SHG nanoprobes: Advancing harmonic imaging in biology

Second harmonic generating (SHG) nanoprobes have recently emerged as versatile and durable labels suitable for in vivo imaging, circumventing many of the inherent drawbacks encountered with classical fluorescent probes. Since their nanocrystalline structure lacks a central point of symmetry, they ar...

Full description

Saved in:
Bibliographic Details
Published in:BioEssays 2012-05, Vol.34 (5), p.351-360
Main Authors: Dempsey, William P., Fraser, Scott E., Pantazis, Periklis
Format: Article
Language:English
Subjects:
animal imaging
Animals
Barium Compounds - chemistry
Fluorescent Dyes - chemistry
fluorescent nanodiamonds
fluorescent proteins
Green Fluorescent Proteins
Microscopy, Confocal - methods
Microscopy, Fluorescence - methods
Molecular Imaging - methods
Nanoparticles - chemistry
nonlinear crystals
Photons
quantum dots
R&D
Research & development
SERS nanoparticles
Signal-To-Noise Ratio
Spectrum Analysis, Raman - methods
Spectrum Analysis, Raman - standards
Titanium - chemistry
upconverting nanoparticles
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Second harmonic generating (SHG) nanoprobes have recently emerged as versatile and durable labels suitable for in vivo imaging, circumventing many of the inherent drawbacks encountered with classical fluorescent probes. Since their nanocrystalline structure lacks a central point of symmetry, they are capable of generating second harmonic signal under intense illumination – converting two photons into one photon of half the incident wavelength – and can be detected by conventional two‐photon microscopy. Because the optical signal of SHG nanoprobes is based on scattering, rather than absorption as in the case of fluorescent probes, they neither bleach nor blink, and the signal does not saturate with increasing illumination intensity. When SHG nanoprobes are used to image live tissue, the SHG signal can be detected with little background signal, and they are physiologically inert, showing excellent long‐term photostability. Because of their photophysical properties, SHG nanoprobes provide unique advantages for molecular imaging of living cells and tissues with unmatched sensitivity and temporal resolution. SHG nanoprobes are nanoparticles (e.g. crystals such as barium titanate BaTiO3) that produce light through a mechanism known as second harmonic generation (SHG). Because of their photophysical properties they offer unique advantages for molecular imaging studies, especially in single molecule and deep‐tissue imaging.
ISSN:0265-9247
1521-1878
DOI:10.1002/bies.201100106