Tang_2025_Spectrochim.Acta.A.Mol.Biomol.Spectrosc_343_126569

Carboxylesterases serve as crucial regulators of metabolic processes and environmental adaptation across species. While significant progress has been made in developing animal-compatible fluorescence probes, real-time monitoring of the catalytic activity of these enzymes in plants remains challenging due to the limited penetration of visible light in plant tissues. Herein, we designed and synthesized TCF-CEs, tricyanofuran-xanthene probes containing carboxylesterase-cleavable ester bonds that triggers near-infrared fluorescence activation within 20 min. The probe demonstrates excellent specificity, low detection limit of 1.18 x 10(-4) U, and negligible cytotoxicity, which enables effective sensing of endogenous carboxylesterase activities in live mammalian cells. Furthermore, salt-stress experiments with Arabidopsis established direct correlations between carboxylesterase levels and plant stress adaptation. As an effective near-infrared probe capable of tracking carboxylesterase activities in both mammalian cells and plant systems, TCF-CEs provides a powerful tool for investigating metabolic responses between organisms and environmental challenges.