Marine Drugs
·
2019
·Vol. 17
·期 8
·438
·
IF 3.772
Xiaoyang Liu,Zixu Wang,Fawen Yin,Yuxin Liu,Ningbo Qin,Yoshimasa Nakamura,Fereidoon Shahidi,Chenxu Yu,Dayong Zhou,Beiwei Zhu
In this study, three synthetic zinc-chelating peptides (ZCPs) derived from sea cucumber hydrolysates with limited or none of the common metal-chelating amino-acid residues were analyzed by flame atomic absorption spectroscopy, circular dichroism spectroscopy, size exclusion chromatography, zeta-potential, Fourier transform infrared spectroscopy, Raman spectroscopy and nuclear magnetic resonance spectroscopy. The amount of zinc bound to the ZCPs reached maximum values with ZCP:zinc at 1:1, and it was not further increased by additional zinc presence. The secondary structures of ZCPs were slightly altered, whereas no formation of multimers was observed. Furthermore, zinc increased the zeta-potential value by neutralizing the negatively charged residues. Only free carboxyl in C-terminus of ZCPs was identified as the primary binding site of zinc. These results provide the theoretical foundation to understand the mechanism of zinc chelation by peptides.Keywords:zinc-chelating peptide;sea cucumber;chelation mechanism
研究领域:
生物化学
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营养学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
MOLECULES
·
2016
·Vol. 21
·期 3
·299
·
IF 2.465
Bo Jin,Rongzong Zheng,Rufang Peng,Shijin Chu
Five new bis(3-hydroxy-4-pyridinone) tetradentate chelators were synthesized in this study. The structures of these tetradentate chelators were characterized by1H-NMR,13C-NMR, FT-IR, UV-vis, and mass spectral analyses. The binding abilities of these tetradentate chelators for uranyl ion at pH 7.4 were also determined by UV spectrophotometry in aqueous media. Results showed that the efficiencies of these chelating agents are dependent on the linker length. Ligand4bis the best chelator and suitable for further studies.Keywords:chelating agent;3-hydroxy-4-pyridinone;uranium;tetradentate chelator
研究领域:
化学
·
环境科学
✓ 已验证
DOI
PubMed
高影响因子
Energies
·
2021
·Vol. 15
·期 1
·153
·
IF 3.004
Erdong Yao,Hang Xu,Yuan Li,Xuesong Ren,Hao Bai,Fujian Zhou
Economical and environmental concerns have forced the oil and gas industry to consider reusing flowback and produced water for fracturing operations. The major challenge is that the high-salinity of flowback water usually prevents its compatibility with several fracturing fluid additives. In this paper, the authors explored an economic and effective method to prepare guar fracturing fluids with different salinity waters. The main research idea was to use chelating agents to mask metal ions, such as calcium and magnesium, that are harmful to crosslinking. Firstly, a complexometric titration test was conducted to measure the chelating ability of three chelating agents. Secondly, through viscosity, crosslinking, and hanging tests, it was verified that the complex masking method could cope with the problem of high-valence metal ions affecting crosslinking. Thirdly, the preferred chelating agent was mixed with several other additives, including thickeners, crosslinkers, and pH regulators, to prepare the novel guar fracturing fluid. The comprehensive performances of the novel fluid system were tested such as temperature and shear resistance, friction reduction, gel-breaking performance, and core damage rate. The results show that the organophosphate chelating agent (i.e., CA-5) had the greatest ability to chelate calcium and magnesium ions. There was a good linear relationship between the dosage of CA-5 and the total molar concentration of calcium and magnesium ions in brine water. The main mechanism was that the chelating agent formed a complex with calcium and magnesium ions at a chelation ratio of 1:5. The test results of the comprehensive performance evaluation indicate that the prepared guar fracturing fluid met the requirements for field application, and the lower the salinity of the flowback water, the more it is economical and effective.Keywords:flowback and produced water;chelating agent;complex masking method;crosslinker;chelation ratio
研究领域:
石油工程
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环境科学
✓ 已验证
DOI
高影响因子
INTERNATIONAL JOURNAL OF FOOD SCIENCE AND TECHNOLOGY
·
2024
·
IF 2.6
Shuaishuai Wei,Jiaying Huo,Jia Lin,Ziwei Zhang,Shijian Dong,Lulu Ma,Shugang Li
Summary In this study, a method to produce iron-chelating peptides derived from egg yolk proteins was developed and optimised. The egg yolk proteins were enzymolysed and ultrafiltered to prepare egg yolk peptide (EYP), and then the EYP was chelated with Fe to produce egg yolk peptide-Fe (EYP-Fe). The optimised mass ratio of peptide to iron, pH, temperature and reaction time were found at 8:1, pH 8.0, 40 °C and 30 min, respectively. The mean particle size of EYP-Fe was 389.2 ± 2.61 nm, and the chelating ratio was 95.38 ± 1.93%. The measurements of FTIR, X-ray photoelectron spectroscopy (XPS) and NMR showed that ferrous ions mainly combined with the amino and carboxyl of EYP to form EYP-Fe. In vitro stability studies have shown that the iron release rate of the EYP-Fe is maintained at around 5% under alkaline conditions, and there is no significant difference in iron release rate under conditions of 30 °C–80 °C; besides, it has a lower iron release rate (18%) in gastrointestinal digestion compared to FeSO 4 (97.93%), indicating that the EYP-Fe has good heat tolerance, alkalinity and digestion tolerance. The above results provide a scientific basis for the use of EYP-Fe derived from egg yolk protein as a potential alternative to iron supplements.
