Self-Assembly and Photophysical Studies of an Unusual Red Colored Dye Which Show Green Fluorescence in Cell Imaging

We report for the very first time self-assembly of a red color dye 7-Amino-6h-anthra[9,1-cd][1,2]thiazol-6-one (AAT),its photophysical properties and its applications in cell imaging.Interestingly, AAT show intense red colour in visible light while it shows the orange colour fluorescence under UV light @312nm.Surprisingly, when this dye was used as cell imaging agent it revealed only green fluorescence inside cells and not red. Hence, the photophysical properties of this dye was very intriguing. Further, when self-assembling properties of this dye was examined it revealed formation of tree like branched structures which appeared red both under green and red filter which was again an unexpected result..Interestingly AAT self-assembly also show morphological transition and the branched tree like structures changes to straight fibres as the solvent is changed from DMSO to THF. Hence, the results of self-assembly and cell imaging were contrary to each other and the photophysical properties of this dye is very unusual as compared to conventional dyes. Our future endeavours willaim to understand this anomalous behaviour in greater details in future through various biophysical assays.