The removal of heavy-metal ions from wastewater has drawn intense attention, because of their toxicity, bioaccumulation tendency, and persistency in nature. Adsorption is regarded as one of the most ...promising methods, because of its simplicity and efficiency. In the present work, we report the preparation of a novel EDTA-functionalized covalent organic framework (COF) for the removal of heavy-metal ions. First, a COF named TpPa-NO2 was reduced to TpPa-NH2 by using Na2S2O4 as a reductant, and then EDTA dianhydride was grafted onto TpPa-NH2 to obtain TpPa-NH2@EDTA through post-modification. Both the COF morphology and structure remained unchanged after post-modification. The TpPa-NH2@EDTA showed excellent performance in adsorbing different types of heavy-metal ions, such as soft Lewis acid (Ag+, Pd2+), hard Lewis acid (Fe3+, Cr3+), and borderline Lewis acid (Cu2+, Ni2+), and the removal efficiencies are all >85% within 5 min, because of the strong chelation effect of EDTA. The TpPa-NH2@EDTA also showed high adsorption ability in a pH ≥3 environment and have an adsorption capacity of >50 mg/g for the six representative heavy-metal ions. This work provides a new idea for the application of COF materials in the removal of heavy-metal ions from wastewater.
With the expansion of lithium-ion battery market and the awareness of environmental protection, the development of green and sustainable technologies to recycle waste lithium-ion batteries has become ...urgent. Electrodialysis is an emerging green process to recover valuable metals from postconsumer lithium-ion batteries. This study focuses on the separation and recovery of lithium, nickel, manganese, and cobalt from LiNi0.33Mn0.33Co0.33O2 chemistry of lithium-ion batteries using electrodialysis. Prior to the electrodialysis experiment, complexation of ethylenediaminetetraacetic acid (EDTA) with four different metals is assessed using ultraviolet-visible spectroscopy. Using the developed three-stage electrodialysis process, 99.3% of nickel is separated in stage 1 and 87.3% of cobalt is then separated in stage 2 using electrodialysis coupled with EDTA. About 99% of lithium is sequentially separated from manganese in stage 3 using electrodialysis with a monovalent cation-exchange membrane. After the electrodialysis experiment, nickel and cobalt are decomplexed from EDTA at pH below 0.5 and all four metals are recovered with high purity of >99%. Electrodialysis offers a new route to recycle lithium-ion batteries with twofold benefits of providing a secondary source for strategic materials and reducing the number of lithium-ion batteries that are landfilled after they reach their end of life.
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This study investigated the wettability and consistency of various endodontic sealers, both inorganic and organic, and evaluated their sealing ability of root canals using the single-cone obturation ...technique, with and without ethylenediaminetetraacetic acid (EDTA) treatment. Bovine root canals were endodontically prepared and filled in preparation for the dye penetration test with toluidine blue solution. All sealers exhibited contact angles similar to or lower than dentin and displayed superior consistency. Among the sealers, organic sealers used without EDTA treatment showed reduced dye penetration compared to inorganic sealers. However, some inorganic and organic sealers showed dye penetration in the sealer and dentin of root canals subjected to EDTA treatment. In conclusion, the single-cone obturation technique, combined with these endodontic sealers, achieved close contact with root canal dentin due to their wettability and consistency. However, the sealing ability of certain sealers was influenced by EDTA treatment.
Bismuth telluride (Bi2Te3) is an available thermoelectric material with the lowest band gap among bismuth chalcogenides, revealing a broad application in photocatalysis. Unfortunately, its size and ...morphology related to a radio-catalysis property have rarely been explored. Herein, an ethylenediaminetetraacetic acid (EDTA)-assisted hydrothermal strategy was introduced to synthesize polytypic Bi2Te3 nanoplates (BT NPs) that exhibit size-dependent radio-sensitization and metabolism characteristics in vivo. By simply varying the molar ratio of EDTA/Bi3+ during the reaction, BT NPs with different sizes and morphologies were obtained. EDTA acting as chelating agent and “capping” agent contributed to the homogeneous growth of BT NPs by eliminating dangling bonds and reducing the surface energy of different facets. Further analyzing the size-dependent radio-sensitization mechanism, larger-sized BT NPs generated holes that preferentially catalyzed the conversion of OH– to ·OH when irradiated with X-rays, while the smaller-sized BT NPs exhibited faster decay kinetics producing higher 1O2 levels to enhance radiotherapy effects. A metabolomic analysis revealed that larger-sized BT NPs were oxidized into Bi(O x ) in the liver via a citrate cycle pathway, whereas smaller-sized BT NPs accumulated in the kidney and were excreted in urine in the form of ions by regulating the metabolism of glutamate. In a cervical cancer model, BT NPs combined with X-ray irradiation significantly antagonized tumor suppression through the promotion of apoptosis in tumor cells. Consequently, in addition to providing a prospect of BT NPs as an efficient radio-sensitizer to boost the tumor radiosensitivity, we put forth a strategy that can be universally applied in synthesizing metal chalcogenides for catalysis-promoted radiotherapy.
