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Akbari Alavijeh M, Schindler M, Wirth MG, Qafoku O, Kovarik L, Perea DE. Nanoscale characterization of the sequestration and transformation of silver and arsenic in soil organic matter using atom probe tomography and transmission electron microscopy. ENVIRONMENTAL SCIENCE. PROCESSES & IMPACTS 2023; 25:577-593. [PMID: 36727412 DOI: 10.1039/d2em00332e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
This study investigates the sequestration and transformation of silver (Ag) and arsenic (As) ions in soil organic matter (OM) at the nanoscale using the combination of atom probe tomography (APT), transmission electron microscopy (TEM), focused ion beam (FIB), ion mill thinning and scanning electron microscopy (SEM). Silver-arsenic contaminated organic-rich soils were collected along the shore of Cobalt Lake, a former mining and milling site of the famous Ag deposits at Cobalt, Ontario, Canada. SEM examinations show that particulate organic matter (OM grains) contains mineral inclusions composed of mainly Fe, S, and Si with minor As and traces of Ag. Four OM grains with detectable concentrations of Ag (by SEM-EDS) were further characterized with either a combination of TEM and APT or TEM alone. These examinations show that As is predominantly sequestered by OM through either co-precipitation with Fe-(hydr)oxide inclusions or adsorption on Fe-(hydr)oxides and their subsequent transformation into scorodite (FeAsO4·2H2O)/amorphous Fe-arsenate (AFA). Silver nanoparticles (NPs) with diameters in the range of ∼5-20 nm occur in the organic matrix as well as on the surface of Fe-rich inclusions (Fe-hydroxides, Fe-arsenates, Fe-sulfides), whereas Ag sulfide NPs were only observed on the surfaces of the Fe-rich inclusions. Rims of Ag-sulfides on Ag NPs (TEM data), accumulation of S atoms within and around Ag NPs (APT data), and the occurrence of dendritic as well as euhedral acanthite NPs with diameters in the range of ∼100-400 nm (TEM data) indicate that the sulfidation of the Ag NPs occurred via a mineral-replacement reaction (rims) or a complete dissolution of the Ag NPs, the subsequent precipitation of acanthite NPs and their aggregation (dendrites) and Ostwald ripening (euhedral crystals). These results show the importance of OM and, specifically the mineral inclusions in the sequestration of Ag and As to less bioavailable forms such as acanthite and scorodite, respectively.
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Affiliation(s)
| | - Michael Schindler
- Department of Earth Sciences, University of Manitoba, Winnipeg, MB R3T 2N2, Canada.
| | - Mark G Wirth
- Environmental Molecular Sciences Laboratory (EMSL), Pacific Northwest National Laboratory, Richland, WA 99354, USA
| | - Odeta Qafoku
- Environmental Molecular Sciences Laboratory (EMSL), Pacific Northwest National Laboratory, Richland, WA 99354, USA
| | - Libor Kovarik
- Physical and Computational Sciences Directorate, Pacific Northwest National Laboratory, Richland, WA 99354, USA
| | - Daniel E Perea
- Environmental Molecular Sciences Laboratory (EMSL), Pacific Northwest National Laboratory, Richland, WA 99354, USA
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Alarcon R, Walter M, Paez M, Azócar MI. Ostwald Ripening and Antibacterial Activity of Silver Nanoparticles Capped by Anti-Inflammatory Ligands. NANOMATERIALS (BASEL, SWITZERLAND) 2023; 13:428. [PMID: 36770389 PMCID: PMC9920692 DOI: 10.3390/nano13030428] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/29/2022] [Revised: 01/13/2023] [Accepted: 01/17/2023] [Indexed: 06/18/2023]
Abstract
Silver nanoparticles (AgNPs) have been extensively studied during recent decades as antimicrobial agents. However, their stability and antibacterial activity over time have yet to be sufficiently studied. In this work, AgNPs were coated with different stabilizers (naproxen and diclofenac and 5-chlorosalicylic acid) in different concentrations. The suspensions of nanostructures were characterized by transmission electron microscopy, UV-Vis and FT-IR spectroscopic techniques. The antibacterial activity as a function of time was determined through microbiological studies against Staphylococcus aureus. The AgNPs show differences in stabilities when changing the coating agent and its concentration. This fact could be a consequence of the difference in the nature of the interaction between the stabilizer and the surface of the NPs, which were evaluated by FT-IR spectroscopy. In addition, an increase in the size of the nanoparticles was observed after 30 days, which could be related to an Ostwald maturation phenomenon. This result raises new questions about the role that stabilizers play on the surface of NPs, promoting size change in NPs. It is highly probable that the stabilizer functions as a growth controller of the NPs, thus determining an effect on their biological properties. Finally, the antibacterial activity was evaluated over time against the bacterium Staphylococcus aureus. The results showed that the protective or stabilizing agents can play an important role in the antibacterial capacity, the control of the size of the AgNPs and additionally in the stability over time.
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Affiliation(s)
| | | | | | - Manuel Ignacio Azócar
- Departamento de Quimica de los Materiales, Facultad de Quimica y Biologia, & SMAT-C, Universidad de Santiago de Chile, Av. Bernardo O’Higgins 3363, Estacion Central, Santiago 8990000, Chile
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3
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Duncan TV, Bajaj A, Sharma A, Gray PJ, Weiner RG, Pillai KV. Sulfides mediate the migration of nanoparticle mass out of nanocomposite plastics and into aqueous environments. NANOIMPACT 2022; 28:100426. [PMID: 36096361 DOI: 10.1016/j.impact.2022.100426] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/06/2022] [Revised: 09/02/2022] [Accepted: 09/05/2022] [Indexed: 05/26/2023]
Abstract
We show that inorganic sulfides strongly influence transfer (migration) of nanoparticle mass out of polymer nanocomposites (PNCs) and into aqueous environments. We first manufactured two families of PNCs: one incorporating silver nanoparticles (AgNPs) and one incorporating CdSe quantum dots (QDs). Then, we assessed migration out of these PNCs and into aqueous media containing Na2S at concentrations ranging from 0 to 10-4 M. Results show that Na2S strongly suppressed migration of Ag from AgNP-based PNCs: the migration into water spiked with 10-6 M Na2S was 79% less than migration into water without Na2S, and no migration was detected (LOD ≈ 0.01 ng/cm2) in water spiked with Na2S at 10-5 M or 10-4 M. With CdSe QD-based PNCs, Na2S suppressed Cd migration but enhanced Se migration, resulting in only a small net effect on the total QD migration but a large shift of the leachate composition (from favoring Cd by an average of 5.8 to 1 in pure water to favoring Se 9.4 to 1 when Na2S was present at 10-4 M). These results show that common inorganic substances like sulfides may play a strong role in determining the environmental fate of polymer-dispersed nanoparticles and imply that migration tests conducted in purified water may not always accurately reflect migration into real environments.
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Affiliation(s)
- Timothy V Duncan
- Center for Food Safety and Applied Nutrition, US Food and Drug Administration, Bedford Park, IL 60501, USA.
| | - Akhil Bajaj
- Department of Food Science and Nutrition, Illinois Institute of Technology, Bedford Park, IL 60501, USA
| | - Ashutosh Sharma
- Department of Food Science and Nutrition, Illinois Institute of Technology, Bedford Park, IL 60501, USA
| | - Patrick J Gray
- Center for Food Safety and Applied Nutrition, US Food and Drug Administration, Bedford Park, IL 60501, USA
| | - Rebecca G Weiner
- Center for Food Safety and Applied Nutrition, US Food and Drug Administration, Bedford Park, IL 60501, USA
| | - Karthik V Pillai
- Center for Food Safety and Applied Nutrition, US Food and Drug Administration, Bedford Park, IL 60501, USA
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4
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Baalousha M, Sikder M, Poulin BA, Tfaily MM, Hess NJ. Natural organic matter composition and nanomaterial surface coating determine the nature of platinum nanomaterial-natural organic matter corona. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 806:150477. [PMID: 34563904 DOI: 10.1016/j.scitotenv.2021.150477] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/11/2021] [Revised: 09/15/2021] [Accepted: 09/16/2021] [Indexed: 06/13/2023]
Abstract
Natural organic matter corona (NOM corona) is an interfacial area between nanomaterials (NMs) and the surrounding environment, which gives rise to NMs' unique surface identity. While the importance of the formation of natural organic matter (NOM) corona on engineered nanomaterials (NMs) to NM behavior, fate, and toxicity has been well-established, the understanding of how NOM molecular properties affect NOM corona composition remains elusive due to the complexity and heterogeneity of NOM. This is further complicated by the variation of NOMs from different origins. Here we use eight NOM isolates of different molecular composition and ultrahigh resolution Fourier-transform ion cyclotron resonance-mass spectrometry (ESI-FT-ICR-MS) to determine the molecular composition of platinum NM-NOM corona as a function of NOM composition and NM surface coating. We observed that the composition of PtNM-NOM corona varied with the composition of the original NOM. The percentage of NOM formulas that formed PVP-PtNM-NOM corona was higher than those formed citrate-PtNM-NOM corona, due to increased sorption of NOM formulas, in particular condensed hydrocarbons, to the PVP coating. The relative abundance of heteroatom formulas (CHON, CHOS, and CHOP) was higher in the PVP-PtNM-NOM corona than in citrate-PtNM-corona which was in turn higher than those in the original NOM isolate, indicating preferential partitioning of heteroatom-rich molecules to NM surfaces. The relative abundance of CHO, CHON, CHOS, CHOP and condensed hydrocarbons in PtNM-NOM corona increased with their increase in NOM isolates. Furthermore, PtNM-NOM corona is rich with compounds with high molecular weight. This study demonstrates that the composition and properties of PtNM-NOM corona depend on NOM molecular properties and PtNM surface coating. The results here provide evidence of molecular interactions between NOM and NMs, which are critical to understanding NM colloidal properties (e.g., surface charge and stability), interaction forces (e.g., van der Waals and hydrophobic), environmental behaviors (e.g., aggregation, dissolution, sulfidation, etc.), and biological effects (e.g., uptake, bioaccumulation, and toxicity).
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Affiliation(s)
- Mohammed Baalousha
- South Carolina SmartState Center for Environmental Nanoscience and Risk (CENR), Department of Environmental Health Sciences, University of South Carolina, Columbia, SC 29208, USA.
| | - Mithun Sikder
- South Carolina SmartState Center for Environmental Nanoscience and Risk (CENR), Department of Environmental Health Sciences, University of South Carolina, Columbia, SC 29208, USA
| | - Brett A Poulin
- U. S. Geological Survey, Boulder, CO 80303, USA; Department of Environmental Toxicology, University of California Davis, Davis, CA 95616, USA
| | - Malak M Tfaily
- Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, Richland, WA 99354, USA; Department of Environmental Science, University of Arizona, AZ, USA 85721
| | - Nancy J Hess
- Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, Richland, WA 99354, USA
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Bathi JR, Moazeni F, Upadhyayula VKK, Chowdhury I, Palchoudhury S, Potts GE, Gadhamshetty V. Behavior of engineered nanoparticles in aquatic environmental samples: Current status and challenges. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 793:148560. [PMID: 34328971 DOI: 10.1016/j.scitotenv.2021.148560] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/08/2020] [Revised: 06/14/2021] [Accepted: 06/16/2021] [Indexed: 06/13/2023]
Abstract
The increasing use of engineered nanoparticles (ENPs) in consumer products has led to their increased presence in natural water systems. Here, we present a critical overview of the studies that analyzed the fate and transport behavior of ENPs using real environmental samples. We focused on cerium dioxide, titanium dioxide, silver, carbon nanotubes, and zinc oxide, the widely used ENPs in consumer products. Under field scale settings, the transformation rates of ENPs and subsequently their physicochemical properties (e.g., toxicity and bioavailability) are primarily influenced by the modes of interactions among ENPs and natural organic matter. Other typical parameters include factors related to water chemistry, hydrodynamics, and surface and electronic properties of ENPs. Overall, future nanomanufacturing processes should fully consider the health, safety, and environmental impacts without compromising the functionality of consumer products.
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Affiliation(s)
- Jejal Reddy Bathi
- 615 McCallie Ave, Civil and Chemical Engineering, University of Tennessee at Chattanooga, TN 37403, United States.
| | - Faegheh Moazeni
- W256K Olmsted Building, School of Science Engineering and Technology, Penn State Harrisburg University, PA 17057, United States
| | | | - Indranil Chowdhury
- PACCAR 346, Civil and Environmental Engineering, Washington State University, Pullman, WA, United States
| | - Soubantika Palchoudhury
- 615 McCallie Ave, Civil and Chemical Engineering, University of Tennessee at Chattanooga, TN 37403, United States
| | - Gretchen E Potts
- 615 McCallie Ave, Department of Chemistry and Physics, University of Tennessee at Chattanooga, TN 37403, United States
| | - Venkataramana Gadhamshetty
- 501 E. St Joseph Street, Civil and Environmental Engineering, South Dakota School of Mines and Technology, SD 57701, United States; 2-Dimensional Materials for Biofilm Engineering Science and Technology (2DBEST) Center, South Dakota School of Mines and Technology, 501 E. St. Joseph Street, Rapid City, SD 57701, United States
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6
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Zhao J, Wang X, Hoang SA, Bolan NS, Kirkham MB, Liu J, Xia X, Li Y. Silver nanoparticles in aquatic sediments: Occurrence, chemical transformations, toxicity, and analytical methods. JOURNAL OF HAZARDOUS MATERIALS 2021; 418:126368. [PMID: 34329024 DOI: 10.1016/j.jhazmat.2021.126368] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Revised: 06/02/2021] [Accepted: 06/07/2021] [Indexed: 06/13/2023]
Abstract
Sediments represent the major sink for released silver nanoparticles (AgNPs) in aquatic environments. It is well known that the environmental behavior and toxicity of AgNPs in sediments are governed by their specific chemical species instead of their total concentration. This review focuses on various chemical transformations of AgNPs in sediments, which have not been well outlined before. We first outline the concentrations of AgNPs in sediments. The predicted concentrations are 1-5 µg kg-1 in most model studies. Once enter sediments, AgNPs are transformed to different species (e.g., Ag2S, Ag-humic substance complexes, AgCl, and Ag+) during multiple chemical transformations, such as oxidative dissolution, sulfidation, chlorination, and complexation. Those chemical behaviors mitigate the toxicity of AgNPs by reducing their availability and decreasing Ag+ release. Benthic invertebrates and microbes are prone to be affected by AgNPs. AgNPs are found to be accumulated in sediment-dwelling organisms and transferred to higher trophic levels along the food web. Besides X-ray absorption spectroscopy, reliable separation procedures coupled with detection techniques, are powerful tools that characterize the speciation of AgNPs in sediments. More research is needed to investigate diverse chemical transformations in various sediments through development of novel techniques and mathematical models.
