title: Facile synthesis of (55)Fe-labeled well-dispersible hematite nanoparticles for bioaccumulation studies in nanotoxicology.
abstract: Although water-dispersible engineered nanoparticles (ENPs) have a wide range of applications, the ENPs used in many nanotoxicological studies tend to form micron-sized aggregates in the exposure media and thus cannot reflect the toxicity of real nanoparticles. Here we described the synthesis of bare hematite nanoparticles (HNPs-0) and two poly(acrylic acid) (PAA)-coated forms (HNPs-1 and HNPs-2). All three HNPs were well dispersed in deionized water, but HNPs-0 quickly aggregated in the three culture media tested. By contrast, the suspensions of HNPs-1 and HNPs-2 remained stable, with negligible amounts of PAA and Fe(3+) liberated from either one under the investigated conditions. To better quantify the accumulation of the coated HNPs, a relatively innocuous (55)Fe-labeled form of HNPs-2 was synthesized as an example and its accumulation in three phytoplankton species was tested. Consistent with the uptake kinetics model for conventional pollutants, the cellular accumulation of HNPs-2 increased linearly with exposure time for two of the three phytoplankton species. These results demonstrate the utility of (55)Fe-labeled well-dispersible HNPs as a model material for nanoparticle bioaccumulation studies in nanotoxicology.
authors.affiliation: State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing, Jiangsu Province, 210023, China.
authors.forename: Bin
authors.initials: B
authors.lastname: Huang
authors.affiliation: State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing, Jiangsu Province, 210023, China.
authors.forename: Lin
authors.initials: L
authors.lastname: Xiao
authors.affiliation: State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing, Jiangsu Province, 210023, China.
authors.forename: Liu-Yan
authors.initials: LY
authors.lastname: Yang
authors.affiliation: State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing, Jiangsu Province, 210023, China.
authors.forename: Rong
authors.initials: R
authors.lastname: Ji
authors.affiliation: State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing, Jiangsu Province, 210023, China. Electronic address: miaoaj@nju.edu.cn.
authors.forename: Ai-Jun
authors.initials: AJ
authors.lastname: Miao
mesh_terms: D000180:Acrylic Resins / Q000737:chemistry*; D055598:Chemical Phenomena; D005290:Ferric Compounds / Q000737:chemistry / Q000378:metabolism / Q000633:toxicity*; D007504:Iron Radioisotopes; D007700:Kinetics; D008962:Models, Theoretical; D053758:Nanoparticles / Q000737:chemistry / Q000378:metabolism / Q000633:toxicity*; D036103:Nanotechnology / Q000379:methods*; D010316:Particle Size; D010839:Phytoplankton / Q000187:drug effects* / Q000378:metabolism; D018675:Toxicity Tests; D014874:Water Pollutants, Chemical / Q000737:chemistry / Q000378:metabolism / Q000633:toxicity*
chemical_list: D000180:Acrylic Resins; D005290:Ferric Compounds; D007504:Iron Radioisotopes; D014874:Water Pollutants, Chemical; C000499:ferric oxide; C006903:carbopol 940
keywords: (55)Fe; Bioaccumulation; Hematite nanoparticles; Poly(acrylic acid); Stability