Chelators are used in chemical analysis, in medical aplications, as water softeners, as decontamination agents on radioactive surfaces and they are ingredients in many commercial products such as ...shampoos and food preservatives. Such a synthetic chelator is EDTA (ethylenediaminetetraacetic acid). It is considered one of the tools that promises to control the heavy metal pollution in aquaculture. EDTA attaches itself to heavy metals and carries the metals from the fish body. EDTA can also slow free-radical activity produced by heavy metals in the body. Because its ability to sequester metal ions, we tried to estimate the potential risks of a chronic exposure to EDTA on tissue mobilization of some metals which have an essential role in realization of different cell functions in Prussian carp specimens. Ca, Mg, Fe, Zn. Mn and Cu, were the mineral elements we have targeted in this study. It was found that these minerals have a trend of their tissues distribution and concentration in the body of the control specimens (higher or lower related to other similar works) and EDTA presence in water led to a significant decreasing of their level in all tissues analyzed in a dose-dependent manner.
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•EDTA-β-cyclodextrin is a relatively effective and recyclable adsorbent for REEs.•A homogenous adsorption surface for REEs on the adsorbent.•The adsorption mechanism was explored by ...FTIR and EDS elemental mapping.•The multi-component adsorption was well modeled by extended Sips isotherms.•Successful recoveries of the REEs from tap water and seawater.
The separation and recovery of Rare earth elements (REEs) from diluted aqueous streams has attracted great attention in recent years because of ever-increasing REEs demand. In this study, a green synthesized EDTA-cross-linked β-cyclodextrin (EDTA-β-CD) biopolymer was prepared and employed in adsorption of aqueous REEs, such as La(III), Ce(III), and Eu(III). EDTA acts not only as cross-linker but also as coordination site for binding of REEs. The adsorption properties for the adsorption of REEs by varying experimental conditions were carried out by batch tests. The kinetics results revealed that the surface chemical sorption and the external film diffusion were the rate-determining steps of the adsorption process. The obtained maximum adsorption capacities of EDTA-β-CD were 0.343, 0.353, and 0.365mmolg−1 for La(III), Ce(III) and Eu(III), respectively. Importantly, the isotherms fitted better to Langmuir than Freundlich and Sips models, suggesting a homogenous adsorption surface for REEs on the adsorbent. Moreover, the multi-component adsorption, which was modeled by extended Sips isotherms, revealed adsorbent’s selectivity to Eu(III). More significantly, the successful recoveries of the studied ions from tap water and seawater samples makes EDTA-β-CD a promising sorbent for the preconcentration of REEs from diluted aqueous streams.
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•Enhanced Cu-EDTA decomplexation is achieved in NTP coupled with PS system.•Heat, UV, Cu2+, and Cu-EDTA contributed to PS activation.•O2−, 1O2, OH, and SO4− contributed to Cu-EDTA ...decomplexation, especially for 1O2.•Synergistic mechanisms of Cu-EDTA decomplexation in this system are proposed.
It is difficult to remove heavy metal–organic complex by conventional chemical precipitation. In this study, a novel strategy of coupling non-thermal plasma (NTP) and persulfate (PS) oxidation was developed for decomplexation of Cu-ethylenediaminetetraacetic acid (Cu-EDTA). An obvious synergistic effect between NTP and PS was achieved, resulting in 126% increase in reaction rate constant at 7 kV compared with single NTP system. PS was effectively activated by ultraviolet irradiation, heat, Cu-EDTA, and Cu2+ generated endogenously in NTP system. O2−, 1O2, OH, and SO4− contributed to Cu-EDTA decomplexation. Multiple spectroscopy analyses and Density Functional Theory calculation indicated that Cu–O and Cu–N of Cu-EDTA were destroyed. Finally, synergetic decomplexation pathways of Cu-EDTA in the NTP/PS system were proposed.
Soil amendments like ethylene-diamine-tetraacetic-acid (EDTA) have extensively been used for enhancing lead (Pb) phytoextraction. But due to its toxic effects, environment friendly substitute is ...required. Therefore, the present study was conducted to investigate the effect of EDTA and Di-iso-propanol-amine (DIPA) to enhance Pb phytoavailability and uptake by Pelargonium hortorum along with comparative toxicities of both organic amendments. For this purpose, soil was spiked with Pb concentrations (0, 500, 750, 1000 and 1500 mg kg1) and amended with EDTA and DIPA at dosage levels (0, 1.5, 3, 5, 7.5, 10 mmol kg−1) for plantation of Pelargonium hortorum. Soil samples were extracted with MgCl2, plant samples were acid digested and analyzed for metal content. Biomass and root/shoot length of Pelargonium hortorum was decreased with increase in concentration of Pb and chelating agents. Phytoavailability of Pb at 1500 mg kg−1 with EDTA 10 mmol kg−1 was 0.3-folds in comparison to DIPA at the same dosage. Pelargonium hortorum plants amended with EDTA and DIPA at 10 mmol kg−1 with Pb 1000 mg kg−1 were found to uptake Pb 5.3-fold and 2.5-folds, respectively in comparison to Pb 1000 mg kg−1 alone. Pb uptake decreased at 1500 mg kg−1 with both chelating agents. The EDTA alone and in combination with 1500 mg Pb kg−1 showed maximum genotoxicity by reducing the mitotic index and increasing the micronuclei formation. EDTA+Pb showed maximum toxicity followed by Pb and DIPA. Overall, 10 mmol kg−1 of EDTA and DIPA performed better among all dosages in enhancing phytoavailability and uptake of Pb. DIPA showed less toxicity than that caused by EDTA, with comparable ability to promote Pb phytoextraction.
