title: Surface-enhanced Raman spectroscopy for uranium detection and analysis in environmental samples.
abstract: Techniques for rapid screening of uranium in environmental samples are needed, and this study entails the development of surface-enhanced Raman scattering (SERS) for analyzing uranium in aqueous media with improved sensitivity and reproducibility. A new SERS substrate based on (aminomethyl)phosphonic acid (APA)-modified gold nanoparticles was found to give greater than three orders of magnitude SERS enhancement compared with unmodified bare gold nanoparticles. Intensities of uranyl band at about 830 cm(-1) were proportional to the concentrations of uranium in solution, especially at relatively low concentrations (<10(-5) M). A detection limit of approximately 8x10(-7) M was achieved with a good reproducibility since the measurement was performed directly in dispersed aqueous suspension. Without pretreatment, the technique was successfully employed for detecting uranium in a highly contaminated groundwater with a low pH, high dissolved salts (e.g., nitrate, sulfate, calcium and aluminum) and total organic carbon.
authors.affiliation: Oak Ridge Institute for Science and Education, Oak Ridge, TN 37831, United States.
authors.forename: Chuanmin
authors.initials: C
authors.lastname: Ruan
authors.forename: Wensui
authors.initials: W
authors.lastname: Luo
authors.forename: Wei
authors.initials: W
authors.lastname: Wang
authors.forename: Baohua
authors.initials: B
authors.lastname: Gu
mesh_terms: D005618:Fresh Water / Q000737:chemistry*; D006046:Gold / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D053768:Metal Nanoparticles / Q000737:chemistry; D015394:Molecular Structure; D009943:Organophosphorus Compounds / Q000737:chemistry; D015203:Reproducibility of Results; D013059:Spectrum Analysis, Raman / Q000379:methods*; D014501:Uranium / Q000032:analysis*; D014874:Water Pollutants, Chemical / Q000032:analysis*
chemical_list: D009943:Organophosphorus Compounds; D014874:Water Pollutants, Chemical; C036423:1-aminomethylphosphonic acid; D014501:Uranium; D006046:Gold