Molecular Catalysis
·
2018
·
IF 0
Yanting Guo,Xing Chen,Xuan Zhang,Shujin Pu,Xutong Zhang,Chengli Yang,Dali Li
The immobilization of enzyme is an important biotechnology in industry. Enzyme immobilization by nanomaterials has attracted interest of researchers due to potentially promising application. Many enzymes had been successfully immobilized by different nanomaterials. In this work, β-glucosidase was immobilized by SiO 2 nanoparticles (nano-SiO 2 ) and zeolitic imidazolate framework-8 (ZIF-8), then the enzymatic properties of them were also compared. The nano-SiO 2 @β-glucosidase and the β-glucosidase@ZIF-8 achieved immobilization yield of 58.5% and 23.0%, respectively. Optimal temperature of the free β-glucosidase, nano-SiO 2 @β-glucosidase and the β-glucosidase@ZIF-8 were around 50 °C. Both free β-glucosidase and nano-SiO 2 @β-glucosidase showed maximal catalytic activity at pH 6.0, while the optimal pH of the β-glucosidase@ZIF-8 was 5.4 roughly. The nano-SiO 2 @β-glucosidase exhibited similar pH stability and thermal stability to those of the free β-glucosidase, and the β-glucosidase@ZIF-8 improved pH stability greatly. Moreover, after the treatment of trypsin for 4 h at 37 °C, the residual activities of the β-glucosidase@ZIF-8 was the highest that retained 94%, which provided huge potential for the application of the β-glucosidase@ZIF-8 in industry. Furthermore, the nano-SiO 2 @β-glucosidase and the β-glucosidase@ZIF-8 can be reused for 5 cycles with 87.5% and 88.7% residual activity, respectively.
研究领域:
生物技术
·
酶工程
·
纳米材料科学
✓ 已验证
产品关联
DOI
CARBOHYDRATE POLYMERS
·
2023
·
IF 11.2
Yunshan Liu,Jianzhong Jiang
β -ionone has a unique violet odor and good biological activity, which is an essential fragrance component and potential anticancer drug. In this paper, β -ionone was encapsulated using complex coacervation of gelatin and pectin, followed by cross-linking with glutaraldehyde . The pH value, wall material concentration, core-wall ratio, homogenization conditions, and curing agent content were investigated in the single-factor experiments. For example, the encapsulation efficiency increased with the homogenization speed, which reached a relatively high value at 13000 r/min for 5 min. The gelatin/pectin ratio (3:1, w / w ) and pH value (4.23) significantly affected the size, shape, and encapsulation efficiency of the microcapsule. The fluorescence microscope and SEM were used to characterize the morphology of the microcapsules, in which the microcapsule has a stable morphology, uniform size, and spherical multinuclear structure. FTIR measurements confirmed the electrostatic interactions between gelatin and pectin during complex coacervation . Thermogravimetric analysis (TGA) revealed that the microcapsules could maintain good thermal stability over 260 °C. The release rate of β -ionone microcapsule was only 20.6 % after 30 days at the low temperature of 4 °C. These findings provide an effective carrier to deliver flavors like β -ionone and could be useful in the fields of daily chemicals and textiles.
