Concentrations Of Ethylenediaminetetraacetic Acid Research Articles

Relationships Between Geochemical Parameters (pH, DOC, SPM, EDTA Concentrations) and Trace Metal (Cd, Co, Cu, Fe, Mn, Ni, Pb, Zn) Concentrations in River Waters of Texas (USA)

Water samples from eight major Texas rivers were collected at different times during 1997–1998 to determine the dissolved and particulate trace metal concentrations, expected to show differences in climate patterns, river discharge and other hydrochemical conditions, and human activities along the different rivers. Specifically, two eastern Texas rivers (Sabine, Neches) lie in a region with high vegetation, flat topography, and high rainfall rates, while four Central Texas rivers (Trinity, Brazos, Colorado, and San Antonio) flow through large population centers. Relatively high dissolved organic carbon (DOC) concentrations in the eastern Texas rivers and lower pH led to higher Fe and Mn concentrations in river waters. The rivers that flow through large population centers showed elevated trace metal (e.g., Cd, Pb, Zn) concentrations partly due to anthropogenically produced organic ligands such as ethylenediaminetetraacetic acid (EDTA) present in these rivers. Trace metal levels were reduced below dams/reservoirs along several Texas rivers. Statistical analysis revealed four major factors (suspended particulate matter [SPM], EDTA, pH, and DOC) that can explain most of the observed variability of trace metal concentrations in these rivers. SPM concentrations directly controlled particulate metal contents. Variation in pH correlated with changes of dissolved Co, Fe, Mn, and Ni, and particulate Mn concentrations, while DOC concentrations were significantly related to dissolved Fe concentrations. Most importantly, it was found that, more than pH, EDTA concentrations exerted a major control on dissolved concentrations of Cd and Zn, and, to a lesser extent, Cu, Ni, and Pb.

Characterization of quinolone resistant genes and control of qnrB transfer by Potentox in clinical isolates

ObjectiveThe objective of the present study was to analyze the presence of qnr genes among different clinical isolates and, subsequently, antibacterial activity of drugs was tested against all of the clinical isolates. Next, we examined the effect of different concentrations of ethylenediaminetetraacetic acid (EDTA) and half of minimum inhibitory concentration (MIC) of drugs on conjugation. MethodsAnalysis of the presence of qnr genes (qnrA, qnrB and qnrS) was done using previously reported primers by polymerase chain reaction. The antibacterial activity of all drugs was determined by MIC and antimicrobial susceptibility (AST) according to the Clinical and Laboratory Standards Institute guidelines (CLSI, 2009). Conjugation was carried out according to the broth mating method. ResultsThe qnrA gene was detected in Acinetobacter baumannii and Citrobacter braakii, whereas qnrB gene was found in Escherichia coli, A. baumannii, C. braakii, Pseudomonas aeruginosa and Klebsiella pneumoniae. However, qnrS was not detected in any of the clinical isolates. The results revealed that Potentox has potential antimicrobial activity against all of the clinical isolates compared to other drugs. Conjugal transfer of qnrB gene from donor to recipient was inhibited at 10 mM EDTA. Similarly, when various drugs at half of MIC were evaluated on conjugation, interestingly, only Potentox could inhibit conjugal transfer of qnrB gene, whereas rest of the drugs failed to inhibit conjugation. ConclusionPotentox has enhanced in vitro antibacterial activity compared to other drugs against quinolone resistant clinical isolates. 10 mM EDTA effectively prevents the conjugal transfer of qnrB gene from donor to recipient. When the same concentration of EDTA was used as a solvent for Potentox, it has again inhibited the conjugal transfer of qnrB gene from donor to recipient. Therefore, inhibition of conjugation can be a novel antimicrobial approach to combat spreading of antibiotic resistance which can be achieved only with Potentox the novel antibiotic adjuvant entity (US patent - US8178501B2).

