Fluorescence enhancement of fluorescently labelled substance by Ag nanoparticles embedded in silicate glass substrates

Abstract

The glass substrates containing metal Ag nanoparticles (NPs) were fabricated by electric field assisted ion diffusion process. Two luminescent substances, NaYF₄:Er³⁺/Yb³⁺ and CdSe, were deposited on the substrates respectively, and their luminescent properties were studied. The results showed that compared with Ag NPs coated on the surface of the substrates, the stability of Ag NPs was significantly enhanced and also that Ag NPs embedded in the substrates produced higher luminescent enhancement for different fluorescent substances. Seven- and threefold fluorescence enhancements were achieved for up-conversion luminescence of Er³⁺/Yb³⁺ codoped NaYF₄ and down-conversion luminescence of CdSe quantum dots (QDs) respectively. Moreover, it was indicated that introduction of Ag NPs into glass substrate by electric field assisted ion diffusion process improved sensitivity of CdSe QDs for Cu²⁺ detection. Therefore, the electric field assisted ion diffusion process would be a promising method for the fabrication of more stable metal Ag NPs in the glass substrates used for surface plasmon enhanced luminescence.

Keywords:

• Fluorescence enhancement
• Silver nanoparticles
• Electric field assisted ion diffusion
• Fluorescently labelled substance

We are grateful to the preresearching fund (grant no. 9140A02040111DZ3301) and opening measuring fund (grant no. 2012028) of Tongji University and Shanghai Science and Technology Commission research projects (project no. 12nm0504700) for the financial support. The research work was also supported by Key Laboratory of Materials for High Power Laser, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy and Sciences.