title: Influence of biofilm on the transport of fullerene (C60) nanoparticles in porous media.
abstract: The significance of biofilm on fullerene C(60) nanoparticles transport and deposition were examined both in porous media and quartz crystal microbalance with dissipation (QCM-D) systems under a variety of environmentally relevant ionic strength (1-25 mM in NaCl and 0.1-5 mM in CaCl(2)) and flow conditions (4-8 m day(-1)). The magnitudes of deposition rate coefficients (k(d)) were compared between porous media with and without biofilm extracellular polymeric substances (EPS) coating under equivalent fluid velocities and solution chemistries. The observed k(d) were greater in porous media with biofilm EPS coating relative to those without biofilm EPS coating across the entire solution ionic strengths and fluid velocities examined, demonstrating that the enhancement of C(60) deposition by the biofilm EPS coating is relevant to a wide range of environmental conditions. This greater deposition was also observed on silica surfaces with biofilm EPS coating in QCM-D system. The results clearly showed that biofilm EPS have a great influence on C(60) deposition. Derjaguin-Landau-Verwey-Overbeek (DLVO) theory could not explain the enhanced C(60) deposition by biofilm EPS. Biochemical and physical characteristics of biofilm EPS were responsible for the increased C(60) deposition.
authors.affiliation: The Key Laboratory of Water and Sediment Sciences, Ministry of Education, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, PR China. tongmeiping@iee.pku.edu.cn
authors.forename: Meiping
authors.initials: M
authors.lastname: Tong
authors.forename: Jiali
authors.initials: J
authors.lastname: Ding
authors.forename: Yun
authors.initials: Y
authors.lastname: Shen
authors.forename: Pingting
authors.initials: P
authors.lastname: Zhu
mesh_terms: D018441:Biofilms / Q000254:growth & development*; D004785:Environmental Pollutants / Q000737:chemistry*; D004926:Escherichia coli / Q000737:chemistry; D005374:Filtration / Q000379:methods*; D037741:Fullerenes / Q000032:analysis / Q000737:chemistry*; D007700:Kinetics; D009994:Osmolar Concentration; D016062:Porosity; D011791:Quartz / Q000737:chemistry*
chemical_list: D004785:Environmental Pollutants; D037741:Fullerenes; D011791:Quartz