CARBOHYDRATE POLYMERS
·
2022
·
IF 10.723
Congwei Li,Lian Duan,Xinjian Cheng
Fluorescent chitosan-based hydrogel for the selective detection and adsorption of Hg 2+ /Hg + in aqueous environment was prepared through three-step synthesis strategy. NO 2 -Boron-dipyrrolemethene (BODIPY) was prepared firstly, and then the -NO 2 group was reduced to -NH 2 group. Finally, the NH 2 -BODIPY was introduced to chitosan by Schiff base formation reaction through bi-aldehyde. Eventually, fluorescent chitosan hydrogel was obtained. The as-prepared fluorescent hydrogel probe could detect Hg 2+ /Hg + through PET mechanism with the detection limit of 0.3 μM. The recognition site which combines Hg 2+ /Hg + is C N, it is just formed in the reaction with chitosan and the amino group on BODIPY. Adsorption capacity of the fluorescent hydrogel is 121 mg·g −1 , which is almost seven times of the original chitosan. The isotherm and kinetics of Hg 2+ /Hg + removal follows Langmuir isotherm and pseudo-second order kinetics , respectively. Besides, a series of fluorescent hydrogels were prepared to compare the elasticity, hydropHilicity , fluorescence intensity and adsorption capacity.
研究领域:
材料科学
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环境科学
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化学工程
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DOI
PubMed
高影响因子
Frontiers in Chemistry
·
2021
·
IF 5.221
Geng Xue,Qu Rongjun,Kong Xiangyu,Geng Shengnan,Zhang Ying,Sun Changmei,Ji Chunnuan
Dendrimers as commonly used metal ions adsorption materials have the advantages of good adsorption performance and high reuse rate, but the high cost limits its extensive use. Compared with dendrimers, hyperbranched dendrimers have similar physical and chemical properties and are more economical. Therefore, hyperbranched dendrimers are more suitable for industrial large-scale adsorption. The hyperbranched polyamidoamine (HPAMAM) gels were prepared by cross-linking hyperbranched polyamidoamine (HPAMAM-ECH-x and HPAMAM-EGDE-x) with different amounts of epichlorohydrin (ECH) and ethylene glycol diglycidyl ether (EGDE), respectively. The as-synthesized adsorbents were characterized by FT-IR, SEM and XPS. The prepared adsorbents were used to adsorb Hg(Ⅱ) in aqueous solution, and the effects of solution pH, contact time, temperature and initial concentration of metal ion on the adsorption capacity were investigated. The effect of solution pH indicated that the optimum condition to Hg(Ⅱ) removing was at pH 5.0. The adsorption kinetic curves of the two kinds of materials were in accordance with the pseudo-second-order model. For the HPAMAM-ECH samples, the adsorption thermodynamic curves fitted the Langmuir model, while for the HPAMAM-EGDE samples, both Langmuir and Freundlich equations fitted well. The maximum adsorption capacity of HPAMAM-ECH-3 obtained from Langmuir model toward Hg(Ⅱ) was 3.36 mmol/g at pH 5.0 and 35°C.
研究领域:
材料科学
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环境科学
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DOI
PubMed
高影响因子
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
·
2022
·Vol. 30
·期 1
·2283-2297
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IF 5.19
Hu Yuting,Wang Shixing,Zhang Libo,Yang Fan
In wastewater, heavy metal Hg causes serious harm to ecology, so it needs to be removed. In this paper, a novel MOF adsorbent (UiO-66-QU) was prepared by modifying UiO-66-NH 2 with 4-quinolinecarboxaldehyde, which was used to selectively remove Hg(II) from water. The adsorbent was characterized using Fourier transform infrared spectroscopy (FT-IR), field emission scanning electron microscopy (SEM), Brunauer–Emmett–Teller (BET), zeta potentiometer, and X-ray photoelectron spectroscopy (XPS). In order to investigate the Hg(II) adsorption performance of UiO-66-QU, the effect of time, initial concentration, pH, and temperature were carried out. Langmuir model fitting shows that the maximum adsorption capacity of UiO-66-QU for Hg(II) is 556 mg/g at 298 K. The experimental results show that UiO-66-QU has better Hg(II) adsorption capacity than UiO-66-NH 2 . The isotherm is in accordance with pseudo-second-order models. It is indicated that the adsorption process is mainly monolayer chemical adsorption. The thermodynamic parameters also indicate that the adsorption process is spontaneous and endothermic. It has excellent reusability and selectivity. XPS and the zeta potential showed that the adsorption mechanism was the complex reaction of Hg(II) with nitrogenous group. Therefore, the adsorbent has potential application prospects in removal of Hg(II) from wastewater.
