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•EDTA grafted silica was prepared and used as an adsorbent for Cu(II), Zn(II) and NI(II).•Adsorption of heavy metals followed pseudo-second order kinetics and Langmuir ...isotherm.•Intra-particle diffusion mechanism was involved in the removal of heavy metals.•Adsorption process was spontaneous and endothermic in nature.
Ethylenediaminetetraacetic acid (EDTA) functionalized silica adsorbent has been synthesized using (3-aminopropyl) triethoxylsilane (APTES) as a bridging link between silanol groups (SiOH) of silica and carboxylic group of EDTA. Fourier transform infrared spectroscopy (FTIR) and Temperature-programmed oxidation (TPO) analysis confirmed the grafting of EDTA onto the silica. The synthesized EDTA–silica was investigated as an adsorbent for removal of Cu(II), Zn(II) and Ni(II) from aqueous solution. The effect of solution pH, initial solution concentration, and contact time were studied. The removal of metal ions increased with the increase in solution pH, contact time and concentration. The maximum equilibrium time was found to be 45min for all three metal ions. Kinetics studies revealed that the adsorption of Cu(II), Zn(II) and Ni(II) onto EDTA–silica followed the pseudo-second order kinetics and film diffusion and intra-particle diffusion mechanism were involved. Adsorption equilibrium data were well fitted to Langmuir isotherm model and maximum monolayer adsorption capacity for Cu(II), Zn(II) and Ni(II) was 79.36, 74.07 and 67.56mgg−1, respectively. Thermodynamic results reveal that the removal of metals onto EDTA–silica was endothermic and spontaneous in nature.
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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.
•A combinative strategy involving TiCl3 coagulation and microfiltration membrane was firstly applied to remove Ni-EDTA.•Ni2+ and TOC removal efficiency in the combinative process was achieved to 97 % ...and 93 % in synthetic electroplating wastewater, respectively.•The released Ni2+ was reduced to Ni0 by Ti3+ and the dissociated EDTA would combine with oxidized Ti4+ to form Ti-EDTA.•The transformants after reaction were insoluble, precipitable, and easy to be separated via microfiltration.
Ni-EDTA is a common heavy metal complex found in electroplating wastewater. As heavy metal complexes are stable and highly toxic, it is essential to develop efficient strategies to remove. In this work, TiCl3 coagulation and ceramic microfiltration membrane were combined in the removal of Ni-EDTA. Based on the results, this combinative process exhibited a high Ni-EDTA removal efficiency. When compared to employing the TiCl3 coagulation process only, the combinative process improved Ni2+ and TOC removal efficiencies from 91 % to 97 % and from 60 % to 93 %, respectively. Furthermore, it was found that the in-situ formed titanium hydrolysates possessed good adsorption for EDTA and Ni-EDTA, with maximum capacities reaching 713 mg/g and 213 mg/g, respectively, which also enabled the cake layer a considerable secondary removal for TOC. Mechanistic investigations confirmed that the reducibility of Ti3+ contributed to both Ni-EDTA and EDTA removal. In the presence of Ti3+, Ni-EDTA was decomplexed and the released Ni2+ was reduced to Ni0 synchronously. Meanwhile, some dissociated EDTA would combine with oxidized Ti4+ to form Ti-EDTA and ultimately promote the formation of TiO2 crystals. The formation of the insoluble chelate Ti-EDTA and the adsorption by surface hydroxyl of TiO2 were the key reasons for the efficient removal for released EDTA. This work provides a new approach for the decomplexation and harmless separation of heavy metal complexes.
•Novel eye drops for the indication of treating early-stage age-related cataracts.•Significantly improved visual function as measured by mesopic contrast sensitivity.•Densitometric analysis with ...Scheimpflug imaging showed reduced lens density.•Subgroup analysis from an FDA phase 1/2 U.S. multi-center clinical trial.
To explore the efficacy of topical 2.6% EDTA ophthalmic solution (C-KAD) as a treatment to improve visual function for the subgroup of patients with loss of contrast sensitivity (CS) due to early-stage age-related cataract.
Subgroup analysis of randomized, double-blinded, placebo-controlled, multicenter phase 1/2 clinical trial data.
