Design and Synthesis of Novel Squaraine Dye with Highly Enhanced Far‐Red Fluorescence and its Interaction with a model protein

Novel amine-functionalized symmetrical SQ-dye and FITC-SQ-FITC dye conjugate were designed successfully synthesized, followed by their structural photophysical characterizations. Symmetrical SQ exhibited complete fluorescence quenching in polar solvents, which was explained considering photoinduced electron transfer (PET) as a dominant pathway. On the other hand, resulted decrease an aggregation of both FITC units about 47 times enhancement far-red appearing at 674 nm. This profound synergistic influence suppression aggregation-induced (ACQ) PET. newly shows PBS owing to very strong aggregation, confirmed spectral absorption investigation. In PBS, it strongly interacts with BSA (Ka = 1.1 × 104 M-1) used model protein breaking increasing associated function concentration. A 117 increase nm 25 concentration suggests is excellent probe for dye-protein interaction. article protected copyright. All rights reserved.