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The well-designed cathodes with 1D chain-like structure exhibit high aspect ratio and low contact resistance, significantly reducing the transport pathway for Zn2+ ions. By in situ polymerizing highly conductive PANI, a reticulated conductive network is formed, effectively suppressing the dissolution of Mn2+ ions. Under the dual function of structural design and protective layer, the full cell achieved a long cycle life of over 20,000 cycles with a capacity decay rate of only 0.026 ‰ per cycle. [Display omitted] • PANI-coated K-doped Mn 3 O 4 nanochain was prepared for the cathode of AZIBs. • K+ doping enhances Mn 3 O 4 conductivity, oxygen vacancies and Zn2+ diffusion. • Chain-like K-Mn 3 O 4 -NCs reduces contact resistance and improve reaction kinetics. • PANI layer mitigates Mn dissolution and suppresses volume expansion. • K-Mn 3 O 4 -NCs@PANI cathode achieves larger capacity and ultralong-term cycle life. Aqueous zinc ion batteries (AZIBs) are promising energy storage solutions due to their high energy density and safety. However, developing cathode materials that offer both high energy density and durability for Zn2+ ions storage remains challenging. Manganese (Mn) oxide-based cathodes have been developed for AZIBs due to their high discharge voltage and desirable capacity, but face challenges like poor conductivity, slow reaction kinetics, and dissolution during cycling. Doping, morphology/structure design, and protective layers are effective for enhancing the structure, conductivity, and electronic properties of Mn-based oxides. A synthetic strategy combining these methods for Mn 3 O 4 cathodes is proposed for AZIBs. K+ ions doping in Mn 3 O 4 (K-Mn 3 O 4) can regulate local electronic structure, induce oxygen vacancies, improve conductivity, and provide more active sites for Zn2+ ions diffusion. Additionally, K-Mn 3 O 4 nanochain (K-Mn 3 O 4 -NCs), with a unique chain-like nanostructure (NCs) and high aspect ratio, synthesized via Mn2+ ions chelation with nitrilotriacetic acid (NTA) and calcination, show reduced interparticle contact resistance, shorter Zn2+ ions diffusion length, and faster reaction kinetics. Meanwhile, the in-situ polymerized polyaniline (PANI) layer on K-Mn 3 O 4 -NCs shields against corrosion (K-Mn 3 O 4 -NCs@PANI), connects 1D K-Mn 3 O 4 -NCs into a continuous conductive network, suppresses volume expansion, and improves stability. Electrochemical analysis shows that K-Mn 3 O 4 -NCs@PANI exhibits higher stability and faster reaction kinetics due to a reduced bandgap, increased oxygen defects, and less coulombic repulsion between Zn2+ ions and Mn oxide hosts. The K-Mn 3 O 4 -NCs@PANI cathode achieved a high capacity of 510 mAh/g at 0.1 A/g and excellent rate capacity of 203.2 mAh/g at 5 A/g. After 20,000 cycles, it maintained a capacity of 90.3 mAh/g at 5 A/g, showing exceptional long-term stability with a minimal decay rate of 0.026 ‰ per cycle. [ABSTRACT FROM AUTHOR]

[Display omitted] • Trace additive effectively extends the cycle life of ZIBs. • The adsorbed NTA molecules reduce the de-solvation energy barrier. • NTA molecules provide a buffer layer to retard dendrite growth. Aqueous Zn-ion batteries (AZIBs) have attracted widespread attention due to their intrinsic safety, cost-effectiveness. However, active H 2 O in the solvated ions [Zn(H 2 O) 6 ]2+ continuously migrate to the Zn surface to trigger hydrogen evolution reaction (HER) and accelerate Zn corrosion. Herein, Zn dendrites and the related by-products have been successfully inhibited by using trace amounts of Nitrilotriacetic acid (NTA). Theoretical research indicates that two carboxyl groups of NTA molecule strongly anchored on the Zn surface and exposed another carboxyl group outside. Due to the violent interaction of carboxyl groups of NTA with H 2 O, the de-solvation energy barrier of solvated Zn2+ ([Zn(H 2 O) 6 ]2+) on the Zn surface was obviously decreased, inhibit the active water splitting. Meanwhile, the preferential adsorption of NTA on the Zn surface increases the thickness of electric double layer EDL and provides a buffer layer to hinder the dendrite growth. Using 0.04 M NTA as additives in 2.0 M ZnSO 4 electrolyte, the cycling lifespan of both Zn||Zn symmetric and Zn||MnO 2 full cells is markedly prolonged. This study provides certain perspectives for trace amounts of electrolyte additives to satisfy the demand of long-cycle life AZIBs. [ABSTRACT FROM AUTHOR]

Enrofloxacin (ENR) is widely used in aquaculture due to its broad-spectrum activity against a large number of pathogenic bacteria. However, ENR exhibits strong adsorption and a low biodegradation rate in the environment. This study proposes a new method for degrading ENR, which combines dielectric barrier discharge (DBD) with advanced oxidation of peroxymonosulfate (PMS, HSO5−) and the use of nitrilotriacetic acid (NTA) combined with Fe(III) activator to improve reaction efficiency. The effects on the degradation efficiency were experimentally investigated by adjusting the internal process parameters and adding coexisting substances. The ESR and free radical scavenging experiments showed that both hydroxyl and sulfate radicals contributed to the degradation of the pollutant ENR. Based on the identified intermediates, and three possible degradation pathways were suggested. And the intermediates were less harmful. In conclusion, the Fe(III)-NTA/PMS/DBD system may be an efficient, environmentally friendly and new technology with development potential. [ABSTRACT FROM AUTHOR]

Abstract In this work, it was found that the presence of nitrilotriacetic acid (NTA) could enhance the elimination of sulfamethoxazole (SMX) significantly in Mn(II)/peracetic acid (PAA) process. NTA firstly complexed with Mn(II) to produce Mn(II)-NTA complex, which could activate PAA producing CH3C(O)O· and Mn(III)-NTA complex. Subsequently, Mn(V) was generated via two-electron transfer between Mn(III)-NTA complex and PAA. According to the results of UV–vis spectrum analysis, scavenging experiments and chemical probe method, organic radicals and Mn(V) were proved to participate in SMX abatement and Mn(V) was the predominant reactive oxidant. Four possible degradation pathways of SMX in Mn(II)/PAA/NTA process including hydroxylation, amino oxidation, bond cleavage and coupling reaction were proposed based on six identified degradation products. Mn(II)/PAA/NTA process worked only in acidic and neutral conditions and the increase in PAA, Mn(II) or NTA concentration could accelerate SMX removal. This study provides a strategy for improving PAA activation by Mn(II) and an insight into SMX degradation mechanism by Mn(II)/PAA/NTA process.

