Voltage sensitive dyes in neurology-glimpses from recent developments

摘要

BECAUSE of their great microenvironmental sensitivity, small-molecule fluorophores are appealing molecular tools for environmental sensing applications and biosensing/bioimaging approaches. Through the binding or interaction of various metalions, reactive oxygen species, organic toxins, or cell organelles/membranes fluorescent molecules can either turn on/off their fluorescence or chromically shift their emission, which can considerably improve cell fluorescence microscopic imaging. Fluorescence-rich molecular sensors with large Stokes shifts are useful for these applications, due to the limited overlap between excitation and emission. The majority of these molecular derivatives have push-pull (electron-withdrawing and -donating) functional groups at each end of a -conjugated aromatic core, allowing for intramolecular charge-transfer (ICT) capabilities in the excited state. As a result of the spatially separated and intensified excited-state dipole, such pushpull dyes often display significant solvatofluorochromism and great environmental sensitivity. New push-pull fluorophore discoveries in this field are driven by efforts to enhance ICT character and, therefore, increase their efficacy for monitoring molecular interactions, processes, and other events that require high specificity and environmental sensitivity.