Ultrabright Silica-Coated Organic Nanocrystals for Two-Photon In Vivo Imaging

Abstract

Herein, we demonstrate the potential of ultrabright fluorescent silica-coated organic nanocrystals for two-photon in vivo imaging. These unique nanoparticles (NPs) containing a crystalline core of small push-pull dipolar dye are specifically designed to exhibit two-photon absorption for 2 fluorescence imaging. The NPs can be easily functionalized using click chemistry in pure water, with preservation of the organic core. A novel small-volume DLS technique was used to evaluate the effect of PEGylation on the colloidal stability of the NPs in complex media containing salts and proteins, mimicking the composition of blood serum. The potential of these bright red-emitting NPs for two-photon fluorescence imaging is demonstrated both in vitro and in vivo.

Organic Nanoparticle Tracking During Pharmacokinetic Studies

“…[129] In 2020, Perdoor et al were able to observe the in vivo transcranial flow of individual NPs through the bloodstream 30 seconds after injection in a mouse. [130] In another study, Alifu et al showed that twophoton fluorescence imaging can be used for in vivo tracking of organic NPs up to 1200 µm in the brain blood vessels of a mouse. [131] These two studies look very promising for in vivo use, as 2-PFM can be employed either for imaging ear blood vessel or for brain blood vessels.…”

Silica Nanoparticles Decorated with Gadolinium Oxide Nanoparticles for Magnetic Resonance and Optical Imaging of Tumors

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