The Experts below are selected from a list of 2130 Experts worldwide ranked by ideXlab platform

Dongmei Zhou - One of the best experts on this subject based on the ideXlab platform.

  • mechanism of significant enhancement of vo2 fenton like reactions by oxalic acid for Diethyl Phthalate degradation
    Separation and Purification Technology, 2021
    Co-Authors: Min Huang, Guodong Fang, Fengxiao Zhu, Changyin Zhu, Dongmei Zhou
    Abstract:

    Abstract It has been reported that the addition of reducing agents such as ascorbic acid and hydroxylamine to Fenton or Fenton-like systems can accelerate the circulation of Fe(III)/Fe(II), thereby accelerating the degradation of pollutants. However, few studies investigated the effect of reducing agents on pollutant degradation by heterogeneous Fenton-like reactions using other transition metals (e.g. vanadium (V) oxides) as activator. In this study, we investigated the effect of oxalic acid (OA), an inexpensive and environmentally-friendly reducing agent, on Diethyl Phthalate (DEP) degradation by VO2-Fenton-like reactions. The results showed that 92% of DEP was degraded in VO2/H2O2/OA system while only 3% and 37% of DEP was degraded with H2O2 and VO2/H2O2 respectively, demonstrating that the addition of OA can significantly promote the degradation of DEP in VO2/H2O2 system. Electron paramagnetic resonance analysis showed that OH was the dominant reactive species, which increased rapidly with the increase of OA concentration in the range of 0–2 mM. Increasing the VO2 dosage (0.1–1.0 g L−1) and OA concentration (0.05–2.0 mM) could increase the degradation rate of DEP while the increase of OA concentration was more effective in promoting DEP degradation. Moreover, in the presence of OA, DEP could be efficiently degraded over a wide pH range (pH 3–11), and OA was also found capable of promoting DEP degradation in H2O2/V(IV) and H2O2/V2O5 systems. This study provides a novel strategy to enhance Fenton-like reactions for pollutant degradation and environmental remediation.

  • ferrate vi mediated transformation of Diethyl Phthalate dep in soil kinetics degradation mechanisms and theoretical calculation
    Environmental Pollution, 2021
    Co-Authors: Wanming Cao, Dongmei Zhou, Jing Chen, Zunyao Wang
    Abstract:

    Abstract Diethyl Phthalate (DEP), as a kind of universally used plasticizer, has aroused considerable public concern owing to its wide detection, environmental stability, and potential health risks. In this work, the highly efficient removal of DEP by ferrate (VI) (Fe(VI)) was systematically explored in soil environment. The effects of the oxidant dosages, soil types, as well as the presence of coexisting cations and anions in tested soil on DEP removal were evaluated. When the dosage of Fe(VI) was 20 mM, complete removal of DEP (50 μg/g) was achieved in the tested soil after 2 min of reaction. Furthermore, the removal rate of DEP was closely related to the soil types, and the degradation rates were decreased obviously in red soil (RS), black soil (BS) and paddy soil (PS), probably due to the acidic condition and high content of organic matters. Moreover, the presence of Ca2+, Mg2+ and Al3+ in soil can inhibit the removal of DEP by Fe(VI), while SO42− has an slightly promotion effect. Six oxidation intermediates were detected in the reaction process of DEP, product analysis revealed that the transformation of DEP was mainly through two pathways, including hydrolysis and hydroxylation reactions, which were probably mediated by oxygen atom transfer process of Fe(VI). Based on the frontier electron density theory calculation, two ester groups of DEP were prone to be attacked by Fe(VI), and the hydroxyl addition tended to occur at the para-position of one of the ester groups on the benzene ring. This study provides a novel approach for Phthalate esters removal from soil using Fe(VI) oxidation and shows new insights into the oxidation mechanisms.

