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Jinsong Zhang - One of the best experts on this subject based on the ideXlab platform.

  • inverse relationship between Elemental Selenium nanoparticle size and inhibition of cancer cell growth in vitro and in vivo
    Food and Chemical Toxicology, 2015
    Co-Authors: Yijun Wang, Xiaochun Wan, Pingping Chen, Guangshan Zhao, Kang Sun, Jinsong Zhang
    Abstract:

    Elemental Selenium nanoparticles (SeNPs) have been demonstrated to be equivalent to selenomethionine and methylselenocysteine in upregulating selenoenzymes; however, the toxicity of SeNPs is markedly lower than these two organic Selenium compounds. The objective of this study was to determine the effect of SeNP size on cancer cell growth and ascertain whether production of reactive oxygen species (ROS) is implicated as a candidate mechanism of action. Two types of SeNPs (averaging 35 nm and 91 nm) were investigated. Cell accumulation was inhibited in vitro and in vivo in a manner inversely proportional to particle size. In vitro modeling experiments showed the reduction of SeNPs to be glutathione concentration dependent and to result in ROS formation. Both SeNP biotransformation and ROS production were size dependent, with the smaller SeNPs being more active, thereby suggesting that small-sized SeNPs are more effective in inhibiting cancer cell proliferation through an ROS mediated mechanism.

  • impact of heat treatment on size structure and bioactivity of Elemental Selenium nanoparticles
    International Journal of Nanomedicine, 2012
    Co-Authors: Jinsong Zhang, Ethan Will Taylor, Xiaochun Wan, Dungeng Peng
    Abstract:

    Background: Elemental Selenium nanoparticles have emerged as a novel Selenium source with the advantage of reduced risk of Selenium toxicity. The present work investigated whether heat treatment affects the size, structure, and bioactivity of Selenium nanoparticles. Methods and results: After a one-hour incubation of solution containing 80 nm Selenium particles in a 90°C water bath, the nanoparticles aggregated into larger 110 nm particles and nanorods (290 nm × 70 nm), leading to significantly reduced bioavailability and phase II enzyme induction in Selenium-deficient mice. When a solution containing 40 nm Selenium nanoparticles was treated under the same conditions, the nanoparticles aggregated into larger 72 nm particles but did not transform into nanorods, demonstrating that the thermostability of Selenium nanoparticles is size-dependent, smaller Selenium nanoparticles being more resistant than larger Selenium nanoparticles to transformation into nanorods during heat treatment. Conclusion: The present results suggest that temperature and duration of the heat process, as well as the original nanoparticle size, should be carefully selected when a solution containing Selenium nanoparticles is added to functional foods.

  • General, Applied and Systems Toxicology - Toxicity of Selenium Compounds and Nano‐Selenium Particles
    General Applied and Systems Toxicology, 2011
    Co-Authors: Jinsong Zhang, Julian E. Spallholz
    Abstract:

    Selenium is a necessary dietary constituent of at least 25 human selenoproteins and enzymes all containing selenocysteine. In excessive amounts, all Selenium compounds become toxic in a dose-dependent fashion to cells in vitro and to the primary target tissue of chronic Selenium toxicity, the liver. Elemental Selenium of zero valence state has long been considered to be biologically inert. With bovine serum albumin or other dispersant agents such as polysaccharide, biologically active nano-Selenium particles (Nano-Se) are formed from sodium selenite and glutathione. Different from the biologically inert black Elemental Selenium with coarse size, red Nano-Se manifests toxicity which conforms to the concern of nanotoxicity. However, compared with Selenium compounds such as sodium selenite, selenomethionine and Se-methylselenocysteine, Nano-Se is not compromised in increasing the activities of selenoenzymes including glutathione peroxidase and thioredoxin reductase at nutritional levels and phase 2 detoxification enzymes such as glutathione S-transferase at supranutritional levels, but exhibits much lower toxicities. Nano-Se is thus a potential Selenium source with a prominent characteristic of lower toxicity for supplementation. Keywords: toxicity; selenite; selenomethionine; Se-methylselenocysteine; nano-Selenium particles

