Silver Nanoparticles with Enhanced Fluorescence Effects on Fluorescein Derivative

Silver nanoparticles were prepared by sodium borohydride reduction method for analyzing metal-enhanced fluorescence property. Some variables including the dosage of reagent, reacting temperature and pH value had been investigated. Subsequently, a comparison of metal-enhanced fluorescence efficiency was made between two kinds of fluorescent dyes, namely fluorescein and 6-carboxyfluorescein at different silver concentrations. The experimental results show that the fluorescence of both dyes are remarkably enhanced. It is interesting to note that the increase of emission intensity is stronger than that of their corresponding excitation ones. Furthermore, a 5.038-fold increase in fluorescence for 6-carboxyfluorescein while a 2.506-fold increase for fluorescein are observed. This may attribute to the interaction between dyes and silver nanoparticels.