1
|
Kephart J, Zhou DY, Sandwisch J, Cajiao N, Krajewski SM, Malinowski P, Chu JH, Neidig ML, Kaminsky W, Velian A. Caught in the Act of Substitution: Interadsorbate Effects on an Atomically Precise Fe/Co/Se Nanocluster. ACS CENTRAL SCIENCE 2024; 10:1276-1282. [PMID: 38947197 PMCID: PMC11212139 DOI: 10.1021/acscentsci.4c00210] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/05/2024] [Revised: 05/20/2024] [Accepted: 05/21/2024] [Indexed: 07/02/2024]
Abstract
Directing groups guide substitution patterns in organic synthetic schemes, but little is known about pathways to control reactivity patterns, such as regioselectivity, in complex inorganic systems such as bioinorganic cofactors or extended surfaces. Interadsorbate effects are known to encode surface reactivity patterns in inorganic materials, modulating the location and binding strength of ligands. However, owing to limited experimental resolution into complex inorganic structures, there is little opportunity to resolve these effects on the atomic scale. Here, we utilize an atomically precise Fe/Co/Se nanocluster platform, [Fe3(L)2Co6Se8L'6]+ ([1(L)2]+; L = CN t Bu, THF; L' = Ph2PN(-)Tol), in which allosteric interadsorbate effects give rise to pronounced site-differentiation. Using a combination of spectroscopic techniques and single-crystal X-ray diffractometry, we discover that coordination of THF at the ligand-free Fe site in [1(CN t Bu)2]+ sets off a domino effect wherein allosteric through-cluster interactions promote the regioselective dissociation of CN t Bu at a neighboring Fe site. Computational analysis reveals that this active site correlation is a result of delocalized Fe···Se···Co···Se covalent interactions that intertwine edge sites on the same cluster face. This study provides an unprecedented atom-scale glimpse into how interfacial metal-support interactions mediate a collective and regiospecific path for substrate exchange across multiple active sites.
Collapse
Affiliation(s)
- Jonathan
A. Kephart
- Department
of Chemistry, University of Washington, Seattle, Washington 98195, United States
| | - Daniel Y. Zhou
- Department
of Chemistry, University of Washington, Seattle, Washington 98195, United States
| | - Jason Sandwisch
- Department
of Chemistry, University of Washington, Seattle, Washington 98195, United States
| | - Nathalia Cajiao
- Department
of Chemistry, University of Rochester, Rochester, New York 14627, United States
| | - Sebastian M. Krajewski
- Department
of Chemistry, University of Washington, Seattle, Washington 98195, United States
| | - Paul Malinowski
- Department
of Physics, University of Washington, Seattle, Washington 98195, United States
| | - Jiun-Haw Chu
- Department
of Physics, University of Washington, Seattle, Washington 98195, United States
| | - Michael L. Neidig
- Inorganic
Chemistry Laboratory, Department of Chemistry, University of Oxford, South Parks Road, Oxford OX1 3QR, United Kingdom
| | - Werner Kaminsky
- Department
of Chemistry, University of Washington, Seattle, Washington 98195, United States
| | - Alexandra Velian
- Department
of Chemistry, University of Washington, Seattle, Washington 98195, United States
| |
Collapse
|
2
|
Liu W, Li M, Li W, Keller AA, Slaveykova VI. Metabolic alterations in alga Chlamydomonas reinhardtii exposed to nTiO 2 materials. ENVIRONMENTAL SCIENCE. NANO 2022; 9:2922-2938. [PMID: 36093215 PMCID: PMC9367718 DOI: 10.1039/d2en00260d] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/18/2022] [Accepted: 06/28/2022] [Indexed: 11/21/2022]
Abstract
Nano-sized titanium dioxide (nTiO2) is one of the most commonly used materials, however the knowledge about the molecular basis for metabolic and physiological changes in phytoplankton is yet to be explored. In the present study we use a combination of targeted metabolomics, transcriptomics and physiological response studies to decipher the metabolic perturbation in green alga Chlamydomonas reinhardtii exposed for 72 h to increasing concentrations (2, 20, 100 and 200 mg L-1) of nTiO2 with primary sizes of 5, 15 and 20 nm. Results show that the exposure to all three nTiO2 materials induced perturbation of the metabolism of amino acids, nucleotides, fatty acids, tricarboxylic acids, antioxidants but not in the photosynthesis. The alterations of the most responsive metabolites were concentration and primary size-dependent despite the significant formation of micrometer-size aggregates and their sedimentation. The metabolic perturbations corroborate the observed physiological responses and transcriptomic results and confirmed the importance of oxidative stress as a major toxicity mechanism for nTiO2. Transcriptomics revealed also an important influence of nTiO2 treatments on the transport, adenosine triphosphate binding cassette transporters, and metal transporters, suggesting a perturbation in a global nutrition of the microalgal cell, which was most pronounced for exposure to 5 nm nTiO2. The present study provides for the first-time evidence for the main metabolic perturbations in green alga C. reinhardtii exposed to nTiO2 and helps to improve biological understanding of the molecular basis of these perturbations.