  • Elemental Selenium particles at nano size nano se are more toxic to medaka oryzias latipes as a consequence of hyper accumulation of Selenium a comparison with sodium selenite
    Aquatic Toxicology, 2008
    Co-Authors: Hongcheng Li, Jinsong Zhang, Thanh Wang, Qunfang Zhou, Guibin Jiang
    Abstract:

    Recent studies have shown that Elemental Selenium particles at nano-size (Nano-Se) exhibited comparable bioavailability and less toxicity in mice and rats when compared to sodium selenite, selenomethinine and methylselenocysteine. However, little is known about the toxicity profile of Nano-Se in aquatic animals. In the present study, toxicities of Nano-Se and selenite in Selenium-sufficient Medaka fish were compared. Selenium bioaccumulation and subsequent clearance in fish livers, gills, muscles and whole bodies were examined after 10 days of exposure to Nano-Se and selenite (100 microg Se/L) and again after 7 days of depuration. Both forms of Selenium exposure effectively increased Selenium concentrations in the investigated tissues. Surprisingly, Nano-Se was found to be more hyper-accumulated in the liver compared to selenite with differences as high as sixfold. Selenium clearance of both Nano-Se and selenite occurred at similar ratios in whole bodies and muscles but was not rapidly cleared from livers and gills. Nano-Se exhibited strong toxicity for Medaka with an approximately fivefold difference in terms of LC(50) compared to selenite. Nano-Se also caused larger effects on oxidative stress, most likely due to more hyper-accumulation of Selenium in liver. The present study suggests that toxicity of nanoparticles can largely vary between different species and concludes that the evaluation of nanotoxicology should be carried out on a case-by-case basis.

  • Elemental Selenium at nano size possesses lower toxicity without compromising the fundamental effect on selenoenzymes comparison with selenomethionine in mice
    Free Radical Biology and Medicine, 2007
    Co-Authors: Huali Wang, Jinsong Zhang
    Abstract:

    Glutathione peroxidase and thioredoxin reductase are major selenoenzymes through which Selenium exerts powerful antioxidant effects. Selenium also elicits pro-oxidant effects at toxic levels. The antioxidant and pro-oxidant effects, or bioavailability and toxicity, of Selenium depend on its chemical form. Selenomethionine is considered to be the most appropriate supplemental form due to its excellent bioavailability and lower toxicity compared to various Selenium compounds. The present studies reveal that, compared with selenomethionine, Elemental Selenium at nano size (Nano-Se) possesses equal efficacy in increasing the activities of glutathione peroxidase and thioredoxin reductase but has much lower toxicity as indicated by median lethal dose, acute liver injury, and short-term toxicity. Our results suggest that Nano-Se can serve as an antioxidant with reduced risk of Selenium toxicity.

Nina K. Gusarova - One of the best experts on this subject based on the ideXlab platform.

Hongbo Zeng - One of the best experts on this subject based on the ideXlab platform.

  • understanding the interaction mechanism between Elemental Selenium and ferric hydroxide in wastewater treatment
    Industrial & Engineering Chemistry Research, 2020
    Co-Authors: Jingyi Wang, Junmeng Li, Hongbo Zeng
    Abstract:

    The conversion of Selenium oxyanions to Elemental Selenium (Se0) of low solubility and bioavailability is an effective industrial approach for Selenium management in wastewater treatment. The gener...