  • nano fe2o3 embedded in montmorillonite with citric acid enhanced photocatalytic activity of nanoparticles towards Diethyl Phthalate
    Journal of Environmental Sciences-china, 2021
    Co-Authors: Zhaoyue Sun, Guodong Fang, Dongmei Zhou, Lisha Feng, Longgang Chu, Juan Gao
    Abstract:

    Abstract Nano-Fe2O3 embedded in montmorillonite particles (Fe-Mt) were prepared to degrade Diethyl Phthalate (DEP) with citric acid (CA) under xenon light irradiation. Compared to pristine montmorillonite (Na-Mt), the embedding process increased 14.5-fold of iron content and 1.8-fold of specific surface area. The synthesized Fe-Mt have more oxygen vacancies than Fe2O3 nanoparticles (nFe2O3), which could induce more reactive oxygen species (ROSs) generation in the presence of CA under xenon lamp irradiation. Fe-Mt with CA enhanced photo-assisted degradation of DEP 2.5 times as compared to nFe2O3 with CA. Quenching experiments, electron paramagnetic resonance (EPR) spectroscopy and identification of products confirmed that surface-bound •OH was the main radical to degrade DEP. Common anions (i.e., NO3−, CO32−, Cl−) and humic acid could compete •OH with DEP and cause slower degradation of DEP. The removal efficiency of DEP was more than 56% with Fe-Mt after three recycles, and the dissolved Fe concentration from Fe-Mt was below 75 μmol/L, indicating Fe-Mt had a good stability as a catalyst. Fe-Mt together with CA appeared to be a promising strategy to remove organic pollutants in surface water, or topsoil under solar irradiation.

  • efficient activation of peroxymonosulfate by copper sulfide for Diethyl Phthalate degradation performance radical generation and mechanism
    Science of The Total Environment, 2020
    Co-Authors: Xiaolei Wang, Guodong Fang, Cun Liu, Juan Gao, Dionysios D Dionysiou, Yingzhi Ding, Yunping Tong, Dongmei Zhou
    Abstract:

    Abstract Copper-containing minerals have been extensively used in Fenton-like processes for degradation of pollutants and have exhibited great potential for environmental remediation. This work reports the first use of copper sulfide (CuS), a typical Cu-mineral, for the activation of peroxymonosulfate (PMS) for pollutant degradation; the study also elucidates the underlying mechanism of these processes. Copper sulfide effectively activated PMS to degrade Diethyl Phthalate (DEP). Electron paramagnetic resonance, free radical quenching, X-ray photoelectron spectroscopy, X-ray diffraction analyses and DFT calculations confirmed that ≡Cu (I)/≡Cu (II) cycling on the surface of CuS provided the main pathway to activate PMS to produce highly oxidative species. Unlike conventional sulfate radical-based PMS activation processes, hydroxyl radical (•OH) were found to be the dominant radical in the tested CuS/PMS system, which performed more efficiently than an alternative •OH-based oxidation system (CuS/H2O2) for DEP degradation. In addition, the presence of anions such Cl− and NO3− has limited inhibition effects on DEP degradation. Overall, this study provides an efficient pathway for PMS-based environmental remediation as well as a new insight into the mechanism of PMS activation by Cu-containing minerals.

  • efficient transformation of Diethyl Phthalate using calcium peroxide activated by pyrite
    Chemosphere, 2020
    Co-Authors: Yang Zhou, Guodong Fang, Min Huang, Xiaolei Wang, Dongmei Zhou
    Abstract:

    Abstract In this study, pyrite (FeS2) was used as a novel activator of calcium peroxide (CaO2) for the degradation of Diethyl Phthalate (DEP) in both aqueous solution and soil. DEP (10 mg/L) in aqueous solution was completely degraded within 5.0 min by the FeS2 (0.30 g/L)/CaO2 (1.0 mM) system at pH 3.5. X-ray diffraction (XRD), scanning electron microscopy (SEM), electron paramagnetic resonance (EPR), free radical quenching, and X-ray photoelectron spectroscopy (XPS) were used to elucidate the mechanism of the catalytic decomposition of CaO2, radical formation and DEP degradation in the presence of by pyrite. The results show that hydroxyl radicals ( OH) are the dominant active species responsible for DEP degradation. Surface or lattice Fe(II) of FeS2 readily activates H2O2 generated by CaO2 decomposition to produce OH, while the reducing sulfur species of FeS2 promotes the regeneration of surface of Fe(II) that catalyzes the production of additional OH, leading to the efficiently oxidative degradation of DEP. Although high concentration of common anions, such as Cl−, NO3−, SO42−, and HCO3−, exert inhibitory effects on DEP degradation by pyrite/CaO2, the reaction system can still efficiently degrade DEP in realistic soil. It was observed that 78% of DEP (25 mg kg−1) was degraded by 2.5% CaO2 (w/w) and 0.5% FeS2 (w/w) within 24 h. These results provide new insight into the mechanistic processes of CaO2 activation and OH formation by the novel FeS2 catalyst, demonstrating a promising alternative to the traditional H2O2-base Fenton process for contaminated soil remediation.