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Affiliation(s)
- Jian Zhao
- Key Laboratory of Water and Sediment Sciences of Ministry of Education, State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing 100875, People's Republic of China
| | - Xinjie Wang
- Key Laboratory of Water and Sediment Sciences of Ministry of Education, State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing 100875, People's Republic of China
| | - Son A Hoang
- Global Centre for Environmental Remediation, University of Newcastle, Callaghan, NSW 2308, Australia; Division of Urban Infrastructural Engineering, Mien Trung University of Civil Engineering, Phu Yen 56000, Viet Nam
| | - Nanthi S Bolan
- Global Centre for Environmental Remediation, University of Newcastle, Callaghan, NSW 2308, Australia; School of Agriculture and Environment, The University of Western Australia, Perth, WA 6001, Australia; The UWA Institute of Agriculture, The University of Western Australia, Perth, WA 6001, Australia
| | - M B Kirkham
- Department of Agronomy, Throckmorton Plant Sciences Center, Kansas State University, Manhattan, KS 66506, United States
| | - Jingnan Liu
- Key Laboratory of Water and Sediment Sciences of Ministry of Education, State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing 100875, People's Republic of China
| | - Xinghui Xia
- Key Laboratory of Water and Sediment Sciences of Ministry of Education, State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing 100875, People's Republic of China
| | - Yang Li
- Key Laboratory of Water and Sediment Sciences of Ministry of Education, State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing 100875, People's Republic of China.
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7
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Thwala M, Klaine S, Musee N. Exposure Media and Nanoparticle Size Influence on the Fate, Bioaccumulation, and Toxicity of Silver Nanoparticles to Higher Plant Salvinia minima. Molecules 2021; 26:molecules26082305. [PMID: 33923373 PMCID: PMC8071571 DOI: 10.3390/molecules26082305] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2021] [Revised: 04/04/2021] [Accepted: 04/06/2021] [Indexed: 12/16/2022] Open
Abstract
Silver nanoparticles (AgNPs) are favoured antibacterial agents in nano-enabled products and can be released into water resources where they potentially elicit adverse effects. Herein, interactions of 10 and 40 nm AgNPs (10-AgNPs and 40-AgNPs) with aquatic higher plant Salvinia minima at 600 µg/L in moderately hard water (MHW), MHW of raised calcium (Ca2+), and MHW containing natural organic matter (NOM) were examined. The exposure media variants altered the AgNPs’ surface properties, causing size-dependent agglomeration. The bio-accessibility in the ascending order was: NOM < MHW < Ca2+, was higher in plants exposed to 10-AgNPs, and across all exposures, accumulation was higher in roots compared to fronds. The AgNPs reduced plant growth and the production of chlorophyll pigments a and b; the toxic effects were influenced by exposure media chemistry, and the smaller 10-AgNPs were commonly the most toxic relative to 40-AgNPs. The toxicity pattern was linked to the averagely higher dissolution of 10-AgNPs compared to the larger counterparts. The scanning electron microscopy and X-ray fluorescence analytical techniques were found limited in examining the interaction of the plants with AgNPs at the low exposure concentration used in this study, thus challenging their applicability considering the even lower predicted environmental concentrations AgNPs.
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Affiliation(s)
- Melusi Thwala
- Water Centre, Council for Scientific and Industrial Research, Pretoria 0001, South Africa;
- Zoology Department, University of Johannesburg, Auckland Park 2006, South Africa
- Department of Environmental Health, Nelson Mandela University, Port Elizabeth 6031, South Africa
- Centre for Environmental Management, University of the Free State, Bloemfontein 9300, South Africa
| | - Stephen Klaine
- Department of Biological Sciences, Clemson University, Clemson, SC 29634, USA;
| | - Ndeke Musee
- Emerging Contaminants Ecological and Risk Assessment (ECERA) Research Group, Department of Chemical Engineering, University of Pretoria, Pretoria 0001, South Africa
- Correspondence: or
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Natarajan L, Jenifer MA, Mukherjee A. Eco-corona formation on the nanomaterials in the aquatic systems lessens their toxic impact: A comprehensive review. ENVIRONMENTAL RESEARCH 2021; 194:110669. [PMID: 33359698 DOI: 10.1016/j.envres.2020.110669] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Revised: 12/18/2020] [Accepted: 12/21/2020] [Indexed: 06/12/2023]
Abstract
Recent studies have shown that nanosized materials including plastics as a major cause of concern in the aquatic ecosystem. Fortunately, in the aquatic environment, the surface of the materials is often colonized by exudates of aquatic microorganisms (biofilm), where these materials are attached and surrounded by a secreted matrix with a sticky layer. The significance of these biofilms on the existence and beneficial implications of these pollutants has been studied in recent decades. Here we develop the concept of these pollutants as a complex matrix of polymers to which Extracellular Polymeric Substances (EPS) binds to form eco-corona modifying its density and surface charge of these particles. This review critically integrates the outstanding properties and functions of algal EPS in the aquatic environment and their dynamic interactions of early colonization on the surface of these pollutants, the impact of biofilm formation on stability, reactivity and, toxicity from the current literature. Due to the modifications of the environmental processes, EPS can have an impact on the toxicity thus special attention is focused on their behavior to decrease the toxicity of the pollutants in the aquatic environment. Although there has been an increasing number of researches in this area, further progress is needed to explore the extent to which ecological processes could be impacted, including the modifications in the behavior of aquatic pollutants. Thus, this review provides a recent perspective into the mechanisms of how eco-corona formation mitigates the toxicity of nanomaterials prevalent in aquatic ecosystems.
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Affiliation(s)
- Lokeshwari Natarajan
- School of Biosciences and Technology, VIT University, Vellore, India; Centre for Nanobiotechnology, VIT, Vellore, Tamil Nadu, India
| | - M Annie Jenifer
- School of Agricultural Innovations and Advanced Learning, VIT, Vellore, Tamil Nadu, India.
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Zhu H, Dong Y, Zhang P, Hu X, Zhang H, Zhao H, Wang E, Jin Y, Yang X. Silver transfer based plasmonic nanoprobe for highly sensitive detection of hydrogen sulfide. Microchem J 2020. [DOI: 10.1016/j.microc.2020.105526] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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10
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Shaghaghi M, Rashtbari S, Abdollahi A, Dehghan G, Jouyban A. A Sensitive, Simple and Direct Determination of Pantoprazole Based on a "Turn off-on" Fluorescence Nanosensor by Using Terbium-1,10-phenanthroline-silver Nanoparticles. ANAL SCI 2020; 36:1345-1352. [PMID: 33177314 DOI: 10.2116/analsci.20p142] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
A new sensitive, simple, rapid, reliable and selective fluorometric method for the determination of pantoprazole (PAN) in human plasma and a pharmaceutical formulation has been developed. This technique is based on a quenching effect of silver nanoparticles (AgNPs) on the emission intensity of a fluorescent probe, terbium(III)-1,10-phenantroline (Tb(III)-phen) complex (due to a fluorescence resonance energy transfer (FRET) phenomenon between the Tb(III)-phen complex and AgNPs), and then restoring the fluorescence intensity of the Tb(III)-phen-AgNPs system upon the addition of PAN (turn off-on process). The effects of various factors on the proposed method including time, temperature, pH, order of the addition of various reagents and the concentration of AgNPs were investigated. Under the optimal conditions, a good linear relationship between the enhanced emission intensity of the Tb(III)-phen-AgNPs system and the PAN concentration was observed in the range of (10 - 1000) × 10-8 M. The limit of detection (LOD) and the limit of quantitation (LOQ) were 7.2 × 10-8 and 24.2 × 10-8 M, respectively. Also, the interferences of some common interfering species on the fluorescence intensity of the system were investigated. This simple and sensitive method was successfully applied for the determination of PAN in spiked human plasma samples and in its capsule formulation. The analytical recoveries were in the range of 88.54 - 101.33 and 90.07 - 98.85%, respectively.
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Affiliation(s)
| | - Samaneh Rashtbari
- Department of Biology, Faculty of Natural Sciences, University of Tabriz
| | | | - Gholamreza Dehghan
- Department of Biology, Faculty of Natural Sciences, University of Tabriz
| | - Abolghasem Jouyban
- Pharmaceutical Analysis Research Center and Faculty of Pharmacy, Tabriz University of Medical Sciences, Tabriz, IranandDigestive Diseases Research Institute, Tehran University of Medical Sciences
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11
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Aqueous Dilution of Noble NPs Bulk Dispersions: Modeling Instability due to Dissolution by AF4 and Stablishing Considerations for Plasmonic Assays. NANOMATERIALS 2020; 10:nano10091802. [PMID: 32927649 PMCID: PMC7560132 DOI: 10.3390/nano10091802] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/16/2020] [Revised: 09/02/2020] [Accepted: 09/07/2020] [Indexed: 12/25/2022]
Abstract
Among different nanomaterials, gold and silver nanoparticles (AuNPs and AgNPs) have become useful tools for a wide variety of applications in general, and particularly for plasmonic assays. Particle size and stability analysis are key elements for their practical applications since the NPs properties depend on these parameters. Hence, in the present work, asymmetrical flow field flow fractionation (AF4) coupled to UV-Vis and dynamic light scattering (DLS) detectors in series, has been evaluated for stability studies of citrate-capped AuNPs and AgNPs aqueous dispersions. First, experimental parameters, such as mobile phase or cross-flow rate were optimized. Sodium azide to pH 7 for AuNPs and pH 9.2 for AgNPs were selected as the optimum mobile phase. The analytical response of bulk dispersions of AuNPs (20, 40, 60 and 80 nm) and AgNPs (20, 40 and 60 nm) and their dilutions have been studied. Fractograms showed a decrease on the absorbance signal in diluted dispersions as a function of time and particle size for the diluted dispersions that can be explained by dissolution in diluted dispersion since hydrodynamic diameter was constant. The results indicated that the dependence of the signal with time was more intense for AgNPs than for AuNPs, which can be correlated with its lower stability. These findings should be considered when plasmonic assays are realized. Here, assays involving non-oxidant acidic acids as use cases, were tested for several batches of NPs and considerations about their stability and operability stablished.
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12
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Lieb HC, Nguyen BD, Ramsayer ER, Mullaugh KM. A voltammetric investigation of the sulfidation of silver nanoparticles by zinc sulfide. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 720:137685. [PMID: 32325601 DOI: 10.1016/j.scitotenv.2020.137685] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2019] [Revised: 02/10/2020] [Accepted: 03/01/2020] [Indexed: 06/11/2023]
Abstract
Silver nanoparticles (Ag NPs) are among the most common forms of nanoparticles in consumer products, yet the environmental implications of their widespread use remain unclear due to uncertainties about their fate. Because sulfidation of Ag NPs results in the formation of a stable silver sulfide (Ag2S) product, it is likely an important removal mechanism of bioavailable silver in natural waters. In addition to sulfide, the complete conversion of Ag NPs to Ag2S will require dissolved oxygen or some other oxidant so dispersed metal sulfides may be an important pool of reactive sulfide for such reactions in oxygenated systems. The reaction of Ag NPs with zinc sulfide (ZnS) was investigated using a voltammetric method, anodic stripping voltammetry (ASV). ASV provided sensitive, in situ measurements of the release of zinc (Zn2+) cations resulting from the cation exchange reaction between Ag NPs and ZnS. The effects of Ag NP size and surface coatings on the initial rates of sulfidation by ZnS were examined. Sulfidation of smaller Ag NPs generally occurred faster and to a greater extent due to their larger relative surface areas. Sulfidation of Ag NPs capped by citrate and lipoic acid occurred more rapidly relative to polyvinylpyrrolidone (PVP) and branched polyethylene (BPEI). This study demonstrates the utility of voltammetry for such investigations and provides insights into important factors controlling Ag NP sulfidation such as availability of dissolved oxygen, Ag NP size and Ag NP surface coating. Furthermore, this work demonstrates the importance of cation exchange reactions between silver and metal sulfides, and how the environmental release of Ag NPs could alter the speciation of other metals of environmental significance.
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Affiliation(s)
- Heather C Lieb
- Department of Chemistry & Biochemistry, 66 George St., College of Charleston, Charleston, SC, USA
| | - Bach D Nguyen
- Department of Chemistry & Biochemistry, 66 George St., College of Charleston, Charleston, SC, USA
| | - Emily R Ramsayer
- Department of Chemistry & Biochemistry, 66 George St., College of Charleston, Charleston, SC, USA
| | - Katherine M Mullaugh
- Department of Chemistry & Biochemistry, 66 George St., College of Charleston, Charleston, SC, USA.
