Rare-earth (RE) chemical elements are rich in optical and magnetic properties owing to the unique properties of 4f-electron and have been widely used in catalysts, magnets, phosphors, etc. Recent breakthroughs in synthesizing high quality RE nanomaterials with uniform size and shape have triggered exploration of their biological and biomedical applications. Following on from our previous investigations on the preparation and the in vivo tumor detection of magnetic and luminescent materials, and the recent development based on the rare earth magnetic and upconversion luminescence nanoparticles, we are invited to write a research news articles to Advanced Materials for the ICCAS2 special issue. This Research News summarizes the recent achievements in controlled synthesis of magnetic and luminescent RE nanoparticles, surface modification, and toxicity studies of RE nanomaterials, and highlights the state-of-the-art in in vivo applications of RE nanoparticles.
    This work is accomplished with the huge help of Prof. Mingyuan Gao. He devoted a lot of his time and energy on conceiving the manuscript, discussing, revising and improving the manuscript. Thanks to his patient guidance, and my abilities on research and cooperation have been greatly improved.
                                                                                                                                                                                                          Chunyan Liu et al.