Emerging biomaterials: Taking full advantage of the intrinsic properties of rare earth elements

Due to the prominent optical, magnetic, and X-ray attenuation properties of RE elements, as well as the radioactivity of their isotopes, RE-containing biomaterials are becoming increasingly popular in the biological field. To date, some RE-containing biomaterials, such as Gadolinium (III) 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetate (Gd-DOTA, contrast agent for magnetic resonance imaging) and 177Lu-Dotatate (clinical medicine for radiation therapy) have been commercialized, but most are still in laboratories and preclinical trials. The purpose of this review is to provide a general and comprehensive overview of the recent developments of RE-containing materials in bioimaging, therapy, and biosensing originating from the intrinsic properties of RE elements. Furthermore, the challenges and opportunities of RE-containing materials in the above rapidly growing biological field were discussed. This review will be useful to chemists, biochemists, physicalists, materials scientists, and other researchers interested in the applications of RE-containing materials in the biological field.