Structurally Characterized Zn2+ Selective Ratiometric Fluorescence Probe in 100 % Water for HeLa Cell Imaging: Experimental and Computational Studies

Fluorescence recognition of Zn2+ in 100% aqueous medium using 2-((1, 3 dihydroxy-2-(hydroxymethyl)propan-2 ylimino) methyl) phenol (SALTM) as ratiometric probe is reported. Moreover, SALTM can discriminate Zn2+ from Cd2+very effectively. The binding constant and detection limit of the probe for Zn2+ is 2.2×10(4) M(-1/2) and 2.79×10(-8) M respectively.Interestingly, corresponding naphthalene derivative(HNTM) having less water solubility fails to be a ratiometric sensor. SALTM can detect intracellular Zn2+ in HeLa cervical cancer cells under fluorescence microscope. Moreover, DFT and TD-DFT studies support experimental findings.