LANGMUIR
·
2018
·
IF 3.789
Jianfeng Zhang,Qunling Fang,Jinyu Duan,Hongmei Xu,Huajian Xu,Shouhu Xuan
This work reports a novel Fe3O4@polydopamine/Au/polydopamine core/shell nanocomposite toward a magnetically separable nanocatalyst. Because the polydopamine (PDA) layer-sandwiched Au nanocrystals were prepared by a layer-by-layer method, the content of Au could be controlled by varying the Au shell number (such as burger-like Fe3O4@PDA/Au/PDA/Au/PDA). Fe3O4@PDA/Au/PDA exhibited excellent catalytic activity in reducing p-nitrophenol because the substrate could penetrate the PDA shell. Owing to the protection of the PDA shell, Fe3O4@PDA/Au/PDA presented higher cyclability than Fe3O4@PDA/Au. The activity of Fe3O4@PDA/Au/PDA maintained 95% after 7 cycles, while that of Fe3O4@PDA/Au was only 61%. The detailed cycling catalytic mechanism was investigated, and it was found that the catalytic rate of Fe3O4@PDA/Au/PDA/Au/PDA was faster than that of Fe3O4@PDA/Au/PDA because of the higher Au content. Interestingly, this method could be extended for other magnetic nanocomposites with two different kinds of noble metal nanocrystals integrated within one particle, such as Fe3O4@PDA/Au/PDA/Ag/PDA and Fe3O4@PDA/Au/PDA/Pd/PDA.
研究领域:
材料科学
·
化学工程
·
纳米技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
COMPOSITES PART B-ENGINEERING
·
2022
·
IF 11.322
Xiaohuan Liu,Wenwu Cheng,Yangmi Yu,Shengtao Jiang,Yuzhi Xu,Enmin Zong
A novel adsorbent of ZrO 2 /PEI/Fe 3 O 4 functionalized MWCNTs composite (MWCNTs@Fe 3 O 4 @PEI-Zr) possessing a high affinity to phosphate and easily separated from aqueous solution was proposed in this work. The ZrO 2 and PEI modified on the surface act as active sites for the removal of phosphate, while the Fe 3 O 4 allows for the easy separation by applying an external magnetic field . Compared to traditional separation like centrifugation, magnetic separation markedly reduces energy consumption and provides more possibilities for application. The composite exhibits a relatively high surface area of 162.9 m 2 g -1 with a larger number of mesopores. As-prepared MWCNTs@Fe 3 O 4 @PEI-Zr is found to have a relatively high phosphate adsorption capacity of 21.14 mg P g −1 and it can be recovered rapidly from water under an external magnetic field . Moreover, MWCNTs@Fe 3 O 4 @PEI-Zr exhibits an outstanding anti-interference capability in terms of the coexisting ion and ionic strength of solutions. Importantly, the dissolution of Zr and Fe are negligible (less than 0.015 mg L −1 ) over a wide pH range of 4.04–9.98, indicating that the MWCNTs@Fe 3 O 4 @PEI-Zr is a structurally stable hybrid composite particle with strong interaction. Furthermore, it shows a good reusability and 86.2% removal efficiency of phosphate remains after three consecutive cycles. Both the ligand exchange and the electrostatic attraction are mainly responsible for phosphate removal by MWCNTs@Fe 3 O 4 @PEI-Zr. This work demonstrated that the highly efficient, easy separable, high stability and reusability MWCNTs@Fe 3 O 4 @PEI-Zr composite has the potential for phosphate removal.
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
WASTE MANAGEMENT
·
2023
·
IF 8.1
Cong Li,Xiaofeng Yang,Yongkui Li,Yu Chen,Xiaodong Pan,Yongping Xie,Xingyu Liu,Suqin Li
Hematite tailings (HTs) are rich in silica and are used as replacements for fine aggregates in the preparation of construction materials. However, there is scope for a more effective utilization of the valuable elements present in HTs. In this paper, a process for preparing high-purity SiO 2 using HTs procured from Ansteel (China) is proposed. HTs were treated using the superconducting high-gradient magnetic separation (S-HGMS) technology, where the silica as part of the nonmagnetic fraction was obtained in the form of a high-silica concentrate, which was then subjected to mixed-acid leaching to dissolve impurities to achieve refined purification. The optimum process conditions for S-HGMS were determined, and the response surface methodology was applied to optimize the process parameters of the mixed-acid leaching process. The process indicators of the mixed-acid leaching step included the leaching time, leaching temperature, and molar ratio of the mixed acids. The optimum process conditions for S-HGMS were as follows: the magnetic strength-to-velocity ratio in the weak magnetic separation stage was set to 0.034 T·s/m whereas it was maintained at 0.076 T·s/m in the strong magnetic separation stage; the pulp concentration was 40 g/L, the pulp velocity was 500 mL/min, and the dispersant concentration was 1 mg/g. Under these conditions, the high-silica pulp was processed. The corresponding SiO 2 grade increased from 71.788 % to 95.260 %, and its recovery and yield reached 56.330 % and 42.450 %, respectively. The SiO 2 content in the sample increased from 95.260 % to 99.961 %. Further, the mechanisms of the S-HGMS and mixed-acid leaching were revealed. The proposed process is environmentally friendly and operationally inexpensive. It can reduce the amount of HTs by 42.450 %, and the obtained high-purity silica product has high economic value and good industrialization prospects.