In this work, it was found that the presence of nitrilotriacetic acid (NTA) could enhance the elimination of sulfamethoxazole (SMX) significantly in Mn(II)/peracetic acid (PAA) process. NTA firstly complexed with Mn(II) to produce Mn(II)-NTA complex, which could activate PAA producing CH3C(O)O· and Mn(III)-NTA complex. Subsequently, Mn(V) was generated via two-electron transfer between Mn(III)-NTA complex and PAA. According to the results of UV–vis spectrum analysis, scavenging experiments and chemical probe method, organic radicals and Mn(V) were proved to participate in SMX abatement and Mn(V) was the predominant reactive oxidant. Four possible degradation pathways of SMX in Mn(II)/PAA/NTA process including hydroxylation, amino oxidation, bond cleavage and coupling reaction were proposed based on six identified degradation products. Mn(II)/PAA/NTA process worked only in acidic and neutral conditions and the increase in PAA, Mn(II) or NTA concentration could accelerate SMX removal. This study provides a strategy for improving PAA activation by Mn(II) and an insight into SMX degradation mechanism by Mn(II)/PAA/NTA process. [ABSTRACT FROM AUTHOR]

Fe0-based heterogeneous Fenton process has been increasingly developed for organic pollutants removal. However, the reaction activity of Fe0 catalyst is easily weakened due to the formation of dense oxide layer or the precipitation of iron hydroxides on the surface. Herein, the effect and mechanism of magnetic field (MF), visible light (Vis), nitrilotriacetic acid (NTA) and inorganic salt ions on the Fe dissolution and dimethyl phthalate (DMP) degradation in the Fe0/H2O2 system were investigated. The results showed that the magnetic field (100 mT), NTA and inorganic salt ions effectively enhanced the dissolution of Fe from the surface of iron filings, and visible light significantly accelerated the Fe3+/Fe2+ cycle in the aqueous phase, which promoted the decomposition of H2O2 by Fe2+ to generate •OH and further enhanced the degradation of DMP. DMP was nearly completely degraded within 60 min in the pH range of 3.0–9.0, indicating the MF/Vis/NTA/Fe0/H2O2 system effectively broadened the pH range of Fenton-like system. The iron sand column tests proved that the MF/solar/NTA/Fe0/H2O2 system was effective for the treatment of waste leachate reverse osmosis concentrate as a typical actual high-salt wastewater, in which the removal rates of chemical oxygen demand and humic acid reached 84.5 and 90.6%, and the chromaticity was almost completely removed. Generally, the activation mechanism of Fe0-based heterogeneous photo-Fenton system was set up and an effective method for organic pollutant removal and high-salt wastewater treatment was provided. [ABSTRACT FROM AUTHOR]

AbstractIn this paper, an excellent foaming formula for natural gas well deliquification was developed, which was based on the synthesized dodecyl ethylethanolamine (DEEA), commercially obtained cocamidopropyl betaine (CAPB) and sodium lauryl glutamate (SLG). The foaming properties and liquid unloading properties were studied, which showed that the optimal molar ratio of DEEA/CAPB/SLG ternary complex turned out to be 14:21:15. At a total concentration of 15 mM in the liquid phase, the optimal DEEA/CAPB/SLG mixture exhibited excellent foaming and liquid unloading capability at various conditions of methanol, condensate oil and salts contents and temperatures. At the methanol content of 45%, the foaming efficiency and liquid unloading efficiency of the DEEA/CAPB/SLG mixture were measured to be 100% and 25.5 ± 2.2%, respectively. When the condensate oil content was 10–30%, the liquid unloading efficiency ranged from 18.0 ± 2.1% to 25.0 ± 2.5%, which was much higher than that (8.3 ± 0.9%) obtained without condensate. The presence of salts retarded the performance of the DEEA/CAPB/SLG mixture, however, the addition of a chelating agent, trisodium nitrilotriacetic acid (NTA), to DEEA/CAPB/SLG could enhance the foaming efficiency and unloading performance at a salinity level of up to 41 × 104 mg/L, which might be the highest salt-resistant level of the gas well foaming mixture. The introduction of 10% methanol exhibited a positive effect on the DEEA/CAPB/SLG mixture’s foaming and liquid unloading performance against temperature (up to 90 °C). At 90 °C, the DEEA/CAPB/SLG foam could remove almost all the liquid from the column. [ABSTRACT FROM AUTHOR]

By varying the ratios of ammonium heptamolybdate, nitrilotriacetic acid, and 2-aminoethanol, a concentrated solution of the molybdenum complex was obtained, which is stable during long-term storage and does not cause the formation of a solid precipitate. In an aqueous solution, 2-aminoethanol replaces ammonium groups in ammonium heptamolybdate, giving mixed ammonium-amine derivatives (NH4)n(NH3CH2CH2OH)6–n[Mo7O24], which induce solution instability and precipitation. Ammonium cations in the HMA molecule can be completely replaced by 2-aminoethanol cations when carrying out the reaction in an aqueous medium with a sixfold molar excess of 2-aminoethanol to obtain the hexaamine derivative (NH3CH2CH2OH)6[Mo7O24]. In the ternary system ammonium heptamolybdate–nitrilotriacetic acid–2-aminoethanol, the formation of highly soluble triammonium [trioxo(nitrilotriacetato)molybdate] hydrate (NH4)3[MoO3L]∙H2O (1) occurs, the crystal structure of which was studied by X-ray diffraction analysis. Using red clover as an example, it was shown that the resulting solution is agronomically more effective in comparison with a solution of a molybdenum complex with (1-hydroxyethylidene)-diphosphonic acid. [ABSTRACT FROM AUTHOR]

Surface modification, encompassing both chemical and physical features, plays a crucial role in fulfilling the requirements of biomaterial applications and also improves their performance. Due to that, this study focuses on the optimization of morphology and functionalization of hydroxyapatite (HAP). For this purpose, hydrothermal growth of HAP on (fluorine tin oxide) FTO is carried out in the presence of calcium and phosphate precursors with Ca/P molar ratio of 1.67:1 in the solution. Trisodium nitrilotriacetic acid (NTA) is used as a chelating additive for the first time during hydrothermal process at temperature between 120 and 180 °C for 16–24 h. Further studies on the effect of NTA concentration on HAP formation indicate that hierarchical structures are formed in the presence of NTA with NTA/Ca molar ratio of 1:1 at temperature between 150 and 180 °C for 24 h, improving crystallinity as temperature increasing. To facilitate the functionalization of HAP, the layer deposited at 180 °C with NTA/Ca molar ratio of 1:1 is peeled using two different reagents, Fluoromount™ and polyvinyl alcohol (PVA). The HAP peeled with PVA shows no relevant morphological changes in SEM images, indicating a successful peeling process using PVA. After that, the HAP powders are functionalized with alendronate (AL) molecules and studied using ATR-FTIR, XPS and BET techniques. Chemical shift of PO 4 3− vibrations and appearance of the new peaks assigned to the –NH 2 group demonstrate successful AL-functionalization. The AL-HAP hierarchical structures fabricated with the aid of NTA can be introduced as multifunctional biomaterials for future bio-applications. [Display omitted] [ABSTRACT FROM AUTHOR]

