Research in the Xu group is focused on the development of new fluorescent dyes to explore biology. We are discovering and revealing new fluorescence mechanisms and the structural and environmental dependence of absorption and fluorescence, which can be applied in the study of interaction between fluorescent dyes and biomolecules. Through the thorough understanding of the structure-fluorescence relationship of dyes, we are developing new dyes for single-molecule and super-resolution fluorescence imaging, with the required time resolution and long-term dynamic imaging capability.