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    A new approach for the in vitro identification of the cytotoxicity of superparamagnetic iron oxide nanoparticles

    , Article Colloids and Surfaces B: Biointerfaces ; Volume 75, Issue 1 , 1 January , 2010 , Pages 300–309 Mahmoudi, M. (Morteza) ; Simchi, A. (Abdolreza) ; Imani, M. (Mohammad) ; Shokrgozar, M. A. (Mohammad A.) ; Milani, A. S. (Abbas S.) ; Hafeli, Urs O ; Stroeve, Pieter ; Sharif University of Technology
    Superparamagnetic iron oxide nanoparticles (SPIONs) are increasingly used in medical applications, such as targeting delivery and imaging. In the future, patients are more likely to be exposed to pharmaceutical products containing such particles. The study of toxicity of SPIONs has become of great importance in recent years, although the published data in this arena is limited. The aim of the present work is to investigate the cytotoxicity of SPIONs and the effect of the particles on the cell medium components. For this purpose, uncoated and polyvinyl alcohol (PVA) coated SPIONs with narrow size distribution were synthesized via a well-known coprecipitation method. The mouse fibroblast cell... 

    A mechanistic study and in-vivo toxicity bioassay on acetamiprid photodegradation over the zeolite supported cerium-based photocatalyst

    , Article Journal of Photochemistry and Photobiology A: Chemistry ; Volume 395 , 2020 Padervand, M ; Heidarpour, H ; Bargahi, A ; Sharif University of Technology
    Elsevier B.V  2020
    Photocatalysis is well-known as an effective tool for the removal of pollutants but its eco-friendly aspect has not been well explored in the literature. In this study, we prepared an ultraviolet-active photocatalyst by the growth of cerium oxide/sulfide nanoparticles in the zeolite channels via a facile coprecipitation method. The photocatalyst was comprehensively characterized by different analysis methods and showed good activity toward removal of acetamiprid, ACP, a commonly used insecticide. As the main focus of the current work, an in vivo bioassay was carried out to investigate the acute toxicity of the contaminant solutions before and after photoreaction. Accordingly, acetamiprid and... 

    Removal of toxic heavy metal ions from waste water by functionalized magnetic core–zeolitic shell nanocomposites as adsorbents

    , Article Environmental Science and Pollution Research ; Volume 20, Issue 6 , June , 2013 , pp. 3900-3909 ; 1614-7499 Padervand, M. (Mohsen) ; Gholami, M. R. (Mohammad Reza) ; Sharif University of Technology
    Functionalized magnetic core–zeolitic shell nanocomposites were prepared via hydrothermal and precipitation methods. The products were characterized by vibrating sample magnetometer, X-ray powder diffraction, Fourier transform infrared spectroscopy, nitrogen adsorption–desorption isotherms, and transmission electron microscopy analysis. The growth of mordenite nanocrystals on the outer surface of silica-coated magnetic nanoparticles at the presence of organic templates was well approved. The removal performance and the selectivity of mixed metal ions (Pb2+ and Cd2+) in aqueous solution were investigated via the sorption process. The batch method was employed to study the sorption kinetic,... 

    Formaldehyde biodegradation using an immobilized bed aerobic bioreactor with pumice stone as a support

    , Article Scientia Iranica ; Volume 18, Issue 6 , December , 2011 , Pages 1372-1376 ; 10263098 (ISSN) Ebrahimi, S ; Borghei, M ; Sharif University of Technology
    The objective of this study is the investigation of formaldehyde degradation in a bioreactor with pumice stone as a support. The reactor was tested at different synthetic wastewater concentrations with total COD of 500, 1000 and 1500 mgL, respectively, at 24 h hydraulic retention time. The effect of feed composition was tested by changing the COD TCOD FA ratio in order to analyze the impact of formaldehyde concentration. The average formaldehyde and COD removal efficiencies obtained in the reactor were 97.1% and 88%, respectively. The maximum COD and formaldehyde removal efficiencies occurred at the COD TCOD F of 41 at COD T=1000mgL. The effect of toxic shock on reactor performance was... 

