Luminescent Ultralong Microfibers Prepared through Supramolecular Self-Assembly of Lanthanide Ions and Thymidine in Water

Luminescent materials are of great interest in many fields, such as fluorescent sensing and medical imaging. Here, the construction of lanthanide-based luminescent ultralong microfibers through supramolecular self-assembly (SSA) is reported. Nucleosides (thymidine in particular), the building blocks of nucleic acids, were used as new ligands to mediate the formation of luminescent microfibers in water. The length of microfibers from thymidine-lanthanide ion (Eu and Tb) SSA was on the centimeter scale. Notably, the microfibers exhibited strong luminescence because the lanthanide ions had been chelated, sensitized and effectively protected by thymidine molecules in water. Only when the stoichiometric ratio of lanthanide ion to thymidine was 1:3 and the pH of the solution was 7, are luminescent microfibers formed. Other nucleosides, such as adenosine, cytidine, and guanosine, could not form microfibers with the lanthanide ions. This work opens a new avenue for constructing nucleoside-lanthanide SSA architectures, which hold great potential in biological and optical related applications.