title: Interactions between Antibiotics and Graphene-Based Materials in Water: A Comparative Experimental and Theoretical Investigation.
abstract: Complex interactions between antibiotics and graphene-based materials determine both the adsorption performance of graphene-based materials and the transport behaviors of antibiotics in water. In this work, such interactions were investigated through adsorption experiments, instrumental analyses and theoretical DFT calculations. Three typical antibiotics (norfloxacin (NOR), sulfadiazine (SDZ) and tetracycline (TC)) and different graphene-based materials (divided into two groups: graphene oxides-based ones (GOs) and reduced GOs (RGOs)) were employed. Optimal adsorption pHs for NOR, SDZ, and TC are 6.2, 4.0, and 4.0, respectively. At corresponding optimal pHs, NOR favored RGOs (adsorption capability: ∼50 mg/g) while SDZ preferred GOs (∼17 mg/g); All adsorbents exhibited similar uptake of TC (∼70 mg/g). Similar amounts of edge carboxyls of both GOs and RGOs wielded electrostatic attraction with NOR and TC, but not with SDZ. According to DFT-calculated most-stable-conformations of antibiotics-adsorbents complexes, the intrinsic distinction between GOs and RGOs was the different amounts of sp(2) and sp(3) hybridization regions: π-π electron donor-acceptor effect of antibiotic-sp(2)/sp(3) and H-bonds of antibiotic-sp(3) coexisted. Binding energy (BE) of the former was larger for NOR; the latter interaction was stronger for SDZ; two species of TC at the optimal pH, i.e., TC(+) and TC(0), possessed larger BE with sp(3) and sp(2) regions, respectively.
authors.affiliation: School of Chemistry and Materials Science, Jiangsu Provincial Key Laboratory of Material Cycling and Pollution Control, Nanjing Normal University , Nanjing 210023, PR China.
authors.forename: Xuntong
authors.initials: X
authors.lastname: Zhang
authors.affiliation: School of Chemistry and Materials Science, Jiangsu Provincial Key Laboratory of Material Cycling and Pollution Control, Nanjing Normal University , Nanjing 210023, PR China.
authors.forename: Jiachun
authors.initials: J
authors.lastname: Shen
authors.affiliation: School of Chemistry and Materials Science, Jiangsu Provincial Key Laboratory of Material Cycling and Pollution Control, Nanjing Normal University , Nanjing 210023, PR China.
authors.forename: Ning
authors.initials: N
authors.lastname: Zhuo
authors.affiliation: Department of Chemistry, University of California , Riverside, California 92521, United States.
authors.forename: Ziqi
authors.initials: Z
authors.lastname: Tian
authors.affiliation: School of Chemistry and Materials Science, Jiangsu Provincial Key Laboratory of Material Cycling and Pollution Control, Nanjing Normal University , Nanjing 210023, PR China.
authors.forename: Peiran
authors.initials: P
authors.lastname: Xu
authors.affiliation: School of Chemistry and Materials Science, Jiangsu Provincial Key Laboratory of Material Cycling and Pollution Control, Nanjing Normal University , Nanjing 210023, PR China.
authors.forename: Zhen
authors.initials: Z
authors.lastname: Yang
authors.affiliation: School of Chemistry and Materials Science, Jiangsu Provincial Key Laboratory of Material Cycling and Pollution Control, Nanjing Normal University , Nanjing 210023, PR China.
authors.forename: Weiben
authors.initials: W
authors.lastname: Yang
keywords: antibiotics; electrostatic attraction; graphene derivatives; hydrogen bond; interactions; π−π electron donor−acceptor effect