    Personalized disease-specific protein corona influences the therapeutic impact of graphene oxide

    , Article Nanoscale ; Volume 7, Issue 19 , Apr , 2015 , Pages 8978-8994 ; 20403364 (ISSN) Hajipour, M. J ; Raheb, J ; Akhavan, O ; Arjmand, S ; Mashinchian, O ; Rahman, M ; Abdolahad, M ; Serpooshan, V ; Laurent, S ; Mahmoudi, M ; Sharif University of Technology
    Royal Society of Chemistry  2015
    The hard corona, the protein shell that is strongly attached to the surface of nano-objects in biological fluids, is recognized as the first layer that interacts with biological objects (e.g., cells and tissues). The decoration of the hard corona (i.e., the type, amount, and conformation of the attached proteins) can define the biological fate of the nanomaterial. Recent developments have revealed that corona decoration strongly depends on the type of disease in human patients from which the plasma is obtained as a protein source for corona formation (referred to as the 'personalized protein corona'). In this study, we demonstrate that graphene oxide (GO) sheets can trigger different... 

    The characterization of proteins involved in toxic metal resistance of a bacterial strain isolated from mine site using a proteomic approach

    , Article Pollution Research ; Volume 28, Issue 3 , 2009 , Pages 337-343 ; 02578050 (ISSN) Nemati, F ; Arabian, D ; Roostaazad, R ; Gade, W. N ; Shitole, M. G ; Sharif University of Technology
    We investigated the response of a bacterial strain isolated from low grade complex zinc and lead sulfide mines to metals toxicity (i.e., zinc, manganese, nickel, cobalt, copper, arsenate, chromium, lead, and mercury). The bacterium was identified as a strain of Aciditiobacillus ferrooxidans. The isolate showed good resistance to most of the toxic metals. The proteomics approach was used to identify the differentially expressed proteins under heavy metal stress in this strain. Four of the differentially expressed proteins were identified as major outer membrane protein of A. ferrooxidans, ribulose bisphosphate carboxylase large subunit of A. ferrooxidans, putative DNA restriction methylase,... 

    Heterogeneous catalytic ozonation by Nano-MgO is better than sole ozonation for metronidazole degradation, toxicity reduction, and biodegradability improvement

    , Article Desalination and Water Treatment ; Volume 57, Issue 35 , 2016 , Pages 16435-16444 ; 19443994 (ISSN) Kermani, M ; Bahrami Asl, F ; Farzadkia, M ; Esrafili, A ; Salahshour Arian, S ; Khazaei, M ; Dadban Shahamat, Y ; Zeynalzadeh, D ; Sharif University of Technology
    Taylor and Francis Inc  2016
    Abstract: In the current paper, the removal efficiency of metronidazole (MNZ) using a catalytic ozonation process (COP) in the presence of magnesium oxide nanocrystals, as a catalyst, was investigated in deionized water and compared with a sole ozonation process (SOP). The influence of several operational factors on both removal processes was evaluated: solution pH, MgO dosage, initial MNZ concentration, and reaction time. Biodegradability improvement, mineralization rate, oxidation intermediates, and toxicity were also studied for the COP. The results showed that MgO nanocrystals accelerated MNZ removal compared to the SOP. The optimum pH for both SOP and COP was obtained at 10 and optimum... 

    Biodegradation of 4-chlorobenzoic acid by lysinibacillus macrolides DSM54T and determination of optimal conditions

    , Article International Journal of Environmental Research ; Volume 14, Issue 2 , 2020 , Pages 145-154 Samadi, A ; Sharifi, H ; Ghobadi Nejad, Z ; Hasan Zadeh, A ; Yaghmaei, S ; Sharif University of Technology
    Springer  2020
    Chlorobenzoic acids (CBAs) are recalcitrant and toxic materials which enter the environment directly using pesticides and herbicides, or indirectly through the biodegradation of polychlorinated biphenyl (PCB) compounds. In the conducted study, biodegradation of 4-chlrobenzoic acid was investigated by Lysinibacillus macrolides DSM54T, which had previously been isolated from PCB-polluted soils. Environmental factors including pH, temperature, 4-CBA concentration and inoculation percentage were optimized using response surface methodology (RSM). 58 experiments were designed according to Historical Data, because of the arbitrary selection of experiments, and the combined effects of the... 