EDTA in environments subjected to disposal of dairy effluent from processing plants

The presence of Ethylenediaminetetraacetic acid (EDTA) in environments related to the disposal of dairy effluent has been investigated. An HPLC-UV analytical method was used to determine concentrations of EDTA in soil, surface and ground waters. Method detection limits were 1.5 mg/kg (dry weight) for soil, 1 µg/L for surface water and 2 µg/L for groundwater. A quasi one-dimensional vertical mixing model and a numerical simulation of the hydrodynamic processes (the 3DD hydrodynamic model) were applied to simulate the dispersion of EDTA discharged from a large-scale dairy factory into a relatively small river. Based on the modelling results, large volumes of dairy wastewater discharged into the local river had no significant effects on the concentration of EDTA. Analytical results of EDTA in soil and groundwater indicated that there was no concern about the irrigation of dairy sludge onto pasture land. EDTA was, however, detectable in the soil and groundwater, and heavy metals appear to be transported into the groundwater with EDTA chelates in the pasture area irrigated by the dairy wastewater over periods of time.

Spectrophotometric determination of EDTA in aqueous solution through ferroin formation using sodium sulfite as the reducer

This paper presents a simple, easy and reliable method for determination of EDTA (ethylenediaminetetraacetic acid) in aqueous system. Using EDTA chelating with ferric irons, an excessive amount of Fe3+ was added to EDTA solution, and Fe3+ in excess was reduced by addition of a Na2SO3 solution, the outcome ferrous ions were then reacted with 1,10-phenanthroline monohydrate (PTM) to form ferroin, a color developing reagent. The absorbance of the ferroin was determined using spectrophotometry, from which EDTA concentration was obtained. The method was tested for interferences and applied to determination of trace amount EDTA in its degradation by ozone oxidation, and the result compared with those from high-performance liquid chromatography. It was revealed that a low limit of 1.4μM for EDTA concentration detection was achieved with a high correlation coefficient of 0.999 combined with a low relative standard deviation of 0.6%. In contrast to all reported processes, where ferric ions in excess have to be separated from those chelated with EDTA prior to their reduction followed by interaction with PTM and spectrophotometric determination, the key merit of the present method is that EDTA concentration is determined without need of ferric separation, rendering the present process very easy. The method is also characterized by low cost, high precision and high reproducibility at the same time.

Europium interaction with a vault backfill at high pH

AbstractBatch experiments have been used to assess the sorption properties of a potential cementitious repository backfill, NRVB (Nirex reference vault backfill), using Eu3+as a model trivalent radionuclide and ethylenediaminetetraacetic acid (EDTA) as a competing ligand. The NRVB is an effective scavenger of Eu from solution, with most sorbed within minutes onto the crushed material and less than 1.5% remaining in solution after one day (Rdvalues in the range 0.3–2.4 × 104l kg−1). Ultrafiltration showed that nearly all of this remaining Eu (>94%) is attached to NRVB derived colloids or particulates that are mainly retained by a 100 kDa ultrafilter. High concentrations of EDTA (>0.01 M) reduced the extent of sorption at apparent equilibrium. The addition of EDTA to a pre-equilibrated system of Eu3+and NRVB resulted in a temporary suspension of some Eu, but this very quickly returned to the solid phase. There is some irreversibility in these systems, with EDTA able to prevent removal of Eu(III) from solution, but unable to bring it back into solution under the same conditions.

Excessive EDTA induces morphologic changes in bone marrow smears that mimic specific features of dysplasia

The WHO 2008 guidelines recommend that bone marrow (BM) slides for the morphological assessment of dysplasia should be made from freshly obtained BM specimens, and that specimens exposed to anticoagulants for more than two hours are unsatisfactory. However, BM aspirates may be exposed to excessive concentrations of anticoagulant, due to underfilling of the tube or inadequate mixing of the specimen. Here, we document the morphologic changes in BM smears resulting from exposure to excessive concentrations of ethylenediaminetetraacetic acid (EDTA). Subjects with normal morphology in BM smears without anticoagulant were studied. Smears without anticoagulant and smears made from BM stored in excessive EDTA for 2 h at room temperature were stained with May-Grünwald Giemsa, and cell morphology was evaluated microscopically. Neutrophil and megakaryocyte size were measured using a calibrated microscope eyepiece graticule. Excessive EDTA concentrations induced progressive nuclear and cytoplasmic contraction with respective membrane damage, cell smudging and pyknotic nuclei. In the granulocytic and megakaryocytic series, hypolobated neutrophils, small neutrophils and micromegakaryocytes were increased in number. In erythroblasts, nuclear contour irregularities were induced, but in general, artifactual changes did not mimic dyserythropoiesis. With excessive EDTA concentrations, morphologic features of erythroblasts and megakaryocytes were obscured by nuclear and cytoplasmic contraction. Excessive EDTA induces morphologic changes in BM smears that mimic the specific dysplastic features of hypolobated neutrophils, small neutrophils, and micromegakaryocytes. BM aspirates should be collected into an appropriate concentration of EDTA to minimize such artifacts.