The patency of central venous catheters (CVCs) in patients undergoing hemodialysis (HD) is maintained by instilling sodium citrate 4% (SC 4%) locking solution. Alteplase, a thrombolytic agent, is ...administered to restore function if patency is lost.
To compare SC 4% with a new line-locking solution, ethylenediaminetetraacetic acid 4% (EDTA 4%), in terms of CVC patency and alteplase use.
This retrospective chart review included all HD patients who were switched from SC 4% to EDTA 4% locking solution at 2 tertiary HD centres between June and December 2021. Patients were switched to EDTA 4% if they had high usage of alteplase (receiving ≥ 2 doses of alteplase in a 2-week period). For each line-locking agent, HD pump speeds and alteplase use were analyzed over 2 consecutive 12-week periods. Mean serum calcium and ionized calcium values were recorded during each period. A cost analysis was also performed.
A total of 37 HD patients were switched to EDTA 4% during the study period. There was no difference in mean HD pump speed between SC 4% and EDTA 4% (307.7 vs 305.1 mL/min, p = 0.48). The number of catheter-use-days on which alteplase was required declined significantly, from 313 days with SC 4% to 94 days with EDTA 4% (p < 0.001), with an overall cost reduction of 34% ($13 183.21). The decrease in alteplase usage was primarily driven by 1 of the 2 sites. A statistically significant decrease in mean ionized calcium at site 2 (from 1.12 to 1.1 mmol/L, p = 0.037) was noted. As well, an intraluminal interaction between EDTA 4% and serum calcium caused 6 cases of low serum calcium.
This study showed that use of EDTA 4% as a line-locking agent reduced alteplase usage in the CVCs of HD patients while maintaining adequate pump speed (i.e., ≥ 300 mL/min).
Ethylenediaminetetraacetic acid (EDTA) is a chelating agent that binds tightly to metal ions. We found that cAMP response element (CRE)-driven promoter activity by protons was enhanced by EDTA in ...human T-cell death-associated gene 8 (TDAG8)-overexpressed HEK293T cells. The enhancing action by EDTA was also detected by proton-induced cAMP production that is located upstream from the CRE-driven promoter activity even at physiological proton concentration pH7.4. The proton-induced CRE-driven promoter activity was not enhanced by other chelating agents, ethylene glycol tetraacetic acid (EGTA) and sodium citrate. The enhanced CRE-driven promoter activity by EDTA was not attenuated by increasing the extracellular calcium ion concentration. These results indicate that the EDTA-enhancing action may not be due to its chelating action but might rather be another EDTA-specific effect. Enhanced cAMP production by EDTA was also detected in a human leukemia cell line HL-60, in which TDAG8 and OGR1 (ovarian cancer G-protein-coupled receptor 1) were endogenously expressed, suggesting that the medical use of EDTA would influence the physiological and pathophysiological functions of hematopoietic cells.
•EDTA enhanced cAMP production by protons in human TDAG8-overexpressed cells.•EGTA and sodium citrate did not enhance the cAMP production.•EDTA enhanced cAMP production in HL-60 cells.
The aim of this study is 1) to demonstrate the interactions resulting from mixing ethylenediaminetetraacetic acid (EDTA) withsodium hypochlorite (NaOCl) and 2) to monitor the experimental interaction ...after cold plasma energy transferring mimicking physicochemical activation of solutions. Freshly opened pharmaceutical lavage solutions of 5.25% hypochlorite and 17% EDTA were used in experiments. A mixture of 40 ml was prepared using 5.25% hypochlorite/17% EDTA at a 1:1 ratio. The experimental cold atmospheric-pressure plasma jet (APPJ) treatment was performed using a dielectric barrier discharge (DBD) device for mimicking the activation of lavage solutions. pH measurements of the samples were performed. Spectral changes were analyzed with nuclear magnetic resonance spectroscopy, Fourier-transform infrared spectroscopy, and UV-visible spectrophotometry. N-CH2-COOR and N-CH2-CH2-N were observed in EDTA at 4.65 and 2.90 p/min, respectively. The emergence of new signals at 3.70, 3.07, and 2.91 p/min was observed in the mixture of the EDTA and NaOCl. Decreased peak intensities of EDTA were observed in the APPJ treatment groups at 4.65 and 2.90 p/min with no spectral shift. The main findings are that carbon and nitrogen bonds formed on the EDTA molecule at 2357.08 and 2309.10 cm<inline-formula> <tex-math notation="LaTeX">^{\mathrm {-1 {}}} </tex-math></inline-formula>after oxidation with hypochlorite as middle-narrow and mid-wide, respectively. The molecular structure of EDTA is observed to change after the oxidization by hypochlorite. The newly formed peaks attributed to carbon and nitrogen on the oxidized EDTA molecule disappeared after the experimental APPJ application. The obtained absorbance maxima in the APPJ treatment are in the characteristic region for the <inline-formula> <tex-math notation="LaTeX">\pi </tex-math></inline-formula>-<inline-formula> <tex-math notation="LaTeX">\pi ^\ast </tex-math></inline-formula> transitions. Within the limitations of an in vitro study, the findings of the study demonstrated that the subsequent molecule occurred by the oxidization by hypochlorite or activated hypochlorite is different from each other and also is different from the characteristic structure of EDTA. Experimentally activated hypochlorite by APPJ might have caused the molecular electronic transitions of EDTA.