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13
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Courtois P, Rorat A, Lemiere S, Guyoneaud R, Attard E, Levard C, Vandenbulcke F. Ecotoxicology of silver nanoparticles and their derivatives introduced in soil with or without sewage sludge: A review of effects on microorganisms, plants and animals. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2019; 253:578-598. [PMID: 31330350 DOI: 10.1016/j.envpol.2019.07.053] [Citation(s) in RCA: 55] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/26/2019] [Revised: 07/09/2019] [Accepted: 07/10/2019] [Indexed: 06/10/2023]
Abstract
Silver nanoparticles (AgNPs) are widely incorporated in many products, partly due to their antimicrobial properties. The subsequent discharge of this form of silver into wastewater leads to an accumulation of silver species (AgNPs and derivatives resulting from their chemical transformation), in sewage sludge. As a result of the land application of sewage sludge for agricultural or remediation purposes, soils are the primary receiver media of silver contamination. Research on the long-term impact of AgNPs on the environment is ongoing, and this paper is the first review that summarizes the existing state of scientific knowledge on the potential impact of silver species introduced into the soil via sewage sludge, from microorganisms to earthworms and plants. Silver species can easily enter cells through biological membranes and affect the physiology of organisms, resulting in toxic effects. In soils, exposure to AgNPs may change microbial biomass and diversity, decrease plant growth and inhibit soil invertebrate reproduction. Physiological, biochemical and molecular effects have been documented in various soil organisms and microorganisms. Negative effects on organisms of the dominant form of silver in sewage sludge, silver sulfide (Ag2S), have been observed, although these effects are attenuated compared to the effects of metallic AgNPs. However, silver toxicity is complex to evaluate and much remains unknown about the ecotoxicology of silver species in soils, especially with respect to the possibility of transfer along the trophic chain via accumulation in plant and animal tissues. Critical points related to the hazards associated with the presence of silver species in the environment are described, and important issues concerning the ecotoxicity of sewage sludge applied to soil are discussed to highlight gaps in existing scientific knowledge and essential research directions for improving risk assessment.
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Affiliation(s)
- Pauline Courtois
- Univ. Lille - LGCgE - Laboratoire de Génie Civil et géo-Environnement, Cité scientifique, SN3, F-59655, Villeneuve d'Ascq, France
| | - Agnieszka Rorat
- Univ. Lille - LGCgE - Laboratoire de Génie Civil et géo-Environnement, Cité scientifique, SN3, F-59655, Villeneuve d'Ascq, France
| | - Sébastien Lemiere
- Univ. Lille - LGCgE - Laboratoire de Génie Civil et géo-Environnement, Cité scientifique, SN3, F-59655, Villeneuve d'Ascq, France
| | - Rémy Guyoneaud
- Université de Pau et des Pays de l'Adour/E2S/CNRS, Institut des Sciences Analytiques et de Physico-chimie pour L'Environnement et les Matériaux (IPREM), UMR 5254, 64000, Pau, France
| | - Eléonore Attard
- Université de Pau et des Pays de l'Adour/E2S/CNRS, Institut des Sciences Analytiques et de Physico-chimie pour L'Environnement et les Matériaux (IPREM), UMR 5254, 64000, Pau, France
| | - Clément Levard
- Aix Marseille Univ, CNRS, IRD, INRA, Coll France, CEREGE, Aix-en-Provence, France
| | - Franck Vandenbulcke
- Univ. Lille - LGCgE - Laboratoire de Génie Civil et géo-Environnement, Cité scientifique, SN3, F-59655, Villeneuve d'Ascq, France.
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14
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Jornet-Martínez N, Hakobyan L, Argente-García AI, Molins-Legua C, Campíns-Falcó P. Nylon-Supported Plasmonic Assay Based on the Aggregation of Silver Nanoparticles: In Situ Determination of Hydrogen Sulfide-like Compounds in Breath Samples as a Proof of Concept. ACS Sens 2019; 4:2164-2172. [PMID: 31364364 DOI: 10.1021/acssensors.9b01019] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
A procedure for supporting silver nanoparticles (AgNPs) on nylon is proposed. Besides, the membrane has been developed as a solid-phase colorimetric plasmonic sensor for volatile sulfide compounds (VSCs) like H2S, CH3SH, and (CH3)2S. AgNP behavior in the membrane has been studied by UV-vis diffuse reflectance spectrometry, Raman spectrometry, High-resolution transmission electron microscopy (HR-TEM), and Scanning electron microscopy (SEM). The sensor responded by changing its color from yellow in absence of VSCs to several orange/brown colors in the function of VSC concentration as occurs in solution; an increase in the hydrodynamic diameter, estimated by both asymmetrical flow field-flow fractionation (AF4) coupled on line to Dynamic light scattering (DLS) detector and batch DLS, is achieved when sulfide is added to the citrate-capped AgNPs. Diffuse reflectance spectrometry and processed digital images obtained with a smartphone have been used as measurements and several transformations for quantitation are proposed; a linear concentration range of hydrogen sulfide from 150 to 1000 ppbv and a detection limit (LOD) of 45 ppbv were achieved, measuring after 10 min of the sensor exposition to the hydrogen sulfide atmosphere (2 L) for humidity percentages between 50 and 96% and room temperature. Satisfactory results in terms of precision (<10%) and selectivity were obtained. The new sensor reported was stable, sensitive, inexpensive, disposable, safe, and user-friendly. Furthermore, it has successfully been applied to determine VSCs expressed as hydrogen sulfide in breath samples (2 L and 250 mL) as a proof of concept. The limit of detection can be improved by increasing the exposition time, if necessary.
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Affiliation(s)
- Neus Jornet-Martínez
- MINTOTA research group. Departament de Química Analítica, Facultat de Química, Universitat de València, Dr. Moliner 50, 46100 Burjassot, Valencia, Spain
| | - Lusine Hakobyan
- MINTOTA research group. Departament de Química Analítica, Facultat de Química, Universitat de València, Dr. Moliner 50, 46100 Burjassot, Valencia, Spain
| | - Ana Isabel Argente-García
- MINTOTA research group. Departament de Química Analítica, Facultat de Química, Universitat de València, Dr. Moliner 50, 46100 Burjassot, Valencia, Spain
| | - Carmen Molins-Legua
- MINTOTA research group. Departament de Química Analítica, Facultat de Química, Universitat de València, Dr. Moliner 50, 46100 Burjassot, Valencia, Spain
| | - Pilar Campíns-Falcó
- MINTOTA research group. Departament de Química Analítica, Facultat de Química, Universitat de València, Dr. Moliner 50, 46100 Burjassot, Valencia, Spain
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15
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Dehghan G, Shaghaghi M, Alizadeh P. A novel ultrasensitive and non-enzymatic "turn-on-off" fluorescence nanosensor for direct determination of glucose in the serum: As an alternative approach to the other optical and electrochemical methods. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2019; 214:459-468. [PMID: 30807944 DOI: 10.1016/j.saa.2019.02.054] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/25/2018] [Revised: 12/16/2018] [Accepted: 02/16/2019] [Indexed: 06/09/2023]
Abstract
A new, simple, rapid, highly sensitive and selective and non-enzymatic fluorometric method for direct determination of glucose in real samples was developed. The method was based on the inhibition of fluorescence resonance energy transfer (FRET) process between terbium (III)-1, 10-phenanthroline (Tb-phen) complex and silver nanoparticles (AgNPs). Upon the addition of glucose, the quenched FRET-based fluorescence of Tb-phen complex was gradually recovered by glucose via its strong adsorption on the surface of AgNPs and removal of Tb-phen complex from AgNPs surface. Therefore the fluorescence of Tb-phen complex switched to "turn-on" state. Under the optimum conditions, a linear relationship was obtained between the enhanced fluorescence intensity and glucose concentration in the range of (5-900) × 10-8 M with the detection limit of 1.94 × 10-8 M. The proposed sensing system was successfully applied to determine glucose in the spiked normal and diabetic patient serum samples after deproteinization with acetonitrile. Analytical recoveries from treated serum samples were in the range of 99.97-104.80% and 92.14-105.43%, respectively. The common interfering species, such as ascorbic acid, fructose and galactose did not cause interior interference due to unique emission properties of Tb-phen complex probe. Also the interaction of the Tb-phen complex with AgNPs, which led to the fluorescence intensity quenching of the complex, was further examined by FTIR technique. In short, as compared to most of the existing methods, the newly proposed method, provides some advantages and makes it promising for the direct rapid screening of glucose residues of real samples in clinical diagnosis of diabetes, as an alternative approach to the other exiting optical and electrochemical methods.
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Affiliation(s)
- Gholamreza Dehghan
- Department of Biology, Faculty of Natural Sciences, University of Tabriz, Tabriz, Iran.
| | - Masoomeh Shaghaghi
- Department of Chemistry, Payame Noor University, P. O. Box 19395-3697, Tehran, Iran.
| | - Pari Alizadeh
- Department of Biology, Faculty of Natural Sciences, University of Tabriz, Tabriz, Iran
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16
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Size and coating of engineered silver nanoparticles determine their ability to growth-independently inhibit aflatoxin biosynthesis in Aspergillus parasiticus. Appl Microbiol Biotechnol 2019; 103:4623-4632. [PMID: 30997552 DOI: 10.1007/s00253-019-09693-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2018] [Revised: 02/05/2019] [Accepted: 02/09/2019] [Indexed: 12/27/2022]
Abstract
Recent studies from our laboratory indicate that engineered silver nanoparticles can inhibit aflatoxin biosynthesis even at concentrations at which they do not demonstrate antifungal activities on the aflatoxin-producing fungus. Whether such inhibition can be modified by altering the nanoparticles' physical properties remains unclear. In this study, we demonstrate that three differently sized citrated-coated silver nanoparticles denoted here as NP1, NP2, and NP3 (where, sizes of NP1 < NP2 < NP3) inhibit aflatoxin biosynthesis at different effective doses in Aspergillus parasiticus, the plant pathogenic filamentous fungus. Recapping NP2 with polyvinylpyrrolidone coating (denoted here as NP2p) also altered its ability to inhibit aflatoxin production. Dose-response experiments with NP concentrations ranging from 10 to 100 ng mL-1 indicated a non-monotonic relationship between aflatoxin inhibition and NP concentration. The maximum inhibitory concentrations differed between the NP types. NP1 demonstrated maximum inhibition at 25 ng mL-1. Both NP2 and NP3 showed maximum inhibition at 50 ng mL-1, although NP2 resulted in a significantly higher inhibition than NP3. While both NP2 and NP2p demonstrated greater aflatoxin inhibition than NP1 and NP3, NP2p inhibited aflatoxin over a significantly wider concentration range as compared to NP2. Our results, therefore, suggest that nano-fungal interactions can be regulated by altering certain NP physical properties. This concept can be used to design NPs for mycotoxin prevention optimally.
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17
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Fletcher ND, Lieb HC, Mullaugh KM. Stability of silver nanoparticle sulfidation products. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 648:854-860. [PMID: 30138885 DOI: 10.1016/j.scitotenv.2018.08.239] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/03/2018] [Revised: 08/17/2018] [Accepted: 08/18/2018] [Indexed: 06/08/2023]
Abstract
The adoption of silver nanoparticles in consumer goods has raised concerns about the potential environmental harm of their widespread use. We studied chemical transformations that Ag NPs may undergo as they pass through sulfide-rich conditions common in waste water treatment plants (WWTPs), which may limit the release of Ag+ from Ag NPs due to the formation of low-solubility silver sulfide (Ag2S). However, it is uncertain whether sulfidation is complete and if sulfidized Ag NPs continue to release Ag+. To address these uncertainties, we monitored the reaction of Ag NPs with various levels of sulfide with an ion selective electrode and UV/visible spectrophotometry over the course of two months. We characterized the products of the sulfidation reactions with a purge-and-trap acid volatile sulfide (AVS) analysis, which served as a measure of the stability of the sulfidized products because sulfide would be readily lost to oxidation unless it is stabilized as Ag2S. The Ag NP surface plasmon resonance (SPR) absorbance peak was initially diminished and then returned over the course of several days after reaction with limited amounts of sulfide, suggesting a dynamic system that may retain some characteristics of the pristine Ag NPs. However, ICP-MS analysis of sulfidized Ag NP suspensions over a two-month period demonstrates that sulfidation limits the release of Ag+ ions from nanosilver that pass through a WWTP, even when sulfide concentrations are limited relative to silver.
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Affiliation(s)
- Nathaniel D Fletcher
- Department of Chemistry & Biochemistry, 66 George St., College of Charleston, Charleston, SC, USA
| | - Heather C Lieb
- Department of Chemistry & Biochemistry, 66 George St., College of Charleston, Charleston, SC, USA
| | - Katherine M Mullaugh
- Department of Chemistry & Biochemistry, 66 George St., College of Charleston, Charleston, SC, USA.
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18
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Zhang F, Allen AJ, Johnston-Peck AC, Liu J, Pettibone JM. Transformation of engineered nanomaterials through the prism of silver sulfidation. NANOSCALE ADVANCES 2019; 1:241-253. [PMID: 31276100 PMCID: PMC6605090 DOI: 10.1039/c8na00103k] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/24/2018] [Accepted: 08/02/2018] [Indexed: 05/27/2023]
Abstract
Understanding the structure transformation of engineered nanomaterials (ENMs) is a grand measurement challenge, which impacts many aspects of ENMs applications, such as their efficacy, safety, and environmental consequence. To address the significant knowledge gap regarding the fundamental kinetic rate and extent of ENM transformation in the environment, we present a comprehensive and mechanistic structural investigation of the transformation, aggregation, and dissolution behavior of a polyvinylpyrrolidone-coated silver nanoparticle (AgNP) suspension upon sulfidation in moderately reduced hard water with fulvic acid and dissolved Na2S. This reaction is among the most prevalent and industrially and environmentally relevant ENMs transformation. Using ex situ transmission electron microscopy (TEM) and both in situ and ex situ synchrotron-based small angle X-ray scattering (SAXS) and X-ray diffraction (XRD), we find that sulfidation of faceted AgNPs strongly depends on the crystallographic orientation of the facets, with nanometer-scale passivation layers developed on {111} and {100} facets and continuous nucleation and growth on {110} facets. Nanobeam electron diffraction and atomic resolution imaging show Ag and Ag2S domains both possess a high degree of crystalline order, contradicting amorphous structures as previously reported. In situ SAXS/XRD allowed simultaneous determination of the morphological changes and extent of sulfidation of AgNPs. SAXS/XRD results strongly indicate sulfidation follows first-order reaction kinetics without any aggregation. Aided by their size monodispersity, for the first time, using direct, in situ morphology and atomic-structure probes whose results mutually corroborate, we unequivocally determined the sulfidation rate constant of AgNPs under an environmentally relevant condition (~0.013 min-1 for 68 nm diameter AgNPs). A rigorous analysis of the long-term sulfidation product of the AgNPs under different S/Ag ratios using ex situ SAXS/XRD clearly demonstrates that the silver mass in the original AgNP and transformed Ag/Ag2S NP is preserved. This result has important environmental implications, strongly suggesting that Ag+ ions, a known highly effective antimicrobial agent, are not leached into the solution during sulfidation of AgNPs. The combined nondestructive methodology can be extended to unfold the structure transformation pathway and kinetics in a broad range of ENM systems.
