JOURNAL OF THE AMERICAN CERAMIC SOCIETY
·
2019
·Vol. 103
·期 2
·1372-1384
·
IF 3.094
Lingyu Jia,Peigang He,Dechang Jia,Shuai Fu,Meng Wang,Meiling Wang,Xiaoming Duan,Zhihua Yang,Yu Zhou
To date, geopolymer has emerged as a promising and inexpensive precursor with potential application in trapping hazardous elements via physical encapsulation or chemical bonding. In this work, different high-temperature products derived from Sr-contained geopolymer precursors were prepared. Different to conventional hazardous elements that immobilized in the geopolymer precursor, which show decreasing leaching rates after high-temperature treatments, leaching rates of Sr in the resulting high-temperature products first increase and then decrease with the increasing heating temperature. Herein, we first shed light on the underlying reasons of such temperature-dependent leaching behaviors by investigating effects of heating temperature on the phase composition, microstructure, and immobilization mechanism. Moreover, a novel immobilization strategy has been proposed based on the blocking effect of formed nepheline structures at 1200°C. Using this strategy, the leaching rate of Sr reduced to 5.82 × 10 −7 g cm −2 d −1 in the deionized water.
研究领域:
材料科学
·
环境科学
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DOI
高影响因子
COLLOIDS AND SURFACES B-BIOINTERFACES
·
2018
·
IF 3.997
Mingbo Ji,Xiangrong Chen,Jianquan Luo,Yinhua Wan
Two anticoagulant proteins, nattokinase and lumbrokinase, were successfully immobilized onto the dopamine-coated polysulfone (PSf) membrane surface by covalent bonding. X-ray photoelectron spectroscopy (XPS) and Zeta potential measurement confirmed the immobilization of these anticoagulant proteins. The immobilization yield of nattokinase and lumbrokinase reached to 35.2 and 33.4 μg/cm 2 , respectively. The water contact angle measurement revealed that the membrane surface hydrophilicity was improved after immobilizing the anticoagulant proteins. Meanwhile, the immobilized proteins retained their biological activity. Then blood compatible tests demonstrated that the modified membranes had lower static protein adsorption, platelet/erythrocyte adhesion, hemolysis, as well as longer blood clotting time, compared to virgin PSf membrane. In addition, the nattokinase-immobilized membrane showed a higher blood compatibility than BSA and lumbrokinase immobilized memrbanes, due to its’ high bioactivity. Our research demonstrates that the dopamine-assisted immobilization of nattokinase and lumbrokinase can endow the membranes with improved blood compatibility as well as high biological activity, which may be expected to apply to blood-contacting materials.
研究领域:
生物材料
·
生物医学工程
·
血液相容性
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产品关联
DOI
PubMed
高影响因子
RSC Advances
·
2016
·Vol. 6
·期 80
·76855-76860
·
IF 3.289
Chao Yang,Haodao Mo,Limin Zang,Jian Chen,Zhenqiang Wang,Jianhui Qiu
An attapulgite@chitosan (ATP@CS) nanocomposite was prepared by coating chitosan onto naturally needle-like nanoscale attapulgite clay. The nanocomposite was characterized by scanning electron microscopy, Fourier transform infrared spectroscopy and thermogravimetric analysis. Cellulase was covalently immobilized on this ATP@CS support using glutaraldehyde activation method and compared to (3-aminopropyl) triethoxysilane modified ATP (ATP–APTES) support. The amount of cellulase on the ATP@CS and ATP–APTES was 88.3 and 76.5 mg g−1, respectively. The reusability and effects of pH and temperature on activity were studied. The ATP@CS immobilized cellulase exhibited higher pH and thermal stability as well as good reusability compared to the ATP–APTES immobilized cellulase and the free cellulase. The immobilized cellulase samples were also utilized to hydrolyze wheat straw to evaluate their potentially practical applications.
