SERS Sensing of Metanil Yellow in Turmeric Solution Using Self-Organized Nanoparticle Arrays Grown on Ion Beam Patterned Soda-Lime Glass

Metanil yellow is a potential carcinogen that is commonly used as a food adulterant in turmeric powder. In this study, we detected Metanil Yellow from turmeric powder solution using a Surface Enhanced Raman Spectroscopy (SERS) substrate based on nano patterned soda-lime glass. Low amplitude ripples with an average wavelength around 65 nm was produced on commercially available soda-lime glass using low energy argon ion beam irradiation. Large area SERS templates were produced by growing self-organized ordered Ag nanoparticles on the rippled soda-lime glass. The optical analysis of the produced substrates shows the anisotropic plasmonic response and better Localized Surface Plasmon Resonance (LSPR) activity than Ag nanoparticles grown on rippled Si substrate. A biaxial layer consisting of Lorentz and Drude oscillators describes the real and imaginary parts of the dielectric function. The SERS analysis using Crystal Violet (CV) molecules demonstrates a five-fold improvement in the efficiency of silver grown on glass ripples than silver grown on Si ripples. We have tested the substrate for detecting Metanil yellow up to 10-6 M concentration in the water. Further, using the substrate, up to 10-4 M concentration of Metanil Yellow is detected from the turmeric solution.