Sensitive and selective SERS probe for Hg(II) detection using aminated ring-close structure of Rhodamine6G

A sensitive surface–enhanced Raman scattering (SERS) probe for selective detection of Hg(II) was designed and prepared by incorporating the well-known Rhodamine 6G and ethylenediamine into one molecule which is a aminated ring-close structure of Rhodamine 6G (R-NH2). Due to the presence of oxygen and nitrogen functional groups of R-NH2, Hg(II) would combined with two R-NH2 molecules. The probe molecule R-NH2 displays a highly selectively response of SERS enhancement towards 1 nM Hg(II) and featured SERS response with a broad pH span. The results establish the well-fitted linearity function of the SERS intensity with the concentration of Hg(II) in aqueous solution, suggesting the possibility for real-time detection of Hg(II) and the convenience for potential application.