Influence of bovine hemoglobin on the disruption of fluorescence resonance energy transfer between zinc sulfide quantum dots and fluorescent silica nanoparticles

Herein, the fluorescence resonance energy transfer (FRET) system composed of Zinc sulfide quantum dots (ZnS QDs) and fluorescent silica nanoparticles (FS) and the influence of bovine hemoglobin (BHb) on the systemwere studied using spectroscopy. UV-vis, SEM and XRD were used to characterize ZnS QDs. FT-IR spectroscopy, Zeta potential, DLS and fluorescence spectroscopy confirmed the synthesis of FS. The mechanism and efficiency of FRET in aqueous solution and BHb solution has been analyzed by fluorescence spectroscopy and Forster's nonradiative energy transfer theory, which implied that in the absence of BHb, there is dynamic quenching between ZnS QDs and FS. In the presence of BHb, it is static quenching. And BHb interfered with the stability of the ZnS QDs-FS FRET system and reduced FRET efficiency. Moreover, steady-state, synchronous fluorescence spectra and Raman spectroscopy showed that ZnS QDs caused an increase of hydrophilicity of the chromophore micro-environment, and FS may induce heme degradation to form fluorescent heme product, resulting in increased fluorescence intensity. This investigation will be significant in exploring the toxicity profile of ZnS QDs-FS FRET system for their in vivo. (C) 2021 Elsevier B.V. All rights reserved.

Automated summary

In this study, the FRET system composed of ZnS QDs and FS was investigated using spectroscopy, along with the influence of BHb on the system. The results showed that in the presence of BHb, static quenching occurred, and BHb interfered with the stability of the system, reducing FRET efficiency.