Au dotted magnetic graphene sheets for sensitive detection of thiocyanate

Abuse of thiocyanate (SCN-) in food products results in the people's health risks. Detection of SCN-residue in milk and infant formula calls for rapid and sensitive analytical protocols. In this work, Au nanoparticles dotted magnetic sheets (Au-MGS) with the help of inositol hexakisphosphate (IP6) were used as surface enhanced Raman scattering (SERS) substrate for sensitively detecting trace SCN- in milk. Since IP6 served as binding and stable agent to chelate with metal ions, the Au-MGS represented uniformity and stability as well as the well-dispersive Au nanoparticles. As a result, the limit of detection (LOD) reached 10(-8) g/L. Additionally, with aiding by an external magnet inducing, Au-MGS substrate further presented improved SERS activity. By using a portable Raman spectrometer, such Au-MGS based SERS assay could be expected to be used for in situ detection of SCN- in milk on markets as well as for determination of SCN- in saliva from the smoker. (C) 2016 Elsevier B.V. All rights reserved.