Fluorophore-assisted green fabrication of flexible and cost-effective Ag nanoparticles decorated PVA nanofibers for SERS based trace detection

Abstract

Detection and particularly quantitative analysis of organic pollutants such as rhodamine 6G (R6G), and p-nitrophenol (pNP) in water are very important for both human health and the ecological environment. In this study, we synthesized as a facile and low cost method silver nanoparticles on poly(vinyl alcohol) (PVA) nanofibers to prepare a film based surface enhancement Raman scattering (SERS) substrate for label free molecular detection. Detection of the R6G molecule with the obtained SERS substrate is possible even at concentrations as low as 10−12 M and therefore the obtained SERS substrate indicated excellent molecular sensitivity for R6G molecule. Limit of detection value (LOD) was determined as 1.07 × 10−13 M while the enhancement factor (EF) of the obtained SERS substrate was calculated as 1.06 × 109 for the R6G molecule. A fluorophore molecule named as 2,5-bis(4-hydroxyphenyl)thiazolo[5,4-d]thiazole (HPhTT) was effectively used for cross-linking of PVA nanofibers to use them as growth template for silver nanoparticles (AgNPs) formation on the surface without any reducing and stabilizing agent thanks to unique properties of HPhTT. Green and one pot preparation of such SERS substrates can pave the way for easily prepared commercial substrates.Moreover, AgNPs decorated PVA nanofiber-based SERS substrate has high reproducibility and good stability for SERS detection of organic pollutants. Obtained SERS substrate is expected to be applicable as a label-free sensor for various chemical and biological molecules.