Both eyes of subjects in the intent-to-treat population, with mesopic CS scores between 1 and 7 grating patches (range 0-9, each patch representing 0.15 logCS), at baseline in all five frequencies, were included. The proportion of eyes with clinically significant mesopic CS improvement and mean changes in mesopic CS at spatial frequencies between 1.5 to 18 cycles per degree (cpd), and summary metrics of area under the log CS function (AULCSF), were analyzed. Other exploratory outcomes analyzed included best-corrected visual acuity (BCVA) and lens density for a smaller subgroup of eyes for which Scheimpflug images were available.
Forty-one subject eyes were included in the subgroup analysis (C-KAD n = 21, placebo n = 20). The primary endpoint of the proportion of eyes with mesopic CS improvements ≥ 0.30 logCS (equivalent to 100% CS improvement) in at least two of the five spatial frequencies was significantly greater for C-KAD (66.7% versus 35.0% for placebo, P = .043) at Day 120. C-KAD met the primary protocol endpoint in this subgroup analysis. The proportion of eyes achieving ≥ 0.30 logCS improvement (mesopic) as measured in AULCSF was also significantly greater for C-KAD, with 42.9% compared to 15.0% for placebo (P = .050) at Day 120. The mean change in AULCSF (mesopic) was significantly larger for C-KAD, with 0.25 logCS improvement, versus placebo with 0.06 logCS improvement (P = .020) at Day 120. C-KAD also showed significant mesopic CS improvements at spatial frequencies 3 and 6 cpd, with 0.28 logCS (P = .004) and 0.31 logCS (P = .047) versus placebo at Day 120. Positive BCVA trends and statistical significance in lens density were also observed.
A significant treatment effect of C-KAD in visual function and vision quality was observed consistently. These promising results suggest a novel, non-invasive pharmacological treatment to improve vision in patients with early-stage cataract.
Porcine reproductive and respiratory syndrome (PRRS) caused by PRRS virus (PRRSV) is one of the most severe swine diseases that affects almost all swine-breeding countries. Nonstructural protein 2 ...(NSP2) is one of the most important viral proteins in the PRRSV life cycle. Our previous study showed that PRRSV NSP2 could induce the formation of aggresomes. In this study we explored the effects of aggresome formation on cells and found that NSP2 could induce autophagy, which depended on aggresome formation to activate aggrephagy. The transmembrane and tail domains of NSP2 contributed to aggrephagy and the cellular protein 14-3-3epsilon played an important role in NSP2-induced autophagy by binding the tail domain of NSP2. These findings provide information on the function of the C-terminal domain of NSP2, which will help uncover the function of NSP2 during PRRSV infection. Keywords: PRRSV, NSP2, Aggrephagy, 14-3-3epsilon, Tail domain of NSP2
Nanomaterials are used in practically every aspect of modern life, including agriculture. The aim of this study was to evaluate the effectiveness of iron oxide nanoparticles (Fe2O3 NPs) as a ...fertilizer to replace traditional Fe fertilizers, which have various shortcomings. The effects of the Fe2O3 NPs and a chelated-Fe fertilizer (ethylenediaminetetraacetic acid-Fe; EDTA-Fe) fertilizer on the growth and development of peanut (Arachis hypogaea), a crop that is very sensitive to Fe deficiency, were studied in a pot experiment. The results showed that Fe2O3 NPs increased root length, plant height, biomass, and SPAD values of peanut plants. The Fe2O3 NPs promoted the growth of peanut by regulating phytohormone contents and antioxidant enzyme activity. The Fe contents in peanut plants with Fe2O3 NPs and EDTA-Fe treatments were higher than the control group. We used energy dispersive X-ray spectroscopy (EDS) to quantitatively analyze Fe in the soil. Peanut is usually cultivated in sandy soil, which is readily leached of fertilizers. However, the Fe2O3 NPs adsorbed onto sandy soil and improved the availability of Fe to the plants. Together, these results show that Fe2O3 NPs can replace traditional Fe fertilizers in the cultivation of peanut plants. To the best of our knowledge, this is the first research on the Fe2O3 NPs as the iron fertilizer.