Juan Gao - One of the best experts on this subject based on the ideXlab platform.

  • nano fe2o3 embedded in montmorillonite with citric acid enhanced photocatalytic activity of nanoparticles towards Diethyl Phthalate
    Journal of Environmental Sciences-china, 2021
    Co-Authors: Zhaoyue Sun, Guodong Fang, Dongmei Zhou, Lisha Feng, Longgang Chu, Juan Gao
    Abstract:

    Abstract Nano-Fe2O3 embedded in montmorillonite particles (Fe-Mt) were prepared to degrade Diethyl Phthalate (DEP) with citric acid (CA) under xenon light irradiation. Compared to pristine montmorillonite (Na-Mt), the embedding process increased 14.5-fold of iron content and 1.8-fold of specific surface area. The synthesized Fe-Mt have more oxygen vacancies than Fe2O3 nanoparticles (nFe2O3), which could induce more reactive oxygen species (ROSs) generation in the presence of CA under xenon lamp irradiation. Fe-Mt with CA enhanced photo-assisted degradation of DEP 2.5 times as compared to nFe2O3 with CA. Quenching experiments, electron paramagnetic resonance (EPR) spectroscopy and identification of products confirmed that surface-bound •OH was the main radical to degrade DEP. Common anions (i.e., NO3−, CO32−, Cl−) and humic acid could compete •OH with DEP and cause slower degradation of DEP. The removal efficiency of DEP was more than 56% with Fe-Mt after three recycles, and the dissolved Fe concentration from Fe-Mt was below 75 μmol/L, indicating Fe-Mt had a good stability as a catalyst. Fe-Mt together with CA appeared to be a promising strategy to remove organic pollutants in surface water, or topsoil under solar irradiation.

  • efficient activation of peroxymonosulfate by copper sulfide for Diethyl Phthalate degradation performance radical generation and mechanism
    Science of The Total Environment, 2020
    Co-Authors: Xiaolei Wang, Guodong Fang, Cun Liu, Juan Gao, Dionysios D Dionysiou, Yingzhi Ding, Yunping Tong, Dongmei Zhou
    Abstract:

    Abstract Copper-containing minerals have been extensively used in Fenton-like processes for degradation of pollutants and have exhibited great potential for environmental remediation. This work reports the first use of copper sulfide (CuS), a typical Cu-mineral, for the activation of peroxymonosulfate (PMS) for pollutant degradation; the study also elucidates the underlying mechanism of these processes. Copper sulfide effectively activated PMS to degrade Diethyl Phthalate (DEP). Electron paramagnetic resonance, free radical quenching, X-ray photoelectron spectroscopy, X-ray diffraction analyses and DFT calculations confirmed that ≡Cu (I)/≡Cu (II) cycling on the surface of CuS provided the main pathway to activate PMS to produce highly oxidative species. Unlike conventional sulfate radical-based PMS activation processes, hydroxyl radical (•OH) were found to be the dominant radical in the tested CuS/PMS system, which performed more efficiently than an alternative •OH-based oxidation system (CuS/H2O2) for DEP degradation. In addition, the presence of anions such Cl− and NO3− has limited inhibition effects on DEP degradation. Overall, this study provides an efficient pathway for PMS-based environmental remediation as well as a new insight into the mechanism of PMS activation by Cu-containing minerals.

  • effects of iron hydr oxides on the degradation of Diethyl Phthalate ester in heterogeneous photo fenton reactions
    Journal of Environmental Sciences-china, 2019
    Co-Authors: Wenjuan Shuai, Guodong Fang, Dongmei Zhou, Juan Gao
    Abstract:

    Abstract This work studied the structural effects of hematite (α-Fe2O3), 2-line ferrihydrite (HFO) and goethite (α-FeOOH) on Diethyl Phthalate ester (DEP) degradation. The results showed that the degradation of DEP was faster under 365 nm light irradiation than in the dark in the presence of iron (hydr)oxides. The apparent kinetic rates of DEP degradation followed the order HFO > goethite ≈ hematite in the dark and HFO > hematite > goethite under 365 nm light irradiation. Two pathways governed H2O2 decomposition efficiency on iron (hydr)oxide surfaces: (1) forming OH on inherent surface hydroxyl groups (Fe-OH) and (2) producing O2 and H2O on the surface oxygen vacancies. X-ray photoelectron spectroscopy (XPS) analyses indicated that HFO not only has high Fe-OH content but also has high Vo content, resulting in its low H2O2 utilization efficiency (η). DEP was degraded through hydrogen abstraction and de-esterification, and the major products were (OH)2-DEP, mono-ethyl Phthalate (MEP), OH-MEP, and Phthalate acid (PA). The study is important in understanding the transformation of Phthalate esters in top surface soils and surface waters under ultraviolet light.