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•The application of EDTA and DIPA was assessed for Pb bioavailability and uptake.•EDTA was comparatively more effective with reference to DIPA.•Phytotoxicity and genotoxicity by Pb were pronounced with EDTA application.•DIPA promoted Pb phytoextraction effectively along with reduction in toxicities.
The ADAM (a disintegrin and metalloprotease) protein family uniquely exhibits both catalytic and adhesive properties. In the well-defined process of ectodomain shedding, ADAMs transform latent, ...cell-bound substrates into soluble, biologically active derivatives to regulate a spectrum of normal and pathological processes. In contrast, the integrin ligand properties of ADAMs are not fully understood. Emerging models posit that ADAM-integrin interactions regulate shedding activity by localizing or sequestering the ADAM sheddase. Interestingly, 8 of the 21 human ADAMs are predicted to be catalytically inactive. Unlike their catalytically active counterparts, integrin recognition of these "dead" enzymes has not been largely reported. The present study delineates the integrin ligand properties of a group of non-catalytic ADAMs. Here we report that human ADAM11, ADAM23, and ADAM29 selectively support integrin alpha4-dependent cell adhesion. This is the first demonstration that the disintegrin-like domains of multiple catalytically inactive ADAMs are ligands for a select subset of integrin receptors that also recognize catalytically active ADAMs.
► Biogeochemical behavior of Pb strongly depends on its chemical speciation. ► Organic ligands modify Pb speciation and in turns, its biogeochemical behavior. ► Effect of organic ligand on Pb ...behavior vary with soil characteristics. ► Efficiency of organic ligands to modify Pb behavior vary with their binding capacity.
Biogeochemical behavior of lead (Pb), a persistent hazardous pollutant of environmental concern, strongly depends on its chemical speciation. Therefore, in this review, link between Pb speciation: presence of organic ligands and its environmental behavior has been developed. Both, biogeochemical and ecotoxicological data are discussed in environmental risk assessment context and phytoremediation studies. Three kinds of organic ligands selected for this review include: (1) ethylene diamine tetra-acetic acid (EDTA), (2) low molecular weight organic acids (LMWOAs) and (3) humic substances (HSs). The review highlights the effect of Pb speciation on: (i) Pb fate and behavior in soil; (ii) Pb plant uptake and accumulation in different plant parts; and (iii) Pb-induced phyto-toxicity. Effects of organic ligands on Pb speciation are compared: how they can change Pb speciation modifying accordingly its fate and biogeochemistry in soil-plant system? EDTA forms soluble, stable and phytoavailable Pb-chelates due to high binding Pb affinity. LMWOAs can solubilize Pb in soil by decreasing soil pH or increasing soil organic contents, but have little effect on its translocation. Due to heterogeneous structure, HSs role is complex. In consequence Pb speciation knowledge is needed to discuss phyto-toxicity data and improved soil phytoremediation techniques.
•The Cu(II)–EDTA removal by NNN-SBA-15 from dilute solution was effective.•The sorption can reach equilibrium within 2min.•Coexistence of EDTA species increased the capture ability of copper.•XPS ...results showed that electrostatic interaction was the main sorption mechanism.
The preparation and application of tri-ammonium-functionalized mesoporous silica SBA-15 (NNN-SBA-15) for sequestering Cu(II)–EDTA chelates from aqueous solution with low concentration of 0.1mmol/L were explored. The adsorption properties of copper in the presence of equimolar EDTA were examined as a function of initial pH, ionic strength, initial concentration and temperature. Results revealed that the adsorption of Cu(II)–EDTA chelates on NNN-SBA-15 achieved equilibrium within 2min and fitted well with the Langmuir model. The maximum copper adsorption capacity was estimated to be 26.3mg/g. High ionic strength (0.1mol/L of NaNO3) influenced the removal of Cu(II)–EDTA chelates, while temperature (from 15 to 35°C) had slight effect on the adsorption capacity. Compared with the copper sorption system without EDTA species, the capture ability of copper increased significantly with coexistence of EDTA species in acidic condition. XPS spectrum studies indicated that Cu(II)–EDTA was removed from aqueous solution by the electrostatic interaction and hydrogen bond interaction between the protonated amine groups of NNN-SBA-15 and Cu(II)-EDTA chelates.