研究领域:
食品科学
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营养学
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化学
✓ 已验证
产品关联
DOI
高影响因子
Minerals
·
2017
·Vol. 7
·期 2
·20
·
IF 2.088
Zhili Li,Feng Rao,Shaoxian Song
To separate one base metal mineral from another by flotation, it is indispensable to identify chemical reagents that specifically interact with the surface metal sites of one mineral or a group of minerals. This work studies the interactions of chelating collectors which offer the best potential for collecting abilities and mineral specificity with a typical refractory oxide mineral (malachite). Zeta potential, adsorption and Fourier transform infrared (FTIR) measurements are applied to differentiate the interactions of salicylaldoxime and salicyl hydroxamate on the malachite surface. Salicylaldoxime and salicyl hydroxamate are of molecular structures that resemble each other, but with different bond distances in the ligand atoms which result in their unusual adsorption behavior and collecting ability. Thus, the flotation of malachite behaves differently with the two chelating collectors. This study might provide useful clues for designing novel collectors in base metal oxide flotations.Keywords:malachite;flotation;chelating collector;adsorption
研究领域:
矿物加工工程
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
NEW PHYTOLOGIST
·
2016
·Vol. 211
·期 2
·658-670
·
IF 7.21
Jian Yang,Ming-Xing Gao,Han Hu,Xiao-Meng Ding,Hong-Wei Lin,Lei Wang,Ji-Ming Xu,Chuan-Zao Mao,Fang-Jie Zhao,Zhong-Chang Wu
Summary Arsenic (As) contamination in a paddy environment can cause phytotoxicity and elevated As accumulation in rice ( Oryza sativa ). The mechanism of As detoxification in rice is still poorly understood. We isolated an arsenate (As(V))-sensitive mutant of rice. Genomic resequencing and complementation identified OsCLT1 , encoding a CRT-like transporter, as the causal gene for the mutant phenotype. OsCLT1 is localized to the envelope membrane of plastids. The glutathione and γ-glutamylcysteine contents in roots of Osclt1 and RNA interference lines were decreased markedly compared with the wild-type (WT). The concentrations of phytochelatin PC 2 in Osclt1 roots were only 32% and 12% of that in WT after As(V) and As(III) treatments, respectively. OsCLT1 mutation resulted in lower As accumulation in roots but higher As accumulation in shoots when exposed to As(V). Under As(III) treatment, Osclt1 accumulated a lower As concentration in roots but similar As concentration in shoots to WT. Further analysis showed that the reduction of As(V) to As(III) was decreased in Osclt1 . Osclt1 was also hypersensitive to cadmium (Cd). These results indicate that OsCLT1 plays an important role in glutathione homeostasis, probably by mediating the export of γ-glutamylcysteine and glutathione from plastids to the cytoplasm, which in turn affects As and Cd detoxification in rice.