    The treatment of phenolic wastewater using a moving bed biofilm reactor

    , Article Process Biochemistry ; Volume 39, Issue 10 , 2004 , Pages 1177-1181 ; 00329592 (ISSN) Borghei, S. M ; Hosseini, S. H ; Sharif University of Technology
    Experiments were conducted to investigate the behaviour of moving bed biofilm reactor (MBBR) receiving a mixture of toxic (phenolic) wastewater. The study was carried out on laboratory scale using two MBBR reactors fed with synthetic wastewater. The wastewater was prepared by mixing a solution of molasses with a known amount of phenol and nutrients. Two MBBR units were operated simultaneously at different hydraulic retention times (HRT) of 24, 20, 16, 12 and 8 h while phenol concentration was in the range of 200, 400, 620 and 800 mg/l. Throughout the experiments the ratio of phenolic chemical oxygen demand (COD) concentration to total COD was changed from a ratio of 0.2 to a ratio of 1. The... 

    CFD Modeling for Mitigation of Heavy Toxic Gas Release

    , M.Sc. Thesis Sharif University of Technology Miri Ramsheh, Saeed (Author) ; Rashtchian, Davoud (Supervisor)
    The release of toxic materials causes tragic accidents every year. There are various techniques in order to mitigate the release effect of these materials such as Application of air jets, steam curtains and water curtains. In this study first, previous works are reviewed in order to select the best technique for the mitigation of heavy toxic gas release. Then CFD modeling is used to simulate this technique.
    A field situation in which chlorine gas was released upwind of water spray was simulated using the open-source software FDS (Fire Dynamic Simulator), a CFD model. Only mechanical effects of water sprays are considered; hence the effect of absorbtion is neglected. Finally tha... 

    Curcumin-loaded amine-functionalized mesoporous silica nanoparticles inhibit α-synuclein fibrillation and reduce its cytotoxicity-associated effects

    , Article Langmuir ; Volume 32, Issue 50 , 2016 , Pages 13394-13402 ; 07437463 (ISSN) Taebnia, N ; Morshedi, D ; Yaghmaei, S ; Aliakbari, F ; Rahimi, F ; Arpanaei, A ; Sharif University of Technology
    American Chemical Society  2016
    This study aimed to develop a drug carrier based on amine-functionalized mesoporous silica nanoparticles (AAS-MSNPs) for a poorly water-soluble drug, curcumin (CUR), and to study its effects on α-synuclein (α-Syn) fibrillation and cytotoxicity. Here, we show that AAS-MSNPs possess high values of loading efficiency and capacity (33.5% and 0.45 mg drug/mg MSNPs, respectively) for CUR. It is also revealed that α-Syn species interact strongly with the CUR-loaded AAS-MSNPs, leading to a significant inhibition of the fibrillation process. Furthermore, these samples reduce the toxic effects of CUR. However, drug-loaded AAS-MSNPs do not affect the cytotoxic properties of the formed fibrils... 

    New hybrid nanocomposite of copper terephthalate MOF-graphene oxide: synthesis, characterization and application as adsorbents for toxic metal ion removal from Sungun acid mine drainage

    , Article Environmental Science and Pollution Research ; Volume 24, Issue 28 , 2017 , Pages 22353-22360 ; 09441344 (ISSN) Rahimi, E ; Mohaghegh, N ; Sharif University of Technology
    The application of a hybrid Cu(tpa).GO (Cu(tpa) copper terephthalate metal organic framework, GO graphene oxide) composite as a new adsorbent for the removal of toxic metal ions was reported. New hybrid nanocomposite with excellent dispersibility and stability was successfully fabricated by the simple and effective ultrasonication method. The synthesized composite was characterized by scanning electron microscopy (SEM), UV-Vis and Fourier-transform infrared (FT-IR) techniques. The characterization results concluded that the binding mechanism of the Cu(tpa) and GO was related to both packing and hydrogen bonding. For scrutinizing the sorption activity, the prepared adsorbents were assessed... 

