Ag@SiO nanoparticles performing as a nanoprobe for selective analysis of 2-aminoanthracene in wastewater samples via metal-enhanced fluorescence.

Due to severely overlapping emission and or/ excitation spectra of polycyclic aromatic hydrocarbons (PAHs), the specifically recognizing PAHs by the fluorescent technique is still a challenge. Here, synthesized Ag@SiO nanoparticles with 40 ± 4 nm Ag core and 7 ± 1 nm SiO shell performing as a nanoprobe could selectively recognize 2-aminoanthracene (2-AA) via metal-enhanced fluorescence (MEF) within 2 min. The sensing mechanism was based on the facts: (1) there was a perfect spectral overlap between the local surface plasmon resonance (LSPR) peak of Ag@SiO and the absorptive peak of 2-AA, and (2) 2-AA could interact with Ag@SiO nanoparticles through hydrogen bonds between -NH in 2-AA and -OH in SiO shell. As a result, with Ag@SiO nanoparticles as a nanoprobe, a fluorescent assay for detecting 2-AA was developed with a linear range from 1 nM to 800 nM, which exhibited an excellent selectivity over possible PAHs, dyes and metal ions. The detection limit was 1 nM. Finally, the developed assay was applied to analyse 2-AA in industrial wastewater samples, which were highly consistent with that of high performance liquid chromatography (HPLC). This study presents a feasible assay for detecting 2-AA for environmental monitoring and toxic evaluating.