A fluorescent probe for zinc ions based on N-methyltetraphenylporphine with high selectivity

N-Methyl-α,β,γ,δ-tetraphenylporphine (NMTPPH) has been used to detect trace amount of zinc ions in ethanol-water solution by fluorescence spectroscopy. The fluorescent probe undergoes a fluorescent emission intensity enhancement upon binding to zinc ions in EtOH/H2O (1:1, v/v) solution. The fluorescence enhancement of NMTPPH is attributed to the 1:1 complex formation between NMTPPH and Zn(II) which has been utilized as the basis for the selective detection of Zn(II). The linear response range covers a concentration range of Zn(II) from 5.0 × 10−7 to 1.0 × 10−5 mol/L and the detection limit is 1.5 × 10−7 mol/L. The fluorescent probe exhibits high selectivity over other common metal ions except for Cu(II).