Dye fluorescence quenching by newly synthesized silver nanoparticles

New types of silver nanoparticles (Ag NPs) were prepared by the reduction of silver trifluoroacetate with diamine-sarcophagine (DiAmsar) in DMF solution. Nanoparticles growth, morphology, and chemical composition were determined by ultraviolet–visible spectroscopy, transmission electron microscopy, and Fourier transform infrared spectroscopy, respectively. The effect of prepared Ag NPs on the fluorescence quenching of the dyes rhodamine 6G and 4-hydroxycoumarin were investigated in different temperatures. The results of the quenching experiments were analyzed using Stern–Volmer equation. The Stern–Volmer constant values showed that the quenching efficiencies decreased as the temperature increases indicating that the quenching process was a dynamic-type quenching. Moreover, the energy transfer behavior between Ag NPs and dye molecules were interrogated using Förster/fluorescence resonance energy transfer and nanomaterial surface energy transfer models. The anti-bacterial activities of Ag NPs were assessed against the Staphylococcus aureus and Escherichia coli bacteria. Results showed that the entitled Ag NPs have excellent antibacterial properties.