研究领域:
植物学
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环境科学
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遗传学
✓ 已验证
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2019
·
IF 8.355
Mu Ding,Lang Chen,Yuwei Xu,Bo Chen,Jie Ding,Rulei Wu,Chao Huang,Yi He,Yongdong Jin,Chuanqin Xia
99 Tc is a β-emitting radionuclide with high fission yield, long half-time and it is urgent to remove Tc from liquid radioactive waste due to its potential toxicity for human. Herein, we presented a viologen-based cationic organic polymer (VBCOP) as a novel adsorbent with cationic sites and functional groups for efficient capture of Re/Tc(VII, IV) from aqueous medium. The results showed that this material could rapidly remove TcO 4 − /ReO 4 − from aqueous solution within 5 min and the maximum sorption capacity for Re(VII) could reach up to 444 mg g −1 , and the distribution coefficient ( K d ) towards Re(VII) and Tc(VII) reached 4.0 × 10 5 and 7.2 × 10 5 mL g −1 , respectively. And more, the adsorption mechanism was also studied by X-ray photoelectron spectroscopy (XPS), Energy dispersive spectrometer (EDS) mapping and Ion chromatography (IC), the results suggested an ion-exchange process in which the Cl − in this material was replaced by ReO 4 − . Additionally, we investigated its adsorption mechanism towards low-valent Re which was prepared by reducing ReO 4 − with NaBH 4 , and the flexible tetraaza macrocycle introduced in the material chelated with Re(IV) was confirmed by X-ray photoelectron spectroscopy (XPS) and Extended X-ray absorption fine structure (EXAFS) analysis. In general, the research exhibits a new sorbent material that can remove both TcO 4 − /ReO 4 − and the low-valent Tc/Re, and provide a new strategy to treat radioactive waste containing Tc with different valences.
研究领域:
放射化学
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
·
2019
·Vol. 27
·期 1
·812-822
·
IF 2.914
Xu Suyun,Yan Ning,Cui Minghao,Liu Hongbo
In this study, ozone-oxidation was used to treat synthetic chemical plating solution containing Cu(II)/Ni(II)-EDTA solution to realize the purpose of decomplexation. The effects of solution pH, initial concentration of Cu(II)/Ni(II)-EDTA, the molar ratio of EDTA to Cu(II)/Ni(II), and the coexistence of Cu(II)/Ni(II) on their removal efficiencies were investigated. The degradation of EDTA-Cu(II) and EDTA-Ni(II) were mainly attributed to OH oxidation, and the removal rates of Cu(II)/Ni(II) depend on the complete decomplexation. The removal rates of Cu(II) and Ni(II) was affected by the pH of solution, and the optimal pH was found to be 7–9; nevertheless, their removal rates can still be up to 90% even in acidic pHs of 3~5. When the molar ratio of EDTA to Cu(II)/Ni(II) increased from 1:1 to 3:1, the kinetics of metal ion removal rate declined from 0.0788 and 0.1139 min -1 to 0.0250 and 0.0271 min -1 . The synergistic effect was found in the Cu(II)/Ni(II) blended system due to the higher catalytic capability and the lower complexation affinity toward EDTA for Ni(II). In summary, ozone oxidation can be considered as an effective technology to realize the complete decomplexation of Cu(II)/Ni(II)-EDTA that contained in chemical plating industry wastewater.
Graphical Abstract
研究领域:
环境科学
·
化学工程
✓ 已验证
DOI
高影响因子
Polymers
·
2017
·Vol. 9
·期 11
·568
·
IF 3.364
Guo Lin,Shixing Wang,Libo Zhang,Tu Hu,Jinhui Peng,Song Cheng,Likang Fu
A new cyanuric-thiosemicarbazid (TSC-CC) chelating resin was synthesized and employed to selectively adsorb Ag+from acid solutions. The effects of acid concentration, initial concentration of Ag+, contact time and coexisting ions were investigated. The optimal acid concentration was 0.5 mol/L. The adsorption capacity of Ag+reached 872.63 mg/g at acid concentration of 0.5 mol/L. The adsorption isotherm was fitted well with the Langmuir isotherm model and the kinetic data preferably followed the pseudo-second order model. The chelating resin showed a good selectivity for the Ag+adsorption from acid solutions. Fourier transform infrared (FT-IR), X-ray diffraction (XRD), Scanning electron microscopy/energy dispersive spectrometer (SEM-EDS) and X-ray photoelectron spectroscopy (XPS) were used to study the adsorption mechanism. The chelating and ionic interaction was mainly adsorption mechanism. The adsorbent presents a great potential in selective recovery Ag+from acid solutions due to the advantage of high adsorption capacity and adapting strongly acidic condition. The recyclability indicated that the (TSC-CC) resin had a good stability and can be recycled as a promising agent for removal of Ag+.Keywords:chelating resin;silver ions;selectivity;adsorption;mechanism