English

Pseudomonas aeruginosa is an opportunistic bacterium which has been shown to have multi-drug resistance against fluoroquinolones, β-lactams, and aminoglycosides. In this investigation, we studied the effect of different concentrations of ethylenediaminetetraacetic acid (EDTA) on MexA-MexB-OprM efflux pump and subsequent changes in susceptibility and expression. Next, we examined, the expression of mexAB gene following treatment with half of minimum inhibitory concentration (MIC) of drugs. Our results revealed that 10 mM EDTA significantly reduced MIC of all drugs; moreover, the higher reduction (8 fold) was observed with CSE1034. MexA and MexB expression was down regulated at 2.93 and 3.21 fold, respectively with 10 mM EDTA. When the same concentration of EDTA was incorporated with drugs, the CSE1034 down regulates 5.64 and 5.94 fold expression of mexA and mexB, respectively. Moreover, meropenem treated groups exhibited 2.63 and 3.12 fold down regulation in the expression of the genes. However, treatment with piperacillin plus tazobactam, amoxicillin plus clavulanate, cefoperazone plus sulbactam and imipenem plus cilastatin did not produce changes in the expression of MexAB-OprM. Hence, CSE1034 could be one of the best choices to treat infections caused by microorganisms that overexpressed MexAB-Opr-Mas compared to other drugs. Furthermore, use of EDTA disodium at appropriated concentrations can be regarded as a safe strategy to fight against the menace provided by the efflux pumps.   Key words: Amoxicillin plus clavulanate, CSE1034, ethylenediaminetetraacetic acid(EDTA), efflux pump, meropenem, Pseudomonas aeruginosa, piperacillin plus tazobactam.

Electrochemical preparation of cobalt hexacyanoferrate nanoparticles under the synergic action of EDTA and overoxidized polypyrrole film

The cobalt hexacyanoferrate nanocrystals (Nano-CoHCF) with uniform shape and size were electrochemical deposited on the electrode surface modified with the overoxidized polypyrrole (OPyox) film in the presence of ethylene diamine tetraacetic acid (EDTA). The conceivable effect of EDTA and OPyox film was studied using SEM and electrochemical techniques. The experiment results showed that the nucleation and deposition rate of CoHCF on the electrode surface were controlled by the synergic action of EDTA and OPyox film, which resulted in the formation of uniform Nano-CoHCF. Moreover, some electrodeposition conditions for Nano-CoHCF film had been optimized such as pH, concentration of EDTA, as well as deposition cycles. The resulting modified electrode exhibited excellent catalytic activity and improved stability for the oxidation of hydrazine. Hydrodynamic amperometry was applied for the determination of hydrazine with a linear range of 2.0×10−7 to 1.1×10−5molL−1 and 1.1×10−5 to 4.1×10−4molL−1 with the maximum sensitivity of 2719.5μAmM−1cm−2.