Asymmetric reduction of the conjugated CC bonds by the old yellow enzymes (OYEs) presents a promising field in the synthesis of chiral chemicals. Nevertheless, few natural OYEs have been applied in large-scale applications due to the requirement of costly NADPH and low operational stability. Herein, a stable and efficient fusion of YqjM from Bacillus subtilis and glucose dehydrogenase (GDH) from Bacillus megaterium was constructed to stereoselectively reduce the conjugated CC bonds in a self-sufficient continuous process. The effects of the enzyme order and different linkers on the fusions were investigated by structural analysis and all-atom molecular dynamics simulation. The best fusion YqjM_G_GDH gave 98% conversion of 100 ​mmol/L 2-methylcyclopentenone with an excellent ee value (>99%) in 3 ​h, while the mixture of individual enzymes only obtained 68% conversion after more than 8 ​h. The improved substrate conversion of YqjM_G_GDH fusion was probably attributed to the increased flexibility of each fused enzyme and the shortening of the diffusion distance of NADPH regenerated. A one-pot process was designed to purify and immobilize the fusion on the Ni2+-nitrilotriacetic acid functionalized magnetic mesoporous silica nanoflowers. The resulting immobilized biocatalyst not only catalyzed the asymmetric reduction of various α,β-unsaturated ketones (20 ​mmol/L) continuously with only 50 ​μmol/L NADP+ to initiate the whole process, but also retained more than 82% of the initial activity after seven cycles, serving as a good candidate for the industrial applications. [ABSTRACT FROM AUTHOR]

Electrochemical redox behaviour of Antimony (Sb) in Nitrilotriacetic acid (NTA) and Tartaric acid (TA) was investigated, owing to its relevance in nuclear, semiconducting and catalysis industry. A quasi-reversible to irreversible nature of Sb reduction was revealed from the type of chelant controlled the Sb availability as dissolved oxygenated species both in electrolyte and in the adsorbed form. Existence of two stable Sb-NTA complexes (denoted as Sb-NTA-a & Sb-NTA-b) was proposed based on the reduction peaks of Sb-NTA complexes observed in cyclic voltammetry. The stability constant of Sb-NTA-a is found to be lower when compared to Sb-TA. A more negative reduction potential compared to -0.3 V for Sb-NTA-b complex, indicates the formation of a stable species. Standard rate constant for Sb reduction evaluated by extended Nicholson method, supported the irreversible Sb reduction, and point towards the difficulty in dissolution of reduced Sb in presence of chelants. NTA acted as a habit modifier, where Sb2O3 acquired an octahedral shape with cubic crystal structure. The presence of NTA, thus modified both the kinetics of Sb reduction and the morphology of Sb deposits. These findings provide additional insights into the active role of chelants used for Sb mitigation both in nuclear and environmental applications.

Objective: A high performance liquid chromatography method was developed to determine EDTA and NTA in water. Methods: The samples were derivatized with ferric chloride, used methanol and a 0.2 mmol/L tetrabutylammonium bromide phosphate buffer solution (pH 2.5) as the mobile phase, separated on a Thermo-C18 (4.6 mm×250 mm) column after gradient elution, detected by HPLC with a diode array detector, and used external standard method for quantitation. Results: The content of EDTA and NTA showed a good linear relationship in the range of 0.1～2.0 mg/L, the correlation coefficients were 0.999 5 and 0.999 2 respectively; The limits of detection were 0.05 mg/L and limits of quantification were 0.1 mg/L; The average recoveries were 93.5%～111.4%; And the relative standard deviations (RSD) were 3.63%～7.39%. Conclusion: This method was convenient, repeatable, sensitive, and practical for the detection of EDTA and NTA.

l -Lactate oxidase has important applications in biosensing and finds increased use in biocatalysis. The enzyme has been characterized well, yet its immobilization has not been explored in depth. Here, we studied immobilization of Aerococcus viridans l -lactate oxidase on porous carriers of variable matrix material (polymethacrylate, polyurethane, agarose) and surface functional group (amine, Ni2+-loaded nitrilotriacetic acid (NiNTA), epoxide). Carrier activity (A c) and immobilized enzyme effectiveness (ɳ) were evaluated in dependence of protein loading. Results show that efficient immobilization (A c : up to 1450 U/g carrier; ɳ : up to 65%) requires a hydrophilic carrier (agarose) equipped with amine groups. The value of ɳ declines sharply as A c increases, probably due to transition into diffusional regime. Untagged l -lactate oxidase binds to NiNTA carrier similarly as N-terminally His-tagged enzyme. Lixiviation studies reveal quasi-irreversible enzyme adsorption on NiNTA carrier while partial release of activity (≤ 25%) is shown from amine carrier. The desorbed enzyme exhibits the same specific activity as the original l -lactate oxidase. Collectively, our study identifies basic requirements of l -lactate oxidase immobilization on solid carrier and highlights the role of ionic interactions in enzyme-surface adsorption. [Display omitted] • l -Lactate oxidase reveals high activity and effectiveness when covalently immobilized on amine agarose carriers. • l -Lactate oxidase adsorbs reversibly to positively charged amine carriers by restoring its specific activity in solution: activity that was not found when immobilized was recovered after desorption of the enzyme. • His-tagged l -lactate oxidase leads to very similar immobilized preparations as native untagged enzyme. • Our results support that immobilized l -lactate oxidase represents a heterogeneous population of carrier-bound enzyme. [ABSTRACT FROM AUTHOR]

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To answer the challenges of using nitrilotriacetic acid (NTAA) as an efficient, recyclable, and durable acidic nanocatalyst, a novel, versatile, engineerable, affordable, eco‐friendly acidic heterogeneous magnetic nanocatalyst has been synthesized with high thermal stability and excellent catalytic efficiency through immobilization of NTTA on the surface of the functionalized magnetite core‐shell. Fe3O4@SiO2‐NH‐NTAA, has been synthesized and presented here. This nanomagnetic catalyst, Fe3O4@SiO2‐NH‐NTAA, was fully identified and characterized through analytical techniques such as FTIR, FESEM, TEM, EDX, elemental mapping, TGA‐DSC, DLS, VSM, and XRD, in addition to theoretical calculations based on DFT/B3LYP/6‐311++G(d, p). Its catalytic capability as well as easy separation, recoverability, and reuseability were examined in the one‐pot preparation of pyrimido[4,5]quinolone‐2,4‐diones under mild conditions, where the high performance of the Fe3O4@SiO2‐NH‐NTAA magnetic nano‐catalyst was proved by excellent reaction yield (>98 %) and the catalyst's recovery efficiency (>98 %). Due to the presence of NTAA's zwitterionic forms in the outermost layer of Fe3O4@SiO2‐NH‐NTAA, this acidic catalyst causes the progress and control of the three‐component reaction in this article well and in the desired direction. [ABSTRACT FROM AUTHOR]

A low- and intermediate-level radioactive waste repository contains various types of radionuclides and organic complexing agents. Their chemical interaction within the repository can lead to the formation of radionuclide-ligand complexes, influencing the limited retention behaviors of radionuclides. This study focuses on the sorption behavior of radionuclides on both engineered (concrete) and natural barriers (sedimentary rock and granite), as well as the prediction of sorption distribution coefficients (Kd) using support vector regression. Batch studies were conducted to determine the K d values for three radionuclides (99Tc, 137Cs, and 238U) under different conditions, including pH, temperature, and the presence of organic ligands (such as ethylenediaminetetraacetic acid, nitrilotriacetic acid, and isosaccharinic acid). The K d values for 238U exhibited a sharp decrease with increasing concentrations of organic ligands. In contrast, the K d values for 99Tc showed only a slight reduction at higher organic ligand concentrations. Meanwhile, the K d values for 137Cs remained relatively unchanged, regardless of the type and initial concentration of organic ligands. This suggests a high level of retention for 137Cs in the rock samples. The support vector regression model with a radial basis kernel function proved effective in predicting the K d values under different experimental conditions. This enhancement in predicting accuracy contributes valuable insights into understanding the sorption processes involved in radionuclide behavior. Overall, this study advances our knowledge of radionuclide behavior on both engineered and natural barriers while providing a reliable prediction tool for estimating sorption distribution coefficients. [ABSTRACT FROM AUTHOR]

