Expanding the targets of the diaza-18-crown-6 hydroxyquinoline derivatives family to Zn(II) ions for intracellular sensing

We have recently developed an optimised synthetic strategy for the preparation of chemosensors based on the diaza-18- crown-6 hydroxyquinoline structure. This flexible approach allows to obtain a variety of substituted derivatives with improved fluorescence, metal ion binding, uptake and localisation properties. In this context, we have focused our attention on the design of specific chemosensors for intracellular Zn2? ions, because of their important role in many biological processes. Interestingly, among them one in particular shows the properties of making it a promising candidate for effective Zn(II) ions detection in biological environments. It presents, in fact, a very low toxicity, Zn2+/Mg2+ selectivity and a very large fluorescence enhancement on complexation.