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Affiliation(s)
- Fan Zhang
- Materials Measurement Science Division, National Institute of Standards and TechnologyGaithersburgMD 20899USA
| | - Andrew J. Allen
- Materials Measurement Science Division, National Institute of Standards and TechnologyGaithersburgMD 20899USA
| | - Aaron C. Johnston-Peck
- Materials Measurement Science Division, National Institute of Standards and TechnologyGaithersburgMD 20899USA
| | - Jingyu Liu
- Materials Measurement Science Division, National Institute of Standards and TechnologyGaithersburgMD 20899USA
| | - John M. Pettibone
- Materials Measurement Science Division, National Institute of Standards and TechnologyGaithersburgMD 20899USA
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19
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Lead JR, Batley GE, Alvarez PJJ, Croteau MN, Handy RD, McLaughlin MJ, Judy JD, Schirmer K. Nanomaterials in the environment: Behavior, fate, bioavailability, and effects-An updated review. ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY 2018; 37:2029-2063. [PMID: 29633323 DOI: 10.1002/etc.4147] [Citation(s) in RCA: 264] [Impact Index Per Article: 44.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/24/2017] [Revised: 01/14/2018] [Accepted: 03/29/2018] [Indexed: 05/21/2023]
Abstract
The present review covers developments in studies of nanomaterials (NMs) in the environment since our much cited review in 2008. We discuss novel insights into fate and behavior, metrology, transformations, bioavailability, toxicity mechanisms, and environmental impacts, with a focus on terrestrial and aquatic systems. Overall, the findings were that: 1) despite substantial developments, critical gaps remain, in large part due to the lack of analytical, modeling, and field capabilities, and also due to the breadth and complexity of the area; 2) a key knowledge gap is the lack of data on environmental concentrations and dosimetry generally; 3) substantial evidence shows that there are nanospecific effects (different from the effects of both ions and larger particles) on the environment in terms of fate, bioavailability, and toxicity, but this is not consistent for all NMs, species, and relevant processes; 4) a paradigm is emerging that NMs are less toxic than equivalent dissolved materials but more toxic than the corresponding bulk materials; and 5) translation of incompletely understood science into regulation and policy continues to be challenging. There is a developing consensus that NMs may pose a relatively low environmental risk, but because of uncertainty and lack of data in many areas, definitive conclusions cannot be drawn. In addition, this emerging consensus will likely change rapidly with qualitative changes in the technology and increased future discharges. Environ Toxicol Chem 2018;37:2029-2063. © 2018 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals, Inc. on behalf of SETAC.
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Affiliation(s)
- Jamie R Lead
- Center for Environmental Nanoscience and Risk, Department of Environmental Health Sciences, Arnold School of Public Health, University of South Carolina, Columbia, South Carolina, USA
| | - Graeme E Batley
- Centre for Environmental Contaminants Research, CSIRO Land and Water, Kirrawee, New South Wales, Australia
| | - Pedro J J Alvarez
- Department of Civil and Environmental Engineering, Rice University, Houston, Texas, USA
| | | | | | | | - Jonathan D Judy
- Soil and Water Sciences Department, University of Florida, Gainesville, Florida, USA
| | - Kristin Schirmer
- Department of Environmental Toxicology, Swiss Federal Institute of Aquatic Science and Technology, Eawag, Dübendorf, Switzerland
- School of Architecture, Civil and Environmental Engineering, Federal Institute of Technology Lausanne, Lausanne, Switzerland
- Institute of Biogeochemistry and Pollutant Dynamics, Swiss Federal Institute of Technology Zürich, Zürich, Switzerland
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20
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Makselon J, Siebers N, Meier F, Vereecken H, Klumpp E. Role of rain intensity and soil colloids in the retention of surfactant-stabilized silver nanoparticles in soil. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2018; 238:1027-1034. [PMID: 29449114 DOI: 10.1016/j.envpol.2018.02.025] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/06/2017] [Revised: 01/31/2018] [Accepted: 02/07/2018] [Indexed: 06/08/2023]
Abstract
Undisturbed outdoor lysimeters containing arable loamy sand soil were used to examine the influence of either heavy rain events (high frequency of high rain intensity), steady rain (continuous rainfall of low rain intensity), and natural rainfall on the transport and retention of surfactant-stabilized silver nanoparticles (AgNP). In addition, the AgNP-soil associations within the Ap horizon were analyzed by means of particle-size fractionation, asymmetrical flow field-flow fractionation coupled with UV/Vis-detection and inductively coupled plasma mass spectrometer (AF4-UV/Vis-ICP-MS), and transmission electron microscopy coupled to an energy-dispersive X-ray (TEM-EDX) analyzer. The results showed that AgNP breakthrough for all rain events was less than 0.1% of the total AgNP mass applied, highlighting that nearly all AgNP were retained in the soil. Heavy rain treatment and natural rainfall revealed enhanced AgNP transport within the Ap horizon, which was attributed to the high pore water flow velocities and to the mobilization of AgNP-soil colloid associations. Particle-size fractionation of the soil revealed that AgNP were present in each size fraction and therefore indicated strong associations between AgNP and soil. In particular, water-dispersible colloids (WDC) in the size range of 0.45-0.1 μm were found to exhibit high potential for AgNP attachment. The AF4-UV/Vis-ICP-MS and TEM-EDX analyses of the WDC fraction confirmed that AgNP were persistent in soil and associated to soil colloids (mainly composed of Al, Fe, Si, and organic matter). These results confirm the particularly important role of soil colloids in the retention and remobilization of AgNP in soil. Furthermore, AF4-UV/Vis-ICP-MS results indicated the presence of single, homo-aggregated, and small AgNP probably due to dissolution.
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Affiliation(s)
- Joanna Makselon
- Institute Agrosphere (IBG-3), Institute of Bio- and Geosciences, Forschungszentrum Jülich GmbH, Germany.
| | - Nina Siebers
- Institute Agrosphere (IBG-3), Institute of Bio- and Geosciences, Forschungszentrum Jülich GmbH, Germany; Ernst Ruska-Centre (ER-C), Forschungszentrum Jülich GmbH, Germany
| | | | - Harry Vereecken
- Institute Agrosphere (IBG-3), Institute of Bio- and Geosciences, Forschungszentrum Jülich GmbH, Germany
| | - Erwin Klumpp
- Institute Agrosphere (IBG-3), Institute of Bio- and Geosciences, Forschungszentrum Jülich GmbH, Germany
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21
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Afshinnia K, Marrone B, Baalousha M. Potential impact of natural organic ligands on the colloidal stability of silver nanoparticles. THE SCIENCE OF THE TOTAL ENVIRONMENT 2018; 625:1518-1526. [PMID: 29996448 DOI: 10.1016/j.scitotenv.2017.12.299] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/13/2017] [Revised: 12/24/2017] [Accepted: 12/25/2017] [Indexed: 06/08/2023]
Abstract
Interaction of natural organic matter (NOM) with engineered nanoparticles (NPs) determine NP fate, transport, and environmental persistence. However, the effect of NOM chemical composition, structure, and concentration on aggregation kinetics and dissolution behavior of silver nanoparticles (AgNPs) are still poorly understood because of heterogeneity and variability in NOM and AgNP properties. Here, aggregation behavior of citrate-coated silver nanoparticles (cit-AgNPs with a z-average diameter of 18nm) was investigated in the presence of l-cysteine (l-cys) and N-acetyl l-cysteine (NAL-cys) using UV-vis spectroscopy. We also investigated the effect of Suwannee River fulvic acid (SRFA) and a NOM isolated from the Yukon River (YRNOM) on the stability of cit-AgNPs. The dissolution of cit-AgNPs decreased with increased L-cys and NAL-cys concentration from 0 to 10μM. The critical coagulation concentration (CCC) of cit-AgNPs decreased in the presence of l-cys and increased in the presence of NAL-cys. Similarly, l-cys destabilizes cit-AgNPs in the presence of SRFA. The differences in the stability of cit-AgNPs in the presence of l-cys and NAL-cys can be attributed to the differences in the functional groups in these two cysteine molecules. l-cys has both negatively charged carboxylic group and a positively charged amine group, resulting in bridging between different particles. NAL-cys is a derivative of cysteine wherein an acetyl group is attached to the nitrogen atom thus shielding the positive charge on the amine group and therefore eliminating the bridging interaction mechanism. SRFA and YRNOM enhanced the stability of cit-AgNPs and increased the CCC value to higher counter ion concentrations. The concentration of SRFA (1-5mgL-1) did not affect the CCC, whereas the increased concentration of YRNOM increased the CCC of cit-AgNPs to high Na+ concentrations likely due to increased sorption of higher molecular weight compounds on the surface of cit-AgNPs. The outcome of this study suggests the importance of understanding the molecular properties of NOM (e.g. functional groups and molecular weight) in determining cit-AgNP environmental behaviors.
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Affiliation(s)
- Kamelia Afshinnia
- Center for Environmental Nanoscience and Risk, Department of Environmental Health Sciences, Arnold School of Public Health, University South Carolina, Columbia, SC 29208, United States
| | - Brandon Marrone
- Center for Environmental Nanoscience and Risk, Department of Environmental Health Sciences, Arnold School of Public Health, University South Carolina, Columbia, SC 29208, United States
| | - Mohammed Baalousha
- Center for Environmental Nanoscience and Risk, Department of Environmental Health Sciences, Arnold School of Public Health, University South Carolina, Columbia, SC 29208, United States.
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22
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Lasat MM, Chung KF, Lead J, McGrath S, Owen RJ, Rocks S, Unrine J, Zhang J. Advancing the Understanding of Environmental Transformations, Bioavailability and Effects of Nanomaterials, an International US Environmental Protection Agency-UK Environmental Nanoscience Initiative Joint Program. ACTA ACUST UNITED AC 2018; 9:385-404. [PMID: 29910967 PMCID: PMC5998674 DOI: 10.4236/jep.2018.94025] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Nanotechnology has significant economic, health, and environmental benefits, including renewable energy and innovative environmental solutions. Manufactured nanoparticles have been incorporated into new materials and products because of their novel or enhanced properties. These very same properties also have prompted concerns about the potential environmental and human health hazard and risk posed by the manufactured nanomaterials. Appropriate risk management responses require the development of models capable of predicting the environmental and human health effects of the nanomaterials. Development of predictive models has been hampered by a lack of information concerning the environmental fate, behavior and effects of manufactured nanoparticles. The United Kingdom (UK) Environmental Nanoscience Initiative and the United States (US) Environmental Protection Agency have developed an international research program to enhance the knowledgebase and develop risk-predicting models for manufactured nanoparticles. Here we report selected highlights of the program as it sought to maximize the complementary strengths of the transatlantic scientific communities by funding three integrated US-UK consortia to investigate the transformation of these nanoparticles in terrestrial, aquatic, and atmospheric environment. Research results demonstrate there is a functional relationship between the physicochemical properties of environmentally transformed nanomaterials and their effects and that this relationship is amenable to modeling. In addition, the joint transatlantic program has allowed the leveraging of additional funding, promoting transboundary scientific collaboration.
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Affiliation(s)
- Mitch M Lasat
- Office of Research and Development, United States Environmental Protection Agency, Washington DC, USA
| | - Kian Fan Chung
- National Heart and Lung Institute, Imperial College, London, UK
| | - Jamie Lead
- Centre for Environmental Nanoscience and Risk, University of South Carolina, Columbia, USA.,University of Birmingham, Edgbaston, UK
| | | | | | - Sophie Rocks
- Institute for Resilient Futures, Cranfield University, Cranfield, UK
| | - Jason Unrine
- Department of Plant and Soil Sciences, University of Kentucky, Lexington, USA
| | - Junfeng Zhang
- Nicholas School of the Environment, Duke University, Durham, USA
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23
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Sikder M, Lead JR, Chandler GT, Baalousha M. A rapid approach for measuring silver nanoparticle concentration and dissolution in seawater by UV-Vis. THE SCIENCE OF THE TOTAL ENVIRONMENT 2018; 618:597-607. [PMID: 28411867 DOI: 10.1016/j.scitotenv.2017.04.055] [Citation(s) in RCA: 66] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2017] [Revised: 04/06/2017] [Accepted: 04/07/2017] [Indexed: 06/07/2023]
Abstract
Detection and quantification of engineered nanoparticles (NPs) in environmental systems is challenging and requires sophisticated analytical equipment. Furthermore, dissolution is an important environmental transformation process for silver nanoparticles (AgNPs) which affects the size, speciation and concentration of AgNPs in natural water systems. Herein, we present a simple approach for the detection, quantification and measurement of dissolution of PVP-coated AgNPs (PVP-AgNPs) based on monitoring their optical properties (extinction spectra) using UV-vis spectroscopy. The dependence of PVP-AgNPs extinction coefficient (ɛ) and maximum absorbance wavelength (λmax) on NP size was experimentally determined. The concentration, size, and extinction spectra of PVP-AgNPs were characterized during dissolution in 30ppt synthetic seawater. AgNPs concentration was determined as the difference between the total and dissolved Ag concentrations measured by inductively coupled plasma-mass spectroscopy (ICP-MS); extinction spectra of PVP-AgNPs were monitored by UV-vis; and size evolution was monitored by atomic force microscopy (AFM) over a period of 96h. Empirical equations for the dependence of maximum absorbance wavelength (λmax) and extinction coefficient (ɛ) on NP size were derived. These empirical formulas were then used to calculate the size and concentration of PVP-AgNPs, and dissolved Ag concentration released from PVP-AgNPs in synthetic seawater at variable particle concentrations (i.e. 25-1500μgL-1) and in natural seawater at particle concentration of 100μgL-1. These results suggest that UV-vis can be used as an easy and quick approach for detection and quantification (size and concentration) of sterically stabilized PVP-AgNPs from their extinction spectra. This approach can also be used to monitor the release of Ag from PVP-AgNPs and the concurrent NP size change. Finally, in seawater, AgNPs dissolve faster and to a higher extent with the decrease in NP concentration toward environmentally relevant concentrations.
