Lanthanide-Doped Upconversion Nanoparticles Meet the Needs for Cutting-Edge Bioapplications: Recent Progress and Perspectives

The rise of biological frontier fields such as precision theranostics, gene editing, optogenetics, etc. introduces the best opportunities and unprecedented challenges at the same time to the bioapplication of luminescent nanomaterials. Because of the merits of photon upconversion characteristics and high stability, tunable structure and excitation dynamics, and sharp emissions, the lanthanide-doped upconversion nanoparticle (UCNP) is considered to be a highly competitive candidate to meet these challenges. Indeed, UCNPs have attracted extensive attention in diverse cutting-edge bioapplication fields ranging from near-zero background biosensing, deep tissue bioimaging, precision nanomedicine, and remote biomanipulation since the first development in the early 2000s. Recently, with the increasing maturity of upconversion synthesis technology and the deep integration of multiple disciplines, the biological application research of upconversion has achieved many new breakthroughs. Herein, we summarize the latest bioapplication research progress of UCNPs in the fields of sensing, imaging, therapy, optogenetics, etc. Ultimately, current challenges and perspectives in this field are discussed.