研究领域:
食品科学
·
材料科学
·
香料化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Coatings
·
2023
·Vol. 13
·期 2
·422
·
IF 3.4
Haoyang Ni,Haiwei Fu,Hongbiao Wang,Hongwen Zhang,Yifan Zhu,Xiuqing Fu
This study aimed to improve the surface hardness and wear resistance of spindle hook teeth with special shapes to reduce the cost of replacing the spindle on cotton pickers. For this goal, a Ni-Co-β-SiC composite coating with different concentrations of β-SiC nanoparticles (0, 1, 2, 3, and 4 g/L) was electrodeposited on the surface of spindle hook teeth. The hardness, elemental composition, and micromorphology of the spindle hook teeth were characterized by microhardness tests, an energy spectrum analyzer, and a scanning electron microscope after cutting with the spindles. The actual wear process of the coating was determined by wear simulation and scratch wear tests, and the effect of the concentration of β-SiC nanoparticles on the properties of the coating was investigated. The results show that Ni-Co-β-SiC composite coating has a typical cellular structure. The hardness first increases and then decreases, and the wear resistance (including friction coefficient, scratch area, and shape of wear area) first decreases and then increases, mainly due to the pinning role and agglomeration of β-SiC nanoparticles. When the concentration of β-SiC was 1 g/L, the hardness reached a maximum of 506.2 HV0.1, the coefficient of friction reached a minimum of 0.13, and the wear area and wear micromorphology reached the most suitable values. Therefore, this Ni-Co-β-SiC composite coating had the best microhardness and wear resistance.Keywords:spindle hook teeth;β-SiC nanoparticles;Ni-Co-β-SiC composite coatings;wear;microhardness;electrodeposition
研究领域:
材料科学
·
机械工程
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产品关联
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2011
·Vol. 123
·期 3
·1675-1683
·
IF 1.24
Nianjun Kang,Zhongjie Du,Hangquan Li,Chen Zhang,Zhehan Zhao
A series of β-cyclodextrin-based epoxy resins were synthesized with different epoxy equivalent weights. Their chemical structures were characterized with Fourier Transform Infrared Spectroscopy (FTIR) and Nuclear Magnetic Resonance Spectroscopy (NMR) examination. These epoxy resins were cured using L -arginine as a curing agent, and the degradation behavior of the cured resins was evaluated under different acidic buffer solutions at 37°C. The degradable behavior of such epoxy resins suggested potential applications as environment friendly materials. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
研究领域:
材料科学
·
化学工程
✓ 已验证
DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
·
2024
·
IF 8.4
Xinli Zhang,Shoutao Gong,Long Han,Quan Jin,Xiaoming Yan,Gaohong He,Fengxiang Zhang
Polyarylpiperidinium anion exchange membranes (AEMs) have been widely studied in anion exchange membrane fuel cells and alkaline electrolyzed water due to their excellent alkali resistance stability. In this work, we report the design and fabrication of poly(p-triphenylene-piperidinyl) (PTP) AEMs quaternized and cross-linked by bromo-β-cyclodextrin (β-CD-Br 7 ). In this type of membranes, the densely cross-linked and quaternized sites derived from β-CD-Br 7 can help to construct continuous ion transport channels to facilitate ion conduction. Although the ion exchange capacity (IEC) tended to decrease with increasing cross-linking degree, the qPTP-CD 5 membrane with 5 % cross-linking (IEC = 2.3 mmol g −1 ) produced the most significant microphase separation and the highest conductivity (125.6 mS cm −1 at 80 °C). The membrane also exhibited impressive alkaline stability, with 94.6 % conductivity retention in 1 M NaOH at 80 °C after 1000 h and 90.7 % conductivity retention after 1500 h. Finally, the peak power density of the fuel cell assembled with qPTP-CD 5 membranes was 1.216 W cm −2 at 80 °C and there was no significant voltage degradation when operated at 200 mA cm −2 current density for 40 h. This work demonstrates that β-CD can function as a good “platform” for simultaneous cross-linking and quaternization to fabricate high performance AEM.
研究领域:
材料科学
·
能源科学
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2019
·
IF 4.784
Sidra Naseer,Jie Ouyang,Xing Chen,Shujin Pu,Yanting Guo,Xuan Zhang,Dali Li,Chengli Yang
Nanoparticles have been successfully used for immobilization of different enzymes . The enzyme immobilized by nanomaterials has promising application in the biotechnological industry. The β-glucosidase is very important in industrial field. The immobilization of β-glucosidase by nanomaterials increases its activity and reusability. In this work, the β-glucosidase was extracted from fruiting bodies of Agrocybe aegirit and was purified by anion exchange . The β-glucosidase was immobilized by SiO 2 nanoparticles (nano-SiO 2 ) crosslink with glutaraldehyde (GA). On the other hand, the β-glucosidase firstly immobilized by process adsorption and then crosslink with genipin (GP) which was produced by the hydrolysis of geniposide by β-glucosidase. Then we compared the properties of both immobilized GA-crosslinked β-glucosidase and GP-crosslinked β-glucosidase, their immobilization yields were 83.34% and 96.29% respectively. The GA-crosslinked β-glucosidase and free β-glucosidase revealed optimal pH at 6.0. The optimal pH of GP-crosslinked β-glucosidase was ranging between 4.5 and 7.5. The GA-crosslinked β-glucosidase and GP-crosslinked β-glucosidase revealed the optimal temperature at 50 °C, 70 °C respectively. For the free β-glucosidase, the optimal temperature was 55 °C. Furthermore, the GA-crosslinked β-glucosidase and GP-crosslinked β-glucosidase were characterized by scanning electron microscope (SEM). The geniposide consumption in the reaction system of GA-crosslinked β-glucosidase was analyzed by high performance liquid chromatography (HPLC).