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Affiliation(s)
- Mithun Sikder
- Center for Environmental Nanoscience and Risk, Department of Environmental Health Sciences, Arnold School of Public Health, University South Carolina, Columbia, SC 29208, United States
| | - Jamie R Lead
- Center for Environmental Nanoscience and Risk, Department of Environmental Health Sciences, Arnold School of Public Health, University South Carolina, Columbia, SC 29208, United States
| | - G Thomas Chandler
- Center for Environmental Nanoscience and Risk, Department of Environmental Health Sciences, Arnold School of Public Health, University South Carolina, Columbia, SC 29208, United States
| | - Mohammed Baalousha
- Center for Environmental Nanoscience and Risk, Department of Environmental Health Sciences, Arnold School of Public Health, University South Carolina, Columbia, SC 29208, United States.
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Bundschuh M, Filser J, Lüderwald S, McKee MS, Metreveli G, Schaumann GE, Schulz R, Wagner S. Nanoparticles in the environment: where do we come from, where do we go to? ENVIRONMENTAL SCIENCES EUROPE 2018; 30:6. [PMID: 29456907 PMCID: PMC5803285 DOI: 10.1186/s12302-018-0132-6] [Citation(s) in RCA: 319] [Impact Index Per Article: 53.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/23/2017] [Accepted: 01/15/2018] [Indexed: 05/18/2023]
Abstract
Nanoparticles serve various industrial and domestic purposes which is reflected in their steadily increasing production volume. This economic success comes along with their presence in the environment and the risk of potentially adverse effects in natural systems. Over the last decade, substantial progress regarding the understanding of sources, fate, and effects of nanoparticles has been made. Predictions of environmental concentrations based on modelling approaches could recently be confirmed by measured concentrations in the field. Nonetheless, analytical techniques are, as covered elsewhere, still under development to more efficiently and reliably characterize and quantify nanoparticles, as well as to detect them in complex environmental matrixes. Simultaneously, the effects of nanoparticles on aquatic and terrestrial systems have received increasing attention. While the debate on the relevance of nanoparticle-released metal ions for their toxicity is still ongoing, it is a re-occurring phenomenon that inert nanoparticles are able to interact with biota through physical pathways such as biological surface coating. This among others interferes with the growth and behaviour of exposed organisms. Moreover, co-occurring contaminants interact with nanoparticles. There is multiple evidence suggesting nanoparticles as a sink for organic and inorganic co-contaminants. On the other hand, in the presence of nanoparticles, repeatedly an elevated effect on the test species induced by the co-contaminants has been reported. In this paper, we highlight recent achievements in the field of nano-ecotoxicology in both aquatic and terrestrial systems but also refer to substantial gaps that require further attention in the future.
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Affiliation(s)
- Mirco Bundschuh
- Functional Aquatic Ecotoxicology, Institute for Environmental Sciences, University of Koblenz-Landau, Fortstrasse 7, 76829 Landau, Germany
- Department of Aquatic Sciences and Assessment, Swedish University of Agricultural Sciences, Lennart Hjelms väg 9, 75007 Uppsala, Sweden
| | - Juliane Filser
- FB 02, UFT Center for Environmental Research and Sustainable Technology, University of Bremen, Leobener Str. 6, 28359 Bremen, Germany
| | - Simon Lüderwald
- Ecotoxicology and Environment, Institute for Environmental Sciences, University of Koblenz-Landau, Fortstrasse 7, 76829 Landau, Germany
| | - Moira S. McKee
- FB 02, UFT Center for Environmental Research and Sustainable Technology, University of Bremen, Leobener Str. 6, 28359 Bremen, Germany
| | - George Metreveli
- Environmental and Soil Chemistry, Institute for Environmental Sciences, University of Koblenz-Landau, Fortstrasse 7, 76829 Landau, Germany
| | - Gabriele E. Schaumann
- Environmental and Soil Chemistry, Institute for Environmental Sciences, University of Koblenz-Landau, Fortstrasse 7, 76829 Landau, Germany
| | - Ralf Schulz
- Ecotoxicology and Environment, Institute for Environmental Sciences, University of Koblenz-Landau, Fortstrasse 7, 76829 Landau, Germany
| | - Stephan Wagner
- Department of Analytical Chemistry, Helmholtz Centre for Environmental Research-UfZ, Permoserstrasse 15, 04318 Leipzig, Germany
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Zhang W, Xiao B, Fang T. Chemical transformation of silver nanoparticles in aquatic environments: Mechanism, morphology and toxicity. CHEMOSPHERE 2018; 191:324-334. [PMID: 29045933 DOI: 10.1016/j.chemosphere.2017.10.016] [Citation(s) in RCA: 119] [Impact Index Per Article: 19.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2017] [Revised: 09/16/2017] [Accepted: 10/02/2017] [Indexed: 06/07/2023]
Abstract
Silver nanoparticles (Ag NPs) have been inevitably introduced into ecological environment during their extensive applications in daily human life. Thermodynamically, Ag NPs are unstable and transform into other species under various aqueous conditions. Ag NPs and their transformation products pose potential threats to environment and humans. However, the complex environmental conditions and transformations of Ag NPs complicate their human health and environmental risk assessment. To bridge the knowledge gap, four essential environmental transformations, oxidative dissolution, sulfidation, chlorination and photoreduction, of Ag NPs are reviewed herein. The mechanism, morphology and size change, as well as the toxicity of Ag NPs during these transformations under certain aqueous conditions are detailed. In particular, these environmental transformations have shown strong correlations that are discussed. The transformation, fate, bioavailability, morphology and toxicity of Ag NPs are critical factors and should be considered in a complete human health and environmental risk assessment of Ag NPs. The fluctuation of these factors in the realistic environment is also vital and should be considered.
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Affiliation(s)
- Weicheng Zhang
- Key Laboratory of Ecological Security for Water Source Region of Mid-line of South-to-North Diversion Project of Henan Province, College of Agricultural Engineering, Nanyang Normal University, Nanyang, 473061, China; Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, 430072, China
| | - Bangding Xiao
- Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, 430072, China
| | - Tao Fang
- Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, 430072, China.
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Pettibone JM, Gorham JM, Liu J. Determining surface chemical composition of silver nanoparticles during sulfidation by monitoring the ligand shell. JOURNAL OF NANOPARTICLE RESEARCH : AN INTERDISCIPLINARY FORUM FOR NANOSCALE SCIENCE AND TECHNOLOGY 2018; 20:10.1007/s11051-018-4410-4. [PMID: 31555056 PMCID: PMC6759992 DOI: 10.1007/s11051-018-4410-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/07/2018] [Accepted: 10/30/2018] [Indexed: 05/27/2023]
Abstract
Evaluating the surface and core compositions of transforming nanoparticles (NP) represents a significant measurement challenge but is necessary for predicting performance in applied systems and their toxicity in natural environments. Here, we use X-ray photoelectron spectroscopy (XPS) and attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy to characterize both the surface and core ofpolyvinyl pyrollidone-silver nanoparticles in the presence of two Suwannee River fulvic acid (FA) standards and humic acid (HA) during sulfidation, the predominant transformation pathway in environmental systems. Only by using data from both spectroscopic methods was a clear relationship established between AgNP core composition and FA affinity established, where concomitant loss of FA was observed with Ag2S formation. Using XPS to measure AgNP surface composition, overlapping trends from XPS on FA I desorption from the AgNP surface as function of surface sulfidation were observed with FA II in the ATR-FTIR measurements. The reproducibility of the changing heterogeneous coating as a function of AgNP sulfidation provided a transferable method to determine the extent of Ag sulfidation without further need for the high resolution, high cost measurement tools that underpinned validation of the method. The relationship was not observed for HA, where a lower affinity to the AgNP surface was observed, suggesting distinct binding to the NP.
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Affiliation(s)
- John M Pettibone
- Material Measurement Science Division, National Institute of Standards and Technology, Gaithersburg, MD, USA
| | - Justin M Gorham
- Material Measurement Science Division, National Institute of Standards and Technology, Gaithersburg, MD, USA
| | - Jingyu Liu
- Material Measurement Science Division, National Institute of Standards and Technology, Gaithersburg, MD, USA
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Ellis LJA, Baalousha M, Valsami-Jones E, Lead JR. Seasonal variability of natural water chemistry affects the fate and behaviour of silver nanoparticles. CHEMOSPHERE 2018; 191:616-625. [PMID: 29073569 DOI: 10.1016/j.chemosphere.2017.10.006] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/09/2017] [Revised: 09/19/2017] [Accepted: 10/01/2017] [Indexed: 06/07/2023]
Abstract
Understanding the environmental behaviour of nanoparticles (NPs) after release into aquatic systems is essential to predict the environmental implications of nanotechnology. Silver nanoparticles (AgNPs) represent a major class of engineered NPs with a significant potential for environmental impact. Therefore, investigating their transformations in natural waters will help predict their long term environmental fate and behaviour. AgNPs were characterized in natural lake water collected seasonally from the same freshwater source, using column microcosms to assess their behaviour and transport at different depths. Building on our previous work using similar systems with synthetic waters, the influence of water chemistry and NP surface modifications on colloidal stability and dissolution in natural lake water over time was investigated. A simple sedimentation-diffusion model parameterized by the particle properties and total Ag concentration was successfully used to understand AgNPs transport behaviour. PVP coated AgNPs remained colloidally stable, with their transport in the water column dominated by diffusion, and exhibited no significant or substantial changes in data or model parameters for different seasons. Citrate coated AgNPs were susceptible to rapid aggregation, sedimentation, dissolution and reprecipitation; their transport in the water column was determined by both diffusion and sedimentation.
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Affiliation(s)
- Laura-Jayne A Ellis
- School of Geography, Earth and Environmental Sciences, University of Birmingham, Edgbaston, Birmingham, B15 2TT, UK
| | - Mohammed Baalousha
- Center for Environmental Nanoscience and Risk (CENR), Department of Environmental Health Sciences, Arnold School of Public Health, University of South Carolina, Columbia, 29208, USA.
| | - Eugenia Valsami-Jones
- School of Geography, Earth and Environmental Sciences, University of Birmingham, Edgbaston, Birmingham, B15 2TT, UK
| | - Jamie R Lead
- School of Geography, Earth and Environmental Sciences, University of Birmingham, Edgbaston, Birmingham, B15 2TT, UK; Center for Environmental Nanoscience and Risk (CENR), Department of Environmental Health Sciences, Arnold School of Public Health, University of South Carolina, Columbia, 29208, USA.
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28
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Jesmer AH, Velicogna JR, Schwertfeger DM, Scroggins RP, Princz JI. The toxicity of silver to soil organisms exposed to silver nanoparticles and silver nitrate in biosolids-amended field soil. ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY 2017; 36:2756-2765. [PMID: 28440581 DOI: 10.1002/etc.3834] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/04/2016] [Revised: 09/04/2016] [Accepted: 04/21/2017] [Indexed: 06/07/2023]
Abstract
The use of engineered silver nanoparticles (AgNPs) is widespread, with expected release to the terrestrial environment through the application of biosolids onto agricultural lands. The toxicity of AgNPs and silver nitrate (AgNO3 ; as ionic Ag+ ) to plant (Elymus lanceolatus and Trifolium pratense) and soil invertebrate (Eisenia andrei and Folsomia candida) species was assessed using Ag-amended biosolids applied to a natural sandy loam soil. Bioavailable Ag+ in soil samples was estimated using an ion-exchange technique applied to KNO3 soil extracts, whereas exposure to dispersible AgNPs was verified by single-particle inductively coupled plasma-mass spectrometry and transmission electron microscopy-energy dispersive X-ray spectroscopy analysis. Greater toxicity to plant growth and earthworm reproduction was observed in AgNP exposures relative to those of AgNO3 , whereas no difference in toxicity was observed for F. candida reproduction. Transformation products in the AgNP-biosolids exposures resulted in larger pools of extractable Ag+ than those from AgNO3 -biosolids exposures, at similar total Ag soil concentrations. The results of the present study reveal intrinsic differences in the behavior and bioavailability of the 2 different forms of Ag within the biosolids-soils pathway. The present study demonstrates how analytical methods that target biologically relevant fractions can be used to advance the understanding of AgNP behavior and toxicity in terrestrial environments. Environ Toxicol Chem 2017;36:2756-2765. © 2017 Crown in the Right of Canada. Published Wiley Periodicals Inc., on behalf of SETAC.
