe

This is a schematic presentation of plasmonic-enhanced two-photon fluorescence of a single emitter inside or outside of an individual gold nanoshell.

Credit: ©Science China Press
This is a schematic presentation of plasmonic-enhanced two-photon fluorescence of a single emitter inside or outside of an individual gold nanoshell.

Credit: ©Science China Press

Abstract:
Two-photon excitation fluorescence is growing in popularity in the bioimaging field but is limited by fluorophores' extremely low two-photon absorption cross-section. The researcher Dr. Guowei Lu and co-workers from State Key Laboratory for Mesoscopic Physics, Department of Physics, Peking University, are endeavoring to develop efficient fluorescent probes with improved two-photon fluorescence (TPF) performance. They theoretically present a promising bright probe using gold nanoshell to improve the TPF performances of fluorescent emitters. Their work, entitled "Plasmonic-Enhanced Two-Photon Fluorescence with Single Gold Nanoshell", was published in SCIENCE CHINA Physics, Mechanics & Astronomy.2014, Vol 57(6).

Nanoshell-emitters hybrid nanoobject was proposed as promising 2-photon fluorescence probe

Shenyang, PR China | Posted on May 22nd, 2014

The strategy of using metallic nanoparticles to achieve the TPF enhancement is an appealing scheme so-called metal-enhanced fluorescence. It is based on the coupling of the fluorophores and the plasmonic nanoparticles, resulting in enhanced fluorescence intensity, shortened fluorescence lifetime, and extended photostability. Specifically, the fluorescence enhancement can be optimally controlled through simultaneous efficient coupling between the excitation and emission processes of emitters and the dipolar and quadrupolar modes of the nanoparticles, respectively.

Among various types of metal nanoparticles, metallic nanoshells are especially suitable as the carriers of fluorescent emitters to construct hybrid TPF probes, because their plasmon resonance bands easily span the near-infrared region where biological tissues display minimal autofluorescence and absorption. The nanoshells act as optical antenna enabling the local field enhancement, the increase in radiative decay rate of the fluorophore that alters the quantum efficiency, and modulation of the far-field radiative coupling of fluorescence emission through nanoparticle scattering. Also, the core shell structure offers a perfect platform for designing and fabricating multifunctional nanoparticles.

The Peking University researchers employed the finite-difference time-domain method to systematically evaluate the two-photo fluorescence behavior of single emitter single nanoshell configuration. Simultaneous excitation and emission enhancements could be achieved by the suitable dimensions of the nanoshell. They found that the emitter located inside or outside the nanoshell at various positions led to significantly different enhancement effect. (as shown in the Figure).

The fluorescent emitter placed outside the nanoshell can achieve large fluorescence intensity given that both the position and orientation of the emission dipole are optimally controlled, but the TPF enhancement decays rapidly with the increase of distance between the emitter and the shell surface. In contrast, for the case of the emitter placed inside the nanoshell, it can experience substantial two-photon fluorescence enhancement without strict requirements upon the position and dipole orientations, the radiative light can be coupled efficiently with the far field. Besides, the metal shell protects the encapsulated fluorophores from the external environment. The stability of fluorophores can be improved by the strong coupling between the fluorophores and the nanoshell resulting in a shorter fluorescence lifetime. These considerations imply that fluorophores encapsulated in metallic nanoshells is a more desirable nanocomposite configuration for the TPF probe in bioimaging applications.

This work provides a comprehensive understanding about the plasmonic-enhanced two-photon fluorescence behaviors, and the nanocomposite configuration has great potential for optical detecting, imaging and sensing in biological applications.

###

The paper's co-authors are Peking University graduate students Zhang Tianyue, Shen Hongming and collaborative scientists Perriat, P.; Martini, M.; Tillement, O. from CNRS, France. This research project was supported by a grant from the National Natural Science Foundation of China and the National Key Basic Research Program of China.

####

For more information, please click here

Contacts:
LU Guowei

Copyright © Science China Press

If you have a comment, please Contact us.

Issuers of news releases, not 7th Wave, Inc. or Nanotechnology Now, are solely responsible for the accuracy of the content.

