Dual-Locked Small Molecule Fluorescent Probe for Precise Disease Imaging

Fluorescence imaging is an indispensable tool for noninvasive visualization of biomolecules in living systems, offering high sensitivity for disease diagnosis and image-guided therapy. Compared to conventional "always-on" fluorescent probes, small molecule single-locked probes achieve higher detection sensitivity and imaging quality by specifically triggering optical signals upon encountering target biomarkers. However, their utility is often compromised by false-positive signals generated in healthy tissues due to the expression of nontarget biomarkers. In contrast, dual-locked fluorescent probes, designed to detect two biomarkers simultaneously, provide significantly enhanced specificity for identifying precise bio molecule events or pathological conditions. This review discusses recent progress in developing dual-locked fluorescent probes for biological imaging, with a focus on their diverse chemical structures and design strategies. Finally, we discuss current challenges and potential future directions for applying these probes in complex biological systems.