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Affiliation(s)
- Alexander H Jesmer
- Biological Assessment and Standardization Section, Environment and Climate Change Canada, Ottawa, Ontario, Canada
| | - Jessica R Velicogna
- Biological Assessment and Standardization Section, Environment and Climate Change Canada, Ottawa, Ontario, Canada
| | - Dina M Schwertfeger
- Biological Assessment and Standardization Section, Environment and Climate Change Canada, Ottawa, Ontario, Canada
| | - Richard P Scroggins
- Biological Assessment and Standardization Section, Environment and Climate Change Canada, Ottawa, Ontario, Canada
| | - Juliska I Princz
- Biological Assessment and Standardization Section, Environment and Climate Change Canada, Ottawa, Ontario, Canada
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29
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Schlich K, Hoppe M, Kraas M, Fries E, Hund-Rinke K. Ecotoxicity and fate of a silver nanomaterial in an outdoor lysimeter study. ECOTOXICOLOGY (LONDON, ENGLAND) 2017; 26:738-751. [PMID: 28547324 PMCID: PMC5496968 DOI: 10.1007/s10646-017-1805-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 04/05/2017] [Indexed: 05/07/2023]
Abstract
Sewage sludge is repeatedly applied as fertilizer on farmland due to its high nutrient content. This may lead to a significant increase of silver nanomaterials (AgNM) in soil over years. Therefore, our aim was to investigate the ecotoxicity and fate of AgNM under environmentally relevant conditions in outdoor lysimeters over 25 months. Two AgNM concentrations (1.7 and 8.0 mg/kg dry matter soil) were applied via sewage sludge into soil. In subsamples of the soil, incubated under laboratory conditions for 180 days, the comparability of outdoor and laboratory results regarding ecotoxicity was determined. The results from our long term lysimeter experiments show no detectable horizontal displacement in combination with very low remobilization to the percolate water. Thus, indicate that the sludge applied AgNM remains nearly immobile in the pathway between soils and leachate. However, Ag uptake to the roots of wheat and canola suggests that the chemical conditions in the rhizosphere induce AgNM remobilization from the incorporated sewage sludge even after two harvesting cycles. At the higher AgNM concentration a steady inhibition of the soil microflora was observed over 25 month in the lysimeter study, while there was no effect at the lower AgNM concentration. The results of the laboratory experiment reflect the findings of the lysimeter study and indicate that a risk assessment for AgNM based on data from laboratory tests is acceptable.
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Affiliation(s)
- Karsten Schlich
- Fraunhofer Institute for Molecular Biology and Applied Ecology, Auf dem Aberg 1, Schmallenberg, 57392 Germany
| | - Martin Hoppe
- Federal Institute for Geosciences and Natural Resources, Stilleweg 2, Hannover, 30655 Germany
| | - Marco Kraas
- Fraunhofer Institute for Molecular Biology and Applied Ecology, Auf dem Aberg 1, Schmallenberg, 57392 Germany
| | - Elke Fries
- Federal Institute for Geosciences and Natural Resources, Stilleweg 2, Hannover, 30655 Germany
| | - Kerstin Hund-Rinke
- Fraunhofer Institute for Molecular Biology and Applied Ecology, Auf dem Aberg 1, Schmallenberg, 57392 Germany
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30
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Merrifield RC, Arkill KP, Palmer RE, Lead JR. A High Resolution Study of Dynamic Changes of Ce 2O 3 and CeO 2 Nanoparticles in Complex Environmental Media. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2017; 51:8010-8016. [PMID: 28618231 DOI: 10.1021/acs.est.7b01130] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Ceria nanoparticles (NPs) rapidly and easily cycle between Ce(III) and Ce(IV) oxidation states, making them prime candidates for commercial and other applications. Increased commercial use has resulted in increased discharge to the environment and increased associated risk. Once in complex media such as environmental waters or toxicology exposure media, the same redox transformations can occur, causing altered behavior and effects compared to the pristine NPs. This study used high resolution scanning transmission electron microscopy and electron energy loss spectroscopy to investigate changes in structure and oxidation state of small, polymer-coated ceria suspensions in complex media. NPs initially in either the III or IV oxidation states, but otherwise identical, were used. Ce(IV) NPs were changed to mixed (III, IV) NPs at high ionic strengths, while the presence of natural organic macromolecules (NOM) stabilized the oxidation state and increased crystallinity. The Ce(III) NPs remained as Ce(III) at high ionic strengths, but were modified by the presence of NOM, causing reduced crystallinity and degradation of the NPs. Subtle changes to NP properties upon addition to environmental or ecotoxicology media suggest that there may be small but important effects on fate and effects of NPs compared to their pristine form.
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Affiliation(s)
- Ruth C Merrifield
- Department of Geography, Earth and Environmental Sciences, University of Birmingham , Birmingham, U.K
- Center for Environmental Nanoscience and Risk, University of South Carolina , Columbia, South Carolina United States
| | - Kenton P Arkill
- School of Medicine, University of Nottingham , Nottingham, U.K
- CSIC UPV/EHU and PiE, University of the Basque Country , Lejona, Spain
| | - Richard E Palmer
- Nanoscale Physics Research Laboratory, Physics and Astronomy, University of Birmingham , Birmingham, U.K
| | - Jamie R Lead
- Department of Geography, Earth and Environmental Sciences, University of Birmingham , Birmingham, U.K
- Center for Environmental Nanoscience and Risk, University of South Carolina , Columbia, South Carolina United States
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31
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Milne CJ, Lapworth DJ, Gooddy DC, Elgy CN, Valsami-Jones É. Role of Humic Acid in the Stability of Ag Nanoparticles in Suboxic Conditions. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2017; 51:6063-6070. [PMID: 28436657 DOI: 10.1021/acs.est.6b06054] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Stability and temporal changes in size distributions have been observed for citrate- (cit) and polyvinylpyrrolidone- (PVP) capped silver nanoparticles (AgNPs), in the presence or absence of sulfide and natural organic matter (NOM, as humic acid), while under suboxic conditions. There were substantial differences in the influence of the two capping agents, with PVP-AgNPs showing few or no significant changes in apparent stability or particle size distribution under the conditions examined, while the apparent size distributions of citrate-capped AgNPs changed rapidly. Sulfide and humic acid each individually caused immediate increases in cit-AgNP size distributions, which were then relatively stable over 60-145 days. This may be due to sulfide bridging and cation bridging, respectively. However, in competition, it was the influence of the humic acid that dominated that of the sulfide. These observations have implications for environmental fate and toxicity of AgNP. The increased stability in the presence of even low concentrations of NOM may limit the rapidity of Ag dispersal but may also concentrate the dose received by organisms, which subsequently ingest the stabilized particles.
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Affiliation(s)
| | - Dan J Lapworth
- British Geological Survey , Wallingford, Oxon OX10 8BB, United Kingdom
| | - Daren C Gooddy
- British Geological Survey , Wallingford, Oxon OX10 8BB, United Kingdom
| | - Christine N Elgy
- Facility for Environmental Nanoparticle Analysis & Characterisation (FENAC), University of Birmingham , Edgbaston B15 2TT, United Kingdom
| | - Éugenia Valsami-Jones
- Facility for Environmental Nanoparticle Analysis & Characterisation (FENAC), University of Birmingham , Edgbaston B15 2TT, United Kingdom
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32
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Guo Z, Chen G, Zeng G, Yan M, Huang Z, Jiang L, Peng C, Wang J, Xiao Z. Are silver nanoparticles always toxic in the presence of environmental anions? CHEMOSPHERE 2017; 171:318-323. [PMID: 28027476 DOI: 10.1016/j.chemosphere.2016.12.077] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/24/2016] [Revised: 12/11/2016] [Accepted: 12/16/2016] [Indexed: 06/06/2023]
Abstract
Increasing amounts of silver nanoparticles (AgNPs) are expected to enter the ecosystems where their toxicity in the environment is proposed. In this study, we exploited the effect of environmental anions on AgNP toxicity. AgNP were mixed with various environmental anions, and then exposed to Escherichia coli to determine the effect on bacteria growth inhibition. The results demonstrated that AgNP are not always toxic in the presence of sulfide, but can stimulate microbial growth at certain concentrations. Environmental chloride and phosphate anions cannot induce the stimulation because of their weak capacity to control the release of Ag+ from AgNP. Ag+ that released from AgNP is proven to be responsible for AgNP toxicity. Moreover, we found that AgNP toxicity is dependent on sulfuration rate. At the same sulfuration rate, AgNP shows an identical pattern of toxicity. This study indicates that only sulfide of the tested environmental anions can induce AgNP stimulation to microbial growth in a sulfuration rate dependent pattern and the toxicity originate from Ag+ that released from AgNP.
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Affiliation(s)
- Zhi Guo
- College of Environmental Science and Engineering, Hunan University, Changsha 410082, PR China; Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha 410082, PR China
| | - Guiqiu Chen
- College of Environmental Science and Engineering, Hunan University, Changsha 410082, PR China; Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha 410082, PR China.
| | - Guangming Zeng
- College of Environmental Science and Engineering, Hunan University, Changsha 410082, PR China; Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha 410082, PR China.
| | - Ming Yan
- College of Environmental Science and Engineering, Hunan University, Changsha 410082, PR China; Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha 410082, PR China
| | - Zhenzhen Huang
- College of Environmental Science and Engineering, Hunan University, Changsha 410082, PR China; Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha 410082, PR China
| | - Luhua Jiang
- College of Environmental Science and Engineering, Hunan University, Changsha 410082, PR China; Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha 410082, PR China
| | - Chuan Peng
- College of Environmental Science and Engineering, Hunan University, Changsha 410082, PR China; Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha 410082, PR China
| | - Jiajia Wang
- College of Environmental Science and Engineering, Hunan University, Changsha 410082, PR China; Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha 410082, PR China
| | - Zhihua Xiao
- College of Bioscience and Biotechnology, Hunan Agricultural University, Changsha, Hunan, 410128, PR China
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Baziulyte-Paulaviciene D, Karabanovas V, Stasys M, Jarockyte G, Poderys V, Sakirzanovas S, Rotomskis R. Synthesis and functionalization of NaGdF 4:Yb,Er@NaGdF 4 core-shell nanoparticles for possible application as multimodal contrast agents. BEILSTEIN JOURNAL OF NANOTECHNOLOGY 2017; 8:1815-1824. [PMID: 28904843 PMCID: PMC5588608 DOI: 10.3762/bjnano.8.183] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/29/2017] [Accepted: 08/02/2017] [Indexed: 05/20/2023]
Abstract
Upconverting nanoparticles (UCNPs) are promising, new imaging probes capable of serving as multimodal contrast agents. In this study, monodisperse and ultrasmall core and core-shell UCNPs were synthesized via a thermal decomposition method. Furthermore, it was shown that the epitaxial growth of a NaGdF4 optical inert layer covering the NaGdF4:Yb,Er core effectively minimizes surface quenching due to the spatial isolation of the core from the surroundings. The mean diameter of the synthesized core and core-shell nanoparticles was ≈8 and ≈16 nm, respectively. Hydrophobic UCNPs were converted into hydrophilic ones using a nonionic surfactant Tween 80. The successful coating of the UCNPs by Tween 80 has been confirmed by Fourier transform infrared (FTIR) spectroscopy. Scanning electron microscopy (SEM), powder X-ray diffraction (XRD), photoluminescence (PL) spectra and magnetic resonance (MR) T1 relaxation measurements were used to characterize the size, crystal structure, optical and magnetic properties of the core and core-shell nanoparticles. Moreover, Tween 80-coated core-shell nanoparticles presented enhanced optical and MR signal intensity, good colloidal stability, low cytotoxicity and nonspecific internalization into two different breast cancer cell lines, which indicates that these nanoparticles could be applied as an efficient, dual-modal contrast probe for in vivo bioimaging.
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Affiliation(s)
| | - Vitalijus Karabanovas
- Biomedical Physics Laboratory, National Cancer Institute, Baublio str. 3b, Vilnius 2, Lithuania
- Department of Chemistry and Bioengineering, Vilnius Gediminas Technical University, Sauletekio Ave. 11, Vilnius, LT-10223, Lithuania
| | - Marius Stasys
- Biomedical Physics Laboratory, National Cancer Institute, Baublio str. 3b, Vilnius 2, Lithuania
- Biophotonics group of Laser Research Center, Faculty of Physics, Vilnius University, Sauletekio Ave. 9, Vilnius LT-10222, Lithuania
| | - Greta Jarockyte
- Biomedical Physics Laboratory, National Cancer Institute, Baublio str. 3b, Vilnius 2, Lithuania
- Biophotonics group of Laser Research Center, Faculty of Physics, Vilnius University, Sauletekio Ave. 9, Vilnius LT-10222, Lithuania
| | - Vilius Poderys
- Biomedical Physics Laboratory, National Cancer Institute, Baublio str. 3b, Vilnius 2, Lithuania
| | - Simas Sakirzanovas
- Faculty of Chemistry and Geosciences, Vilnius University, Naugarduko str. 24, Vilnius LT-03225, Lithuania
- Institute of Chemistry, Center for Physical Sciences and Technology, Sauletekio Ave. 3, Vilnius, LT-10222, Lithuania
| | - Ricardas Rotomskis
- Biomedical Physics Laboratory, National Cancer Institute, Baublio str. 3b, Vilnius 2, Lithuania
- Biophotonics group of Laser Research Center, Faculty of Physics, Vilnius University, Sauletekio Ave. 9, Vilnius LT-10222, Lithuania
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Liu J, Römer I, Tang SVY, Valsami-Jones E, Palmer RE. Crystallinity depends on choice of iron salt precursor in the continuous hydrothermal synthesis of Fe–Co oxide nanoparticles. RSC Adv 2017. [DOI: 10.1039/c7ra06647c] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
A series of Fe–Co oxide nanoparticles (NPs) were prepared by a continuous hydrothermal method using iron nitrate and ammonium iron citrate as alternative iron precursors.
