BM06: 2D Nanomaterials in Health Care
Isabel Gessner explaining the International Summit

NM07: Nanostructure-Based Optical Bioprobes—Advances, Trends and Challenges in Optical and Multimodular Bioimaging and Sensing

Shangfeng Wang, Fudan University

Ratiometric Imaging of Endogenous Hypochlorous Acid in the Second Near-Infrared Window beyond 1500 nm

Written by Xun Gong

This work reports a fluorescent nanoprobe for the ratiometric detection of reactive oxygen species (ROS) in the second near-infrared window (NIR-II: ∼1000–1700 nm) of lanthanide-based downconversion nanoparticle (NIR-IIb: ~1500-1700 nm). Imaging in NIR-II has many advantages in in vivo imaging including reduced attenuation, tissue scattering, and autofluorescence. The result is higher image quality. To further improve signal, ratiometric sensing is used. By having a built-in control, there is increased signal-to-noise ratio (SNR), decreased photobleaching, and effects of changing particle distributions.

Lanthanides have emission features in the NIR-II window. Downconversion luminescence excited under 808 nm can be effectively quenched by the Cy7.5 chromophores on the surface of nanoparticles through an absorption competition process and subsequently recovered upon the addition of ROS. The downconversion luminescence excited under 980 nm remains unchanged, making a 2 excitation wavelength ratiometric sensor. Optical phantom experiments show no significant signal change within 1-3 mm tissue depths. Finally, LPS injection in mouse studies show lymphnode increase in ROS with SNR of 19.7. This study provides a new design strategies of NIR-II fluorescent probes for precise and reliable measurement in biological systems.


Verify your Comment

Previewing your Comment

This is only a preview. Your comment has not yet been posted.

Your comment could not be posted. Error type:
Your comment has been posted. Post another comment

The letters and numbers you entered did not match the image. Please try again.

As a final step before posting your comment, enter the letters and numbers you see in the image below. This prevents automated programs from posting comments.

Having trouble reading this image? View an alternate.


Post a comment

Your Information

(Name and email address are required. Email address will not be displayed with the comment.)