Lanthanide-Doped Nanoparticles with Near-Infrared-to-Near-Infrared Luminescence for Bioimaging

Lanthanide (Ln, or rare-earth) doped nanoparticles are well-known for their prominent optical properties and have been widely used for biological applications, especially in biological assays and medical imaging. Recently, the extensive attention of near infrared (NIR) wavelength range has dramatically increased for its fast feedback, high spatial resolution and deep tissue penetration. Tissues have minimal absorbance in this region. While a lot of excellent reviews cover various aspects of biomedical imaging based on lanthanide doped nanoparticles, there has not been a review that systematically summarizes NIR-to-NIR imaging with lanthanide doped nanoparticles. In this review, we focus on the recent development of NIR-to-NIR imaging based on lanthanide doped nanoparticles, and discuss challenges and opportunities in it.