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Affiliation(s)
- Jian Liu
- Nanoscale Physics Research Laboratory
- School of Physics and Astronomy
- University of Birmingham
- Birmingham B15 2TT
- UK
| | - Isabella Römer
- School of Geography
- Earth and Environmental Sciences
- University of Birmingham
- Birmingham
- UK
| | | | - Eugenia Valsami-Jones
- School of Geography
- Earth and Environmental Sciences
- University of Birmingham
- Birmingham
- UK
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Zhang Y, Xia J, Liu Y, Qiang L, Zhu L. Impacts of Morphology, Natural Organic Matter, Cations, and Ionic Strength on Sulfidation of Silver Nanowires. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2016; 50:13283-13290. [PMID: 27993058 DOI: 10.1021/acs.est.6b03034] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
Silver nanowires (AgNWs) are being widely utilized in an increasing number of consumer products, which could release silver to aquatic environments during the use or washing process, and have received growing concerns on their potential risks to bio-organisms and humans. The present study demonstrated that AgNWs mainly experienced direct oxysulfidation by reacting with dissolved sulfide species (initial S2- concentration at 1.6 mg/L) to produce silver sulfide nanostructures under environmentally relevant conditions. Granular Ag2S nanoparticles were formed on the surface of the nanowires. The sulfidation rate constant (kAg) of AgNWs was compared with those of silver nanoparticles (AgNPs) at different particle sizes. It was found that the kAg positively correlated with the specific surface areas of the silver nanomaterials. Natural organic matter (NOM) suppressed the sulfidation of AgNWs to different extents depending on its concentration. Divalent cations (Mg2+ and Ca2+ ions) substantially accelerated the sulfidation rates of AgNWs compared to monovalent cations (Na+ and K+ ions). At the same ionic strengths, Ca2+ ions displayed the highest promoting effect among the four metallic ions.
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Affiliation(s)
- Yinqing Zhang
- Key Laboratory of Pollution Processes and Environmental Criteria (Ministry of Education), Tianjin Key Laboratory of Environmental Remediation and Pollution Control, College of Environmental Science and Engineering, Nankai University , Tianjin 300350, P. R. China
| | - Junchao Xia
- Key Laboratory of Pollution Processes and Environmental Criteria (Ministry of Education), Tianjin Key Laboratory of Environmental Remediation and Pollution Control, College of Environmental Science and Engineering, Nankai University , Tianjin 300350, P. R. China
| | - Yongliang Liu
- Key Laboratory of Pollution Processes and Environmental Criteria (Ministry of Education), Tianjin Key Laboratory of Environmental Remediation and Pollution Control, College of Environmental Science and Engineering, Nankai University , Tianjin 300350, P. R. China
| | - Liwen Qiang
- Key Laboratory of Pollution Processes and Environmental Criteria (Ministry of Education), Tianjin Key Laboratory of Environmental Remediation and Pollution Control, College of Environmental Science and Engineering, Nankai University , Tianjin 300350, P. R. China
| | - Lingyan Zhu
- Key Laboratory of Pollution Processes and Environmental Criteria (Ministry of Education), Tianjin Key Laboratory of Environmental Remediation and Pollution Control, College of Environmental Science and Engineering, Nankai University , Tianjin 300350, P. R. China
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Azodi M, Sultan Y, Ghoshal S. Dissolution Behavior of Silver Nanoparticles and Formation of Secondary Silver Nanoparticles in Municipal Wastewater by Single-Particle ICP-MS. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2016; 50:13318-13327. [PMID: 27993044 DOI: 10.1021/acs.est.6b03957] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Ag nanoparticles (nAg) are used in various consumer products and a significant fraction is eventually discharged with municipal wastewater (WW). In this study we assessed the release of Ag from polyvinylpyrrolidone (PVP)- and citrate-coated 80 nm nAg in aerobic WW effluent and mixed liquor and the related changes in nAg size, using single particle ICP-MS (spICP-MS). The concentration of dissolved (nonparticulate) Ag in WW effluent was 0.89 ± 0.05 ppb at 168 h and was 71% lower than in deionized (DI) water, in batch reactors spiked with 5 × 106 PVP-nAg particles/mL (10 μg/L), an environmentally relevant concentration. Dissolved Ag in WW was partly reformed into ∼22 nm nAgxSy by inorganic sulfides and organosulfur dissolved organic carbon (DOC) after 120 h, whereas the parent nAg mean diameter decreased to 65.89 ± 0.9 nm. Reformation of nAgxSy from Ag+ also occurred in cysteine solutions but not in DI water, or humic and fulvic acid solutions. Dissolution experiments with nAg in WW mixed liquor showed qualitatively similar dissolution trends. Time-of-flight secondary ion mass spectrometry (ToF-SIMS) and X-ray photoelectron spectroscopy (XPS) analyses indicated binding of thiol- and amine-containing DOC as well as inorganic sulfides with nAg. Those WW components, as well as limited dissolved oxygen, decreased dissolution in WW.
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Affiliation(s)
- Mehrnoosh Azodi
- Department of Civil Engineering, McGill University , Montreal, Quebec, Canada
| | - Yasir Sultan
- Environment and Climate Change Canada , Gatineau, Quebec, Canada
| | - Subhasis Ghoshal
- Department of Civil Engineering, McGill University , Montreal, Quebec, Canada
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Zhang C, Hu Z, Li P, Gajaraj S. Governing factors affecting the impacts of silver nanoparticles on wastewater treatment. THE SCIENCE OF THE TOTAL ENVIRONMENT 2016; 572:852-873. [PMID: 27542630 DOI: 10.1016/j.scitotenv.2016.07.145] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/26/2016] [Revised: 07/20/2016] [Accepted: 07/20/2016] [Indexed: 05/22/2023]
Abstract
Silver nanoparticles (nanosilver or AgNPs) enter municipal wastewater from various sources, raising concerns about their potential adverse effects on wastewater treatment processes. We argue that the biological effects of silver nanoparticles at environmentally realistic concentrations (μgL-1 or lower) on the performance of a full-scale municipal water resource recovery facility (WRRF) are minimal. Reactor configuration is a critical factor that reduces or even mutes the toxicity of silver nanoparticles towards wastewater microbes in a full-scale WRRF. Municipal sewage collection networks transform silver nanoparticles into silver(I)-complexes/precipitates with low ecotoxicity, and preliminary/primary treatment processes in front of biological treatment utilities partially remove silver nanoparticles to sludge. Microbial functional redundancy and microbial adaptability to silver nanoparticles also greatly alleviate the adverse effects of silver nanoparticles on the performance of a full-scale WRRF. Silver nanoparticles in a lab-scale bioreactor without a sewage collection system and/or a preliminary/primary treatment process, in contrast to being in a full scale system, may deteriorate the reactor performance at relatively high concentrations (e.g., mgL-1 levels or higher). However, in many cases, silver nanoparticles have minimal impacts on lab-scale bioreactors, such as sequencing batch bioreactors (SBRs), especially when at relatively low concentrations (e.g., less than 1mgL-1). The susceptibility of wastewater microbes to silver nanoparticles is species-specific. In general, silver nanoparticles have higher toxicity towards nitrifying bacteria than heterotrophic bacteria.
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Affiliation(s)
- Chiqian Zhang
- Department of Civil and Environmental Engineering, University of Missouri, Columbia, MO 65211, USA.
| | - Zhiqiang Hu
- Department of Civil and Environmental Engineering, University of Missouri, Columbia, MO 65211, USA
| | - Ping Li
- College of Environment and Energy, South China University of Technology, Guangzhou 510006, PR China
| | - Shashikanth Gajaraj
- Department of Civil and Environmental Engineering, University of Missouri, Columbia, MO 65211, USA
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38
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Pettibone JM, Liu J. In Situ Methods for Monitoring Silver Nanoparticle Sulfidation in Simulated Waters. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2016; 50:11145-11153. [PMID: 27634215 DOI: 10.1021/acs.est.6b03023] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
To probe the transformation pathways of metallic nanomaterials, measurement tools capable of detecting and characterizing the broad distribution of products with limited perturbation are required. Here, we demonstrate the detection of transformation products resulting from 40 kDa PVP-coated silver nanoparticles (AgNPs) reacted in aerated, sulfide-containing water and EPA moderately hard reconstituted water standard. Using single particle inductively coupled plasma mass spectrometry, silver mass preservation in primary AgNP populations during sulfidation was observed under all reaction conditions examined. Disparate sensitivities of Ag+ and AgNPs to different media were observed, limiting confidence in the measured dissolved fraction. Examination with hyphenated asymmetric flow field-flow fractionation (A4F) methods supported similar mass preservation. Using flow-cell FTIR measurements, we provide direct evidence for the preservation of PVP-coatings in the presence of Na2S and fulvic acid, which we attributed to the observed, unprecedented Ag preservation. Using A4F and X-ray scattering, sub 10 nm AgNP populations, which have gone nearly unstudied in environmental systems, were detected and characterized in all the pristine and transformed product distributions examined. Furthermore, by distinguishing Ag+ from individual AgNPs, quantification of each population becomes tractable, which is a critical measurement need for toxicity testing and predicting NP fate in engineered and natural systems.
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Affiliation(s)
- John M Pettibone
- Material Measurement Laboratory, National Institute of Standards and Technology , Gaithersburg, Maryland 20899, United States
| | - Jingyu Liu
- Material Measurement Laboratory, National Institute of Standards and Technology , Gaithersburg, Maryland 20899, United States
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Ellis LJA, Valsami-Jones E, Lead JR, Baalousha M. Impact of surface coating and environmental conditions on the fate and transport of silver nanoparticles in the aquatic environment. THE SCIENCE OF THE TOTAL ENVIRONMENT 2016; 568:95-106. [PMID: 27289392 DOI: 10.1016/j.scitotenv.2016.05.199] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/05/2016] [Revised: 05/27/2016] [Accepted: 05/28/2016] [Indexed: 06/06/2023]
Abstract
The role of surface coating (polyvinylpyrrolidone (PVP) and citrate) and water chemistry on the fate and behavior of AgNPs in aquatic microcosms is reported in this study. The migration and transformation of the AgNPs was examined in low (ultrapure water-UPW) and high ionic strength (moderately hard water - MHW) preparations, and in the presence of modeled natural organic matter (NOM) of Suwannee River Fulvic Acid (SRFA). The migration and fate of the AgNPs in the microcosms was validated using a sedimentation-diffusion model and the aggregation behavior was monitored by UV-visible spectrometry (UV-vis). Dissolved and particulate Ag concentrations (% Ag) were analyzed by ultrafiltration methods. Imaging of the AgNPs was captured using transmission electron microscopy (TEM). Results indicate that PVP-coated AgNPs (PVP-AgNPs) remained stable for 28days with similarly distributed concentrations of the PVP-AgNPs throughout the columns in each of the water conditions after approximately 96h (4days). The sedimentation-diffusion model confirmed PVP-AgNP stability in each condition, by showing diffusion dominated transport by using the original unaltered AgNP sizes to fit the parameters. In comparison, citrate AgNPs were largely unstable in the more complex water preparations (MHW). In MHW, aggregation dominated behavior followed by sedimentation/dissolution controlled transport was observed. The addition of SRFA to MHW resulted in small stabilizing effects, to the citrate coated AgNPs, producing smaller sized AgNPs (TEM) and mixed sedimentation and diffusion migration compared the studies absent of SRFA. The results suggest that surface coating and solution chemistry has a major impact on AgNP stability, furthermore the corresponding modeling will support the experimental understanding of the overall fate of AgNPs in the environment.
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Affiliation(s)
- Laura-Jayne A Ellis
- School of Geography, Earth and Environmental Sciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK
| | - Eugenia Valsami-Jones
- School of Geography, Earth and Environmental Sciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK
| | - Jamie R Lead
- School of Geography, Earth and Environmental Sciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK; Center for Environmental Nanoscience and Risk (CENR), Department of Environmental Health Sciences, Arnold School of Public Health, University of South Carolina, Columbia 29208, USA.
| | - Mohammed Baalousha
- Center for Environmental Nanoscience and Risk (CENR), Department of Environmental Health Sciences, Arnold School of Public Health, University of South Carolina, Columbia 29208, USA.
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Baalousha M, Yang Y, Vance ME, Colman BP, McNeal S, Xu J, Blaszczak J, Steele M, Bernhardt E, Hochella MF. Outdoor urban nanomaterials: The emergence of a new, integrated, and critical field of study. THE SCIENCE OF THE TOTAL ENVIRONMENT 2016; 557-558:740-753. [PMID: 27046139 DOI: 10.1016/j.scitotenv.2016.03.132] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/19/2016] [Revised: 03/18/2016] [Accepted: 03/18/2016] [Indexed: 05/29/2023]
Abstract
Engineered nanomaterials (ENMs) are currently widely incorporated in the outdoor urban environmental fabric and numerous new applications and products containing ENMs are expected in the future. As has been shown repeatedly, products containing ENMs have the potential, at some point in their lifetime, to release ENMs into their surrounding environment. However, the expanding body in environmental nanomaterial research has not yet shifted toward ENMs in the context of the complex outdoor urban environment. This is especially surprising because the world's human populations are on a steady march toward more and more urbanization and technological development, accompanied with increased applications for ENMs in the outdoor urban environment. Our objective for this paper is therefore to review, assess, and provide new information in this emerging field. We provide an overview of nanomaterials (NMs, encompassing both ENMs and incidental nanomaterials, INMs) that are likely to be released in the urban environment from outdoor sources by discussing 1) the applications of ENMs that may lead to release of ENMs in urban areas, 2) the recently published data on the release of ENMs from novel nano-enabled applications in the outdoor urban environment, 3) the available literature on the occurrence of INMs in the atmosphere and within/on dust particles, and 4) the potential pathways and fate of NMs in the outdoor urban environment. This review is then followed by three case studies demonstrating the importance of NMs in the outdoor urban environment. The first and second case studies illustrate the occurrence of NMs in urban dust and stormwater ponds, respectively, whereas the third case study discusses the lessons learned from the release of NMs (e.g. Pt, ph and Rh) from automotive vehicle catalytic convertors. This article ends with a discussion of the research priorities needed to advance this emerging field of "outdoor urban nanomaterials" and to assess the potential risks of NMs in the context of urban environments.