研究领域:
材料科学
·
环境工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
MICROCHIMICA ACTA
·
2024
·Vol. 191
·期 8
·1-11
·
IF 5.3
Wang Chunxin,Deng Rong,Li Haiqin,Liu Zhigang,Niu Xiaofeng,Li Xiaochun
An intelligent colorimetric sensing platform integrated with in situ immunomagnetic separation function was developed for ultrasensitive detection of Escherichia coli O157: H7 ( E. coli O157: H7) in food. Captured antibody modified magnetic nanoparticles (cMNPs) and detection antibody/horseradish peroxidase (HRP) co-functionalized AuNPs (dHAuNPs) were firstly synthesized for targeted enrichment and colorimetric assay of E. coli O157: H7, in which remarkable signal amplification was realized by loading large amounts of HRP on the surface of AuNPs. Coupling with the optical collimation attachments and embedded magnetic separation module, a highly integrated optical device was constructed, by which in situ magnetic separation and high-quality imaging of 96-well microplates containing E. coli O157: H7 was achieved with a smartphone. The concentration of E. coli O157: H7 could be achieved in one-step by performing digital image colorimetric analysis of the obtained image with a custom-designed app. This biosensor possesses high sensitivity (1.63 CFU/mL), short detecting time (3 h), and good anti-interference performance even in real-sample testing. Overall, the developed method is expected to be a novel field detection platform for foodborne pathogens in water and food as well as for the diagnosis of infections due to its portability, ease of operation, and high feasibility. Graphical Abstract
研究领域:
生物技术
·
分析化学
·
食品科学
·
微生物学
·
传感器与执行器
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF MATERIALS CHEMISTRY
·
2011
·Vol. 21
·期 43
·17353-17359
·
IF 5.101
Xi-Lin Wu,Lei Wang,Chang-Lun Chen,An-Wu Xu,Xiang-Ke Wang
A composite material, containing magnetite particles, graphene and layered double hydroxides (LDHs) was fabricated through a simple two-step reaction. Graphene was used as the matrix for supporting magnetite particles and LDH nanoplates. The synthesized magnetite-graphene-LDH (MGL) composites were characterized by field emission scanning electron microscopic (FE-SEM), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HR-TEM), energy-dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD), thermogravimetric analysis (TGA), Fourier transformed infrared (FTIR) spectroscopy, N2adsorption-desorption, and X-ray photoelectron spectroscopy (XPS). The MGL composites were applied to remove arsenate from aqueous solutions and could be easily separated by magnetic separation process. The results showed enhanced adsorption capacity of arsenate on the MGL as compared to that of pure Mg/Al LDHs. The surface area of MGL is greatly enhanced through the incorporation of magnetite particles and graphene, which provides more active sites for arsenate uptake. Moreover, LDHs were hybridized with mechanically and chemically stable graphene materials, providing an accessible diffusion pathway in the macropore domain, and therefore their adsorption capacity was enhanced. The fast and efficient adsorption of arsenate from solution to MGL suggests that the MGL composites are potential and suitable materials in the preconcentration of arsenate from large volumes of aqueous solutions in wastewater treatment.
研究领域:
环境科学
·
材料科学
✓ 已验证
DOI
高影响因子
BIOSENSORS & BIOELECTRONICS
·
2017
·
IF 7.78
Shuzhen Yue,Tingting Zhao,Sai Bi,Zhipeng Zhang
High throughput analysis of miRNAs is of great significance to clinical and biomedical applications . In this work, we have developed a highly sensitive and selective chemiluminescence imaging array (CLIA) for simultaneous detection of three miRNAs with high throughput, easy operation and low cost. In this assay, three kinds of hairpins that can specially recognize respective miRNAs (miR-155, miR-let-7a and miR-141) are parallel modified on the magnetic beads (MBs). The employment of MBs enables quick sorting of multiplex targets in high yield and purity with high throughput. Upon introduction of the target miRNAs, they hybridize to the corresponding hairpins and initiate the DNA machines with the assistance of Klenow fragment exo- DNA polymerase and Nb.BbvCI NEase , achieving exponential amplification of targets. After that, the toehold-mediated strand displacement (TMSD) reactions are performed through sequential addition of displacement probes under magnetic separation, resulting in the release of HRP-tagged DNA hybrids in solution for CL imaging and recovery of MBs for repetitive use. This CLIA method demonstrates ultrahigh sensitivity with detection limits down to fM level, wide linear range over 5 orders of magnitude, excellent selectivity to distinguish one-base mismatched target miRNA, and good performance in real sample analysis. Together with the advantages of high throughput, easy operation, acceptable accuracy, and good recyclability and reproducibility, the proposed multiplex CLIA method holds great potential in practical applications, such as profiling the pattern of miRNA expression, disease screening, biomedical research, and so on.
