Pyrene interaction with selected heavy metal ions in aqueous sodium dodecyl sulphate (SDS)

Abstract

Pyrene interaction with Fe3+, Cu2+, Cr3+, Ni2+, Pb2+ was studied in 0.02 mol L-1 SDS. All the studied heavy metal ions quenched the fluorescence intensity of pyrene though variations were found in the level of quenching. Stern-Volmer equation fitted the pyrene quenching by heavy metal ions. Stern-Volmer constants (KSV) were obtained with the fitting of the quenching data with the Stern-Volmer equation. KSV shows the level of quenching and the sensitivity of the method. Greater the KSV larger will be the detection and quantification limit and vice versa. KSV, detection limit (DL) and quantification limit (QL) varied from 9.26 × 103 mol L-1 to 4.13 × 103 mol L-1, 1.61 × 10-6 mol L-1 to 5.85 × 10-6 mol L-1 and 5.38 × 10-6 mol L-1 to 19.49 × 10-6 mol L-1 respectively. The overall sensitivity, DL and QL were observed in the order Fe3+ > Cu2+ > Cr3+ > Ni2+ > Pb2+. Pyrene fluorescence quenching by the studied heavy metal ions is a fruitful method for their determination in environmental samples.