Controlling the excitation of upconverting luminescence for biomedical theranostics: neodymium sensitizing

With the rapid development of nanotechnology over the past decade, lanthanide doped upconverting nanoparticles (UCNPs) have been successfully synthesized and have emerged as an important class of nanomaterials. In contrast to the traditional Yb3+-sensitized UCNPs, the emerging Nd3+-sensitized UCNPs have many merits in controlling the excitation of upconverting luminescence, including minimizing overheating effect, increasing the imaging depth and so on. In this review paper, we provide a comprehensive survey of the most recent advances in developing Nd3+-sensitized UCNPs, which include nanocomposition, mechanisms, and some typical nanostructures of Nd3+-sensitized UCNPs. Furthermore, an important emphasis is placed on various applications including downconversion and upconversion photoluminescence for bioimaging, high-resolution, and deep tissue imaging and tumor diagnosis and therapy. Potential challenges and prospective development are also discussed.