title: SERS detection and removal of mercury(II)/silver(I) using oligonucleotide-functionalized core/shell magnetic silica sphere@Au nanoparticles.
abstract: Heavy metal ions, such as Hg(2+) and Ag(+), pose severe risks in human health and the environment. For sensitive detection and selective removal of Hg(2+) and Ag(+) ions, here, we demonstrate a surface-enhanced Raman scattering (SERS)-active platform by employing the oligonucleotide-functionalized magnetic silica sphere (MSS)@Au nanoparticles (NPs). This system exploits mismatched T-Hg-T and C-Ag-C bridges to capture Hg(2+) and Ag(+) ions, exhibiting excellent responses for Hg(2+) ions in the range of 0.1-1000 nM and for Ag(+) in the range of 10-1000 nM. The assay is highly selective for the target ions and does not respond to other metal ions. Additionally, the Hg(2+) and Ag(+) ions in this system can be effectively removed from surrounding solutions by an external magnetic field or through spontaneous precipitation. Moreover, more than 80% of the MSS@Au NPs can be easily recycled with the help of cysteine. We anticipate that the designed strategy could be extended to other analytes that can bind to DNA molecules with a high affinity, and can be used in many potential applications such as environmental renovation, toxin detection, and groundwater analysis.
authors.affiliation: Advanced Photonics Center, Southeast University , 2# Sipai Lou, Nanjing 210096, Jiangsu China.
authors.forename: Min
authors.initials: M
authors.lastname: Liu
authors.forename: Zhuyuan
authors.initials: Z
authors.lastname: Wang
authors.forename: Shenfei
authors.initials: S
authors.lastname: Zong
authors.forename: Hui
authors.initials: H
authors.lastname: Chen
authors.forename: Dan
authors.initials: D
authors.lastname: Zhu
authors.forename: Lei
authors.initials: L
authors.lastname: Wu
authors.forename: Guohua
authors.initials: G
authors.lastname: Hu
authors.forename: Yiping
authors.initials: Y
authors.lastname: Cui
mesh_terms: D011232:Chemical Precipitation; D006046:Gold / Q000737:chemistry; D007477:Ions / Q000737:chemistry; D060526:Magnetic Fields; D008628:Mercury / Q000032:analysis* / Q000302:isolation & purification; D053768:Metal Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D009841:Oligonucleotides / Q000737:chemistry*; D012822:Silicon Dioxide / Q000737:chemistry; D012834:Silver / Q000032:analysis* / Q000302:isolation & purification; D013059:Spectrum Analysis, Raman
chemical_list: D007477:Ions; D009841:Oligonucleotides; D012834:Silver; D006046:Gold; D012822:Silicon Dioxide; D008628:Mercury