Chemically assisted phytoremediation is suggested as an effective approach to amplify the metal-remediating potential of hyperaccumulators. The current study assessed the efficiency of two biodegradable chelants (S,S-ethylenediamine disuccinic acid, EDDS; nitrilotriacetic acid, NTA) in enhancing the remediation of Cd by Coronopus didymus (Brassicaceae). C. didymus growing in Cd-contaminated soil (35–175 mg kg−1 soil) showed increased growth and biomass due to the hormesis effect, and chelant supplementation further increased growth, biomass, and Cd accumulation. A significant interaction with chelants and different Cd concentrations was observed, except for Cd content in roots and Cd content in leaves, which exhibited a non-significant interaction with chelant addition. The effect of the NTA amendment on the root dry biomass and shoot dry biomass was more pronounced than EDDS at all the Cd treatments. Upon addition of EDDS and NTA, bio-concentration factor values were enhanced by ~184–205 and ~ 199–208, respectively. The tolerance index of root and shoot increased over the control upon the addition of chelants, with NTA being better than EDDS. With chelant supplementation, bio-accumulation coefficient values were in the order Cd35 + NTA (~163%) > Cd105 + NTA (~137%) > Cd35 + EDDS (~89%) > Cd175 + NTA (~85%) > Cd105 + EDDS (~62%) > Cd175 + EDDS (~40%). The translocation factor correlated positively (r ≥ 0.8) with tolerance index and Cd accumulation in different plant parts. The study demonstrated that chelant supplementation enhanced Cd-remediation efficiency in C. didymus as depicted by improved plant growth and metal accumulation, and NTA was more effective than EDDS in reclaiming Cd. [ABSTRACT FROM AUTHOR]

Six transmembrane epithelial antigen of the prostate (STEAP) 1-4 are membrane-embedded hemoproteins that chelate a heme prosthetic group in a transmembrane domain (TMD). STEAP2-4, but not STEAP1, have an intracellular oxidoreductase domain (OxRD) and can mediate cross-membrane electron transfer from NADPH via FAD and heme. However, it is unknown whether STEAP1 can establish a physiologically relevant electron transfer chain. Here, we show that STEAP1 can be reduced by reduced FAD or soluble cytochrome b5 reductase that serves as a surrogate OxRD, providing the first evidence that STEAP1 can support a cross-membrane electron transfer chain. It is not clear whether FAD, which relays electrons from NADPH in OxRD to heme in TMD, remains constantly bound to the STEAPs. We found that FAD reduced by STEAP2 can be utilized by STEAP1, suggesting that FAD is diffusible rather than staying bound to STEAP2. We determined the structure of human STEAP2 in complex with NADP+ and FAD to an overall resolution of 3.2 Å by cryo-electron microscopy and found that the two cofactors bind STEAP2 similarly as in STEAP4, suggesting that a diffusible FAD is a general feature of the electron transfer mechanism in the STEAPs. We also demonstrated that STEAP2 reduces ferric nitrilotriacetic acid (Fe3+-NTA) significantly slower than STEAP1 and proposed that the slower reduction is due to the poor Fe3+-NTA binding to the highly flexible extracellular region in STEAP2. These results establish a solid foundation for understanding the function and mechanisms of the STEAPs. [ABSTRACT FROM AUTHOR]

Carbendazim, a systemic fungicide, is being largely used in different sectors like, agriculture, aquaculture, forestry, and food industries. However, due to the presence of stable benzimidazole ring in it leads to the persistence of its toxic residues in the environment. Thus, the detection and quantification of carbendazim residues becomes highly imperative for early risk-assessment and decision-making. Herein, we developed a functionalized multiwalled carbon nanotube with nitrilotriacetic acid trisodium salt monohydrate (f-MWCNT/NTAA Na 3 ·H 2 O) composite-based electrochemical sensor for the detection of carbendazim. From UV spectroscopy and electrochemical measurements, it has been confirmed that the interface aids in the electrocatalytic reaction towards carbendazim due to the inherent thermodynamic feasibility between the analyte and interface, and the same has been tested with density functional theory (DFT). In addition, the developed sensor showed an excellent sensing performance towards carbendazim by eliminating the effect of matrix and by recognizing the active ingredient. The sensor exhibited two distinct wide linear concentration windows in the range of 0.5–25 nM, and 0.1–500 µM with a low detection and quantification limit of 5.54, and 16.80 pM; 10.94, and 33.14 pM, respectively. The f-MWCNT/NTAA Na 3 ·H 2 O modified electrode can be taken for the real-time analysis in water owing to its specificity. [Display omitted] [ABSTRACT FROM AUTHOR]

The use of chelators with high biodegradability is a promising strategy to remove potentially toxic elements (PTEs) from soils by washing. The current study investigated the potential of nitrilotriacetic acid (NTA) to remove Cd from Cd-contaminated soil from Iran (calcareous soil, ICd) and Belgium (acidic soil, BCd). Washing tests were carried out with soils artificially contaminated with 2 levels of Cd (20 and 40 mg kg−1), 4 levels of NTA (0, 2, 5, and 15 mmol L−1), different pHs (4, 7, and 10), and different contact times (20, 40, and 60 min). The results showed that the optimal concentrations of NTA were 5 and 2 mmol L−1 for ICd and BCd, respectively. After using NTA5 compared to NTA0, Cd removal at pH 4, 7, and 10 increased by 1, 76, and 80% in ICd20 and 1, 77, and 81% in ICd40, respectively. These values were 46, 53, and 52% in BCd20 and 32, 64, and 62% in BCd40, respectively, after using NTA2. Also, in the first 20 min of the experiment, 95–100% and 75–80% of the maximum extractable Cd were removed from ICd and BCd, respectively. Moreover, NTA extracted a higher percentage of Ca, Fe, Al, Zn, and Cu from BCd compared to ICd (as an exception, the percentage of Ca extracted at pH 4 was higher in ICd compared to BCd). The results showed that the physical/chemical properties of soils affect the washing efficiency and should be taken into account before selecting the type and dose of chelate to remove metals in a given soil. [ABSTRACT FROM AUTHOR]

Cadmium electroplating was conducted on 30CrMnSiA steel substrate in a cyanide-free bath with amino carboxylic compound as complexing agent. The bath composition and process parameters were as follows: CdCl2⋅2.5H2O 40-50 g/L, NH4Cl 180-220 g/L, nitrilotriacetic acid 60-80 g/L, ethylenediaminetetraacetic acid 20-30 g/L, NiCl2⋅6H2O 50- 300 mg/L (i.e. Ni2+ 12.3-74.1 mg/L), pH 6.5-7.5, room temperature, current density 1 A/dm2, and time 20 min. The effect of mass concentration of Ni2+ on the electrodeposition behavior of cadmium and throwing power of the bath was studied by cathodic polarization curve measurement, cyclic voltammetry, and Hull cell test. The effect of mass concentration of Ni2+ on the appearance, surface morphology, and corrosion resistance of Cd coating was studied by glossiness measurement, scanning electron microscopy, and Tafel plot measurement. The results showed that the addition of a suitable amount of Ni2+ can improve the appearance and corrosion resistance of Cd coating, but slightly affects other properties of Cd coating. It is not recommended to use Ni2+ as an additive alone for cyanide-free cadmium electroplating. [ABSTRACT FROM AUTHOR]