Alternating-current scanning electrochemical microscopy (AC-SECM) is introduced to monitor the local activity of Zn and Zn-10Al alloy electrodes. In-situ AC-SECM maps at potentials near the open ...circuit potential (OCP) in 2 M NaCl (pH 10) indicate that the surfaces of Zn and Zn-10Al alloy electrodes are covered with the passivation layer. When the electrolyte is exchanged with a 0.1 M ethylenediaminetetraacetic acid (EDTA) containing electrolyte, AC-SECM maps at the potential near the OCP clearly reveal the active Zn and the distinct difference between Al- and Zn-rich phases. Thereby, it is demonstrated that EDTA enhances the electrochemical activities of Zn and Zn-10Al alloy electrodes. With shifting the potential to anodic potential of −1.0 V in 0.1 M EDTA containing electrolyte, the interfacial difference between Al- and Zn-rich phases slowly disappears in AC-SECM maps, confirming that the local activity of the surface observed by AC-SECM is only attributed to the metal-EDTA complex. It is noteworthy that the hindered diffusion at the confined space between the tip and the substrate (∼ 10 µm) certainly influences on the local activities of Zn and Zn-10Al alloy electrodes. Additionally, AFM results indicate that the slightly different interactions of EDTA with Al- and Zn-rich phases cause the roughness contrast.
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•Ag-Co nanoparticles with rich catalytic sites are effectively decorated on Fe3O4@EDTA by co-reducing agent in-situ deposition method for the first time.•The Ag-Co@EDTA@Fe3O4 NPs ...expressed high saturation magnetization.•The enhanced catalytic activity of Ag-Co@EDTA@Fe3O4 NPs towards 2-nitrophenol reduction was explored.•The hydrodynamic diameter of Ag-Co@EDTA@Fe3O4 NPs was unobviously increased after 5 cycle times.
In this study, firstly, bimetallic Ag-Co nanoparticles with rich catalytic sites decorated on Fe3O4 magnetic carriers through metal ion chelating agent EDTA (Ag-Co@EDTA@Fe3O4 NPs) were fabricated by co-reducing agent in-situ deposition method for the first time. The synthesized nanocomposites were characterized by various techniques, including UV–vis, XRD, TEM, EDX, XPS and VSM. Secondly, the catalytic reduction performance of Ag-Co@EDTA@Fe3O4 NPs was analyzed for 2-nitrophenol in the presence of NaBH4 at 25 ℃. Results showed that the k of Ag-Co@EDTA@Fe3O4 NPs was 10.9 and 2.7 times higher than that of Co@EDTA@Fe3O4 and Ag@EDTA@Fe3O4 NPs, respectively, which considered to obey the first-order kinetics equation, proving the strong synergistic effect between Ag and Co nanoparticles. Furthermore, the significantly enhanced catalytic activity of Ag-Co@EDTA@Fe3O4 NPs was discussed. Plenty of Ag NPs were successfully anchored on Fe3O4@EDTA supports maybe the crucial factor, and the doped Co provided much more active sites in the catalytic process. Finally, the degradation efficiency of Ag-Co@EDTA@Fe3O4 NPs still remained above 95% after 5 cycles. Importantly, there was no significant difference between the fresh catalyst and after cycling for 5 times, observed by TEM and SEM. Meanwhile, the change of hydrodynamic diameter of the used Ag-Co@EDTA@Fe3O4 NPs over cycle number was measured around 230 nm which increased unobviously, making it a promising candidate for wastewater treatment in industries.
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•EDTA-based adsorbents for the removal of metal ions are reviewed for the first time.•The adsorption thermodynamics, isotherm model, and kinetics model are discussed.•Their ...applications and regeneration are introduced in this review.
Ethylene diamine tetraacetic acid (EDTA) is an excellent chelating agent. Its two amino groups and four carboxyl groups can be used as the binding sites of metal ions. EDTA can form stable water-soluble chelates with almost all transition metal ions. Meanwhile, EDTA is grafted onto the adsorbents through physical or chemical modification to improve the performance of the adsorbents. Therefore, EDTA-based adsorbents for the removal of metal ions in wastewater have attracted extensive attention in recent years. This article reviews the advantages and disadvantages of different types of EDTA-based adsorbents from the aspects of preparation, adsorption capacity, adsorption rate, adsorption mechanism, and regeneration. In addition, the potential applications and limitations of EDTA-based adsorbents are summarized. Finally, the challenges and future development directions of EDTA-based adsorbents are prospected.
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