Lanthanide-Doped Near-Infrared Nanoparticles for Biophotonics

Light in the near-infrared (NIR) spectral region is increasingly utilized in bioapplications, providing deeper penetration in biological tissues owing to the lower absorption and scattering in comparison with light in the visible range. Lanthanide-doped luminescent nanoparticles with excitation and/or emission in the NIR range have recently attracted tremendous attention as one of the prime candidates for noninvasive biological applications due to their unique optical properties, such as large Stokes shift, spectrally sharp luminescence emissions, long luminescence lifetimes, and excellent photostability. Herein, recent advances of lanthanide-doped nanoparticles with NIR upconversion or downshifting luminescence and their uses in cutting-edge biophotonic applications are presented. A set of efficient strategies for overcoming the fundamental limit of low luminescence brightness of lanthanide-doped nanoparticles is introduced. An in-depth literature review of their state-of-art biophotonics applications is also included, showing their superiority for high-resolution imaging, single-nanoparticle-level detection, and efficacy for tissue-penetrating diagnostics and therapeutics.

Automated summary

Light in the near-infrared (NIR) spectral region is increasingly used in bioapplications due to its deeper penetration in biological tissues. Lanthanide-doped luminescent nanoparticles with excitation and/or emission in the NIR range are gaining attention for noninvasive biological applications, offering unique optical properties such as large Stokes shift, sharp luminescence emissions, long lifetimes, and photostability. Advanced strategies for enhancing the luminescence brightness of these nanoparticles have been introduced, along with a review of their superior biophotonic applications in high-resolution imaging, single-nanoparticle-level detection, and tissue-penetrating diagnostics and therapeutics.