A new bifunctional fluorescent sensor based on naphthalimide-functionalized silica nanoparticles for detection and adsorption of Cu2+ in aqueous solution

A new bifunctional fluorescent sensor for Cu2+ based on naphthalimide-functionalized silica nanoparticles (NF-SiO2) was designed and synthesized. NF-SiO2 exhibits excellent fluorescence sensitivity and selectivity towards Cu2+ over other metal ions in aqueous media, and it also shows a good adsorption capacity for Cu2+. Moreover, the detection limit of NF-SiO2 for Cu2+ is 1.5 × 10−7 M (S/N = 3) and it can be easily recovered by treatment of a solution of EDTA. These results indicate that this fluorescent sensor may find potential and favorable applications for simple detection and efficient removal of Cu2+ in toxicological and environmental fields.