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Affiliation(s)
- Mohammed Baalousha
- Center for Environmental Nanoscience and Risk, Department of Environmental Health Sciences, University of South Carolina, Columbia, SC 29208, USA.
| | - Yi Yang
- Department of Geosciences, East China Normal University, 3663 North Zhongshan Road, Shanghai, 200062, China; Center for NanoBioEarth, Department of Geosciences, Virginia Tech, Blacksburg, VA 24061-0420, USA.
| | - Marina E Vance
- Institute for Critical Technology and Applied Science, 410 Kelly Hall, Virginia Tech, Blacksburg, VA 24061-0420, USA
| | - Benjamin P Colman
- Biology Department, Duke University, Durham, NC 27708, USA; Department of Ecosystem and Conservation Sciences, University of Montana, Missoula, MT 59812, USA
| | - Samantha McNeal
- Center for Environmental Nanoscience and Risk, Department of Environmental Health Sciences, University of South Carolina, Columbia, SC 29208, USA
| | - Jie Xu
- Center for NanoBioEarth, Department of Geosciences, Virginia Tech, Blacksburg, VA 24061-0420, USA
| | | | - Meredith Steele
- College of Agriculture and Life Sciences, Virginia Tech, Blacksburg, VA 24061-0420, USA
| | | | - Michael F Hochella
- Center for NanoBioEarth, Department of Geosciences, Virginia Tech, Blacksburg, VA 24061-0420, USA; Geosciences Group, Pacific Northwest National Laboratory, Richland, WA 99354, USA
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41
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Afshinnia K, Gibson I, Merrifield R, Baalousha M. The concentration-dependent aggregation of Ag NPs induced by cystine. THE SCIENCE OF THE TOTAL ENVIRONMENT 2016; 557-558:395-403. [PMID: 27016687 DOI: 10.1016/j.scitotenv.2016.02.212] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/23/2015] [Revised: 02/25/2016] [Accepted: 02/26/2016] [Indexed: 06/05/2023]
Abstract
Cystine is widely used in cell culture media. Cysteine, the reduced form of cystine, is widely used to scavenge dissolved Ag in eco-toxicological studies to differentiate dissolved vs. nanoparticle uptake and toxicity. However, little is known about the impact of cysteine and cystine on the aggregation behavior of Ag NPs, in particular as a function of Ag NP concentration. Herein, we investigate how cystine (0-300μM) affects the stability of citrate-, polyvinylpyrrolidone-, and polyethylene glycol-coated silver nanoparticles (cit-Ag NPs, PVP-Ag NPs and PEG-Ag NPs, respectively) with and without Suwannee River fulvic acid (SRFA) as a function of Ag NPs concentration using UV-vis spectroscopy at environmentally and ecotoxicologically relevant Ag NP concentrations (ca. 125-1000μgL(-1)). The results demonstrate, for the first time, the concentration-dependent aggregation of cit-Ag NPs in the presence of cystine with a shift in the critical coagulation concentration (CCC) to lower cystine concentrations at lower cit-Ag NP concentrations. At the highest cit-Ag NP concentration (1000μgL(-1)), reaction limited aggregation was only observed and no CCC was measured. SRFA slowed the aggregation of cit-Ag NPs by cystine and aggregation occurred in reaction limited aggregation (RLA) regime only. No CCC value was measured in the presence of SRFA. Cystine replaces citrate, PVP and PEG coatings, resulting in aggregation of both electrostatically and sterically stabilized Ag NPs. These findings are important in understanding the factors determining the behavior of Ag NPs in cell culture media. Also due to the similarity between cystine and cysteine, these results are important in understanding the uptake and toxicity of Ag NPs vs. Ag ions, and suggest that the reduction of the toxicity of Ag NPs in the presence of cysteine could be due to a combined effect of scavenging Ag(+) ions and Ag NP aggregation in the presence of cysteine.
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Affiliation(s)
- K Afshinnia
- Center for Environmental Nanoscience and Risk, Department of Environmental Health Sciences, Arnold School of Public Health, University South Carolina, Columbia, SC 29208, United States
| | - I Gibson
- Center for Environmental Nanoscience and Risk, Department of Environmental Health Sciences, Arnold School of Public Health, University South Carolina, Columbia, SC 29208, United States
| | - R Merrifield
- Center for Environmental Nanoscience and Risk, Department of Environmental Health Sciences, Arnold School of Public Health, University South Carolina, Columbia, SC 29208, United States
| | - M Baalousha
- Center for Environmental Nanoscience and Risk, Department of Environmental Health Sciences, Arnold School of Public Health, University South Carolina, Columbia, SC 29208, United States.
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42
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Römer I, Wang ZW, Merrifield RC, Palmer RE, Lead J. High Resolution STEM-EELS Study of Silver Nanoparticles Exposed to Light and Humic Substances. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2016; 50:2183-2190. [PMID: 26792384 DOI: 10.1021/acs.est.5b04088] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Nanoparticles (NPs) are defined as particles with at least one dimension between 1 and 100 nm or with properties that differ from their bulk material, which possess unique properties. The extensive use of NPs means that discharge to the environment is likely increasing, but fate, behavior, and effects under environmentally relevant conditions are insufficiently studied. This paper focuses on the transformations of silver nanoparticles (AgNPs) under simulated but realistic environmental conditions. High resolution aberration-corrected scanning transmission electron microscopy (HAADF STEM) coupled with electron energy loss spectroscopy (EELS) and UV-vis were used within a multimethod approach to study morphology, surface chemistry transformations, and corona formation. Although loss, most likely by dissolution, was observed, there was no direct evidence of oxidation from the STEM-EELS. However, in the presence of fulvic acid (FA), a 1.3 nm oxygen-containing corona was observed around the AgNPs in water; modeled data based on the HAADF signal at near atomic resolution suggest this was an FA corona was formed and was not silver oxide, which was coherent (i.e., fully coated in FA), where observed. The corona further colloidally stabilized the NPs for periods of weeks to months, dependent on the solution conditions.
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Affiliation(s)
- Isabella Römer
- School of Geography Earth and Environmental Sciences, University of Birmingham , Edgbaston, Birmingham B15 2TT, United Kingdom
| | - Zhi Wei Wang
- Nanoscale Physics Research Laboratory, School of Physics and Astronomy, University of Birmingham , Edgbaston, Birmingham B15 2TT, United Kingdom
- Beijing Institute of Nanoenergy and Nanosystems , Chinese Academy of Sciences, Beijing 100083, China
| | - Ruth C Merrifield
- Center for Environmental Nanoscience and Risk (CENR), Arnold School of Public Health, University of South Carolina , Columbia, South Carolina 29208, United States
| | - Richard E Palmer
- Nanoscale Physics Research Laboratory, School of Physics and Astronomy, University of Birmingham , Edgbaston, Birmingham B15 2TT, United Kingdom
| | - Jamie Lead
- School of Geography Earth and Environmental Sciences, University of Birmingham , Edgbaston, Birmingham B15 2TT, United Kingdom
- Center for Environmental Nanoscience and Risk (CENR), Arnold School of Public Health, University of South Carolina , Columbia, South Carolina 29208, United States
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43
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Yuan ZH, Yang X, Hu A, Zheng YM, Yu CP. Assessment of the fate of silver nanoparticles in the A(2)O-MBR system. THE SCIENCE OF THE TOTAL ENVIRONMENT 2016; 544:901-907. [PMID: 26706763 DOI: 10.1016/j.scitotenv.2015.11.158] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/30/2015] [Revised: 11/28/2015] [Accepted: 11/28/2015] [Indexed: 06/05/2023]
Abstract
In this study, we employed a bench scale A(2)O-MBR (anaerobic-anoxic-oxic membrane bioreactor) system to systematically investigate the behavior and distribution of silver nanoparticles (AgNPs) in the activated sludge. The results showed that AgNPs would aggregate and form Ag-sulfur complexes in the activated sludge, and the dissolved silver only reached 13.6 μg/L when AgNPs of 5mg/L was spiked into the A(2)O-MBR. The long-term mass balance analysis showed that most of the silver contents were accumulated in the bioreactor and wasted excess sludge. Only a small fraction (less than 0.5%) of silver could get across the hollow fiber membranes with 0.1 μm nominal pore size in the effluent. In addition, the comparison between total AgNP concentration in aerobic sludge supernatant and effluent suggested that the membrane modules played a role in controlling the discharge of AgNPs into the effluent, especially under a higher influent concentration of AgNPs. Our results also showed that the adsorbed AgNPs or silver complexes in activated sludge still could release dissolved silver at the ambient pH. Thus, since activated sludge could be a sink for AgNPs, the risks of AgNPs in wasted excess sludge during utilization and disposal should be further studied.
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Affiliation(s)
- Zhi-Hua Yuan
- Key Laboratory of Urban Pollutant Conversion, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China
| | - Xiaoyong Yang
- Key Laboratory of Urban Pollutant Conversion, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China
| | - Anyi Hu
- Key Laboratory of Urban Pollutant Conversion, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China
| | - Yu-Ming Zheng
- Key Laboratory of Urban Pollutant Conversion, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China.
| | - Chang-Ping Yu
- Key Laboratory of Urban Pollutant Conversion, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China; Graduate Institute of Environmental Engineering, National Taiwan University, Taipei 106, Taiwan.
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Dogra Y, Arkill KP, Elgy C, Stolpe B, Lead J, Valsami-Jones E, Tyler CR, Galloway TS. Cerium oxide nanoparticles induce oxidative stress in the sediment-dwelling amphipod Corophium volutator. Nanotoxicology 2015; 10:480-7. [PMID: 26554927 DOI: 10.3109/17435390.2015.1088587] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Cerium oxide nanoparticles (CeO2 NPs) exhibit fast valence exchange between Ce(IV) and Ce(III) associated with oxygen storage and both pro and antioxidant activities have been reported in laboratory models. The reactivity of CeO2 NPs once they are released into the aquatic environment is virtually unknown, but this is important to determine for assessing their environmental risk. Here, we show that amphipods (Corophium volutator) grown in marine sediments containing CeO2 NPs showed a significant increase in oxidative damage compared to those grown in sediments without NPs and those containing large-sized (bulk) CeO2 particles. There was no exposure effect on survival, but significant increases in single-strand DNA breaks, lipid peroxidation and superoxide dismutase activity were observed after a 10-day exposure to 12.5 mg L(-1) CeO2. Characterisation of the CeO2 NPs dispersed in deionised or saline exposure waters revealed that more radicals were produced by CeO2 NPs compared with bulk CeO2. Electron energy loss spectroscopy (EELS) analysis revealed that both CeO2 NPs were predominantly Ce(III) in saline waters compared to deionised waters where they were predominantly Ce(IV). In both types of medium, the bulk CeO2 consisted mainly of Ce(IV). These results support a model whereby redox cycling of CeO2 NPs between Ce(III) and Ce(IV) is enhanced in saline waters, leading to sublethal oxidative damage to tissues in our test organism.
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Affiliation(s)
- Yuktee Dogra
- a Department of Biosciences , College of Life and Environmental Sciences, The Geoffrey Pope Building, University of Exeter , Exeter , UK
| | - Kenton P Arkill
- b Department of Geography , Earth and Environmental Sciences, Facility for Environmental Nanoscience Analysis and Characterisation, University of Birmingham , Edgbaston , Birmingham , UK
| | - Christine Elgy
- b Department of Geography , Earth and Environmental Sciences, Facility for Environmental Nanoscience Analysis and Characterisation, University of Birmingham , Edgbaston , Birmingham , UK
| | - Bjorn Stolpe
- b Department of Geography , Earth and Environmental Sciences, Facility for Environmental Nanoscience Analysis and Characterisation, University of Birmingham , Edgbaston , Birmingham , UK
| | - Jamie Lead
- b Department of Geography , Earth and Environmental Sciences, Facility for Environmental Nanoscience Analysis and Characterisation, University of Birmingham , Edgbaston , Birmingham , UK .,c Centre for Environmental Nanoscience and Risk, University of South Carolina , CA , USA , and
| | - Eugenia Valsami-Jones
- b Department of Geography , Earth and Environmental Sciences, Facility for Environmental Nanoscience Analysis and Characterisation, University of Birmingham , Edgbaston , Birmingham , UK .,d Department of Geography , Earth and Environmental Sciences, University of Birmingham , Edgbaston , Birmingham , UK
| | - Charles R Tyler
- a Department of Biosciences , College of Life and Environmental Sciences, The Geoffrey Pope Building, University of Exeter , Exeter , UK
| | - Tamara S Galloway
- a Department of Biosciences , College of Life and Environmental Sciences, The Geoffrey Pope Building, University of Exeter , Exeter , UK
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45
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Dale AL, Casman EA, Lowry GV, Lead JR, Viparelli E, Baalousha M. Modeling nanomaterial environmental fate in aquatic systems. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2015; 49:2587-93. [PMID: 25611674 DOI: 10.1021/es505076w] [Citation(s) in RCA: 143] [Impact Index Per Article: 15.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Mathematical models improve our fundamental understanding of the environmental behavior, fate, and transport of engineered nanomaterials (NMs, chemical substances or materials roughly 1-100 nm in size) and facilitate risk assessment and management activities. Although today's large-scale environmental fate models for NMs are a considerable improvement over early efforts, a gap still remains between the experimental research performed to date on the environmental fate of NMs and its incorporation into models. This article provides an introduction to the current state of the science in modeling the fate and behavior of NMs in aquatic environments. We address the strengths and weaknesses of existing fate models, identify the challenges facing researchers in developing and validating these models, and offer a perspective on how these challenges can be addressed through the combined efforts of modelers and experimentalists.
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Affiliation(s)
- Amy L Dale
- Department of Civil and Environmental Engineering, Carnegie Mellon University , Pittsburgh, Pennsylvania 15213, United States
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