Nanotechnology Now

Our NanoNews Digest Sponsors

Heifer International

Wikipedia Affiliate Button

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

Quantum twisted Loong confirms the physical reality of wavefunctions September 23rd, 2017

Application of air-sensitive semiconductors in nanoelectronics: 2-D semiconductor gallium selenide in encapsulated nanoelectronic devices September 22nd, 2017

Researchers set time limit for ultrafast perovskite solar cells September 22nd, 2017

DNA triggers shape-shifting in hydrogels, opening a new way to make 'soft robots' September 21st, 2017

Imaging

Graphene based terahertz absorbers: Printable graphene inks enable ultrafast lasers in the terahertz range September 13th, 2017

Chemical hot spots: Scanning tunneling microscopy measurements identify active sites on catalyst surfaces September 7th, 2017

Phenom-World selects Deben to supply a tensile stage as an accessory to their range of desktop SEMs August 29th, 2017

What the world's tiniest 'monster truck' reveals August 24th, 2017

Sensors

Leti Develops Proof of Concept to Test Wireless Systems in Aircraft: Will Present Results of Joint Project at AeroTech Conference And Exhibition in Fort Worth, Texas, Sept. 26-28 September 20th, 2017

Research shows how DNA molecules cross nanopores: Study could inform biosensors, manufacturing, and more September 5th, 2017

Leti and Partners in PiezoMAT Project Develop New Fingerprint Technology for Highly Reliable Security and ID Applications: Ultra-high Resolution Pressure Sensing Uses Matrices of Vertical Piezoelectric Nanowire To Reconstruct the Smallest Features of Human Fingerprints September 5th, 2017

New results reveal high tunability of 2-D material: Berkeley Lab-led team also provides most precise band gap measurement yet for hotly studied monolayer moly sulfide August 26th, 2017

Discoveries

Quantum twisted Loong confirms the physical reality of wavefunctions September 23rd, 2017

Application of air-sensitive semiconductors in nanoelectronics: 2-D semiconductor gallium selenide in encapsulated nanoelectronic devices September 22nd, 2017

Researchers set time limit for ultrafast perovskite solar cells September 22nd, 2017

DNA triggers shape-shifting in hydrogels, opening a new way to make 'soft robots' September 21st, 2017

Announcements

Quantum twisted Loong confirms the physical reality of wavefunctions September 23rd, 2017

Application of air-sensitive semiconductors in nanoelectronics: 2-D semiconductor gallium selenide in encapsulated nanoelectronic devices September 22nd, 2017

Researchers set time limit for ultrafast perovskite solar cells September 22nd, 2017

DNA triggers shape-shifting in hydrogels, opening a new way to make 'soft robots' September 21st, 2017

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

Quantum twisted Loong confirms the physical reality of wavefunctions September 23rd, 2017

Application of air-sensitive semiconductors in nanoelectronics: 2-D semiconductor gallium selenide in encapsulated nanoelectronic devices September 22nd, 2017

Researchers set time limit for ultrafast perovskite solar cells September 22nd, 2017

DNA triggers shape-shifting in hydrogels, opening a new way to make 'soft robots' September 21st, 2017

Nanobiotechnology

DNA triggers shape-shifting in hydrogels, opening a new way to make 'soft robots' September 21st, 2017

Do titanium dioxide particles from orthopedic implants disrupt bone repair? September 16th, 2017

Applications for the nanomedTAB are open until September 18th, 2017 September 13th, 2017

Magnetic cellular 'Legos' for the regenerative medicine of the future September 12th, 2017

Photonics/Optics/Lasers

Quantum twisted Loong confirms the physical reality of wavefunctions September 23rd, 2017

Application of air-sensitive semiconductors in nanoelectronics: 2-D semiconductor gallium selenide in encapsulated nanoelectronic devices September 22nd, 2017

Physicists develop new recipes for design of fast single-photon gun Physicists develop high-speed single-photon sources for quantum computers of the future September 21st, 2017

A new approach to ultrafast light pulses: Unusual fluorescent materials could be used for rapid light-based communications systems September 19th, 2017

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