  • Interactions between Elemental Selenium and hydrophilic/hydrophobic surfaces: Direct force measurements using AFM
    Chemical Engineering Journal, 2016
    Co-Authors: Jingyi Wang, Junmeng Li, Hongbo Zeng
    Abstract:

    Abstract Understanding the surface interactions between Elemental Selenium (Se0) and solid substrates is of both fundamental and practical importance in biological systems, water treatment processes, and microelectromechanical/nanoelectromechanical systems where Se0 is present. In this work, for the first time, surface interactions between a Se0 sphere and substrates of varying hydrophobicity, including silica, octadecyltrichlorosilane (OTS) modified silica, and electrodeposited Se0 film, were directly measured in aqueous solutions at different pH and salinity conditions using an atomic force microscope (AFM). In 1 mM NaCl, electrical double layer forces and van der Waals forces dominated the interactions between Se0 sphere and hydrophilic silica, and the force-distance profiles could be well fitted by classic Derjaguin-Landau-Verwey-Overbeek (DLVO) theory. Additional hydrophobic attraction was found to play a role in the interactions between Se0 sphere and hydrophobic surfaces (i.e., OTS modified silica, and electrodeposited Se0 film), with Se0-OTS showing relatively larger hydrophobic decay length (D0 ∼ 1.3 nm) than Se0-Se0 (D0 ∼ 1 nm). In 0.5 M NaCl, the electrical double layer interaction was significantly compressed. The change of zeta potentials of Se0, OTS and silica surfaces with pH showed good agreement and same trend as that of the fitted surface potentials based on the force measurements. This work provides useful information regarding the interaction mechanism of Se0 and surfaces of varying hydrophobicity in aqueous solutions.

  • interactions between Elemental Selenium and hydrophilic hydrophobic surfaces direct force measurements using afm
    Chemical Engineering Journal, 2016
    Co-Authors: Jingyi Wang, Lei Xie, Chen Shi, Qingxia Liu, Hongbo Zeng
    Abstract:

    Abstract Understanding the surface interactions between Elemental Selenium (Se0) and solid substrates is of both fundamental and practical importance in biological systems, water treatment processes, and microelectromechanical/nanoelectromechanical systems where Se0 is present. In this work, for the first time, surface interactions between a Se0 sphere and substrates of varying hydrophobicity, including silica, octadecyltrichlorosilane (OTS) modified silica, and electrodeposited Se0 film, were directly measured in aqueous solutions at different pH and salinity conditions using an atomic force microscope (AFM). In 1 mM NaCl, electrical double layer forces and van der Waals forces dominated the interactions between Se0 sphere and hydrophilic silica, and the force-distance profiles could be well fitted by classic Derjaguin-Landau-Verwey-Overbeek (DLVO) theory. Additional hydrophobic attraction was found to play a role in the interactions between Se0 sphere and hydrophobic surfaces (i.e., OTS modified silica, and electrodeposited Se0 film), with Se0-OTS showing relatively larger hydrophobic decay length (D0 ∼ 1.3 nm) than Se0-Se0 (D0 ∼ 1 nm). In 0.5 M NaCl, the electrical double layer interaction was significantly compressed. The change of zeta potentials of Se0, OTS and silica surfaces with pH showed good agreement and same trend as that of the fitted surface potentials based on the force measurements. This work provides useful information regarding the interaction mechanism of Se0 and surfaces of varying hydrophobicity in aqueous solutions.

Alexander V Artemev - One of the best experts on this subject based on the ideXlab platform.

Piet N L Lens - One of the best experts on this subject based on the ideXlab platform.

  • shape change of biogenic Elemental Selenium nanomaterials from nanospheres to nanorods decreases their colloidal stability
    Environmental science. Nano, 2017
    Co-Authors: Rohan Jain, Norbert Jordan, Stephan Weiss, Rene Hubner, Piet N L Lens, Satoru Tsushima
    Abstract:

    Microbial reduction of Selenium oxyanions under mesophilic (30 °C) and thermophilic (55 °C) conditions produces biogenic Elemental Selenium nanospheres (BioSe-Nanospheres) and nanorods (BioSe-Nanorods), respectively. While the properties of BioSe-Nanospheres are well studied, the colloidal properties of BioSe-Nanorods have not yet been investigated. Therefore, this study characterized the surface properties of BioSe-Nanorods, compared their colloidal properties with BioSe-Nanospheres and elucidated the formation of BioSe-Nanorods in the presence of a capping agent. This study demonstrated that BioSe-Nanorods, like BioSe-Nanospheres, are capped by extracellular polymeric substances (EPS) as evidenced by infrared spectroscopy. The EPS capped BioSe-Nanorods were less colloidally stable than EPS capped BioSe-Nanospheres as demonstrated by the former's less negative zeta potential values when exposed to 10 mM NaCl. In fresh lake water, BioSe-Nanospheres showed a 91.6 (±0.5)% settling efficiency, while BioSe-Nanorods displayed a settling efficiency of 97.1 (±0.5)%. The lower colloidal stability and higher settling efficiency was due to a 7 times less negative surface charge of BioSe-Nanorods compared to BioSe-Nanospheres at pH 7.2. Further, this study observed that the formation of BioSe-Nanorods might proceed via BioSe-Nanospheres through orientation attachment followed by anisotropic growth as well as a solid-solution-solid mechanism. This study demonstrates the importance of the shape of nanoparticles in determining their bioremediation effectiveness and fate in the environment.

  • Sorption of zinc onto Elemental Selenium nanoparticles immobilized in Phanerochaete chrysosporium pellets
    Environmental Science and Pollution Research, 2016
    Co-Authors: Erika J. Espinosa-ortiz, Eric D Van Hullebusch, Rohan Jain, Eldon R Rene, Manisha Shakya, Piet N L Lens
    Abstract:

    The use of a novel hybrid biosorbent, Elemental Selenium nanoparticles (nSe^0) immobilized in pellets of Phanerochaete chrysosporium, to remove Zn from aqueous solutions was investigated. Fungal pellets containing nSe^0 (nSe^0-pellets) showed to be better biosorbents as they removed more Zn (88.1 ± 5.3 %) compared to Se-free fungal pellets (56.2 ± 2.8 %) at pH 4.5 and an initial Zn concentration of 10 mg L^−1. The enhanced sorption capacity of nSe^0-pellets was attributed to a higher concentration of sorption sites resulting in a more negative surface charge density, as determined by analysis of the potentiometric titration data. Fourier transform infrared spectroscopy (FT-IR) analysis of fungal pellets prior to and after being loaded with Zn showed the functional groups, including hydroxyl and carboxyl groups, involved in the sorption process. The experimental data indicated that the sorption rate of the nSe^0-pellets fitted well to the pseudo-second order kinetic model ( R ^ 2  = 0.99), and the sorption isotherm was best represented by the Sips model (Langmuir-Freundlich) with heterogeneous factor n  = 1 ( R ^ 2  = 0.99), which is equivalent to the Langmuir model. Operational advantages of fungal pelleted reactors and the Zn removal efficiencies achieved by nSe^0-pellets under mild acidic conditions make nSe^0-pellet based bioreactors an efficient biosorption process.

  • higher cd adsorption on biogenic Elemental Selenium nanoparticles
    Environmental Chemistry Letters, 2016
    Co-Authors: Rohan Jain, Domician Dominic, Norbert Jordan, Eldon R Rene, Stephan Weiss, Eric D Van Hullebusch, Rene Hubner, Piet N L Lens
    Abstract:

    Cadmium (Cd) is a carcinogenic metal contaminating the environment and ending up in wastewaters. There is therefore a need for improved methods to remove Cd by adsorption. Biogenic Elemental Selenium nanoparticles have been shown to adsorb Zn, Cu and Hg, but these nanoparticles have not been tested for Cd removal. Here we studied the time-dependency and adsorption isotherm of Cd onto biogenic Elemental Selenium nanoparticles using batch adsorption experiments. We measured ζ-potential values to assess the stability of nanoparticles loaded with Cd. Results show that the maximum Cd adsorption capacity amounts to 176.8 mg of Cd adsorbed per g of biogenic Elemental Selenium nanoparticles. The ζ-potential of Cd-loaded nanoparticles became less negative from −32.7 to −11.7 mV when exposing nanoparticles to an initial Cd concentration of 92.7 mg L−1. This is the first study that demonstrates the high Cd uptake capacity of biogenic Elemental Selenium nanoparticles, of 176.8 mg g−1, when compared to that of traditional adsorbents such as carboxyl-functionalized activated carbon, of 13.5 mg g−1. An additional benefit is the easy solid–liquid separation by gravity settling due to coagulation of Cd-loaded biogenic Elemental Selenium nanoparticles.