Collapse
Affiliation(s)
- Wei Liu
- University of Geneva, Faculty of Sciences, Earth and Environment Sciences, Department F.-A. Forel for Environmental and Aquatic Sciences, Environmental Biogeochemistry and Ecotoxicology Uni Carl Vogt, 66 Blvd Carl-Vogt CH 1211 Geneva Switzerland
| | - Mengting Li
- University of Geneva, Faculty of Sciences, Earth and Environment Sciences, Department F.-A. Forel for Environmental and Aquatic Sciences, Environmental Biogeochemistry and Ecotoxicology Uni Carl Vogt, 66 Blvd Carl-Vogt CH 1211 Geneva Switzerland
| | - Weiwei Li
- Bren School of Environmental Science & Management, University of California Santa Barbara California 93106-5131 USA
| | - Arturo A Keller
- Bren School of Environmental Science & Management, University of California Santa Barbara California 93106-5131 USA
| | - Vera I Slaveykova
- University of Geneva, Faculty of Sciences, Earth and Environment Sciences, Department F.-A. Forel for Environmental and Aquatic Sciences, Environmental Biogeochemistry and Ecotoxicology Uni Carl Vogt, 66 Blvd Carl-Vogt CH 1211 Geneva Switzerland
| |
Collapse
|
3
|
Malatjie TS, Botha TL, Tekere M, Kuvarega AT, Nkambule TTI, Mamba BB, Msagati TAM. Toxicity assessment of TiO 2-conjugated Carbon-based nanohybrid material on a freshwater bioindicator cladoceran, Daphnia magna. AQUATIC TOXICOLOGY (AMSTERDAM, NETHERLANDS) 2022; 247:106176. [PMID: 35487150 DOI: 10.1016/j.aquatox.2022.106176] [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: 01/18/2022] [Revised: 03/28/2022] [Accepted: 04/17/2022] [Indexed: 06/14/2023]
Abstract
The application of nanocomposite materials fabricated from titanium dioxide nanoparticles (TiO2 NPs) and different carbon (C) allotropes have gained popularity in water treatment applications due to their synergistic properties. Studies to date have focused on simple forms of nanomaterials (NMs), however, with the technology development, there is a dramatic increase in production and application of these complex NMs which could result in toxicological impacts on organisms when released into aquatic environments. This raises serious concerns about their safety and the need to ascertain their potential adverse effects on aquatic organisms. While conjugated TiO2 NPs/carbon-based nanohybrids (TiO2/C-NHs) may exhibit enhanced photocatalytic activity, there is no research in the scientific community regarding their toxicological effects on D. magna, which are indicators of freshwater pollution. In this study, two under-represented TiO2/C-NHs (i.e., TiO2- conjugated carbon nanofiber (CNF), and TiO2-conjugated multi-walled carbon nanotube (CNT)) were investigated for their toxic effects on D. magna, through a series of acute toxicity tests with a set of sublethal biochemical biomarkers of oxidative stress. The lethal toxicity and oxidative stress formation of TiO2/C-NHs over 48 h revealed a concentration-dependant increase in D. magna mortality. The primary mechanism identified was the generation of ROS, which was in line with toxicity results. Light microscopy and CytoViva® images visualized D. magna interaction with the NPs, which accumulated and appeared as dark materials in the lines of the gut tract. The collective results indicate that TiO2/C-NHs have the potential to cause an effect on freshwater organisms when released into the environment. However, the relevance of TiO2/C-NHs effects needs further chronic toxicity studies since they show promise to be used in nano-bioremediation materials to treat wastewaters.
Collapse
Affiliation(s)
- Terrence S Malatjie
- Institute for Nanotechnology and Water Sustainability, College of Science, Engineering and Technology, University of South Africa, Florida Science Campus, P/Bag X6, Roodepoort 1709, South Africa.