    The effect of influent COD and upward flow velocity on the behaviour of sulphate-reducing bacteria

    , Article Process Biochemistry ; Volume 40, Issue 7 , 2005 , Pages 2305-2310 ; 13595113 (ISSN) Shayegan, J ; Ghavipanjeh, F ; Mirjafari, P ; Sharif University of Technology
    The effect of up velocity and influent COD concentration on the activity of sulphate-reducing bacteria (SRB) in UASB reactors is discussed. To study these effects, four UASB reactors were built and utilized in parallel. Examinations were carried out in two different concentrations of molasses (500 mg COD/l and 1000 mg COD/l) and four different upward flow velocities. It was observed that at velocities greater than 1 m/h, SRB bacteria were easily washed out from the reactors due to lower density and lack of ability to form dense and firm granules. It was found that in low-strength wastewaters with a COD to sulphate ratio of 2, an upward velocity in the range of 1.5-2.5 m/h could be... 

    Adsorption behavior of toxic metal Ions on nano-structured CuO granules

    , Article Separation Science and Technology (Philadelphia) ; Volume 47, Issue 7 , 2012 , Pages 1063-1069 ; 01496395 (ISSN) Ahmadi, S. J ; Sadjadi, S ; Hosseinpour, M ; Sharif University of Technology
    In this study, copper oxide nano particles were synthesized by batchwise supercritical hydrothermal method. After preparation of CuO nano particles, they were immobilized into the porous matrix of sodium alginate. The drying process formed a very porous structure that is useful for enhancing of adsorption activity. Produced CuO particles were characterized by X-ray diffractometery (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), and BET for measuring the surface area. The prepared materials were then used as adsorbent in the removal of toxic metal ions in aqueous solution. To optimize the adsorption system, the effect of various parameters such as adsorbent... 

    Heavy metal tolerance of fungi

    , Article Scientia Iranica ; Volume 18, Issue 3 C , 2011 , Pages 502-508 ; 10263098 (ISSN) Anahid, S ; Yaghmaei, S ; Ghobadinejad, Z ; Sharif University of Technology
    This study was focused on the heavy metal (Ni, Co, Mo, V, Mn, Fe, W and Zn) tolerance of fungi strains Aspergillus niger, Aspergillus foetidus and Penicillium simplicissimum. Aspergillus niger was exposed to a mixture of Mo, V and Mn at a mass ratio of 1:2:6 as approximately present in the spent refinery processing catalyst. This study highlights the adaptation of fungi strains to Tungsten and Vanadium to high concentration. The effect of different metals and metal concentration on different strains of fungi was evaluated. Results showed that Ni was one of the most toxic metals for strains of Aspergillus and Penicillium. Aspergillus foetidus was the least tolerant, in particular for Ni, Co... 

    Study of plastics elimination in bioleaching of electronic waste using Acidithiobacillus ferrooxidans

    , Article International Journal of Environmental Science and Technology ; Volume 16, Issue 11 , 2019 , Pages 7113-7126 ; 17351472 (ISSN) Arshadi, M ; Yaghmaei, S ; Mousavi, S. M ; Sharif University of Technology
    Center for Environmental and Energy Research and Studies  2019
    Polystyrene, acrylonitrile butadiene styrene, and polypropylene are the main polymers in E-waste, existing about 31%, 16%, and 13%, respectively. In this research, the effects of the elimination of low-density materials (such as polymers and plastics) were studied using the shaking table method. Bioleaching of Cu and Ni against the original sample (Sample #1) and pre-treated sample without low-density materials (Sample #2) was compared. The amount of bioleached metals and growth characteristics (including pH, Eh, bacterial count) was investigated within 25 days. The analysis of Sample #1 showed that at pulp density of 15 g/l, 94% and 79% of Cu and Ni were recovered maximally, respectively,... 

