Ratiometric fluorescence imaging for sodium selenite in living cells

Sodium selenite as a common selenium-containing agent has been extensively studied for human health, especially cancer prevention and treatment. However, precisely evaluating the dynamic changes of sodium selenite at cellular and molecular level in these pharmacological and pathophysiological studies is still challenging. Developing the chemical tools that enable the quantification of sodium selenite in vivo with high spatial and temporal fidelity thus can provide an efficient solution to this challenge. Here, we report the design, synthesis and biological evaluation of ratiometric sodium selenite fluorescent probe (HBTN-Se) for quantitative ratiometric fluorescence imaging of sodium selenite concentration fluctuations in living cells. A strategy for sodium selenite quantification has been achieved effectively through using a highly selective, rapid and biocompatible hydroxyl-deprotecting reaction. The ratiometric fluorescence imaging with HBTN-Se is constructed to precisely monitor changes in sodium selenite levels in living cells. Moreover, HBTN-Se is capable of visualizing differences in sodium selenite levels between normal cells and cancer cells, establishing the utility of this ratiometric detection platform for assessing the correlation between physiological effects of sodium selenite and its levels in living cells.