Assessment of genotoxic effect of maleic acid and EDTA: a comparative in vitro experimental study

This study aims to evaluate and compare the genotoxic and apoptotic effect of aqueous solutions of ethylenediaminetetraacetic acid (EDTA) with that of maleic acid (MA) using Chinese hamster lung fibroblast (V79) cells growing in vitro. Exponentially growing V79 cells were treated with various concentrations of EDTA or MA alone for 30min, and genotoxic effect was analyzed by micronucleus as well as comet assays and the type of cell death by apoptotic cell measurements using microscopic and flow cytometric methods. For all the experiments, H2O2 was used as a positive control. Treatment of V79 cells with H2O2 resulted in significantly (P < 0.001) increased micronuclei and levels of DNA damage, whereas, EDTA/MA alone treated cells did not show significant increase of MN frequencies and comet parameters even at their higher concentrations when compared with that of untreated control. V79 cells treated with EDTA/MA for 30min showed a nonsignificant increase in the percentage of apoptotic and necrotic cells at their lower concentrations (0.025 and 0.05% for EDTA and MA, respectively). However, at higher concentrations, i.e., >IC50 (0.1 and 0.5%) for EDTA and MA resulted in increased number of apoptotic and necrotic cells when compared with the untreated group. This study clearly demonstrates that MA and EDTA are not potentially genotoxic agents and MA induced lesser apoptotic/necrotic death than that of EDTA at their clinically relevant doses. MA may have a better clinical acceptability with comparable smear layer removal ability. Hence, the results presented here might be an additional supporting evidence for the use of MA in endodontic practice.

Biofilm Formation by Otopathogenic Strains of Pseudomonas aeruginosa Is Not Consistently Inhibited by Ethylenediaminetetraacetic Acid

Biofilm formation in otopathogenic of Pseudomonas aeruginosa (OPPA) strains is inhibited by ethylenediaminetetraacetic acid (EDTA). EDTA, a widely used chelating agent, has been shown to inhibit biofilm formation in a number of bacteria. Because EDTA may be a well-tolerated reagent to inhibit biofilm formation in cases of suppurative otitis media, we asked if it might be effective in all OPPA strains isolated from chronically infected cholesteatomas. OPPA strains were isolated from patients with infected cholesteatomas. These strains were grown into log phase then were placed in minimal media with varying concentrations of EDTA and incubated for varying periods. Biofilm production was measured colorimetrically by staining with crystal violet. Without added EDTA, most otopathogenic PA exhibited a distinct, but varying, time course of biofilm formation and dissolution with peak production at 12 to 18 hours. Addition of 1 mM EDTA resulted in a delay in the time to peak biofilm formation for most strains, although the amount of biofilm was not decreased. In contrast, some strains showed greater biofilm production with 1 mM EDTA compared with the untreated bacteria. Addition of 10 mM EDTA resulted in a similar effect. Some strains increased biofilm production over controls. Moreover, EDTA inhibited planktonic growth of all OPPA strains at the concentrations studied. Our hypothesis was disproven: EDTA tends to delay biofilm development, although it consistently inhibits planktonic growth. Because EDTA does not cause suppression of biofilm production in all isolates of OPPA, usefulness as an antimicrobial is questioned.

Numerical approach to modelling pulse-mode soil flushing on a Pb-contaminated soil

PurposeSoil flushing can represent a suitable technology in remediation of soils, sediments and sludge contaminated by persistent species (e.g. toxic metal). This paper presents a model specifically developed to evaluate the feasibility of chelating agent-enhanced flushing. The model, here applied to the remediation of real Pb-contaminated soils, was conceived also to simulate an innovative pulse-mode soil flushing technique.Materials and methodsThe soil flushing application was firstly carried out through columns laboratory experiments. Columns were filled with a real Pb-contaminated soil (3,000 mg kg−1 of dry soil) and flushing was operated in a pulse mode with different chelating agent dosages (3 and 4.3 mmol kg−1soil). Experimental results were used to calibrate and validate the developed reactive transport model that accounts for transport of ethylenediamine tetraacetic acid (EDTA) and EDTA–Pb chelate complexes, Pb residual concentration on soil and the reduction in permeability by soil dissolution. Determination of hydrodynamic and hydro-dispersive parameters was carried out through a numerical approach incorporating the use of neural network as interpolating function of breakthrough data obtained by a tracer test.Results and discussionThe EDTA dosage strongly influenced the efficiency in Pb extraction and soil permeability. Cumulative extractions of Pb were found to be 20 and 29 % for the EDTA concentrations of 3 and 4.3 mmol/kg of dry soil, respectively. The soil dissolution caused a significant flow rate decrease, as a consequence of the increase in chelating agent concentration. Therefore the recovery phase duration increased from 738 to 2,080 h. The ability of the model in simulating all the examined phenomena is confirmed by a good fit with experimental results in terms of (a) soil permeability reduction, (b) eluted Pb and (c) residual Pb in the soil.ConclusionsResults highlighted as the model, supported by a preliminary and careful characterization of the soil, can be useful to assess the feasibility of the flushing treatment (avoiding soil clogging) and to address the choice of the operating parameters (flow rate, chelating agent dosage and application method). On the basis of the present research results, a protocol is suggested for in situ soil pulse–flushing application.