Boyalar ve ağır metaller, artan çevresel kaygıların tipik kirleticileridir. GO ve GO-EDTA yapılarının sulu çözeltiden TFT boya ve Co (II) metal iyonu giderimi için ideal adsorbanlar olduğu ...belirtildi. pH, zaman, farklı konsantrasyon aralığı ve farklı tuzların etkisi gibi çözelti koşullarının boya ve ağır metal iyonu giderimi üzerindeki etkileri araştırıldı. Farklı tuzların varlığında TFT adsorpsiyonunda değişiklik olmazken, Co (II) iyonunun adsospsiyonunda, katyonların rekabetinin etkisinden dolayı, belirgin düşüş gözlendi. İzoterm modellerinden Langmuir izoterm modelini takip eden adsopsiyon işleminin maksimum adsorplama kapasiteleri (qM) GO ve GO-EDTA üzerine sırasıyla; TFT boyası için 389,3178mg g-1 ve 1009,5300mg g-1, Co (II) iyonu için 736,9153mg g-1ve 1304,3525mg g-1‘dir (pH=7, t=150 min.,298 K).Kinetik veriler yalancı ikinci derece (PSO) modeline oldukça iyi uymaktadır. Partikül içi difüzyon ve Boyd'un modeline göre, adsorpsiyon kinetiği esas olarak sıvı film difüzyonu tarafından kontrol edildiği ve ayrıca partikül içi difüzyondan da etkilendiği belirlendi. Desorpsiyon grafiğinde, oldukça iyi TFT boya desorpsiyonu gözlemlenirken, Co (II) iyonunun desorpsiyonundaki düşüşün nedeni EDTA yapısında bulunan –COONa uçlarında iyon değişimi neticesinde oluşan bağın kuvvetli olmasıyla açıklanabilir. TFT boya molekülünde bulunan benzen halkaları ile GO ve GO-EDTA yapısında bulunan benzen halkalarının π-π etkileşimine girdiği, yapı üzerindeki fonksiyonel gruplarla hidrojen bağı yapması ve karboksilik asit uçlarında iyon değişimi neticesinde elektrostatik etkileşim yapması Co (II) ve TFT’nin adsorpsiyonunda etkili olmuştur. Sonuç olarak, GO ve GO-EDTA nanomalzemeleri sulu çözeltiden organik ve inorganik kirleticilerin arıtımı için geleneksel adsorbanların yerine, gelişmiş adsorbanlar olarak etkin bir şekilde uygulanabileceğini göstermektedir.
Heavy metal ions are considered as one of the major water pollutants, revealing health hazards as well as threat to the ecosystem. Therefore, investigation of most versatile materials for the ...sensitive and selective detection of heavy metal ions is need of the hour. Proposed work emphasizes the synthesis of conducting polymer and carbon nanotube nanocomposite modified with chelating ligand for the detection of heavy metal ions. Carbon nanotubes are having well known features such as tuneable conductivity, low density, good charge transport ability, and current carrying capacity. Conducting polymers are the most reliable materials for sensing applications due to their environmental stability and tuning of conductivity by doping and de-doping. Formation of nanocomposite of these two idealistic materials is advantageous over the individual material, which can help to tackle the individual limitations of these materials and can form versatile materials with ideal chemical and electrical properties. Chelating ligands are the most favorable materials due to their ability of complex formation with metal ions. The present work possesses a sensing platform based on conducting polymer and carbon nanotube nanocomposite, which is stable in various aqueous media and possess good charge transfer ability. Chelating ligands played an important role in the increased selectivity toward metal ions. Moreover, in present investigation Ethylenediaminetetraacetic acid (EDTA) functionalized polypyrrole (Ppy) and single walled carbon nanotubes (SWNTs) nanocomposite was successfully synthesized by electrochemical method on stainless steel electrode (SSE). The electrochemical detection of Pb(II) ions using EDTA-Ppy/SWNTs nanocomposite was done from aqueous media. Cyclic voltammetry technique was utilized for the electrochemical synthesis of Ppy/SWNTs nanocomposite. Ppy/SWNTs nanocomposite was further modified with EDTA using dip coating technique at room temperature. The EDTA-Ppy/SWNTs modified stainless steel electrode (SSE) exhibited good sensitivity and selectivity toward heavy metal ions Pb(II). Detection limit achieved for Pb(II) ions was 0.07 μM.
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