| | - Tarryn L Botha
- Institute for Nanotechnology and Water Sustainability, College of Science, Engineering and Technology, University of South Africa, Florida Science Campus, P/Bag X6, Roodepoort 1709, South Africa
| | - Memory Tekere
- Department of Environmental Sciences, College of Agriculture & Environmental Sciences, University of South Africa, Florida Science Campus, P/Bag X6, Roodepoort 1709, South Africa
| | - Alex T Kuvarega
- Institute for Nanotechnology and Water Sustainability, College of Science, Engineering and Technology, University of South Africa, Florida Science Campus, P/Bag X6, Roodepoort 1709, South Africa
| | - Thabo T I Nkambule
- Institute for Nanotechnology and Water Sustainability, College of Science, Engineering and Technology, University of South Africa, Florida Science Campus, P/Bag X6, Roodepoort 1709, South Africa
| | - Bhekie B Mamba
- Institute for Nanotechnology and Water Sustainability, College of Science, Engineering and Technology, University of South Africa, Florida Science Campus, P/Bag X6, Roodepoort 1709, South Africa
| | - Titus A M Msagati
- Institute for Nanotechnology and Water Sustainability, College of Science, Engineering and Technology, University of South Africa, Florida Science Campus, P/Bag X6, Roodepoort 1709, South Africa.
| |
Collapse
|
4
|
Khorrami F, Kowsari MH. Tracing the origin of heterogeneities in the local structure and very sluggish dynamics of [Cho][Gly] ionic liquid confined between rutile and graphite slit nanopores: A MD study. J Chem Phys 2022; 156:214701. [DOI: 10.1063/5.0092381] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
MD simulations are used to study the biocompatible IL [Cho][Gly], confined between two parallel plates of rutile or graphite. Both the structure and dynamical behavior of the confined IL are very heterogeneous and depend effectively on the position of the ions to the pore walls. The ion z-density profile is used for segmentation of the inter-wall space into a central region and two outer layers. The behavior of ions in the central region is very similar to the bulk IL, while the behavior of the arranged ionic layers adjacent to the pore walls show the clear deviation from the bulk IL due to confinement. In general, the confined IL shows a "solid-like" dynamics at T = 353 K, especially in the outer layers near the walls as well as in the z-direction. The presence of the "IL-rutile wall" electrostatic interaction and hydrogen bonding (H-bonding) causes a significant difference in the local structure and dynamics of the IL adjacent to the rutile walls versus the graphite walls. Simulation reveals a significant decrease in the average number of key cation-anion H-bonds at the outer layers relative to the central regions of both confined systems. Recognized [Cho]+···[Gly]-···[Cho]+ bridge structure at the central region is lost in the vicinity of the rutile walls due to inaccessibility of the hydroxyl hydrogen atom, which forms a stable H-bond with the rutile oxygen site. However, another unprecedented [Gly]- bridge is confirmed and preserved near the graphite walls and cations prefer to stay parallel to the wall surface.
Collapse
Affiliation(s)
- Farzad Khorrami
- Institute for Advanced Studies in Basic Sciences, Iran, Islamic Republic of
| | - Mohammad Hossein Kowsari
- Department of Chemistry and and Center for Research in Climate Change and Global Warming (CRCC), Institute for Advanced Studies in Basic Sciences, Iran, Islamic Republic of
| |
Collapse
|
5
|
Li M, Slaveykova VI. Dual role of titanium dioxide nanoparticles in the accumulation of inorganic and methyl mercury by crustacean Daphnia magna through waterborne and dietary exposure. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2022; 295:118619. [PMID: 34915094 DOI: 10.1016/j.envpol.2021.118619] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/24/2021] [Revised: 11/20/2021] [Accepted: 12/01/2021] [Indexed: 06/14/2023]
Abstract
Titanium dioxide nanoparticles (nTiO2) are widely used in numerous products, yet their role in the accumulation and transfer of other contaminants in the aquatic food webs is not well understood. The influence of nTiO2 on inorganic (IHg) and monomethyl mercury (MeHg) accumulation in invertebrate Daphnia magna through waterborne and dietary exposure was thus thoroughly investigated. The results showed that nTiO2 led to a substantial decrease of the total mercury body burden (THg) in D. magna in direct waterborne exposure to IHg/MeHg. However, exposure to nTiO2 pre-treated with IHg/MeHg resulted in an increase of the THg body burden in daphnids. The presence of nTiO2 led to a substantial decrease of the THg in D. magna when exposed to IHg/MeHg via algal food. These effects were more pronounced for IHg than that for MeHg due to the higher adsorption capabilities of nTiO2 for IHg. In addition, high concentrations of nTiO2 favored the trophic transfer of IHg/MeHg through feeding on nTiO2 pre-treated with Hg, however lessened it when D. magna were fed on alga pre-treated with IHg/MeHg. Comparable assimilation efficiency (AE), determined as Hg retained in daphnids after depuration, was observed in D. magna when exposed to IHg/MeHg via algal food regardless the absence or presence of 20 mgL-1 nTiO2. By contrast, an increase of the AE of MeHg through feeding on nTiO2 and alga was found in the presence of higher concentration of 200 mgL-1 nTiO2. The present results will help to better understand the role of nTiO2 on bioavailability and trophic transfer of global contaminants, such as mercury, known to bioaccumulate and biomagnify in the aquatic environment.
