title: New surface-enhanced Raman spectroscopy substrates via self-assembly of silver nanoparticles for perchlorate detection in water.
abstract: Perchlorate (ClO4-) has recently emerged as a widespread contaminant in drinking water and groundwater supplies in the United States, and a need exists for rapid detection and monitoring of this contaminant. In this study, surface-enhanced Raman spectroscopy (SERS) was studied as a means of ClO4- detection, and new sol-gel-based SERS substrates were developed by self-assembly of silver colloidal nanoparticles with various functionalized silane reagents. These substrate materials were tailored to allow detection of ClO4- in water with improved sorptivity, stability, and sensitivity and with the ability to detect ClO4- at concentrations as low as 10(-6) M (or 100 microg/L) with good reproducibility. Similar techniques were used to fabricate capillary SERS flow cells by assembling functionalized silver nanoparticles capable of attracting ClO4- to the SERS surface or the internal wall of glass capillaries. These capillary flow cells could be readily configured to allow for in situ, nondestructive detection of ClO4- via fiber optics.
authors.affiliation: Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA. wangw@ornl.gov
authors.forename: Wei
authors.initials: W
authors.lastname: Wang
authors.forename: Baohua
authors.initials: B
authors.lastname: Gu
mesh_terms: D003460:Crystallization / Q000379:methods; D004784:Environmental Monitoring / Q000379:methods; D043942:Nanotubes / Q000032:analysis / Q000737:chemistry* / Q000648:ultrastructure; D010316:Particle Size; D010472:Perchlorates / Q000032:analysis* / Q000737:chemistry*; D012834:Silver / Q000032:analysis / Q000737:chemistry*; D013059:Spectrum Analysis, Raman / Q000379:methods*; D013499:Surface Properties; D014867:Water / Q000032:analysis*; D014874:Water Pollutants, Chemical / Q000032:analysis*
chemical_list: D010472:Perchlorates; D014874:Water Pollutants, Chemical; D014867:Water; D012834:Silver; C494474:perchlorate