Preventive effect of ethylenediaminetetraacetic acid on Escherichia coli-induced acute bacterial cystitis in mice

Objective To evaluate the effect of different concentrations of ethylenediaminetetraacetic acid (EDTA) in the prevention of Escherichia coli-induced acute bacterial cystitis in mice.Methods Ninty-six female Kunming mice were randomly divided into 4 groups:EDTA-1,3,5,7 groups.An acute bacterial cystitis model was established.The injury of bladder epithelium and the expression levels of interleukin-6 (IL-6) and granulocyte colony-stimulating factor (G-CSF) were analyzed.Results Less injury was observed in each EDTA peffusion sub-group than in PBS sub-group,the degree of injury and the expression level of inflammatory factors were decreased in the PBS,0.2 mmol/L EDTA,1.0 mmol/L EDTA,5.0 mmol/L EDTA sub-groups consecutively,and the 5.0 mmol/L EDTA sub-group had the best prevention effect (P＜0.05).Among the EDTA-1,3,5,7 groups,EDTA-1 had the best and EDTA-7 had the worst effect of prevention ( P＜0.05).Conclusion EDTA can prevent acute bacterial cystitis induced by Escherichia coli effectively. Key words: Ethylenediaminetetraacetic acid; Escherichia coli; Bladder epithelium; Membrane protein

Effect of Ethylenediaminetetraacetic Acid on Root Fracture with Respect to Concentration at Different Time Exposures

IntroductionThe objective of this study was to evaluate the effect of ethylenediaminetetraacetic acid (EDTA) on root fracture with respect to various concentrations at different time exposures. MethodsA total of 48 mandibular incisors were selected. Eight nonprepared roots were selected as a negative control. The remaining 40 specimens were instrumented with rotary files and randomly assigned to one of the following groups for final irrigation: (1) 10 mL distilled water for 10 minutes (positive control); (2) 10 mL of 17% EDTA for 1 minute + 10 mL of 1% NaOCl for 1 minute; (3) 10 mL of 5% EDTA for 1 minute + 10 mL of 1% NaOCl for 1 minute; (4) 10 mL of 17% EDTA for 10 minutes + 10 mL of 1% NaOCl for 1 minute; (5) 10 mL of 5% EDTA for 10 minutes + 10 mL of 1% NaOCl for 1 minute. Thereafter, the root canals were filled by using AH26 root canal sealer with a single-cone technique. The specimens were loaded vertically at 1 mm/min crosshead speed until vertical root fracture occurred. Results were evaluated statistically with 1-way analysis of variance and Student's t test. ResultsStatistically significant differences were detected among the groups (P < .05). The highest mean fracture resistance was obtained from the group treated with 5% EDTA for 10 minutes. This is about 2 times more than the weakest mean fracture resistance, which was obtained from the 17% EDTA-10 minute group. ConclusionsThe fracture resistances of endodontically treated roots were found to be differently affected by the various concentrations of EDTA at different time exposures.