The Fenton system in the presence of nitrilotriacetate (NTA) ligand is studied by DFT approach. The calculations show that complexation of Fe(II) with NTA significantly facilitates the H2O2 activation. The ferric‐hydroperoxo intermediate NTAFe(III)OOH predominantly decays via the disproportionation into NTAFe(II)OH2 and NTAFe(IV)O involving the formation of a μ‐1,2‐hydroperoxo‐bridged biferric intermediate. In this mechanism, the bridged hydroperoxo is reduced by hydroperoxo ligand rather than by Fe(III). On the one hand, the NTAFe(III)OOH is sluggish to undergo hydrogen abstraction; on the other hand, it is a good nucleophile that may perform aldehyde deformylation. The present calculations suggest that both ˙OH and Fe(IV)O are generated in the NTA‐assisted Fenton system. However, the polycarboxylate ligand provides a favorable environment for H2O2 to accumulate around iron ion through hydrogen bonding. This promotes the quenching of Fe(IV)O by H2O2, rationalizing why the Fe(IV)O species is hardly detected in the NTA‐assisted Fenton system. [ABSTRACT FROM AUTHOR]

Purpose: This study aims to investigate the effect of trisodium nitrilotriacetic acid (NTA) on the physical and luminescence emission properties of NaLuF4:Yb, Tm Upconversion (UC) particles and compared with trisodium citrate (CA). Upconversion materials have been remarkably considered in many applications in the past decades. However, the morphology of the UC particles affects their emission properties, depending on the synthesis situation. Design/methodology/approach: The UC particles were synthesized by the hydrothermal method. Properties such as crystal phase, particle morphology, particle size, smoothness and uniformity of particle surface and their emission intensity in the UV–Vis region were studied. Findings: Observations showed that pH is an essential factor in determining the crystalline phase. In addition, quality factors affect the morphology, particle size and surface smoothness of crystalline facets. It was also found that the UC particles synthesized in the presence of trisodium NTA have a much higher emission intensity than those synthesized in the presence of CA. The use of UC particles in security inks to maintain the brand was also investigated. Originality/value: To the best of the authors' knowledge, for the first time, the effect of trisodium NTA as a chelating agent was investigated on morphology and UC intensity of NaLuF4:Yb,Tm phosphor. [ABSTRACT FROM AUTHOR]

This study focused to enhance the cadmium (Cd) phytoextraction efficiency in Solanum nigrum by applying four biodegradable chelants (10 mM)-ethylene glycol tetraacetic acid (EGTA), ethylenediamine disuccinate (EDDS), nitrilotriacetic acid (NTA), and citric acid (CA), when grown in Cd-spiked soil (12 and 48 mg kg−1). Plant height, dry biomass, photosynthetic traits, and metal accumulation varied significantly with Cd and chelant treatments. Cadmium-toxicity resulted in reduction of plant growth and photosynthetic physiology, whereas chelant supplementation alleviated the toxic effect of Cd and increased its accumulation. Tolerance index value increased with addition of chelants in the order: EGTA (1.57–1.63) >EDDS (1.39–1.58) >NTA (1.14–1.50) >CA (1–1.22) compared with Cd (0.46–1.08). Transfer coefficient of root increased with supplementation of EGTA (3.40–3.85), EDDS (3.10–3.40), NTA (2.60–2.90), and CA (1.85–2.29), over Cd-alone (1.61–1.63). Similarly, translocation factor was also increased upon addition of EGTA (0.52–0.73), EDDS (0.35–0.81), NTA (0.38–0.75), and CA (0.53–0.54), compared with Cd-alone (0.36–0.59). Maximum Cd removal (67.67% at Cd12 and 36.05% at Cd48) was observed with supplementation of EGTA. The study concludes that the supplementation of EGTA and EDDS with S. nigrum can be employed as an efficient and environmentally safe technique for reclamation of Cd-contaminated soils. Apart from the selection of a good hyperaccumulator, the choice of chelant (biodegradable/non-biodegradable) is an important aspect for the successful phytoextraction of metals from contaminated soil. We reported for the first time the potential of ethylene glycol tetraacetic acid (EGTA; a biodegradable chelant) in enhancing Cd phytoextraction by Solanum nigrum. Comparative appraisal of metal extraction efficiency of biodegradable chelants at low (12 mg kg−1) and high (48 mg kg−1) Cd dose depicted that EGTA performed better than EDDS, NTA, and CA (other biodegradable chelants). EGTA supplementation did not induce toxicity in plants; rather it improved metal accumulation, morphology, and photosynthetic physiology. [ABSTRACT FROM AUTHOR]

A new supramolecular metal-organic complex, [(DMA)+{Fe(IDA)2}-] (where H2IDA = iminodiacetic acid and DMA = dimethylammonium cation) (1), has been synthesized solvothermally at 90 °C from reaction of ferric(III) chloride hexahydrate with nitrilotriacetic acid (H3NTA) in stoichiometric ratio. The complex was characterized by single crystal X-ray diffraction (SCXRD) along with spectroscopic analyses. During the reaction process, H3NTA is degraded into IDA2- ligand. Structural analysis reveals that 1 is mononuclear and crystallizes in the monoclinic space group C2/c. Within the [Fe(IDA)2]- unit, Fe3+ shows six-coordinate distorted octahedral geometry. The [Fe(IDA)2]- units are connected by strong N1-H1···O4 hydrogen bonds to form anionic 2D supramolecular layers which are further connected by weak C-H···O hydrogen bonds to form a 3D metal-organic supramolecular host (MOSH) structure having 1D supramolecular channels along the crystallographic c-axis. DMA cations are present within the supramolecular channels through N2-H2···O2 hydrogen bonding interactions. Hirshfeld surface analysis and corresponding 2D fingerprint plots indicate that O···H interactions are the major supramolecular interactions present between MOSH and guest DMA cation. DFT calculations reveal that the HOMO and LUMO of the [Fe(IDA)2]- unit are composed of mixed metal-ligand orbitals. Both the absorption and emission spectra of the complex were studied in aqueous phase and the result was correlated with the TDDFT study. [ABSTRACT FROM AUTHOR]

Literature on the use of four chelating agents namely: ethylenediaminetetraacetic acid, nitrilotriacetic acid, diglycolic acid and iminodiacetic acid for the chromatographic separation of micro and macro amounts of rare earth elements was critically reviewed and supplemented with some new unpublished data from our Laboratory. Advantages and disadvantages of ion exchange chromatography both in cation and anion mode as well as ion interaction chromatography techniques, which were used for rare earth elements separation, are discussed. The usefulness of some of the chromatographic systems for micro–macro separations was discussed and demonstrated. The importance of resilience of the separation method to column overloading in some analytical and larger scale separations was emphasized. The methods described in this article might suit well for recovering of individual lanthanides and yttrium from e-waste and other industrial wastes which were fast accumulating in recent years. [ABSTRACT FROM AUTHOR]

