Synthesis, Photophysical Properties, and Cytotoxicity of Rhodamine Based Fluorescent Probes

Rhodamine derivatives are heterocyclic compound, related to the fluorescent probe having a profound application in the field of biotechnology. Herein, we present two new synthesized rhodamine based fluorescent probes from the rhodamine B (probe 1) and rhodamine 6G (probe 2), respectively. The structures of the synthesized probes 1 and 2 were confirmed using 1H NMR and LC-MS spectral techniques. Further, photophysical properties such as absorption, emission and fluorescence lifetime were examined and compared for both the probes under identical conditions. These comparable data provide a possibility to discuss the mechanism which controls the fluorescence properties of probes. The data also showed that the probes in different solvent environment induce a gradual change in the molecular structure and produce a change in fluorescent intensity as a sensory signal. The changes in fluorescence lifetime and quantum yield with the parent compounds are because of change in solvent polarity and also due to the rigidity of the alkyl groups on N atoms in molecular structure. Moreover, the cell imaging and cellular toxicity studies using the probes were performed. Notably, the result obtained in this study suggests that the probe 2 has significant application in the field of cellular imaging or biotechnology.