  • the degradation of Diethyl Phthalate by reduced smectite clays and dissolved oxygen
    Chemical Engineering Journal, 2019
    Co-Authors: Ning Chen, Guodong Fang, Dongmei Zhou, Guangxia Liu, Juan Gao
    Abstract:

    Abstract Reduced smectite clay plays an important role in producing hydroxyl radical ( OH) and degrading organic contaminants. In this study, the OH formation was examined in the suspension of reduced clay particles (Red-Na-NAu-2) with oxygen; Diethyl Phthalate (DEP), a widely detected plasticizer in soils, could be degraded in the reaction system. The results show the reactivity of Red-Na-NAu-2 is related to iron content, reduction extents and particle sizes; the oxidation process of Red-Na-NAu-2 may change structural Fe coordination or even destruct clay morphology. There are two stages in the oxidation process, fast oxidation and slow oxidation, which were closely related to active structural Fe(II) entities (e.g. Fe(II)Fe(II)Fe(II)-OH) and less active structural Fe(II) entities (e.g. Fe(II)Fe(II)-OH), respectively. It was hypothesized that dissolved oxygen could accept electrons from Fe(II) in outer surface layers (tetrahedral layers and at broken edges) based on spectra (FTIR, XPS and EELS) analyses, and inner lattice Fe(II) in octahedral layers could donate electrons to outer surface Fe(III) through one-electron pathway. The findings of this study provide a thorough understanding about the degradation of organic pollutants in subsurface environments, an omitted natural attenuating pathway, which should be important in soil remediation.

  • fe3 uvc aliphatic phenolic carboxyl acids systems for Diethyl Phthalate ester degradation a density functional theory dft and experimental study
    Applied Catalysis A-general, 2018
    Co-Authors: Dongmei Zhou, Wenjuan Shuai, Cun Liu, Yuheng Wang, Fengxiao Zhu, Juan Gao
    Abstract:

    Abstract Diethyl Phthalate ester (DEP) can be degraded in Fe3+-UV- aliphatic/phenolic carboxyl acids systems, and the degradation can be significantly influenced by different physical chemical properties of the organic acids. In this study, a density function theory (DFT) approach combined with multilinear regression analysis demonstrates that the lowest unoccupied molecular orbital energy (ELUMO) significantly negatively influenced DEP degradation. The correlation coefficient of the regression is −19.3 mM L−1 h−1. The standardized partial correlation coefficient is −0.674. The aliphatic acids group has higher catalytic ability than the phenolic carboxyl acids group, and by shifting the dominant LUMO configuration from C3s3d to Fe4s3d orbitals, Fe3+ significantly accelerates the catalytic reactions of the aliphatic acids/UV systems. Further analysis demonstrates that electron withdrawing hydroxyl group on the aliphatic acids increases the photo catalytic effects of aliphatic acids/UV system. This study highlights the important role of ELUMO of organic acids on their photocatalytic ability towards degradation of organic pollutants.

Guodong Fang - One of the best experts on this subject based on the ideXlab platform.

  • mechanism of significant enhancement of vo2 fenton like reactions by oxalic acid for Diethyl Phthalate degradation
    Separation and Purification Technology, 2021
    Co-Authors: Min Huang, Guodong Fang, Fengxiao Zhu, Changyin Zhu, Dongmei Zhou
    Abstract:

    Abstract It has been reported that the addition of reducing agents such as ascorbic acid and hydroxylamine to Fenton or Fenton-like systems can accelerate the circulation of Fe(III)/Fe(II), thereby accelerating the degradation of pollutants. However, few studies investigated the effect of reducing agents on pollutant degradation by heterogeneous Fenton-like reactions using other transition metals (e.g. vanadium (V) oxides) as activator. In this study, we investigated the effect of oxalic acid (OA), an inexpensive and environmentally-friendly reducing agent, on Diethyl Phthalate (DEP) degradation by VO2-Fenton-like reactions. The results showed that 92% of DEP was degraded in VO2/H2O2/OA system while only 3% and 37% of DEP was degraded with H2O2 and VO2/H2O2 respectively, demonstrating that the addition of OA can significantly promote the degradation of DEP in VO2/H2O2 system. Electron paramagnetic resonance analysis showed that OH was the dominant reactive species, which increased rapidly with the increase of OA concentration in the range of 0–2 mM. Increasing the VO2 dosage (0.1–1.0 g L−1) and OA concentration (0.05–2.0 mM) could increase the degradation rate of DEP while the increase of OA concentration was more effective in promoting DEP degradation. Moreover, in the presence of OA, DEP could be efficiently degraded over a wide pH range (pH 3–11), and OA was also found capable of promoting DEP degradation in H2O2/V(IV) and H2O2/V2O5 systems. This study provides a novel strategy to enhance Fenton-like reactions for pollutant degradation and environmental remediation.

  • nano fe2o3 embedded in montmorillonite with citric acid enhanced photocatalytic activity of nanoparticles towards Diethyl Phthalate
    Journal of Environmental Sciences-china, 2021
    Co-Authors: Zhaoyue Sun, Guodong Fang, Dongmei Zhou, Lisha Feng, Longgang Chu, Juan Gao
    Abstract:

    Abstract Nano-Fe2O3 embedded in montmorillonite particles (Fe-Mt) were prepared to degrade Diethyl Phthalate (DEP) with citric acid (CA) under xenon light irradiation. Compared to pristine montmorillonite (Na-Mt), the embedding process increased 14.5-fold of iron content and 1.8-fold of specific surface area. The synthesized Fe-Mt have more oxygen vacancies than Fe2O3 nanoparticles (nFe2O3), which could induce more reactive oxygen species (ROSs) generation in the presence of CA under xenon lamp irradiation. Fe-Mt with CA enhanced photo-assisted degradation of DEP 2.5 times as compared to nFe2O3 with CA. Quenching experiments, electron paramagnetic resonance (EPR) spectroscopy and identification of products confirmed that surface-bound •OH was the main radical to degrade DEP. Common anions (i.e., NO3−, CO32−, Cl−) and humic acid could compete •OH with DEP and cause slower degradation of DEP. The removal efficiency of DEP was more than 56% with Fe-Mt after three recycles, and the dissolved Fe concentration from Fe-Mt was below 75 μmol/L, indicating Fe-Mt had a good stability as a catalyst. Fe-Mt together with CA appeared to be a promising strategy to remove organic pollutants in surface water, or topsoil under solar irradiation.

  • efficient activation of peroxymonosulfate by copper sulfide for Diethyl Phthalate degradation performance radical generation and mechanism
    Science of The Total Environment, 2020
    Co-Authors: Xiaolei Wang, Guodong Fang, Cun Liu, Juan Gao, Dionysios D Dionysiou, Yingzhi Ding, Yunping Tong, Dongmei Zhou
    Abstract:

    Abstract Copper-containing minerals have been extensively used in Fenton-like processes for degradation of pollutants and have exhibited great potential for environmental remediation. This work reports the first use of copper sulfide (CuS), a typical Cu-mineral, for the activation of peroxymonosulfate (PMS) for pollutant degradation; the study also elucidates the underlying mechanism of these processes. Copper sulfide effectively activated PMS to degrade Diethyl Phthalate (DEP). Electron paramagnetic resonance, free radical quenching, X-ray photoelectron spectroscopy, X-ray diffraction analyses and DFT calculations confirmed that ≡Cu (I)/≡Cu (II) cycling on the surface of CuS provided the main pathway to activate PMS to produce highly oxidative species. Unlike conventional sulfate radical-based PMS activation processes, hydroxyl radical (•OH) were found to be the dominant radical in the tested CuS/PMS system, which performed more efficiently than an alternative •OH-based oxidation system (CuS/H2O2) for DEP degradation. In addition, the presence of anions such Cl− and NO3− has limited inhibition effects on DEP degradation. Overall, this study provides an efficient pathway for PMS-based environmental remediation as well as a new insight into the mechanism of PMS activation by Cu-containing minerals.