    Photocatalytic degradation of 3-methyl-4-nitrophenol over Ag/AgCl-decorated/[MOYI]-coated/ZnO nanostructures: Material characterization, photocatalytic performance, and in-vivo toxicity assessment of the photoproducts

    , Article Environmental Technology and Innovation ; 2020 Padervand, M ; Heidarpour, H ; Goshadehzehn, M ; Hajiahmadi, S ; Sharif University of Technology
    Elsevier B.V  2020
    In this work, a facile ionic liquid-mediated method was utilized to fabricate an efficient photocatalyst for environmental remediation. The eco-friendly aspect of the treatment was explored through an in-vivo toxicity bioassay. ZnO particles, prepared by a combined solid state-pyrolysis method, were coated by 1-methyl-3-(oxiran-2ylmethyl)-1H-imidazolium-3-chloride ([MOYI]Cl) ionic liquid. Then, Ag/AgCl species were grown on the surface to make a heterojunction system leading to efficient charge separation and light absorption extension to the visible domain. The products were characterized by XRD, FTIR, SEM, EDX, DRS, BET, and PL analysis. Photocatalytic performance of the nanostructures was... 

    Investigation of Highly Concentrated Phenolic Wastewater Treatment in a Membrane Biological Reactor (MBR), and Evaluation of Furfural upon Phenol Biodegradation by an Acclimated Activated Sludge

    , M.Sc. Thesis Sharif University of Technology Mohseni, Mojtaba (Author) ; Borghei, Mehdi (Supervisor)
    Phenolic compounds are hazardous pollutants that are released into environment through wastewater discharges from variety of industries. Although good biodegradability has been reported at low concentrations, but at higher concentrations phenols are known to be antibacterial. In this study the Membrane Biological Reactor (MBR) with submerged hallow fiber membrane was operated at 25±2 ºC and pH=7.5±0.5 to treat a synthetic wastewater containing high phenol concentration (up to 5.9 g/l). Removal efficiency of phenol and COD were evaluated at four various “Hydraulic Retention Times” (HRT) of 24, 12, 8 and 4 hours. To test the tolerance of the bioreactor to phenol concentration various loading... 

    Biodegradability Studies of Atrazine in Bioreactor Receiving Low-Level COD Wastewater

    , M.Sc. Thesis Sharif University of Technology Kamanmalek, Sara (Author) ; Borghei, Mehdi (Supervisor)
    Atrazine is widely used in the agriculture as an herbicide. Due to its high mobility, Atrazine leaks into the groundwater, surface waters, and drinking water wells. Many physical and chemical methods have been suggested for removing Atrazine from aquatic environments. However, these methods are very costly, have many performance problems, produce a lot of toxic intermediates which are very harmful and dangerous, and cannot completely mineralize Atrazine. In this study, biodegradation of Atrazine by microbial consortium was evaluated in the aquatic environment. In order to assess the Atrazine removal from the aquatic environment, Fixed-Bed biofilm reactor and Moving Bed Biofilm Reactor were... 

    Analysis of Airborne Particulate Matter Toxicity and its Origin

    , M.Sc. Thesis Sharif University of Technology Sabet, Masoud (Author) ; Erhami, Mohammad (Supervisor)
    Epidemiological studies have shown a positive association between particulate matters exposure and adverse health effects. However, the insufficient knowledge about the influences of components or characteristics of these particles on their health effects and toxicity leads into inefficient control practices for reducing particulates health effects. So, relationship between particles toxicity and their emission sources and components is a valuable criterion in particle emission control strategies. Moreover, as people spend most of their time in indoor environment, investigating the main sources and components of particulate toxicity in indoor environment and finding the influence of outdoor...