This work reports the development of a fluorescence method for the detection of poly(ADP-ribose) polymerase-1 (PARP1), in which a phenylboronic acid-modified fluorescein isothiocyanate dye (FITC-PBA) was used to recognize the formed poly(ADP-ribose) (PAR) polymer. The detection system was designed by conjugating recombinant streptavidin (rSA) with PARP1-specific double-stranded DNA (dsDNA) through streptavidin–biotin interaction. Capture of PARP1 via rSA–biotin–dsDNA allowed for the poly-ADP-ribosylation (PARylation) of both rSA and PARP1 in a homogeneous solution. The resulting rSA–biotin–dsDNA/PAR conjugates were then captured and separated via the commercialized nitrilotriacetic acid–nickel ion-modified magnetic bead (MB-NTA-Ni) through the interaction between NTA–Ni on MB surface and oligohistidine (His6) tag in rSA. The PAR polymer could capture the dye of FITC-PBA through the borate ester interaction between the boronic acid moiety in PBA and the cis-diol group in ribose, thus causing a decrease in fluorescence signal. The PARylation of streptavidin and the influence of steric hindrance on PARylation efficiency were confirmed using reasonable detection strategies. The method showed a wide linear range (0.01~20 U) and a low detection limit (0.01 U). This work should be valuable for the development of novel biosensors for the detection of poly(ADP-ribose) polymerases and diol-containing species. [ABSTRACT FROM AUTHOR]

CuMnO2 nanoflakes have been prepared utilizing a hydrothermal technique with nitrilotriacetic acid as a precipitant. The structure, composition, and morphology are characterized by several techniques. Interestingly, the as-prepared sample delivers 993 mAh g−1 after 300 cycles, excellent rate capabilities (523.2, 293.3, and 156.1 mAh g−1 at 0.5, 1.0, and 2.0 A g−1, respectively) as the anode of a Li-half battery, and a high specific capacitance of 403.3 F g−1 even at 12 A g−1, as well as stable cycling, excellent kinetics, and rate capabilities for supercapacitors applications, which are superior to the single Cu2O or Mn2O3, suggesting a great potential for advanced lithium-ion batteries. [ABSTRACT FROM AUTHOR]

It has proved that the photo-Fenton system modified by polycarboxylic acid is effective against the degradation of organic pollutants. Still, its effect and impact on actual water bodies are not clear. Therefore, this study mainly discussed the effect of actual water elements on the degradation of 2,4-Dichlorophenol in photo-Fenton system modified by Nitrilotriacetic acid (NTA) and its mechanism in pure water. The specific research contents were: the effect of initial concentration of 2,4-Dichlorophenol on its degradation efficiency; the effect of organic matters on the degradation of 2,4-Dichlorophenol; the effect of cations and anions; the effect of different actual water bodies. And the main results were as follows: In the effect of initial concentration, when the concentration of 2,4-Dichlorophenol was 20 mg·L−1, the degradation efficiency was the best (reached 100%). But, with the increase of initial concentration, the degradation efficiency of the system became worse and worse; the coexistence of the same kind of organic compounds can inhibit each other's degradation, and the degradation rate of pollutants in the mixed system was slower than that in the single system; the addition of anions and cations inhibited the degradation of 2,4-Dichlorophenol, and the degradation efficiency varied with the concentration of ions, in which the effect of anions was more complex; the degradation efficiency of 2,4-Dichlorophenol in three kinds of actual water bodies was lower than in deionized water, especially in PPMW. However, the degradation rates of DSTP and NLW were the fastest in the first 20 min. [ABSTRACT FROM AUTHOR]

Molecular immobilization and recognition are two key events for the development of biosensors. The general ways for the immobilization and recognition of biomolecules include covalent coupling reactions and non-covalent interactions of antigen–antibody, aptamer–target, glycan–lectin, avidin–biotin and boronic acid–diol. Tetradentate nitrilotriacetic acid (NTA) is one of the most common commercial ligands for chelating metal ions. The NTA–metal complexes show high and specific affinity toward hexahistidine tags. Such metal complexes have been widely utilized in protein separation and immobilization for diagnostic applications since most of commercialized proteins have been integrated with hexahistidine tags by synthetic or recombinant techniques. This review focused on the development of biosensors with NTA–metal complexes as the binding units, mainly including surface plasmon resonance, electrochemistry, fluorescence, colorimetry, surface-enhanced Raman scattering spectroscopy, chemiluminescence and so on. [ABSTRACT FROM AUTHOR]

Heterogeneous protease biosensors show high sensitivity and selectivity but usually require the immobilization of peptide substrates on a solid interface. Such methods exhibit the disadvantages of complex immobilization steps and low enzymatic efficiency induced by steric hindrance. In this work, we proposed an immobilization-free strategy for protease detection with high simplicity, sensitivity and selectivity. Specifically, a single-labeled peptide with oligohistidine-tag (His-tag) was designed as the protease substrate, which can be captured by a nickel ion-nitrilotriacetic acid (Ni-NTA)-conjugated magnetic nanoparticle (MNP) through the coordination interaction between His-tag and Ni-NTA. When the peptide was digested by protease in a homogeneous solution, the signal-labeled segment was released from the substrate. The unreacted peptide substrates could be removed by Ni-NTA-MNP, and the released segments remained in solution to emit strong fluorescence. The method was used to determine protease of caspase-3 with a low detection limit (4 pg/mL). By changing the peptide sequence and signal reporters, the proposal could be used to develop novel homogeneous biosensors for the detection of other proteases. [ABSTRACT FROM AUTHOR]

In this work, our research group developed usable low-cost superparamagnetic nanoparticles (Fe3O4@NTA) that behave as an excellent energetic material to accelerate the thermal decomposition of ammonium perchlorate (AP). As a synthetic strategy, magnetite nanoparticles (Fe3O4) were coated with nitrilotriacetic acid (NTA) by a simple preparation method. Based on High-resolution transmission electron microscopy (HR-TEM) and vibrating sample magnetometer (VSM) results, Fe3O4@NTA presents a mean diameter of 7.4 nm and superparamagnetic behavior. Chemical characterization by Energy-dispersive X-ray spectroscopy (XPS), Fourier transform infrared (FT-IR), X-ray diffraction (XRD), and thermogravimetric analysis (TGA) provided enough evidence for the presence of a carboxylic acid group and magnetite in the sample. The Fe3O4@NTA catalyst diminishes AP high-temperature decomposition (HTD) to 342 °C and shows a low activation energy (98.02 kJ mol−1). In addition, after the burning rate test, it was observed that these resulting nanoparticles showed an adequate magnetic response against an external magnet. These results are promising for future research, as the opportunity opens to reuse this functional magnetic material in successive catalytic cycles, thus contributing soon to the recycling of raw materials necessary for interplanetary travel. [ABSTRACT FROM AUTHOR]

