Carbazole-azine based fluorescence 'off-on' sensor for selective detection of Cu²⁺ and its live cell imaging

A new carbazole-azine based fluorescent sensor was synthesized and characterized. The selectivity of the sensor for Cu²⁺ over other counter ions in a dimethyl sulfoxide/H₂ O mixture was shown through enhancement in fluorescence - an off to on transformation. The specificity of the probe towards Cu²⁺ was evident in ultraviolet/visible, fluorescence, Fourier transform infrared and mass studies. Application of the probe in the cell imaging and cytotoxicity of living cells is illustrated.