研究领域:
生物化学
·
材料科学
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产品关联
DOI
高影响因子
Journal of Materials Chemistry A
·
2014
·Vol. 2
·期 43
·18339-18344
·
IF 0
Zhiming Chen,Wenhui Xu,Li Jin,Juanjuan Zha,Tingxian Tao,Ying Lin,Zhilin Wang
Amine-functionalized Fe3O4@C nanoparticles have been successfully synthesized on a large scale via a solvothermal route. The morphology, structure and properties of the Fe3O4@C nanoparticles were investigated through different analytical tools. Due to the magnetic nature and the presence of amine-functionalized groups, the as-prepared Fe3O4@C nanoparticles were employed as magnetic carriers for lipase immobilization. Our results indicate that the lipase loading amount on the magnetic Fe3O4@C nanoparticles was about 115.6 mg of protein per g. The factors related to the catalytic activity of the immobilized lipase on the magnetic carriers were systematically investigated. Hydrolytic activity tests reveal that the immobilized lipase retains about 93% of the free enzyme activity. It should be mentioned that the thermal stability of the immobilized lipase was strikingly higher than that of the free lipase. Most importantly, the immobilized lipase retained more than 68% of its initial activities after 10 times reuse. It is hoped that the amine-functionalized Fe3O4@C nanoparticles may find an application in biotechnology and catalysis.
研究领域:
生物技术
·
催化科学
✓ 已验证
产品关联
DOI
APPLIED BIOCHEMISTRY AND BIOTECHNOLOGY
·
2014
·Vol. 172
·期 6
·3128-3140
·
IF 1.687
Zhang Wei-Wei,Wang Na,Zhang Ling,Wu Wan-Xia,Hu Cheng-Li,Yu Xiao-Qi
An inexpensive, facile, and environmentally benign method was developed to improve the activity and stability of Candida rugosa lipase (triacylglycerol acylhydrolase) immobilized on microemulsion-based organogels (CRL MBGs) via the addition of additives during immobilization. The additives used were polyethylene glycol (PEG) or polysaccharides. This study is the first report on the effect of additives in CRL MBGs. Among the tested additives, PEG produced the most improvement in the immobilized CRL, enhancing its stability in organic solvents (specifically polar solvents). The results of circular dichroism and fluorescence spectra experiments indicated that exposure of the acidic CRL to electronegative additives in the buffer, such as polyethylenimine and the electropositive surfactant cetyltrimethylammonium bromide, may change the lipase secondary structure, ultimately causing enzyme inactivation. However, sodium bis(2-ethylhexyl)sulfosuccinate and PEG 2000 had minimal effects on the secondary structure of CRL. The CRL MBGs containing PEG 2000 demonstrated remarkable retention of their catalytic activity during the recycling test. No significant changes in enzymatic activity were observed, even after nine runs, and 90 % of the original yield was maintained after 15 cycles.
研究领域:
生物技术
·
酶学
·
化学工程
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF PEPTIDE SCIENCE
·
2022
·Vol. 28
·期 10
·e3411
·
IF 2.408
Shu Bai,Jie Zhang,Liyan Zhu,Xiaoxing Gong,Linling Yu,Yan Sun
Oriented immobilization of antibodies is important for the effective recognition of target antigens. In this paper, a heptapeptide ligand, HWRGWVC (HC7), was modified onto non-porous monosized poly(glyceryl methacrylate) (pGMA) microspheres (named pGMA-HC7) to explore the antibody immobilization behaviors. Characterization of the microspheres by particle size analyzer, scanning electron microscopy, Fourier transform infrared spectroscopy, and reversed-phase chromatography proved the success of each fabrication step. The capacity and activity of antibody immobilization through HC7 were studied using immunoglobulin G (IgG) as a model antibody and horseradish peroxidase (HRP) as a model antigen. Additionally, IgG immobilizations on pGMA microspheres by nonspecific adsorption and covalent coupling through carbodiimide chemistry were conducted for comparison. pGMA-HC7 exhibited an IgG adsorption capacity of 3–4 mg/g in 10 min by the specific binding of HC7 without nonspecific interactions. Notably, the ligand HC7 showed a by two orders of magnitude stronger affinity for IgG than its original hexapeptide ligand HWRGWV. Moreover, the capacity and activity of the immobilized anti-HRP antibody on pGMA-HC7 were 1.6-fold and 3-fold higher than those of the covalent coupling, respectively. The results proved the superior role of HWRGWVC in the affinity binding of antibody and the potential of pGMA-HC7-25 in immunoassay and immunodiagnostic applications.
