Nanotechnology Now

Our NanoNews Digest Sponsors



Heifer International

Wikipedia Affiliate Button


android tablet pc

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

University of Minnesota engineers make sound loud enough to bend light on a computer chip: Device could improve wireless communications systems November 28th, 2014

Study details laser pulse effects on behavior of electrons November 28th, 2014

Single-atom gold catalysts may offer path to low-cost production of fuel and chemicals November 28th, 2014

Production of Anticancer Drug from Nanofibers in Iran November 28th, 2014

Imaging

Renishaw receives Queen's Award for spectroscopy developments November 25th, 2014

A*STAR SIMTech wins international award for breaking new ground in actuators: SIMTech invention can be used in an array of industries, and is critical for next generation ultra-precision systems November 24th, 2014

Professional AFM Images with a Three Step Click SmartScan by Park Systems Revolutionizes Atomic Force Microscopy by Automatizing the Imaging Process November 24th, 2014

Characterization of X-ray flashes open new perspectives in X-ray science: Ultra-short X-ray pulses explore the nano world November 24th, 2014

Sensors

Lawrence Livermore researchers develop efficient method to produce nanoporous metals November 25th, 2014

Cooling with the coldest matter in the world November 24th, 2014

Canatu Launches CNB In-Mold Film for Transparent Touch on 3D Surfaces –in Cars, Household Appliances, Wearables, Portables November 20th, 2014

UO-industry collaboration points to improved nanomaterials: University of Oregon microscope puts spotlight on the surface structure of quantum dots for designing new solar devices November 20th, 2014

Discoveries

University of Minnesota engineers make sound loud enough to bend light on a computer chip: Device could improve wireless communications systems November 28th, 2014

Study details laser pulse effects on behavior of electrons November 28th, 2014

Production of Anticancer Drug from Nanofibers in Iran November 28th, 2014

The mysterious 'action at a distance' between liquid containers November 26th, 2014

Announcements

University of Minnesota engineers make sound loud enough to bend light on a computer chip: Device could improve wireless communications systems November 28th, 2014

Study details laser pulse effects on behavior of electrons November 28th, 2014

Single-atom gold catalysts may offer path to low-cost production of fuel and chemicals November 28th, 2014

Production of Anticancer Drug from Nanofibers in Iran November 28th, 2014

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

University of Minnesota engineers make sound loud enough to bend light on a computer chip: Device could improve wireless communications systems November 28th, 2014

Study details laser pulse effects on behavior of electrons November 28th, 2014

Single-atom gold catalysts may offer path to low-cost production of fuel and chemicals November 28th, 2014

Production of Anticancer Drug from Nanofibers in Iran November 28th, 2014

Nanobiotechnology

Quantum mechanical calculations reveal the hidden states of enzyme active sites November 20th, 2014

Tokyo Institute of Technology research: Protein-engineered cages aid studies of cell functions November 19th, 2014

A novel method for identifying the body’s ‘noisiest’ networks November 19th, 2014

Implementation of DNA Chains in Designing Nanospin Pieces November 9th, 2014

Photonics/Optics/Lasers

Study details laser pulse effects on behavior of electrons November 28th, 2014

NRL Scientists Discover Novel Metamaterial Properties within Hexagonal Boron Nitride November 20th, 2014

Penn engineers efficiently 'mix' light at the nanoscale November 17th, 2014

'Direct writing' of diamond patterns from graphite a potential technological leap November 5th, 2014

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







© Copyright 1999-2014 7th Wave, Inc. All Rights Reserved PRIVACY POLICY :: CONTACT US :: STATS :: SITE MAP :: ADVERTISE