Quenching effect of nickel ions on fluorescent gold nanoparticles

Herein, we reported the quenching effect of Ni2+ on bovine serum albumin protected fluorescent gold nanoparticles (BSA-GNPs). The quenching mechanism was discussed and a static quenching mechanism was proposed. The number of binding sites (n), apparent stability constants (K) and corresponding thermodynamic parameters of BSA-GNPs-Ni2+ complex were measured at different temperatures. Under optimum conditions, the fluorescence intensity of BSA-GNPs is linearly proportional to nickel concentration from 6.0 × 10−8 mol/L to 8.0 × 10−6 mol/L with a detection limit of 1.0 × 10−8 mol/L. The result indicated that BSA-GNP was a potential Ni2+ probe.