Studies on fluorescent molecular rotors as environment-sensitive probes

Abstract

Fluorescence small molecules or so-called environmental probes that could change their photophysical characteristics in response to physicochemical changes, have been widely used in various areas of sciences, engineering and medicine. In this work, the characterization and properties of BODIPY-based probes is studied, where it was found that the presence of 1,1-dichloroethane induces spectroscopic differentiation between aggregated and monomeric forms of BODIPY dyes (Chapter 2). A trimeric BODIPY rotor with a high extinction coefficients was developed and the fluorescence measurements established that the trimer could be used as a viscometer for molecular solvents, membranelike environments and cancer cell lines (Chapter 3.1). Also, the use of a structural simple BODIPY-based rotor to map the viscosity of intragranular mucin matrices in bronchial epithelial cells using fluorescence lifetime imaging microscopy was demonstrated (Chapter 3.2). Finally, porphyrin rotor in organogels was evaluated in a temperature dependent manner (Chapter 4). Overall, BODIPY and prophyrin molecular rotors were studied as chemical probes in diverse systems. The results indicated an intricate complexity of the environmental factors on the conformation integrity of molecular rotors, which often are used as molecular viscometers.