研究领域:
生物化学
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生物技术
·
材料科学
·
免疫学
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产品关联
DOI
PubMed
高影响因子
ACS Omega
·
2023
·
IF 4.1
Hong Zhang,Xin Zhang,Lei Wang,Bo Wang,Xu Zeng,Bo Ren,Xiaodong Yang
A novel lignin-enhanced graphene aerogel (LGA) was prepared by one-step hydrothermal synthesis, and lipase from Pseudomonas sp. (PSL) was immobilized on LGA successfully by interfacial activation. The catalytic activity and enantioselectivity of LGA-PSL for the preparation of (S)-2-octanol by an enantioselective transesterification were improved obviously. The characterization of LGA and LGA-PSL was performed. X-ray diffraction and Fourier transform infrared spectroscopy demonstrated the formation of numerous electrostatic and hydrogen bonds between lignin and graphene in the aerogel structure. In addition, the specific surface area pore size analyzer (BET) test proved that the introduction of lignin significantly increased the specific surface area and pore size of the aerogel material, which improved the immobilization efficiency of lipase in the aerogel. The introduction of lignin has changed the original lamellar structure of the graphene oxide (GO) aerogels. The lignin cross-linked with the GO lamellae through hydrogen bonding, causing a porous structure to form between the original lamellae, thus increasing their specific surface area. The immobilized lipase (LGA-PSL) was used for the preparation of (S)-2-octanol by an enantioselective transesterification, and the reaction conditions for this enzymatic transesterification had been optimized. LGA-PSL exhibited a high catalytic performance and could be reused four times in this reaction. Based on these results, LGA as an immobilization carrier had potential applications in the industrial application of lipase.
研究领域:
材料科学
·
生物催化
·
酶工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ENVIRONMENTAL TECHNOLOGY
·
2022
·
IF 3.475
Zhongqiu Luo,Weihong Mu,Xintao Zhou,Zhuo Chen
Removal and immobilization of highly toxic arsenic form industrial wastewater using simple and effective methods is of important practical significance. Although the formation of natroalunite phase NaAl3(SO4)2(OH)6 has been demonstrated to be an effective method for arsenic immobilization in model system with chemical reagent grade arsenates as arsenic source, the further study is needed to investigate its immobilization for real industrial wastewater. This work reported the synthesis of natroalunite phase NaAl3(SO4)2(OH)6 using arsenic-containing industrial wastewater from benzyl acid production. The synthesis temperature and time were optimized to obtain the pure natroalunite phase composites with high crystallinity. When n(Al/As)aq was greater than 3.0, the arsenic could almost precipitate exclusively as natroalunite phase after 60 min hydrothermal reaction at 200°C, with a maximum arsenic immobilization amount of 7.0 mol%. A maximum leaching concentration of 0.50 mg/L was observed at pH = 3.0 during the short-term (24 h) leaching test, which was lower than the US EPA TCLP test limit of 1 mg/L. The long-term leaching test up to 90 days revealed that the arsenonatroalunite could be a safe immobilization material for arsenic in pH 5.0–8.0 environments.
研究领域:
环境科学
·
化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
MOLECULAR CRYSTALS AND LIQUID CRYSTALS
·
2023
·
IF 0.7
Zihao Meng,Jian Wu,Qingyun Li,Youyan Liu,Aixing Tang
Lipase OF from Candida cylindracea was adsorbed onto surfactant-modified Na-bentonite (Bent), and the effects of the surfactants on the catalytic properties of immobilized lipase were studied in detail. The results showed that both the specific activity and enzyme loading of immobilized lipase varied significantly with modified support of different surfactants. The highest specific activity was obtained with Tween20-modified Bent: 11.9-fold higher than the non-modified sample. Upon modification by a single surfactant, two kinds of surfactants were combined to process the modification. It was surprising to find that the enzyme immobilized on CTAB (60%) and TX-100 (40%) co-modified Bent yielded a specific activity recovery of 133.4% indicating that the enzyme might be “activated”. Kinetic analyses for the hydrolysis of p-nitrophenyl palmitate (p-NPP) showed that Km decreased from 5.57 mg mL−1 of free lipase to 3.43 mg·mL−1 and Vmax increased 1.35-fold higher. The structure, surface morphology, and hydrophobicity of the modified bentonite and immobilize lipase were characterized via X-ray diffraction, Fourier transform-infrared spectroscopy, scanning electron microscopy, and contact angle measurements. We assumed that lipase molecules may be bound to the surface of the carrier, and the surface hydrophobicity and the change of the functional group caused by the modification of surfactant may be the key factor affecting lipase immobilization.
