Selective fluorescence sensors for Cu and Hg ions using acridinium-polymer complexes.

The photophysical properties of two acridinium derivatives, 9-phenyl-10-methylacridinium (Ph-Arc) and 9-mesityl-10-methyl acridinium (Mes-Acr) were investigated in aqueous solutions of poly(methacrylic acids) (PMAA) at various pH values with various polymer to dye (R/D) ratios. In acidic conditions, PMAA effectively turned on the emission of both acridinium derivatives. Micromolar concentrations of copper (II) ions can selectively turn off the emission of dye/PMAA mixtures with a linear response range from 0.