Adsorption of Cd to natural biofilms in the presence of EDTA: effect of pH, concentration, and component addition sequence

Both dissolved organic matters (DOM) and natural biofilms are important substances in controlling the behavior of trace metals in natural aquatic environments. In this study, ethylenediaminetetraacetic acid (EDTA) was selected as a typical DOM to investigate the effect of DOM on the adsorption of trace metals to the biofilms in natural waters. The adsorption of Cd to biofilms, including adsorption isotherm at a fixed pH (pH = 6.0) and pH-edge adsorption (pH ranging from 4.3 to 9.0) with different adsorption sequences, was determined without EDTA and in the presence of EDTA ([EDTA] = 0.5 μmol/L for isotherms measurement and [EDTA] = 0.5 and 2.0 μmol/L for pH-dependent adsorption). The presence of EDTA generally decreased the adsorption of Cd, and the effect was determined by solution pH, concentration of EDTA, and adsorption sequence. Higher concentration or higher pH usually resulted in a more significant decrease. The influence of adsorption sequence on the effect of EDTA was insignificant in lower pH range, while the adsorption usually decreased in the order of Cd only adsorption > Cd first adsorption > EDTA first adsorption ≈ simultaneous adsorption in higher pH range. The effect of EDTA could be attributed to the conversion of Cd speciation, the competition with the biofilms for Cd, and the dissolution of Mn oxides from the biofilms. EDTA affected the adsorption of Cd to natural biofilms, and the effect could be fairly significant. The role of Mn oxides in determining the behavior of trace metals might be underestimated.

Micro-tensile bond strength of adhesives to pulp chamber dentin after irrigation with Ethylenediaminetetraacetic acid

Aim:The aim of this study was to evaluate the influence of different concentrations of Ethylenediaminetetraacetic acid (EDTA) solution on adhesion, that is, the bond strength of the different adhesive systems, to the pulp chamber dentin.Materials and Methods:Recently extracted, sound, human, third molars were cut horizontally to expose the pulp horn. The roof of the pulp chamber and pulp tissue was removed. The teeth were then divided into five main groups. The teeth in each group were treated as follows: group 1, irrigated with saline; group 2, with 5% EDTA for 5 minutes; group 3, with 15% EDTA for 5 minutes; group 4, with 17% EDTA for 5 minutes and group 5, with 19% EDTA for 5 minutes. Treated specimens were dried and divided into 2 subgroups for adhesives; bonded with a total-etching adhesive (Adper Scotchbond Multi-purpose - ASB) or a one bottle of self-etch adhesive system (Clearfil S3 Bond – CS3). After the bonding procedure and composite restoration, teeth were sectioned and dentin sticks were obtained from each group for micro tensile testing (n = 10). Micro tensile testing was performed and scanning electron microscope (SEM) photographs were taken for each irrigated group.Results:In the ASB group, saline showed statistically higher bond strength values at the different concentrations of EDTA, while the micro-tensile bond strengths of the different concentrations of EDTA were not statistically different. In the CS3 group, saline and 5% EDTA showed statistically higher bond strength values than 17% and 19% EDTA, while the micro-tensile bond strengths of 15% EDTA compared to saline and 5% EDTA and 15% EDTA compared to 17% EDTA and 19% EDTA, were not statistically different.Conclusion:This study showed that EDTA irrigation can affect the bond strength of adhesive systems on pulp chamber lateral walls. Clinically, low EDTA concentrations can be recommended if self-etch adhesives have been selected.

Effect of EDTA concentration on the physical and optical properties of Cds thin films

AbstractApplication of ethylenediamine tetraacetic acid (EDTA) in the chemical bath solution to enhance the physical and optical properties of chemical bath deposited CdS film was realised. The observed beneficial effect on the crystallisation of CdS crystallites in the bath solution followed by deposition on glass substrates reduces the amorphousity and enhances the crystallinity of the film. The optical transparency of the film attains a maximum of 80% over the wavelength range of 650–1100 nm for the film deposited from EDTA‐added solution having the concentration of 0.006 mol/L. Also, the observed intensity of the characteristic photoluminescence emission was found to be dependent on the concentration of EDTA in the bath solution. © 2011 Canadian Society for Chemical Engineering

Electrochemical properties of nano-sized Li 3V 2(PO 4) 3/C composite powders prepared by spray pyrolysis from spray solution with chelating agent

