Recent Advances of Upconversion Nanomaterials in the Biological Field
Cunjin Gao, Pengrui Zheng, Quanxiao Liu, Shuang Han, Dongli Li, Shiyong Luo, Hunter Temple, Christina Xing, Jigang Wang, Yanling Wei, Tao Jiang, Wei Chen
Abstract
Rare Earth Upconversion nanoparticles (UCNPs) are a type of material that emits high-energy photons by absorbing two or more low-energy photons caused by the anti-stokes process. It can emit ultraviolet (UV) visible light or near-infrared (NIR) luminescence upon NIR light excitation. Due to its excellent physical and chemical properties, including exceptional optical stability, narrow emission band, enormous Anti-Stokes spectral shift, high light penetration in biological tissues, long luminescent lifetime, and a high signal-to-noise ratio, it shows a prodigious application potential for bio-imaging and photodynamic therapy. This paper will briefly introduce the physical mechanism of upconversion luminescence (UCL) and focus on their research progress and achievements in bio-imaging, bio-detection, and photodynamic therapy.