Activatable\nMultiplexed <sup>19</sup>F NMR Probes\nfor Dynamic Monitoring of Biomarkers Associated with Cellular Senescence

Simultaneous detection\nof multiple biomarkers is crucial to achieve\nspecific and dynamic analysis of cellular senescence, given its intrinsic\nhigh heterogeneity. Current approaches for senescence detection largely\nrely on fluorescence imaging, but fluorescent probes inevitably suffer\nfrom issues including autofluorescence and spectral overlap when being\napplied for the simultaneous detection of multiple biomarkers. Herein,\nwe report an alternative strategy and design activatable multiplexed\nsenoprobes based on <sup>19</sup>F NMR for dynamic monitoring of cellular\nsenescence. Differing from previous approaches, our strategy has two\nunique advantages. First, this strategy utilizes the changes in the <sup>19</sup>F chemical shift as the signal output, which features by\nits fingerprint and quantifiable characters, thereby significantly\nenhancing the detection throughput toward biomarkers with minimized\nspectral overlapping. Second, the background signal is minimized,\nbenefiting from the extremely low abundance of F in biological samples,\nand the detection accuracy can thus be improved. As a proof of concept,\ntwo activatable <sup>19</sup>F NMR molecular probes are synthesized\nthat specially respond to two key senescence-associated biomarkers\n(β-gal and ROS) and have been successfully demonstrated for\ndynamical and quantitative assessment of the changes of these biomarkers\nin different cellular models of senescence, without causing obvious\ncytotoxicity. Owing to the flexible molecular design, this work may\noffer a useful platform to create diversified <sup>19</sup>F NMR senoprobes\nfor deep understanding of cellular senescence across a wide range\nof aging-related diseases.