Ion inducing surface interaction for improved SERS detection of melamine in fertilizer and soil

Abstract

AbstractUltra‐sensitive platform for surface‐enhanced Raman scattering detecting trace melamine is constructed by adding Fe3+ ions. In this work, first, inositol hexaphosphate (IP6) micelle capped silver nanoparticles (IP6@AgNPs) is synthesized. Taking advantage of the strong interaction of Fe3+ and IP6 micelle, surface‐enhanced Raman scattering activity of IP6@AgNPs could be improved by formation of more “hot spots” induced by rational addition of due amount Fe3+. Second, IP6@AgNPs binding Fe3+ could offer the anchoring sites to capture melamine molecules due to containing NH group and/or N atom. Such Fe3+ acted as dual functions is beneficial to elevating sensitivity of determining trace melamine in water, fertilizer, and soil samples with the limits of detection about 1.26, 1.26, and 63.0 ppb, respectively. This proposed assay based on a portable Raman system could monitor real samples without complicated pretreatment, which is perspective to inspect trace melamine on‐field in water and soil environment.