On The Rare Earth Conversion Luminescent Nanomaterials For Small Animal Imaging Of Lymphatic System Research

Lymphography is often used for the diagnosis of lymphatic metastasis in oncology. Fluorescent bioimaging is a unique approach to visualize the details in cell and animal models in vivo. It is a challenge to improve signal-to-noise ratio and light penetration in fluorescent bioimaging. Tm3+-doped rare-earth upconversion nanophosphors (UCNPs) under continuous-wave (CW) excitation at980nm display unique upconversion luminescence peaked at800nm, and becoming one of the most promising classes of luminescent labels. This thesis is focused on the application of UCNPs in lymphatic image and composed of two parts.I. Upconversion nanophosphors for the lymph node image in vivo.Using UCNPs as luminescent probes, multiply drainage lymph nodes from different lymphatic basins in animal models (nude mouse, Kun-ming mouse, rats, rabbit) have been visualized real-time in vivo. UCNPs provides great tendency toward lymph system with high signal-to-noise ratio. Furthermore, water-soluble nanophosphors with size of20-42nm is indicated as the optimized candidate for lymphatic image.II. Hyaluronic acid coated upconversion nanophosphors for the lymphatic vessel target image in vivo.Hyaluronic acid (HA) coated upconversion nanophosphors (HA-UCNPs) have been synthesized through electrostatic interaction. The as-prepared HA-UCNPs are well dispersed in water and have excellent photostability. Because of the special affinity between HA and lymphatic endothelial cells hyaluronic acid receptor-1(LYVE-1), the lymphatic vessel in vivo was achieved by using HA-UCNPs as luminescent probe. Furthermore, the lymphatic system can be long-term monitored real-time for24h.