  • efficient transformation of Diethyl Phthalate using calcium peroxide activated by pyrite
    Chemosphere, 2020
    Co-Authors: Yang Zhou, Guodong Fang, Min Huang, Xiaolei Wang, Dongmei Zhou
    Abstract:

    Abstract In this study, pyrite (FeS2) was used as a novel activator of calcium peroxide (CaO2) for the degradation of Diethyl Phthalate (DEP) in both aqueous solution and soil. DEP (10 mg/L) in aqueous solution was completely degraded within 5.0 min by the FeS2 (0.30 g/L)/CaO2 (1.0 mM) system at pH 3.5. X-ray diffraction (XRD), scanning electron microscopy (SEM), electron paramagnetic resonance (EPR), free radical quenching, and X-ray photoelectron spectroscopy (XPS) were used to elucidate the mechanism of the catalytic decomposition of CaO2, radical formation and DEP degradation in the presence of by pyrite. The results show that hydroxyl radicals ( OH) are the dominant active species responsible for DEP degradation. Surface or lattice Fe(II) of FeS2 readily activates H2O2 generated by CaO2 decomposition to produce OH, while the reducing sulfur species of FeS2 promotes the regeneration of surface of Fe(II) that catalyzes the production of additional OH, leading to the efficiently oxidative degradation of DEP. Although high concentration of common anions, such as Cl−, NO3−, SO42−, and HCO3−, exert inhibitory effects on DEP degradation by pyrite/CaO2, the reaction system can still efficiently degrade DEP in realistic soil. It was observed that 78% of DEP (25 mg kg−1) was degraded by 2.5% CaO2 (w/w) and 0.5% FeS2 (w/w) within 24 h. These results provide new insight into the mechanistic processes of CaO2 activation and OH formation by the novel FeS2 catalyst, demonstrating a promising alternative to the traditional H2O2-base Fenton process for contaminated soil remediation.

  • effects of iron hydr oxides on the degradation of Diethyl Phthalate ester in heterogeneous photo fenton reactions
    Journal of Environmental Sciences-china, 2019
    Co-Authors: Wenjuan Shuai, Guodong Fang, Dongmei Zhou, Juan Gao
    Abstract:

    Abstract This work studied the structural effects of hematite (α-Fe2O3), 2-line ferrihydrite (HFO) and goethite (α-FeOOH) on Diethyl Phthalate ester (DEP) degradation. The results showed that the degradation of DEP was faster under 365 nm light irradiation than in the dark in the presence of iron (hydr)oxides. The apparent kinetic rates of DEP degradation followed the order HFO > goethite ≈ hematite in the dark and HFO > hematite > goethite under 365 nm light irradiation. Two pathways governed H2O2 decomposition efficiency on iron (hydr)oxide surfaces: (1) forming OH on inherent surface hydroxyl groups (Fe-OH) and (2) producing O2 and H2O on the surface oxygen vacancies. X-ray photoelectron spectroscopy (XPS) analyses indicated that HFO not only has high Fe-OH content but also has high Vo content, resulting in its low H2O2 utilization efficiency (η). DEP was degraded through hydrogen abstraction and de-esterification, and the major products were (OH)2-DEP, mono-ethyl Phthalate (MEP), OH-MEP, and Phthalate acid (PA). The study is important in understanding the transformation of Phthalate esters in top surface soils and surface waters under ultraviolet light.

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

  • a highly sensitive indirect competitive enzyme linked immunosorbent assay ic elisa by antigen coating for Diethyl Phthalate analysis in foods
    Food Analytical Methods, 2013
    Co-Authors: Mingcui Zhang, Yue Wang, Shaohui Liu
    Abstract:

    As we have known, with the plasticizer disturbance in 2011 in Taiwan, long-term exposure to Diethyl Phthalate (DEP), one of the widely used Phthalate esters, can lead to serious health problems. Therefore, a highly sensitive indirect competitive enzyme-linked immunosorbent assay (ic-ELISA) by antigen-coated plate format for DEP in foods was proposed in this paper. The polyclonal antibodies were raised against Diethyl 4-aminoPhthalate (4-DEAP) conjugated to bovine serum albumin by the amino diazotization linkage method. Coating antigen was prepared with 4-DEAP conjugated to ovalbumin using the same procedure. Under the optimal experimental conditions, the ic-ELISA has a linear working range of 0.005–18.6 ng/mL (R 2 = 0.9921), with a limit of detection of 0.0049 ng/mL. Low cross-reactivity (<9 %) to structurally related Phthalates was observed. The method was successfully applied to the determination of DEP in fruit juice, milky tea, pure milk, and sour milk, without purification or preconcentration. Satisfactory recoveries were obtained ranging from 91.1 to 109.3 %. The results suggested that the developed ic-ELISA is a simple, sensitive, and specific method for the rapid monitoring of DEP in food samples.