研究领域:
环境科学
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材料科学
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DOI
PubMed
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
·
2022
·
IF 9.221
Kaiqi Liu,Luminita Marin,Xinjian Cheng
In this work, fluorescent β- cyclodextrin (β-CD) based probes containing naphthalimide group were synthesized to realize the specific recognition of Hg 2+ /Hg + in aqueous system. Firstly, three small fluorescent molecules (N1, N2 and N3) with -NH 2 groups were synthesized from 4-bromo-1, 8-naphthalene anhydride . Secondly, CH CCH 2 - group was introduced into β-CD by Williamson ether formation reaction. Finally, the target probes (β-CD-PI, β-CD-PY and β-CD-TP) were obtained by Amino-Yne click reaction. These probes can efficiently recognize Hg 2+ /Hg + . β-CD-PI emits bright yellow fluorescence after binding with Hg 2+ /Hg + , which is a turn-on fluorescent probe . When the Hg 2+ /Hg + concentration exceeds 26 μM, the fluorescence intensity amplifies sharply (20 folds). The hydrophobic parts of the probes aggregated together to form a micelle-like structure due to complexation with Hg 2+ /Hg + , resulting in special micelle-sensitizing properties. Meanwhile, the HOMO-LUMO energy levels of the probes were calculated by cyclic voltammetry (CV). The probe is expected to be used for the detection of Hg 2+ /Hg + in aqueous solutions without any organic solvents.
研究领域:
分析化学
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环境科学
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材料科学
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DOI
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
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2023
·
IF 8.2
Xin Yan,Huacai Ge
In this study, a novel modified chitosan composite adsorbent (UNCS) was prepared by crosslinking between chitosan and metal organic frameworks (MOFs) material UiO-66-NH 2 using epichlorohydrin as crosslinker. The influence of the prepared conditions was investigated. The structure and morphology of the composite were characterized by FT-IR, XRD, SEM, TGA, BET and zeta potential analysis. Effects of different variables for adsorption of Hg(II) on this adsorbent were explored. The kinetic studies indicated that the adsorption process followed the pseudo-second-order kinetic model and the adsorption equilibrium could be reached within 2 h. The adsorption was mainly controlled by chemical process. Adsorption isothermal studies illustrated that the adsorption fitted Langmuir isotherm model, implying the homogeneous adsorption on the surface of the adsorbent. The adsorbent exhibited high uptake and the maximum capacity from Langmuir model could reach 896.8 mg g −1 at pH 6. Thermodynamic studies showed the spontaneous nature and exothermic nature of the adsorption process. Additionally, the removal of Hg(II) on UNCS could achieve over 90 %. The adsorption-desorption cycled experiments indicated the appropriate reusability of the adsorbent. Hence, this adsorbent would be promising for the removal of Hg(II) from wastewater.
研究领域:
环境科学
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材料科学
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PubMed
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2024
·
IF 7.7
Boyun Wang,Wanqi Zhang,Yuan Zhong,Yuan Guo,Ximing Wang,Xiaotao Zhang
Ions of mercury, one of the most hazardous heavy metals in nature, pose serious risks to the environment and human health. Blue sulfur-doped carbon dots (SCDs) from corn stalks were utilized as material. The SCDs were incorporated into a carboxylated hydrogel modified with sulfur, and a compound gel (SCDs–KTOCS gel) was successfully fabricated for simultaneous fluorescence detection and Hg(II) adsorption. This enabled the effective identification and removal of Hg(II) from contaminated water. The chemical content, fluorescence properties, and adsorption behaviors of the SCDs–KTOCS–gels were analyzed. The results demonstrate that the SCDs–KTOCS–gels exhibited effective Hg(II) adsorption (193 mg/g) and an extensive linear spectrum for Hg(II) fluorescence emission (150–500 mg/L; detection limit = 1.5668 mg/L). The adsorption values fit well with the Temkin models and pseudo-second-order kinetics. Additionally, Hg(II) detection and adsorption in the SCDs–KTOCS–gels were examined. By exchanging the existing probe for a suitable one that fits various relevant applications, this study suggests an environmentally friendly and sustainable method of producing materials for removing and detecting Hg(II) and constructing a fluorescence hydrogel for the detection and adsorption of different metals.
