Chemigenetic Nanoprobe for Proximity Sensing Dynamics of Lactate Efflux

Lactate metabolism, a fundamental process in the biological system, plays a crucial role in cell fate decisions and metabolic homeostasis. However, the inherent features of the lactate metabolite, especially its dynamic efflux behavior, present significant hurdles in probe chemistry for monitoring the subtle fluctuation of lactate in cells. Herein, we report a membrane-localized lactate-responsive chemigenetic nanoprobe with high photostability for the proximity sensing of lactate efflux dynamics. By covalently conjugating acid-responsive persistent luminescent nanoparticles Mn²⁺-doped Zn₂GeO₄ (ZGOM) to a carboxylated HaloTag ligand (ZGOM@L) and a protein tag (HaloTag) that is genetically fused to lactate transporter-associated protein (CD147) subsequently, we obtained the chemigenetic nanoprobe ZGOM@L-HC. Upon attaching on the cell membrane, ZGOM@L-HC exhibited an enhanced luminescence characteristic, allowing for ultrafast response (10 s) to the acidic tumor microenvironment. Such ultrahigh sensitivity enables ZGOM@L-HC to proximally monitor the dynamics of endogenous lactate fluctuation in drug-treated living cells. For the first time, we demonstrated the use of a chemigenetic nanoprobe to visualize therapy-induced lactate acidification in the early phase arising from pharmacological activation of glycolytic signaling pathways. This chemigenetic nanoprobe design strategy would greatly facilitate the advancement of profiling lactate metabolism in basic life science and medicine research.