  • A direct competitive enzyme-linked immunosorbent assay by antibody coated for Diethyl Phthalate analysis
    Analytical Biochemistry, 2010
    Co-Authors: Mingcui Zhang, Ying Cong, Yali Sheng
    Abstract:

    Abstract A direct competitive enzyme-linked immunosorbent assay (ELISA) has been developed for detection of Diethyl Phthalate (DEP). Protein–hapten conjugate was synthesized to produce polyclonal antibodies against DEP. Experimental parameters were optimized, including immunoreaction conditions, the dilution ratio of horseradish peroxidase (HRP)–antigen conjugate, time of the antibody coated, effect of pH, and ionic strength. The limit of detection was 0.096 ng/ml, and the linear range was 0.1–3500 ng/ml with a regression coefficient ( R 2 ) of 0.9957. Recoveries were between 96.4 and 106.2%. The cross-reactivities of the anti-DEP antibody to six structurally related Phthalate esters were less than 9%. The method was successfully applied to the determination of DEP in tap water, river water (Yangtze River), and leachate from plastic drinking bottles. This immunoassay was highly specific, sensitive, rapid, simple, and suitable for DEP monitoring. The results obtained were compared with those obtained using the high-performance liquid chromatography method.

Taisheng Cheng - One of the best experts on this subject based on the ideXlab platform.

  • the toxic effects of Diethyl Phthalate on the activity of glutamine synthetase in greater duckweed spirodela polyrhiza l
    Aquatic Toxicology, 2012
    Co-Authors: Taisheng Cheng
    Abstract:

    The toxic effects of Diethyl Phthalate (DEP), a potent allelochemical, on the enzyme activity and polypeptide accumulation of glutamine synthetase (GS) in greater duckweed were investigated. In our previous studies, DEP induced oxidative responses at concentrations from 0.5 to 2 mM in greater duckweed and the antioxidant enzymes played important roles in the defense strategy against DEP stress. In this study, DAB-H(2)O(2) and NBT stain for superoxide radicals (O(2)(·-)), lipid peroxidation, HSP70, and ammonia accumulation in DEP-treated duckweed tissues revealed adverse effect of DEP in plant growth. Biochemical analysis and physiological methods were combined to investigate GS activity and polypeptide accumulation under DEP-induced stress. The results showed that GS activity was reduced with the increasing concentration of DEP, indicative of enhanced toxic effect. Immunoblot analysis with chloroplast soluble fractions indicated that the chloroplastic GS (GS2) polypeptide from greater duckweed was degraded under DEP stress conditions. The response of GS2 to the DEP stress may be modulated by means of redox change in plant tissues, chloroplasts, and chloroplast lysates. The results suggest that DEP is toxic to the greater duckweed by inhibition of the GS isoenzymes in nitrogen assimilation and the GS2 plays important roles in the adaptation strategy against DEP toxicity.

  • oxidative effects and metabolic changes following exposure of greater duckweed spirodela polyrhiza to Diethyl Phthalate
    Aquatic Toxicology, 2012
    Co-Authors: Leeju Cheng, Taisheng Cheng
    Abstract:

    The toxicity and effects of Diethyl Phthalate (DEP), a potent allelochemical, on the growth of greater duckweed were studied. Biochemical analyses and physiological methods were combined to investigate oxidative stress, adverse effects and their mechanisms in greater duckweeds grown in 0-2 mM of Diethyl Phthalate (DEP) after cultivation for 7 days. The results showed that J-shaped concentration response curves were displayed in hydrogen peroxide (H2O2), ascorbic acid (ASA) and dehydroascorbate (DHA) levels, and ascorbate peroxidase (APX) and gualacol peroxidase (POD) activities, indicating reduced oxidative stress and toxic effect. The inverted U-shaped curves were exhibited in relative growth rate (RGR), fresh weight/dry weight (FW/DW) ratio, total chlorophyll content, total soluble thiols, and glutathione reductase (GR) activity, revealing beneficial effect in plant growth. The inverted U-shaped curves were also found in malondialdehyde (MAD) and superoxide radical (O2-) contents with the increasing concentration of DEP, indicative of enhanced oxidative stress. The results suggest that DEP is toxic to the greater duckweed by inducing oxidative stress and antioxidative enzymes may play important roles in the defense strategy against DEP toxicity.