研究领域:
化学工程
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环境科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CELLULOSE
·
2021
·Vol. 29
·期 2
·941-952
·
IF 5.044
Hu Tao,Hu Xiaoli,Tang Cheng,Liu Dan
This paper describes the synthesis of a novel chelating material derived from cellulose, and its heavy metal ion adsorption properties from aqueous solution. The first section of this paper reports the chemical grafting of cellulose, that amino acetic acid groups were grafted onto the cellulose by in situ synthesis, a novel yet unreported modified cellulose derivative N,N-(dicarboxymethylaminoethyl, carboxymethyl)aminoethylamine carboxymethyl cellulose amide was synthesized. This obtained adsorbent was characterized by elemental analysis, infrared spectroscopy (IR) and Solid State Nuclear Magnetic Resonance (SSNMR) 13 C NMR spectroscopy. In the second section, the adsorption of Cu 2+ and Pb 2+ from single metal ion aqueous solutions onto this adsorbent were evaluated and analyzed by the Freundlich and Langmuir models. Further more, adsorption capacity for Ba 2+ , Mg 2+ , Mn 2+ , Co 2+ , Zn 2+ , Pb 2+ , Ni 2+ and Cu 2+ , and the competitive adsorption of this adsorbent between ions were also evaluated by ICP spectroscopy. The results indicated that this modified cellulose exhibited adsorption properties similar to those of EDTA, and showed good adsorption capacity for a wide range of metal ions.
Graphical abstract
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF CHROMATOGRAPHY A
·
2015
·
IF 4.169
Hu Liu,Xiaoyan Dong,Yan Sun
A series of highly charged nanoscale chelators were fabricated by grafting of poly(glycidyl methacrylate-iminodiacetic acid) (pGI) chains with iminodiacetic acid (IDA) chelating group on silica nanoparticles (SNPs) via atom transfer radical polymerization (ATRP). The nanoscale chelators, denoted as SNPs-pGI, possessed a nickel ion chelating capacity as high as 2800 μmol/g, 50 times higher than the IDA-modified Sepharose FF (IDA-Sepharose) resin reported in literature and offered a high affinity binding capacity for hexahistidine-tagged enhanced green fluorescence protein (6 × His-EGFP) after nickel ion loading. More importantly, the anionic SNPs-pGI of high charge densities displayed much better performance than IDA-Sepharose in facilitating the refolding of like-charged 6 × His-EGFP from inclusion bodies (IBs). For example, for 0.2 mg/mL 6 × His-EGFP IB refolding, addition of 6.2 μL/mL SNPs-pGI with the highest charge density led to a refolding yield of 90%, over 43% higher than that obtained with 460 μL/mL IDA-Sepharose. It is notable that the much higher efficiency of the nanoscale chelator was obtained with a chelator consumption corresponding to only 1.4% of IDA-Sepharose. Moreover, the highly charged SNPs-pGI could efficiently facilitate the refolding of 6 × His-EGFP at higher IB concentrations (0.4 and 0.8 mg/mL). After refolding, nickel ions addition led to the recovery of the refolded 6 × His-EGFP with high yield (80%), purity (96%) and enrichment ratio (1.8). All the results suggest that the SNPs-pGI of high charge densities were promising for cost-effective recovery of His-tagged proteins expressed as IBs with the integrative like-charge facilitated refolding and metal-chelate affinity purification strategy.
研究领域:
生物化学
·
纳米技术
·
蛋白质工程
✓ 已验证
DOI
PubMed
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2018
·
IF 5.091
Xiaoli Huang,Di Lu,Yongmin Ma,Limei Zhang,Lina Wang,Jian Deng,Zheng Wang,Yanjun Zhao
We report a self-assembly-based approach for improved iron chelation of small chelators. A model chelator, deferiprone (DFP) is covalently linked to amphiphilic poly(ethylene glycol)-polypeptide block copolymer that can assemble into micelles . The free DFP generally coordinates with iron in a ratiometric manner (3:1). However, the assembly induces DFP packing in the micelle cores, which restricts its conformational freedom. Hence DFP/iron coordination ratio in micelles is reduced (< 3:1), which leads to an enhanced chelation performance of DFP. In addition, the micellar nanocarrier usually exhibits an extended systemic circulation in contrast to the free DFP. The current work opens new avenues for developing novel nanomedicines for iron overload diseases.
研究领域:
生物化学
·
药学
✓ 已验证
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）