Optical sensors cross-sensitivity amendment: The case study of heavy metals CSPT detection

5,10,15,20-Tetraferrocenyl porphyrin (PFc4) and coumarin-based thia-aza macrocycle ligand (L3) were studied for the development of cross-sensitive optical chemical sensors aimed to the determination of transition metal ions. The ligands oppositely vary their fluorimetric response: PFc4 fluorescence is quenched upon the several transition metal ions concentration growth, while the fluorescence of L3 increases upon mercury ions exposure. By the simultaneous incorporation of both ligands in the same membrane, a series of cross-sensitive materials were obtained and tested for transition metal ions detection by CSPT method.