研究领域:
生物化学
·
酶工程
✓ 已验证
产品关联
DOI
高影响因子
PROCESS BIOCHEMISTRY
·
2023
·
IF 4.4
Meng Qiao,Junjie Zhang,Jingmin Li,Lu Xing,Xue Zhou,Yunchang Xie,Xing Zhang
Hyaluronic acid (HA) and chondroitin sulfate (CS) are polydisperse glycosaminoglycans (GAGs),which have important applications as health care products and drugs in skin beauty and arthritis prevention. Enzymatic synthesis is a significant strategy to obtain oligosaccharides and polysaccharides with uniform chain length and well-defined structure. However, the limitations of glycosyltransferase , such as low expression, poor stability, and difficulty in reuse, greatly restrict its application in large-scale commercial production. In this study, we constructed the expression system for hyaluronic acid synthase PmHAS and chondroitin synthase KfoC to obtain the enzyme with high expression level and good water solubility. Subsequently, we screened and optimized several highly biocompatible metal-organic frameworks (MOFs) to immobilize two glycosyltransferases efficiently. The resulting enzyme@MOF composite can catalyze the synthesis of hyaluronic acid and chondroitin oligosaccharides/polysaccharides in quantitative yield. Meanwhile, the supramolecular interactions between enzyme and hydrophilic MOFs confer satisfactory stability, durability, and reusability on immobilized PmHAS and KfoC.
研究领域:
生物技术
·
生物化学
·
材料科学
·
药学
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2023
·
IF 5.2
Jiajing Li,Dandan Zhao,Yisheng Chen,Zhongxiang Guo,Hongyue Lei,Hui Dan,Yi Ding,Tao Duan
The development of matrix with high capacity and stability immobilization of nuclear waste is highly desirable. Herein, new type of zircon-based borosilicate glass-ceramics (ZBGC) with high immobilization capacity and excellent aqueous stability was prepared and applied to immobilize simulated trivalent actinide (Nd). The effects of Nd doping and sintering temperature on the microstructure and phase composition of the obtained ZBGC were researched. The experimental suggested that high ZrSiO 4 formation rate (97.49 wt%) was obtained by tuning the Nd content and sintering temperature. The record high immobilization capacity of Nd in ZGBC (18 at%) was achieved owing to the synergistic effect between the crystal lattice and glass network immobilization. Additionally, the obtained Nd-doped ZBGC exhibited excellent aqueous stability (∼10 −6 g m −2 d −1 ) due to the high compactness. The results demonstrated that ZBGC with high immobilization capacity and aqueous stability could be potential matrix for actinides immobilization.
研究领域:
材料科学
·
核化学与放射化学
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2025
·Vol. 51
·期 26
·49745-49753
·
IF 5.6
Yusen Xing,Rugeng Liu,Wei Han,Mei Li
Zircon (ZrSiO 4 ), due to its excellent thermal stability and chemical durability, is an efficient solidification matrix for high-level radioactive waste (HLW). However, the traditional solid-state method has problems such as high synthesis temperature (>1600 °C), long reaction time (>24 h), and insufficient product purity. Thus in this study, the synthesis conditions were optimized to 1400 °C/6 h by adding 10 wt% MgO as a mineralizer, significantly reducing the reaction temperature and time. The mechanism of MgO as a mineralizer was investigated. XRD revealed that MgO promoted the transformation of m-ZrO 2 (monoclinic zirconia) to t-ZrO 2 (tetragonal zirconia) and reacted with SiO 2 to form MgSiO 3 , jointly lowering the reaction temperature and time. Based on this, the lattice substitution strategy was used to immobilize Sm 3+ (simulating trivalent actinides) in Sm x Zr (1-x) SiO 4 (0 < x < 0.5) solid solutions. XRD indicated that when x ≤ 0.45, a stable coexistence phase of Sm x Zr (1-x) SiO 4 (zircon structure) and m-ZrO 2 (monoclinic zirconia) was formed, and Sm 3+ successfully replaced Zr 4+ . When x > 0.45, the structure collapsed, with peak broadening and the appearance of a second phase. The maximum component (x = 0.45) was combined with borosilicate glass to prepare glass-ceramic solidification bodies. In the 90 °C static leaching test, the 28-day normalized leaching rate of Sm 3+ ( LR Sm ) was ∼10 −6 g m −2 d −1 . This strategy provides a new solution for the long-term immobilization of fission element.
研究领域:
材料科学
·
核废料管理
·
陶瓷学
·
固态化学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）