Phytoremediation is an ecofriendly technique to clean heavy metals from contaminated soil by the use of high biomass producing plant species. Chelators can help to improve this biological technique ...by increasing metal solubility. Therefore, a pot experiment was conducted to determine the effect of the chelators EDTA and citric acid (CA) in phytoremediation of Ni contaminated soil by using Brassica napus (canola). Two cultivars of B. napus, Con-II (tolerant) and Oscar (sensitive), were selected after screening and exposed to NiSO4 at 30 ppm at the time of sowing. CA (10 mM) and EDTA (1.5 mM) were applied either alone or in combination with each other after two weeks of Ni treatments. Different parameters like morpho-physiological and biochemical data were recorded after 15 days of chelate application. The results highlighted the successful use of chelating agents (CA and EDTA) not only to ameliorate Ni stress but also to enhance Ni accumulation which is prerequisite for phytoremediation. The basal application of 10 mMCA and 1.5 mM EDTA concentration proved to be effective for the growth of plants. The combination of chelating agents failed to show any synergistic effects.
•Trace elements precipitation endangers the methane yield.•EDTA increased the bioavailability of trace elements.•Reductions of trace elements concentrations were compensated by EDTA.•EDTA showed ...significant positive effects when added to heavily undersupplied substrates.•EDTA addition to biogas processes is advantageous for environmental and economic reasons.
The uptake of essential trace elements by methanogenic bacteria can be obstructed by precipitation in the presence of sulfides and carbonates. The objective of this study was to investigate whether the bioavailability of trace elements, and therefore the methane yield, can be improved through the use of complexing agents. Research showed that the use of EDTA as a complexing agent in the biogas process increases the solubility of essential metals and enhances their bioavailability. If the substrate of a biogas digester has a low content of trace elements, solutions of elements essential for the methanogenic bacteria have to be added to the process. If these metals are complexed with EDTA prior to their supply, the necessary amount can be reduced by up to 75% compared to the non-complexed metals. Therefore, it would be advantageous for environmental and economic reasons to complex trace elements prior to their addition to the biogas process.
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•AC-Fe@Cu shows superiority for efficient, rapid, selective Fe(II)EDTA-NO reduction.•Unique AC@Fe@Cu structure and optimal 1:1 atomic ratio are important.•Rapid electron transfer and ...nascent hydrogen formation are the origin.•Maximization of the roles of Cu as stabilizer and active site also contributes.
Fe(II)EDTA complexing absorption is a promising technology for nitric oxide removal; however, inefficient and slow Fe(II)EDTA regeneration from Fe(II)EDTA-NO reduction and undesirable NH4+ as the major N-containing product are still challenges that should be resolved. This study investigated the performance, kinetics, and product selectivity of Fe(II)EDTA-NO reduction by activated carbon supported bimetallic Fe@Cu composite (AC-Fe@Cu) and unraveled the origin of highly efficient and selective AC-Fe@Cu for Fe(II)EDTA-NO reduction. The reduction efficiency reaches 95.34 % in 30 min, accompanied by 86.78 % N2 selectivity, outperforming most of the reduction systems reported previously. AC-Fe@Cu is resilient at wide pH (3–8), temperature (20–50 °C), and O2 concentration ranges (0–10 %) and maintains high efficiency (76.23 %) after three successive cycles (3 h). Simultaneous reduction of Fe(III)EDTA and Fe(II)EDTA-NO indicates that Fe(II)EDTA-NO reduction is the rate-determining step in the Fe(II)EDTA regeneration process. The bimetal configuration and atomic ratio mediate the reduction efficiency, rate, and N2 selectivity. Unique AC@Fe@Cu structure and optimal atomic ratio of Fe to Cu (1:1) increase the dispersity and provide space proximity and abundant interfaces, which create numerous iron–carbon and iron–copper galvanic cells and promote two-way electron transmission. Fast electron transfer and nascent hydrogen formation contribute to efficient, rapid, and selective Fe(II)EDTA-NO reduction. The maximization of the roles of Cu as stabilizer and active sites for selective N2 formation also contributes. This study sheds light on reduction system design for Fe(II)EDTA regeneration.
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