Li 3V 2(PO 4) 3/C nanoparticles are prepared by spray pyrolysis. Particles formed from spray solutions containing citric acid and ethylenediaminetetraacetic acid (EDTA) as chelating agents are large and hollow with thin walls. The optimum concentrations of citric acid and EDTA are each 0.1 M. Powders subsequently treated at 700 °C under a reducing atmosphere have particles of single phase, monoclinic Li 3V 2(PO 4) 3. The Li 3V 2(PO 4) 3/C powders contains 14.9 wt% carbon. The hollow structures are easily pulverized into nanoparticles by simple milling process. However, Li 3V 2(PO 4) 3 powder formed from spray solution without chelating agent has larger, aggregated structures. Both powders’ charge curves show four plateaus at ca. 3.62, 3.70, 4.08 and 4.55 V. The initial discharge capacities of the Li 3V 2(PO 4) 3/C powders at constant current densities of 0.1, 1 and 3 C were 147, 122 and 86 mAh g −1, respectively. The capacity retention of the Li 3V 2(PO 4) 3/C nanoparticles at a high current density of 1 C after 100th cycle was 78%.

A modified electroless route to monodisperse and uniform nickel nanoparticle

Monodisperse and uniform nickel nanoparticles with an average diameter of ∼30 nm were synthesized through a modified electroless route in which nickel hydroxide (Ni(OH) 2) colloid, H 2O/ethylene glycol (EG) mixing solution, and sodium hypophosphite were used as Ni source, solvent, and reducing agent, respectively. Different from the conventional electroless process, only a trace concentration of complexing agent, ethylenediaminetetraacetic acid (EDTA), was used in this route. At the optimum H 2O/EG volume ratio, monodisperse nickel nanoparticles of high crystallinity were obtained. The presence of trace concentrations of EDTA is necessary for uniformity of the synthesized nickel nanoparticles. The formation process is discussed based on the experimental results.

A Metal‐Free Approach Based on Graphene Oxide‐Modified Electrode for Monitoring the Photoelectrocatalytic Degradation of EDTA

AbstractA novel voltammetric method for the sensitive determination of ethylenediaminetetraacetic acid (EDTA) was developed based on a graphene oxide (GO) modified electrode. In acetate buffer solution, GO showed a voltammetric response composed of a sharp anodic peak and a weak cathodic peak. When EDTA was present in the solution, the voltammetric response of GO was suppressed. Under optimum conditions, the response of the GO‐modified electrode was inversely proportional to the concentration of EDTA from 6.0×10−7 to 1.0×10−4 mol/L. Using such a GO‐based voltammetry, the effective photoelectrocatalytic degradation of EDTA over a TiO2 film electrode was evaluated and some influencing factors were investigated.

Induced-phytoextraction of heavy metals from contaminated soil irrigated by industrial wastewater with Marvel of Peru (Mirabilis jalapa L.)

The primary objective of this study was to evaluate the effect of ethylene diamine tetraacetic acid (EDTA) and citric acid (CA) on Mirabilis jalapa L. growth and phytoextraction of heavy metals from the multi-metal contaminated soil. The results showed that the application of CA (5 and 8 mmol/kg) and EDTA (5 mmol/kg) increased plant growth, while when the concentration of EDTA was up to 8 mmol/kg, the shoot biomass significantly decreased relative to the control plants (P &amp;lt; 0.05); it suffered 48.1%, 53.1%, 58.9%, and 78.2% reduction, respectively, compared to CK, CA-5, CA-8, and EDTA-5. EDTA was more effective than CA at increasing heavy metal uptake in aerial parts of the plants, the shoot concentrations of Cd, Cu, Pb, and Zn increased by 0.55, 3.08, 3.28, and 1.0-fold in the 8 mmol/kg EDTA-treated soils relative to the treatment of 8 mmol/kg CA. The maximum of Cd, Cu, and Pb phytoextraction and remediation factor (RF) were found with 5 mmol/kg EDTA treatment. For Zn, 8 mmol/kg EDTA was most efficient in increasing Zn accumulation in aboveground of M. jalapa.