研究领域:
生物医学工程
·
分子诊断学
✓ 已验证
DOI
PubMed
高影响因子
MINERALS ENGINEERING
·
2019
·
IF 3.315
Suhong Zhang,Yanlong Wen,Liguang Wang,Yongkang Yang,Shengyu Liu
A multifunctional polymer that was magnetic and had a high water absorption ability was prepared via synthesis of magnetite nanoparticles followed by surface modification and polymerization. The structure and morphology of the multifunctional polymer were characterized by X-ray diffractometer (XRD), Fourier transform infrared (FTIR), scanning electron microscope (SEM), transmission electron microscope (TEM), and energy dispersive X-ray spectroscope (EDS). The magnetite content and the magnetic property of the multifunctional polymer were analyzed by thermogravimetric analysis (TGA) and superconducting quantum interference device magnetometer (SQUID), respectively. The results suggested that the multifunctional polymer had a stable core-shell structure, a striking temperature-responsive property, and stable magnetic property. Further work was carried out to assess the performance of this multifunctional polymer at a particle size of 0.3–0.45 mm for dewatering of fine coal (<0.25 mm in size). It was found that the multifunctional polymer could give fast kinetics of dewatering and after each cycle, the polymer could be readily separated by simple magnetic separation and then regenerated and reused in next cycle while maintaining the same dewatering performance.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2019
·
IF 3.45
Haifen Xu,Zichen Xu,Jin Zhou,Ge Yan,Xiaowei Li,Shuping Zhuo
Novel magnetically separable BiOBr/magnetic reduced graphene oxide (BiOBr/MRGO) composite photocatalysts were fabricated using a one-step hydrothermal treatment . The photodegradation of RhB was choose as model reaction to evaluate the photocatalytic performance of as-prepared BiOBr/MRGO composites under visible light. The research results indicated that photocatalytic activities of all BiOBr/MRGO composites were markedly improved, compared to the single BiOBr. Among them, the BiOBr/MRGO hybrids with a MRGO mass ratio of 10% presented the highest photodegradation ability, and the kinetic constant of degradation was about 2 times higher than that of BiOBr. The enhancement of catalytic property was assigned to the increase of visible light absorption and the hindrance of photogenerated electron-hole pairs recombination originating from the introduction of MRGO. More importantly, BiOBr/MRGO exhibited excellent cycling stability after four cycles and could be easily separated by an external magnet and reused, which was convenient to the purification of organic pollutants.
研究领域:
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2014
·
IF 2.235
Jun Chen,Weijie Wen,Linjun Kong,Shuanghong Tian,Fuchuan Ding,Ya Xiong
Magnetically separable MnFe2O4 was prepared successfully by a sol–gel combustion method. The synthesized MnFe2O4 was characterized by X-ray diffraction (XRD), scanning electronic microscopy (SEM), Brunauer–Emmett–Teller (BET) surface area, zeta potential, and magnetic hysteresis loops. The catalytic activity of MnFe2O4 was evaluated by the ozonation of 4-chlorophenol (4-CP) at different solution pH value, ozone gas concentration, MnFe2O4 dosage, and initial 4-CP concentration. The ozone consumption was monitored and the ·OH exposure was calculated in different processes. It was found that MnFe2O4 was highly effective in catalyzing ozone decomposition and favored to generate more hydroxyl radicals. Moreover, the synergistically catalytic effect between Mn and Fe in MnFe2O4 was confirmed. Finally, lifetime of MnFe2O4 was measured in a novel integrated membrane-heterogeneous catalytic ozonation reactor designed for the first time. All the experimental results show that MnFe2O4 is a highly recoverable, efficient, and durable catalyst in the ozonation.