研究领域:
环境科学
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材料科学
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化学
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可持续技术
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PubMed
高影响因子
COLLOID AND POLYMER SCIENCE
·
2014
·Vol. 292
·期 9
·2157-2172
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IF 2.41
Chen Xing Juan,Cai Jian Chong,Zhang Zheng Han,Liu Li Jia,Yang Guang Lei
A novel cross-linked chitosan-poly(aspartic acid) chelating resin was synthesized by combining chitosan and poly(aspartic acid) derivative with crosslinker. The structure and morphology of the resin containing disulfide bonds were characterized by 1 H NMR, FT-IR, Raman spectra, and SEM. Adsorption of Pb(II) and Hg(II) from aqueous solution by the resulted chelating resin was investigated in batch techniques. The result of the Raman spectra suggests that the disulfide bonds in the resin also play an important role in the adsorption of Pb(II) and Hg(II). The kinetic data were fitted to pseudo-first-order, pseudo-second-order, and intraparticle diffusion models, which is suggestive of following closely the pseudo-second-order kinetic model. Equilibrium data were fitted to Langmuir, Freundlich, and D–R isotherm models. The results of equilibrium isotherm reveal that the empirical Langmuir equation provides an accurate description of the experimental data under the studied concentration range. In addition, thermodynamic and regeneration properties of the adsorbent were also studied.
研究领域:
环境科学
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材料科学
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DOI
高影响因子
ELECTROCHIMICA ACTA
·
2021
·
IF 6.901
Jinrui Li,Zhongxin Zhuang,Zheng Guo,Zhonggang Liu,Xingjiu Huang
Exploiting advanced bimetallic oxide as sensing materials for electroanalysis offers new opportunity to improve the electrochemical performance, but still presents a tough challenge. Herein, we synthesized the uniform Fe 2 O 3 /Mn 3 O 4 nanocubes from a framework structure in a facile approach, which were developed as the electrochemical catalyst for individual and simultaneous analysis of Cu(II) and Hg(II) in 0.1 M HAc-NaAc buffer solution (pH5.0). It showed the excellent electrochemical behavior for the simultaneous analysis Cu(II) and Hg(II) with high sensitivities of 69.29 and 190.55 μA μM cm −2 . The corresponding limit of detection values (LODs) were calculated to be 3.94 nM and 1.39 nM, respectively. The excellent electrochemical behavior of Fe 2 O 3 /Mn 3 O 4 could be attributed to the large specific surface area, which could provide a large number of adsorption sites for Cu(II) and Hg(II). Meanwhile, the bimetallic Fe and Mn atoms arranged in the porous nanocubes could offer a synergistic effect and improve the electrochemical activity. Moreover, it could be successfully applied for the simultaneous analysis of Cu(II) and Hg(II) in real water samples with the favorable recovery rate. The results confirmed that the Fe 2 O 3 /Mn 3 O 4 nanocubes could serve as a reliable platform for the simultaneous analysis of Cu(II) and Hg(II).
研究领域:
分析化学
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材料科学
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DOI
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2023
·
IF 8.2
Jiao He,Lin Yun,Xinjian Cheng
Chitosan as the plentiful and easily available natural polymer, its solubility in organic solvents is still a challenge. In this article, three different chitosan-based fluorescent co-polymers were prepared by reversible addition-fragmentation chain transfer (RAFT) polymerization. They could not only dissolve in several organic solvents, but also could selectively recognize Hg 2+ /Hg + ions. Firstly, allyl boron-dipyrrolemethene (bodipy) was prepared, and used as one of the monomers in the subsequent RAFT polymerization. Secondly, chitosan-based chain transfer agent (CS-RAFT) was synthesized through classical reactions for dithioester preparation. Finally, three methacrylic ester monomers and bodipy bearing monomers were polymerized and grafted as branched-chains onto chitosan respectively. By RAFT polymerization, three chitosan-based macromolecular fluorescent probes were prepared. These probes could be readily dissolved in DMF, THF, DCM , and acetone. All of them exhibited the ‘turn-on’ fluorescence with selective and sensitive detection for Hg 2+ /Hg + . Among them, chitosan-g-polyhexyl methacrylate-bodipy (CS-g-PHMA-BDP) had the best performance, its fluorescence intensity could be increased to 2.7 folds. In addition, CS-g-PHMA-BDP could be processed into films and coatings. When loading on the filter paper, fluorescent test paper was prepared and it could realize the portable detection of Hg 2+ /Hg + ions. These organic-soluble chitosan-based fluorescent probes could enlarge the applications of chitosan.
