title: Ultrasensitive sliver nanorods array SERS sensor for mercury ions.
abstract: With years of outrageous mercury emissions, there is an urgent need to develop convenient and sensitive methods for detecting mercury ions in response to increasingly serious mercury pollution in water. In the present work, a portable, ultrasensitive SERS sensor is proposed and utilized for detecting trace mercury ions in water. The SERS sensor is prepared on an excellent sliver nanorods array SERS substrate by immobilizing T-component oligonucleotide probes labeled with dye on the 3'-end and -SH on the 5'-end. The SERS sensor responses to the specific chemical bonding between thymine and mercury ions, which causes the previous flexible single strand of oligonucleotide probe changing into rigid and upright double chain structure. Such change in the structure drives the dyes far away from the excellent SERS substrate and results in a SERS signal attenuation of the dye. Therefore, by monitoring the decay of SERS signal of the dye, mercury ions in water can be detected qualitatively and quantitatively. The experimental results indicate that the proposed optimal SERS sensor owns a linear response with wide detecting range from 1pM to 1μM, and a detection limit of 0.16pM is obtained. In addition, the SERS sensor demonstrates good specificity for Hg2+, which can accurately identify trace mercury ions from a mixture of ten kinds of other ions. The SERS sensor has been further executed to analyze the trace mercury ions in tap water and lake water respectively, and good recovery rates are obtained for sensing both kinds of water. With its high selectivity and good portability, the ultrasensitive SERS sensor is expected to be a promising candidate for discriminating mercury ions in the fields of environmental monitoring and food safety.
authors: Key Lab for Organic Electronics & Information Displays (KLOEID), Institute of Advanced Materials (IAM), Synergetic Innovation Center for Organic Electronics and Information Displays, Nanjing University of Posts & Telecommunications, Nanjing 210023, China.
authors: Chunyuan
authors: C
authors: Song
authors: Key Lab for Organic Electronics & Information Displays (KLOEID), Institute of Advanced Materials (IAM), Synergetic Innovation Center for Organic Electronics and Information Displays, Nanjing University of Posts & Telecommunications, Nanjing 210023, China.
authors: Boyue
authors: B
authors: Yang
authors: Suzhou Institute of Nano-Tech & Nano-Bionics (SINANO), Chinese Academy of Sciences, Suzhou 215123, China. Electronic address: yzhu2011@sinano.ac.cn.
authors: Yu
authors: Y
authors: Zhu
authors: Key Lab for Organic Electronics & Information Displays (KLOEID), Institute of Advanced Materials (IAM), Synergetic Innovation Center for Organic Electronics and Information Displays, Nanjing University of Posts & Telecommunications, Nanjing 210023, China.
authors: Yanjun
authors: Y
authors: Yang
authors: Key Lab for Organic Electronics & Information Displays (KLOEID), Institute of Advanced Materials (IAM), Synergetic Innovation Center for Organic Electronics and Information Displays, Nanjing University of Posts & Telecommunications, Nanjing 210023, China. Electronic address: iamlhwang@njupt.edu.cn.
authors: Lianhui
authors: L
authors: Wang
mesh_terms: D015374:Biosensing Techniques / Q000379:methods; D002413:Cations, Divalent / Q000032:analysis; D060766:Drinking Water / Q000032:analysis*; D004784:Environmental Monitoring / Q000379:methods; D060106:Lakes / Q000032:analysis*; D057230:Limit of Detection; D008628:Mercury / Q000032:analysis*; D043942:Nanotubes / Q000737:chemistry*; D015345:Oligonucleotide Probes / Q000737:chemistry; D012834:Silver / Q000737:chemistry*; D013059:Spectrum Analysis, Raman / Q000379:methods*; D014874:Water Pollutants, Chemical / Q000032:analysis*
chemical_list: D002413:Cations, Divalent; D060766:Drinking Water; D015345:Oligonucleotide Probes; D014874:Water Pollutants, Chemical; D012834:Silver; D008628:Mercury
keywords: Mercury ions; Oligonucleotide; Optical sensor; Sliver nanorods array; Surface-enhanced Raman spectroscopy (SERS)