Bookmark:
Delicious Digg Newsvine Google Yahoo Reddit Magnoliacom Furl Facebook

Related Links

See the article: ZHANG TianYue, LU GuoWei, SHEN HongMing, Perriat P, Martini M, Tillement O, GONG QiHuang. Plasmonic-enhanced two-photon fluorescence with single gold nanoshell. SCIENCE CHINA Physics, Mechanics & Astronomy, 2014, 57 (6): 1038-1045:

Related News Press

News and information

Compact, Low Cost, Accurate: Mini Positioning Stages, by PI June 30th, 2015

NEI Announces the Issuance of Multiple Patents on Self-Healing & Superhydrophobic Coatings June 30th, 2015

Philips Introduces Quantum Dot TV with Color IQ™ Technology from QD Vision: Manufacturer is first to offer quantum dot displays for both TVs and monitors June 30th, 2015

Oxford Instruments’ TritonXL Cryofree dilution refrigerator selected for the Oxford NQIT Quantum Technology Hub project June 30th, 2015

Visible Light-Sensitive Photocatalysts Used for Purification of Contaminated Water in Iran June 30th, 2015

Imaging

Carnegie Mellon chemists characterize 3-D macroporous hydrogels: Methods will allow researchers to develop new 'smart' materials June 30th, 2015

How Graphene–based Nanomaterials and Films Revolutionize Science Explained in July 9 Webinar Hosted by Park Systems June 29th, 2015

Sensors

Carnegie Mellon chemists characterize 3-D macroporous hydrogels: Methods will allow researchers to develop new 'smart' materials June 30th, 2015

Visible Light-Sensitive Photocatalysts Used for Purification of Contaminated Water in Iran June 30th, 2015

Graphene breakthrough as Bosch creates magnetic sensor 100 times more sensitive than silicon equivalent June 28th, 2015

The peaks and valleys of silicon: Team of USC Viterbi School of Engineering Researchers introduce new layered semiconducting materials as silicon alternative June 27th, 2015

Discoveries

Carnegie Mellon chemists characterize 3-D macroporous hydrogels: Methods will allow researchers to develop new 'smart' materials June 30th, 2015

Chitosan coated, chemotherapy packed nanoparticles may target cancer stem cells June 30th, 2015

Graphene flexes its electronic muscles: Rice-led researchers calculate electrical properties of carbon cones, other shapes June 30th, 2015

Researchers from the UCA, key players in a pioneering study that may explain the origin of several digestive diseases June 30th, 2015

Announcements

BASF and Fraunhofer IPMS-CNT jointly develop electronic materials June 30th, 2015

Graphene flexes its electronic muscles: Rice-led researchers calculate electrical properties of carbon cones, other shapes June 30th, 2015

Researchers from the UCA, key players in a pioneering study that may explain the origin of several digestive diseases June 30th, 2015

Oxford Instruments’ TritonXL Cryofree dilution refrigerator selected for the Oxford NQIT Quantum Technology Hub project June 30th, 2015

Interviews/Book Reviews/Essays/Reports/Podcasts/Journals/White papers

Carnegie Mellon chemists characterize 3-D macroporous hydrogels: Methods will allow researchers to develop new 'smart' materials June 30th, 2015

Chitosan coated, chemotherapy packed nanoparticles may target cancer stem cells June 30th, 2015

Graphene flexes its electronic muscles: Rice-led researchers calculate electrical properties of carbon cones, other shapes June 30th, 2015

Researchers from the UCA, key players in a pioneering study that may explain the origin of several digestive diseases June 30th, 2015

Nanobiotechnology

Nanometric sensor designed to detect herbicides can help diagnose multiple sclerosis June 23rd, 2015

Newly-Developed Biosensor in Iran Detects Cocaine Addiction June 23rd, 2015

Researchers first to show that Saharan silver ants can control electromagnetic waves over an extremely broad range of the electromagnetic spectrum—findings may lead to biologically inspired coatings for passive radiative cooling of objects June 19th, 2015

Cellulose from wood can be printed in 3-D June 17th, 2015

Photonics/Optics/Lasers

Making new materials with micro-explosions: ANU media release: Scientists have made exotic new materials by creating laser-induced micro-explosions in silicon, the common computer chip material June 29th, 2015

Opening a new route to photonics Berkeley lab researchers find way to control light in densely packed nanowaveguides June 27th, 2015

The quantum spin Hall effect is a fundamental property of light June 25th, 2015

Laser spectroscopy: A novel microscope for nanosystems June 25th, 2015

NanoNews-Digest
The latest news from around the world, FREE




  Premium Products
NanoNews-Custom
Only the news you want to read!
 Learn More
NanoTech-Transfer
University Technology Transfer & Patents
 Learn More
NanoStrategies
Full-service, expert consulting
 Learn More










ASP
Nanotechnology Now Featured Books




NNN

The Hunger Project