研究领域:
材料科学
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分析化学
·
生物医学工程
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PubMed
高影响因子
ACS Applied Nano Materials
·
2023
·
IF 5.9
Lulu Kong,DeZhu Chen,Xiaolong Zhang,Lin Zhou,Yongming Deng,Shaohua Wei
The growth of oxides on the surface of noble metals and the introduction of alloys are effective methods to enhance the catalytic activity of noble metals. However, the fabrication of noble metal oxides always involves harsh experimental conditions and the oxidation degree could not be controlled. Herein, a simple, fast, and controlled Pd oxidation method by mixing Hg2+ and Pd nanosheets (PdNSs) under mild conditions to form PdxHgy(PdO)z (PHOs) was reported, which consists of the Pd–Hg alloy and PdO. The density functional theory (DFT) calculation and experiment results proved that the Hg atom incorporation promotes the nearby Pd–Pd bond breaking, initiating a cascade of PdO generation. More precisely, 1 Hg atom incorporation induced ∼8 Pd atom oxidation, ensuring that the oxidation degree of Pd could be easily controlled by adjusting the ratio of Hg2+ and PdNS. As a peroxidase-mimicking nanozyme, the PHO affinity for its substrate could be 21.7- and 123.6-fold greater than that of the PdNS and the natural peroxidase (HRP), respectively. For the colorimetric immunoassay of carcinoembryonic antigen (CEA) detection, PHO has an ultralow detection limit of 1.33 pg mL–1, which is ∼8.6 and ∼282 times lower than that of the PdNS and the natural HRP, respectively.
研究领域:
生物化学
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医学诊断
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材料科学
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DOI
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
·
2016
·
IF 4.758
Linghao He,Shuai Zhang,Minghua Wang,Donglai Peng,Fufeng Yan,Zhihong Zhang,Liming Zhou
Two novel nanocomposites of zinc phosphate [Zn 3 (PO 4 ) 2 ] and Hg 2+ -targeted DNA [Zn 3 (PO 4 ) 2 @DNA] and Zn 3 (PO 4 ) 2 and multi-wall carbon nanotubes (MWCNTs) modified with Hg 2+ -targeted DNA [Zn 3 (PO 4 ) 2 @MWCNTs-DNA] were fabricated by the assembly of Hg 2+ -targeted DNA strands with Zn 2+ ions. Two as-prepared nanocomposites were subsequently used as electrochemical biosensors for sensitively detecting Hg 2+ due to the combination effect of the formation of T–Hg 2+ –T coordination between DNA strands and Hg 2+ and the direct adsorption of Hg 2+ onto porous nanocomposites. In comparing with Zn 3 (PO 4 ) 2 @DNA nanocomposite, the crystallization degree of Zn 3 (PO 4 ) 2 @MWCNTs-DNA was improved due to the presence of MWCNTs, which further enhance electrochemical activity of the nanocomposite. As a result, Zn 3 (PO 4 ) 2 @MWCNTs-DNA nanocomposite-based electrochemical biosensor showed a higher sensitivity toward Hg 2+ detection in aqueous solution than Zn 3 (PO 4 ) 2 @DNA-based biosensor. It showed a detection limit of 0.071 nM within the range of 0.1–50 nM of the concentration of Hg 2+ . This newly developed biosensor also presented excellent selectivity, repeatability, and applicability in Hg 2+ detection. Therefore, the fabricated Zn 3 (PO 4 ) 2 -based nanocomposite using this novel strategy showed their considerable potential use in water or environmental treatment.
研究领域:
环境科学
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分析化学
·
生物传感技术
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DOI
高影响因子
ANALYST
·
2020
·Vol. 145
·期 6
·2191-2196
·
IF 3.978
Fen-Ying Kong,Lei Yao,Xin-Yang Lu,Heng-Ye Li,Zhong-Xia Wang,Hai-Lin Fang,Wei Wang
The Au–Hg amalgam anchored on the surface of reduced graphene oxide nanosheets (Au–Hg/rGO) has been synthesized successfully and characterized by various techniques such as transmission electron microscopy, X-ray diffraction and X-ray photoelectron spectroscopy. The Au–Hg/rGO nanocomposites were found to possess excellent peroxidase-like catalytic activity and can quickly catalyze the oxidation of colorless 3,3′,5,5′-tetramethylbenzidine (TMB) to blue oxTMB in the presence of H2O2. The obvious color change offered accurate determination of the H2O2 concentration by recording the absorbance at 652 nm using a UV-vis spectrophotometer. The linear response range for H2O2 was from 5 μM to 100 μM and the detection limit was 3.25 μM (S/N = 3). Furthermore, a kinetic study indicated that the catalytic behavior of Au–Hg/rGO nanocomposites followed the typical Michaelis–Menten theory and Au–Hg/rGO nanocomposites showed good affinity for H2O2. We envision that the simple and sensitive colorimetric detection system holds great promising applications in clinical diagnostics and food and environment monitoring.
研究领域:
生物化学
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分析化学
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材料科学
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DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）