[Display omitted] • New amino acids derivatives based on nitrilotriacetic acid were synthesized. • Amino acids modification improves their properties as promoters of hydrate formation. • Conversion of 0.164 mol methane/mol water was achieved for phenylalanine derivative. • Aminopolycarboxylic acid structure affects promoting activity of its amides. Solidified natural gas (SNG) is a perspective method for transportation and storing hydrocarbon gases under mild conditions. The aim of this work is to synthesize new compounds based on several amino acids (leucine, methionine, phenylalanine, norleucine, aspartic acid, valine, glutamic acid, norvaline, proline, threonine, alanine, 6-aminohexanoic acid, cysteic acid) with nitrilotriacetic acid (NTA + AA) to improve the efficiency of methane transition from gas phase into hydrate form and compare them with to pure amino acids and sodium dodecyl sulfate (SDS) as well known gas hydrate promoters. According to the results of high-pressure autoclave experiments, 7 NTA + AA samples out of 13 increase methane uptake and water to hydrate conversion better than SDS, which is a well-known effective promoter of hydrate formation, and 12 NTA + AA samples out of 13 have shorter induction times than SDS. In addition, visual observations showed that all the novel promoters synthesized from amino acids and nitrilotriacetic acid do not cause foaming throughout the process of methane hydrate dissociation, which improves the performance of this type of promoter in comparison with SDS. The efficiency of kinetic hydrate promoters at 0.05 wt% concentration by maximum mole consumption of methane decreased in the range of samples: NTA + Phenylalanine > NTA + Glutamic acid > NTA + Leucine > NTA + Norleucine > NTA + Aspartic acid > NTA + Alanine > NTA + Valine > NTA + Norvaline > SDS > NTA + Proline > NTA + Methionine > NTA + Threonine > NTA + Cysteic acid > NTA + 6-aminohexanoic acid. NTA + Phe (nitrilotriacetic acid + phenylalanine) was able to achieve 98.2 % water to hydrate conversion (0.164 mole gas/mole water) at 0.05 wt% concentration, and its induction time was independent of concentration and approximately equal to 30 min, which was about half that of SDS and pure phenylalanine. Thus NTA + Phe can be considered as one of the best promoters of methane gas hydrate formation, which can be used at low concentrations. Modification of amino acids with nitrilotriacetic acid was shown to significantly improve the efficiency of the compounds as kinetic promoters of hydrate formation, both in terms of induction time and methane uptake, compared to pure amino acids, which makes it possible to create more effective eco-friendly non-foaming promoters of methane hydrate formation used at low concentrations. [ABSTRACT FROM AUTHOR]

In recent years, solar photo-Fenton (SPF) processes have gained interest owing to the use of a cost-free and sustainable radiation source and their effectiveness in removing pharmaceuticals, among other Emerging Pollutants (EPs), from wastewater. Especially, when iron complexes are used to work at neutral pH. The stability and biodegradability characteristics make ethylenediamine-N,N-disuccinic acid (EDDS), and nitrilotriacetic acid (NTA) suitable iron complexing agents. In this work, the removal of diclofenac (DCF) and ibuprofen (IBU), two of the most widely used Non-steroidal Anti-Inflammatory Drug (NSAID) for the treatment of pain, at 200 µg L−1 was studied in wastewater using SPF at natural pH, comparing EDDS and NTA as chelating agents for the first time. The main transformation products (TPs) were also monitored. For this purpose, a suitable analytical method using liquid chromatography coupled to triple quadrupole tandem mass spectrometry (LC-QqQ-MS/MS) with Electro Spray Ionization negative mode (ESI-) was applied to determine the pharmaceutical EPs and their main TPs in wastewater. Next, they were confirmed by LC-QTOF-HRMS. DCF was degraded 44 % faster with NTA (t 1/2 53 min) than with EDDS (t 1/2 77 min), although the final removal percentages, including photolysis, were similar (90–93 %). In contrast, IBU removal with EDDS (t 1/2 116 min) was twice as fast as with NTA (t 1/2 231 min), whereas photolysis was ineffective. Twenty TPs were monitored, of which only three were detected because of the low concentration used in this study: DCF-2C (m/z 258.0326), DCF-6B (m/z 310.0040), and IBU-4 (m/z 221.1181). Their behaviour followed a formation-elimination profile, but only the complete oxidation of DCF-6 was achieved. This work focuses on the kinetic aspects and TPs formed, which are useful for improving knowledge for the development of efficient processes to abate organic pollutants in real aqueous matrices. Therefore, more EPs should be thoroughly studied to determine the efficiency of EDDS and NTA as iron-chelating agents and the necessity of implementing the SPF process in WWTPs. [Display omitted] • Ibuprofen removal by direct photolysis was negligible. • Diclofenac (DCF) was degraded 44 % faster with Fe3+-NTA than with Fe3+-EDDS. • QqQ and QTOF analysers were employed for identification and confirmation. • Twenty TPs were monitored, of which only three were detected. • TPs followed a formation-elimination profile, but only hydroxy-DCF was fully oxidised. [ABSTRACT FROM AUTHOR]

Industrial hemp is a valuable fibrous plant with high biomass production for it can survive under variable environmental stresses including heavy metals and is used in a wide range of products. This research work aimed at determining the growth potential of industrial hemp (Cannabis sativa) developed on lead (Pb) contaminated mine soils using various chelating agents viz., ethylenediaminedisuccinic acid (EDDS), ethylenediaminetetraacetic acid (EDTA), citric acid (CA) and nitrilotriacetic acid (NTA) under various concentrations of nitrogen (N) fertilizer such as 0 (control), 50, 150, 250 and 350 kg ha−1. Results indicated that the synergistic effect of chelating agents and rising concentrations of N fertilizer resulted in a linear increase in hemp growth and dry biomass. The chelating agent and N mediated showed better response in the photosynthetic, antioxidative, and osmolytic potential of hemp as compared with control. The concentration of N and Pb plants showed a differential response such as N accumulation was maximum in plant leaf and shoot portions as compared to the roots. In contrast, Pb enrichment was higher in the roots than in the plant's leaves and stems when exposed to varying concentrations of N fertilizer and chelating agents in the soil environment. Biomobilizaiton of Pb in the plant continuum enhanced with the rising N fertilizer levels in the soil. The EDTA showed better phytoextraction potential as compared with the rest of the chelating agents. Hence, findings suggest that the synergistic application of chelating agents and N fertilizer is a far more effective technique that increases the bioavailability of Pb for phytoextraction and decreases Pb-induced oxidative injuries by restricting Pb uptake. [Display omitted] • Hemp crop can be used as a potential soil Pb phytoremediator. • Bioavailability of soil Pb can be enhanced by the EDTA and nitrogen. • Optimal Nitrogen and EDTA increase the translocation of Pb in the hemp. • EDTA and Nitrogen facilitated the improved phytoremediation of Pb by hemp. [ABSTRACT FROM AUTHOR]

Herein, a nanoconfinement strategy was employed to encapsulate nano zero-valent iron (confined-Fe0) for the rapid degradation of sulfamethoxazole (SMX) through a peroxymonosulfate (PMS)-mediated Fenton-like reaction. The confined-Fe0 catalyst was synthesized in situ using a liquid-phase reduction method, incorporating nitrilotriacetic acid (NA) modified carboxylated carbon nanotube (FOC-N-6). Comprehensive experimental analyses and characterizations demonstrated the FOC-N-6 catalyst facilitated rapid electron transfer through the carbon framework and the surface PMS reactive complex (FOC-N-6-PMS*). This process accelerated the Fe(III)/Fe(II) redox cycle and promoted the formation of surface Fe(II) active sites (Fe0-OCNT-COOFe(II)-), which served as dominant adsorption sites for PMS. Density functional theory (DFT) calculations revealed that the confined-Fe0 structure can decrease the adsorption energy (E ads) of PMS on the FOC-N-6 surface. And the FOC-N-6-PMS* facilitated the rapid degradation of SMX through both non-radical and radical pathways. This confined-Fe0 catalytic strategy holds promise as a viable method for controlling emerging contaminants. [Display omitted] • FOC-N-6 exhibited an extraordinary degradation performance for SMX. • Confined-Fe0 facilitated electron transfer through the OCNT and FOC-N-6-PMS*. • The Fe0-OCNT-COOFe(II)- complex acted as the dominant adsorption site for PMS. • Degradation pathways of direct electron transfer and radical were studied using DFT. • Confined-Fe0 exhibited stability both in catalytic performance and air-exposed storage. [ABSTRACT FROM AUTHOR]