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
SENSORS AND ACTUATORS B-CHEMICAL
·
2021
·
IF 7.46
Liyan Zhang,Xiaoting Liu,Nan Zhang,Xianqiang Liu,Wei Jiang
Sensitive and accurate detection of flap endonuclease 1 (FEN1) is essential to understand its roles in DNA replication and repair and explore its functions in tumor diagnosis and prognosis. Here, we designed a magnetic separation-assisted cascade hybridization chain reaction (HCR) amplification strategy for enzyme-free and sensitive detection of FEN1. Firstly, the forked dsDNAs contained the recognition site (5′ overhanging DNA flap) of FEN1 were modified on magbeads surface to form magnetic recognition probes. By the recognition and catalytic cleavage of FEN1, the 5′ flaps were removed into solution and then purified by magnetic separation. Then, the obtained flaps served as triggers to activate the linear-assembly of hairpin probes H1 and H2 (primary HCR), forming nicked double helices with split fragments. Finally, the fragments acted as new triggers to activate the branched-assembly of hairpin probes H3 and H4 (secondary HCR), causing fluorophore/quencher labeled on H3 far away and fluorescence recovery. Benefiting from the purification of triggers by magnetic separation and the signal amplification effect of cascade HCR, this strategy achieved a low detection limit of 3.6 × 10 −5 U μL −1 for FEN1, and enabled the assay of it in actual samples. The results demonstrate that our strategy will provide a potent approach for sensitive detection of FEN1 in early tumor diagnosis and prognosis.
研究领域:
分子生物学
·
肿瘤诊断
·
生物化学
✓ 已验证
产品关联
DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2025
·
IF 5.4
Liyang Zhou,Aixue Bi,Xu Yang,Feng Xue,Shengui Ju
Titanium-based lithium-ion sieves (LISs) have attracted considerable attention because of their superior adsorption capacity and cycling stability in lithium ion extraction. In this paper, an S-doped H 2 TiO 3 -ferrite ion sieve was successfully synthesized through co-precipitation scheme. The recycling problem of lithium ion sieve powder was effectively solved by utilizing its magnetic separation property. LTSO-Ferrite was prepared in one step using a high-temperature solid-phase method, with an optimal molar ratio of FeCl 2 : TiS 2 : TiO 2 = 0.2: 0.2: 1. The adsorption capacity of S-doped H 2 TiO 3 -Ferrite (HTSO-Ferrite) reached 43.02 mg/g, and the magnetization value was 4.81 emu/g. The adsorption energy and structure of Li + on LTSO-Ferrite were determined using density functional theory (DFT) to assess the feasibility of lithium absorption. The adsorption behavior of LTSO-Ferrite toward Li + followed the Langmuir isotherm and pseudo-second-order kinetic models, indicating that the adsorption was endothermic and spontaneous. LTSO-Ferrite exhibited good selectivity for heteroatoms in simulated brine. Magnetic recovery rate remained at 98 % with an adsorption capacity of 36.16 mg/g after five cycles, which is 84 % of its maximum adsorption capacity. LTSO-Ferrite exhibited magnetic separation properties, offering a promising approach for developing lithium adsorbents for extraction from unsalted lake brine.
研究领域:
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
LAB ON A CHIP
·
2025
·
IF 5.4
Yu-Xin Zhang,Ming Wang,Li-Li Xu,Yijing Chen,Shu-Ting Zhong,Ying Feng,Hai-Bo Zhang,Shi-Bo Cheng,Min Xie,Wei-Hua Huang
Exosomes have gained increasing attention as robust, biocompatible carriers for targeted therapy. However, current techniques for exosome drug loading suffer from low drug loading efficiency, substantial exosome loss during repeated purification and quantification processes. Here, we present an integrated microfluidic chip (IMC) that streamlines drug loading, separation, and electrochemical detection of exosomes from plasma in a single device. In this design, the three-dimensional (3D) macroporous scaffold and the magnetoresponsive electrode are successfully assembled into the modeling microchip, playing the functions of “3D chaotic flow mixer”, “magnetic separator” and “electrochemical detector”. When plasma, doxorubicin (DOX), boron clusters and immunomagnetic nanoprobes (IMP) are simultaneously injected into the IMC, the exosomes are loaded with DOX-boron cluster (EDB) complexes and synchronously recognized by IMP in the “3D chaotic flow mixer”. Our strategy exhibits high DOX loading efficiency owing to the superchaotropic effect of boron cluster and enhanced immunolabeling efficiency by the thorough mixing of 3D scaffold. Meanwhile, the novel magnetoresponsive electrode enables magnetic separation and real-time, enzyme-linked immunoelectrochemical quantification of exosomes, thereby simplifying the workflow from drug loading to quantification. The resulting EDB in combination with magnetic hyperthermia achieves up to 90% cell-killing efficiency against DOX-resistant breast cancer cells. Overall, our system could simultaneously realize the enhanced DOX loading into exosomes, efficient magnetic immunoseparation of exosomes, and sensitive electrochemical quantification of exosomes, offering a promising approach for autologous exosome-based drug delivery for cancer treatment.
研究领域:
生物医学工程
·
癌症治疗
·
纳米技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）