Collapse
Affiliation(s)
- Mengting Li
- Environmental Biogeochemistry and Ecotoxicology, Department F.-A. Forel for Environmental and Aquatic Sciences, School of Earth and Environmental Sciences, Faculty of Science, University of Geneva, Uni Carl Vogt, 66, boulevard Carl-Vogt, CH-1211, Genève 4, Switzerland
| | - Vera I Slaveykova
- Environmental Biogeochemistry and Ecotoxicology, Department F.-A. Forel for Environmental and Aquatic Sciences, School of Earth and Environmental Sciences, Faculty of Science, University of Geneva, Uni Carl Vogt, 66, boulevard Carl-Vogt, CH-1211, Genève 4, Switzerland.
| |
Collapse
|
6
|
Williams OBJ, Katsiev K, Baek B, Harrison G, Thornton G, Idriss H. Direct Visualization of a Gold Nanoparticle Electron Trapping Effect. J Am Chem Soc 2022; 144:1034-1044. [PMID: 34985273 DOI: 10.1021/jacs.1c12197] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
A new atomic-scale anisotropy in the photoreaction of surface carboxylates on rutile TiO2(110) induced by gold clusters is found. STM and DFT+U are used to study this phenomenon by monitoring the photoreaction of a prototype hole-scavenger molecule, benzoic acid, over stoichiometric (s) s-TiO2, Au9/s-TiO2, and reduced (r) Au9/r-TiO2. STM results show that benzoic acid adsorption displaces a large fraction of Au clusters from the terraces toward their edges. DFT calculations explain that Au9 clusters on stoichiometric TiO2 are distorted by benzoic acid adsorption. The influence of sub-monolayers of Au on the UV/visible photoreaction of benzoic acid was explored at room temperature, with adsorbate depletion taken as a measure of activity. The empty sites, observed upon photoexcitation, occurred in elongated chains (2 to 6 molecules long) in the [11̅0] and [001] directions. A roughly 3-fold higher depletion rate is observed in the [001] direction. This is linked to the anisotropic conduction of excited electrons along [001], with subsequent trapping by Au clusters leaving a higher concentration of holes and thus an increased decomposition rate. To our knowledge this is the first time that atomic-scale directionality of a chemical reaction is reported upon photoexcitation of the semiconductor.
Collapse
Affiliation(s)
- Oscar Bentley Jerdmyr Williams
- Department of Chemistry and London Centre for Nanotechnology (LCN), University College London (UCL), WC1H 0AH, London, U.K
| | - Khabiboulakh Katsiev
- Surface Science and Advanced Characterisation, SABIC-CRD at King Abdullah University for Science and Technology (KAUST), Thuwal, 23955, Saudi Arabia
| | - Byeongjin Baek
- SABIC Global Corporate Research, Sugar Land, Texas 77478, United States
| | - George Harrison
- KAUST Solar Center (KSC), Physical Sciences and Engineering Division (PSE), King Abdullah University for Science and Technology (KAUST), Thuwal, 23955, Saudi Arabia
| | - Geoff Thornton
- Department of Chemistry and London Centre for Nanotechnology (LCN), University College London (UCL), WC1H 0AH, London, U.K
| | - Hicham Idriss
- Department of Chemistry and London Centre for Nanotechnology (LCN), University College London (UCL), WC1H 0AH, London, U.K.,Surface Science and Advanced Characterisation, SABIC-CRD at King Abdullah University for Science and Technology (KAUST), Thuwal, 23955, Saudi Arabia
| |
Collapse
|
7
|
Liu W, Shi T, Liu M, Wang Q, Liu X, Zhou Q, Lei M, Lu P, Yu L, Wei Z. Nonlinear optical property and application of yttrium oxide in erbium-doped fiber lasers. OPTICS EXPRESS 2021; 29:29402-29411. [PMID: 34615050 DOI: 10.1364/oe.433932] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/11/2021] [Accepted: 08/14/2021] [Indexed: 06/13/2023]
Abstract
Yttrium oxide (Y2O3) has garnered some attention in view of its potential to be integrated into a wide range of high-strength structural components, microelectronic and optoelectronic devices. However, the nonlinear optical research of this promising material has not been implemented yet. In this paper, not only the electronic band structures of Y2O3 are theoretically calculated but also the optical nonlinearity of Y2O3 is validated by using the fiber laser as a platform. Meanwhile, the influence of sample thickness on laser performance is further explored by using Y2O3 saturable absorbers with different thickness. Results indicate that Y2O3 not only has impressive optical nonlinearity but also is beneficial to the investigation of ultrafast photons by adjusting the thickness of Y2O3. Therefore, Y2O3 can be used as a potential saturable absorber candidate for in-depth research and application.
Collapse
|