The ability to measure the levels of diagnostically relevant proteins, such as antibodies, directly at the point of care could significantly impact healthcare. Thus motivated, we explore here the E-DNA "scaffold" sensing platform, a rapid, convenient, single-step means to this end. These sensors comprise a rigid nucleic acid "scaffold" attached via a flexible linker to an electrode and modified on its distal end with a redox reporter and a protein binding "recognition element". The binding of a targeted protein reduces the efficiency with which the redox reporter approaches the electrode, resulting in an easily measured signal change when the sensor is interrogated voltammetrically. Previously we have demonstrated scaffold sensors employing a range of low molecular weight haptens and linear peptides as their recognition elements. Expanding on this here we have characterized sensors employing much larger recognition elements (up to and including full length proteins) in order to (1) define the range of recognition elements suitable for use in the platform; (2) better characterize the platform's signaling mechanism to aid its design and optimization; and (3) demonstrate the analytical performance of sensors employing full-length proteins as recognition elements. In doing so we have enlarged the range of molecular targets amenable to this rapid and convenient sensing platform.

For nearly three decades, zero-valent iron (ZVI) has been used in wastewater treatment and groundwater and soil remediation. ZVI can degrade contaminants by reactions of adsorption, redox, and co-precipitation. It can also react with oxidants like hydrogen peroxide, persulfate, and ozone to produce highly reactive radicals that can rapidly remove and even mineralize organic contaminants. However, the application of ZVI is also limited by factors such as the narrow pH range and surface passivation. The addition of chelating agents such as nitrilotriacetic acid (NTA), ethylenediaminetetraacetic acid (EDTA), or citrate to the ZVI-based processes has been identified to greatly increase the iron stability and improve the efficiency of contaminant degradation. From the perspective of commonly used organic and inorganic chelating agents in ZVI applications, the review addresses the current status of ligand-enhanced ZVI degradation of organic contaminants, illustrates the possible reaction mechanism, and provides perspectives for further research. [ABSTRACT FROM AUTHOR]

Impregnation solutions for the preparation of NTA-modified CoMo/Al2O3 hydrodesulfurization catalysts were prepared without use of unnecessary and disrupting NH4+ and NO3− ions. The reaction-dissolution took place in the suspension of NTA, CoCO3·xH2O and MoO3 (here DISUSPEN method). The conventional solutions, prepared in the literature using NTA, NH4OH, MoO3 and Co(NO3)2, (here DISAMON method), were neutral or basic. The solid obtained by their drying was partly crystalline. The DISUSPEN solutions were acidic, with pH = 1.0–1.5. The DISUSPEN solids were XRD-amorphous with glass-like appearance. Much less nitrogen-containing emissions is produced during in-situ sulfidation of DISUSPEN catalysts as compared with DISAMON catalysts. Catalysts prepared by the DISUSPEN method are more active in HDS of thiophene than those prepared by the conventional DISAMON method. [ABSTRACT FROM AUTHOR]

In the present work, we prepared three polymer inclusion membranes (PIM), based on polyvinyl alcohol (PVA) as polymeric support and containing three extractive agents: Nitrilotriacetic acid (NTA), Ethylene diamine tetra acetic acid (EDTA) and tris (2-aminoethyl) amine (TREN). The morphology structures of these membranes were determined using different spectroscopical techniques by Fourier-transform infrared spectrometry and scanning electron microscopy techniques. The membranes were used to conduct experiments of oriented extraction processes for the facilitated recovery of Nickel (II) ions from lithium-ion (Li-ion) battery waste. The obtained results allowed to determine the values of different macroscopic and microscopic parameters of paramount importance such as respective permeability (P), initial flux (J0) and apparent diffusion coefficient (D*), constant association (Kass) related to the movement of the substrate through the membrane. The influence of several factors, as the initial substrate concentration and temperature (C0, T) was studied. The results indicate that the different parameters (P, J0, D* and Kass) vary strongly with the temperature of the medium and that of the performances of the used membranes increase with the temperature factor. The activation and thermodynamic parameters (Ea, ΔH#ass and ΔS#, ∆Hth and ∆Hdiss#) were also determined and their values indicate a kinetic control for the mechanism of the studied processes, which explains the high performances of the developed membranes and indicates a mechanism by successive jumps of Nickel (II) ions on fixed sites of the extractive carriers immobilized in the membrane phase. [ABSTRACT FROM AUTHOR]

In this paper, the efficiency and mechanism of using nitrilotriacetic acid(NTA) as a complexing agent to enhance the zero-valent iron(Fe0)/peroxymonosulfate(PMS) system to remove sulfamethazine(SMZ) from water are discussed. Research results show that the addition of NTA increases the soluble iron by 3.05 times, and the decomposition rate of PMS increases from 27% to 62%. Keeping other conditions unchanged and increasing the concentration of PMS to 0.2 mM, the degradation rate reaches the peak, continued increase of PMS concentration will decrease the degradation rate. The degradation rate of SMZ is positively correlated with Fe0 concentration. The effect of different inorganic ions on the degradation of SMZ was investigated. The high concentration of Cl− promoted the degradation effect, and the reaction rate constant of the system is increased by 1.67 times when the Cl− dosing is 10 mM. The PMS/Fe0/NTA system degrades SMZ up to 79.36% in actual water bodies. The degradation of SMZ is mainly by Smiles-type rearrangement, sulfonamide bond breaking, etc. The toxicity test proves that the inhibition rate of luminescent bacteria before and after degradation decreases from 61.86% to 40.47%, with an overall decreasing trend of toxicity. [Display omitted] [ABSTRACT FROM AUTHOR]

The dissolution of Tc(IV), in the form of TcOOH+, in the presence of four different polyamino polycarboxylate (PAPC) ligands was quantified over 89 days. These experimentally determined Tc(IV) solubilities in PAPC ligand solutions were compared to predicted solubilities previously calculated by this group. The PAPC ligands selected for this study were iminodiacetic acid (IDA), nitrilotriacetic acid (NTA), and hydroxyethylethylenediaminetriacetic acid (HEDTA). The presence of each of the PAPC significantly increases Tc(IV) solubility. The solubilities of Tc(IV) after 89 days is 3.4 ± 0.1 µM, 3.9 ± 0.3 µM, and 8.3 ± 0.9 µM in the presence of 10 mM of IDA, NTA, and HEDTA, respectively, and at solutions of ionic strength 0.5 M (NaCl) and pH 2.3. The solubilities agrees with predictive values for IDA, NTA, and HEDTA. The solubility of Tc(IV) in the absence of ligand in solutions of ionic strength 0.5 M (NaCl) and pH 2.3 is 0.7 ± 0.7 µM after 89 days. [ABSTRACT FROM AUTHOR]