  • preferential adsorption of cu in a multi metal mixture onto biogenic Elemental Selenium nanoparticles
    Chemical Engineering Journal, 2016
    Co-Authors: Rohan Jain, Domician Dominic, Norbert Jordan, Eldon R Rene, Stephan Weiss, Eric D Van Hullebusch, Rene Hubner, Piet N L Lens
    Abstract:

    Abstract Preferential adsorption of Cu contained in wastewaters is desirable as the Cu can then be reprocessed and reused more easily. In this study, biogenic Elemental Selenium nanoparticles (BioSeNPs) were assessed for their ability to preferentially adsorb Cu from an equimolar mixture containing Cu, Cd and Zn. Variations in metal to BioSeNPs ratios and initial metal solution pH improved the preferential adsorption capacity of BioSeNPs toward Cu, with the ratio of Cu adsorbed to combined Cd and Zn adsorbed varying from 2.3 to 6.6. More than 78% of the added Cu was adsorbed at an initial metal solution pH of 5.2 and metal to BioSeNPs ratio of 0.21 mg mg −1 when the ratio of Cu adsorbed to the sum of Cd and Zn adsorbed was 2.3. Infrared spectroscopy revealed that the Cu, Cd and Zn were interacting with the hydroxyl and carboxyl surface functional groups of the BioSeNPs. The modeling of BioSeNPs’ acid–base titration revealed the presence of high concentrations of carboxylic groups ( C  = 60.3 mol kg −1 ) with a p K a of 3.9, providing further evidence of their interaction with Cu. The adsorption of Cu resulted in a lower colloidal stability of the BioSeNPs as indicated by more than 99% retention of added BioSeNPs after adsorption of heavy metals and filtration. BioSeNPs showed a good preferential adsorption capacity toward Cu as compared to other adsorbent. This study provides a proof-of-concept for the preferential adsorption of Cu onto BioSeNPs which are present in the effluent of a bioreactor treating Selenium oxyanions containing wastewater.

  • reduction of selenite to Elemental Selenium nanoparticles by activated sludge
    Environmental Science and Pollution Research, 2016
    Co-Authors: Rohan Jain, Eric D Van Hullebusch, Silvio Matassa, Satyendra Singh, Giovanni Esposito, Piet N L Lens
    Abstract:

    Total Selenium removal by the activated sludge process, where selenite is reduced to colloidal Elemental Selenium nanoparticles (BioSeNPs) that remain entrapped in the activated sludge flocs, was studied. Total Selenium removal efficiencies with glucose as electron donor (2.0 g chemical oxygen demand (COD) L−1) at neutral pH and 30 °C gave 2.9 and 6.8 times higher removal efficiencies as compared to the electron donors lactate and acetate, respectively. Total Selenium removal efficiencies of 79 (±3) and 86 (±1) % were achieved in shake flasks and fed batch reactors, respectively, at dissolved oxygen (DO) concentrations above 4.0 mg L−1 and 30 °C when fed with 172 mg L−1 (1 mM) Na2SeO3 and 2.0 g L−1 COD of glucose. Continuously operated reactors operating at neutral pH, 30 °C and a DO >3 mg L−1 removed 33.98 and 36.65 mg of total Selenium per gram of total suspended solids (TSS) at TSS concentrations of 1.3 and 3.0 g L−1, respectively. However, selenite toxicity to the activated sludge led to failure of a continuously operating activated sludge reactor at the applied loading rates. This suggests that a higher hydraulic retention time (HRT) or different reactor configurations need to be applied for Selenium-removing activated sludge processes.