title: Contribution of coated humic acids calculated through their surface coverage on nano iron oxides for ofloxacin and norfloxacin sorption.
abstract: Sorption of organic contaminants on organo-mineral complexes has been investigated extensively, but the sorption contribution of mineral particles was not properly addressed before calculating KOC, especially for ionic organic contaminants. We measured the surface coverage of a humic acid (HA) on nano iron oxides (n-Fe2O3) in a series of synthesized organo-mineral complexes. The contribution of the coated HA to ofloxacin (OFL) and norfloxacin (NOR) sorption in HA-n-Fe2O3 complexes was over 80% of the total sorption with the surface coverage of 36% and fOC of 1.6%. All the coated HA showed higher sorption to NOR and OFL in comparison to the original HA, suggesting HA fractionation and/or physical re-conformation during organo-mineral complex formation. The decreased KOC with multilayer coating may suggest the importance of site-specific interactions for OFL sorption, while the increased KOC with multilayer coating may suggest the importance of partitioning in hydrophobic region for NOR sorption.
authors.affiliation: Faculty of Environmental Science & Engineering, Kunming University of Science & Technology, Kunming, Yunnan 650500, China.
authors.forename: Hongbo
authors.initials: H
authors.lastname: Peng
authors.affiliation: Faculty of Environmental Science & Engineering, Kunming University of Science & Technology, Kunming, Yunnan 650500, China.
authors.forename: Ni
authors.initials: N
authors.lastname: Liang
authors.affiliation: Faculty of Environmental Science & Engineering, Kunming University of Science & Technology, Kunming, Yunnan 650500, China.
authors.forename: Hao
authors.initials: H
authors.lastname: Li
authors.affiliation: Faculty of Environmental Science & Engineering, Kunming University of Science & Technology, Kunming, Yunnan 650500, China.
authors.forename: Fangyuan
authors.initials: F
authors.lastname: Chen
authors.affiliation: Faculty of Environmental Science & Engineering, Kunming University of Science & Technology, Kunming, Yunnan 650500, China.
authors.forename: Di
authors.initials: D
authors.lastname: Zhang
authors.affiliation: Faculty of Environmental Science & Engineering, Kunming University of Science & Technology, Kunming, Yunnan 650500, China. Electronic address: panbocai@gmail.com.
authors.forename: Bo
authors.initials: B
authors.lastname: Pan
authors.affiliation: Stockbridge School of Agriculture, University of Massachusetts, Amherst, MA 01003, USA.
authors.forename: Baoshan
authors.initials: B
authors.lastname: Xing
mesh_terms: D000327:Adsorption; D000900:Anti-Bacterial Agents / Q000737:chemistry*; D005290:Ferric Compounds / Q000737:chemistry*; D006812:Humic Substances / Q000032:analysis*; D008903:Minerals / Q000737:chemistry; D009643:Norfloxacin / Q000737:chemistry*; D015242:Ofloxacin / Q000737:chemistry*
chemical_list: D000900:Anti-Bacterial Agents; D005290:Ferric Compounds; D006812:Humic Substances; D008903:Minerals; C000499:ferric oxide; D015242:Ofloxacin; D009643:Norfloxacin
keywords: Engineered nanoparticles; Ionic organic contaminants; Mineral particles; Organo-mineral complex; Pharmaceuticals