研究领域:
生物技术
·
酶学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
·
2018
·Vol. 20
·期 23
·15835-15840
·
IF 3.906
Jianning Jin,Hua Yu,Liying Guo,Jinjin Liu,Bing Wu,Yuao Guo,Yuting Fu,Lijuan Zhao
β-NaREF4 (RE: rare earth metals) is a peculiar crystal due to its intriguing disordered structure. This crystal is usually considered to have an average structure with a space group of P-6 (174). However, a long-term contradiction existing in this system is that the luminescence characteristics do not match the corresponding theoretical predictions based on the average structure. To resolve this contradiction, we proposed a reasonable local structure model clearly showing the local symmetry of the cations based on the measurement of the extended X-ray absorption fine structure of β-NaGdF4. We also observed an intrinsic distortion in the disordered structure that resulted from the disordered arrangement of the Na+ and Gd3+ cations. Furthermore, using Eu3+ as a photoluminescence probe, we concluded that the breakdown in the crystallographic site symmetry originated from the intrinsic distortion of these crystals. This work provides a comprehensive explanation for the contradiction observed in this system and a foundation for further investigations to understand such disordered structures.
研究领域:
材料科学
·
晶体学
·
光谱学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CERAMICS INTERNATIONAL
·
2017
·
IF 2.986
Shenglei Feng,Fupo He,Jiandong Ye
In this study, for the first time honeycomb β-tricalcium phosphate (β-TCP) scaffolds were fabricated through an extrusion technique. The physicochemical properties and cell behaviors of the honeycomb β-TCP scaffolds were investigated. The results showed that scaffolds were characterized by ordered channel-like macropores and unidirectional interconnection. The pore structure and mechanical strength could be tailored by changing the parameters of extrusion molds. The pore size of scaffolds was in the range of 400–800 µm approximately, while their compressive strength parallel to the pore direction and porosity ranged from 14 to 20 MPa and 60–70%, respectively. The in vitro cell behavior demonstrated that cells could well attach on the surfaces and grow into the inner channel-like pores of the scaffolds; the scaffolds with higher porosity showed better cell proliferation but poorer cell differentiation. The honeycomb scaffolds fabricated by extrusion technique are potential candidate for bone tissue engineering.
研究领域:
生物材料学
·
组织工程学
✓ 已验证
产品关联
DOI
高影响因子
BIOMACROMOLECULES
·
2021
·
IF 6.988
Wenshi Xu,Yong Chen,Bing Zhang,Wenwen Xu,Jie Niu,Yu Liu
Supramolecular assembly loading drug as biomedical materials is a research hotspot. Herein, we reported a supramolecular electrospun assembly constructed via the hydrophobic and hydrogen bonding interaction. The obtained results showed that the assembly by supramolecular electrospinning not only increased the interactions of multiple antibacterial active species including antibiotics, cationic polymers, and silver to form a flexible membrane with good mechanical strength but also indicated the dual effects of rapid doxycycline and polyethyleneimine release as well as a sustained Ag release. Interestingly, the assembly showed not only good degradability but also a high bacteriostatic efficacy toward Escherichia coli (E. coli) up to 99.9%. More importantly, the in vivo wound healing assay indicated that the assembly could promote the healing of uninfected, E. coli-infected, and even methicillin-resistant staphylococcus aureus-infected wounds. The current research provides a novel approach to construct a supramolecular assembly by electrospinning mechanically induced strong noncovalent interaction.
研究领域:
生物材料学
·
药剂学
·
微生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
RSC Advances
·
2023
·Vol. 13
·期 9
·5667-5673
·
IF 3.9
Bin Li,Haibo Qin,Ming Ma,Xiaojia Xu,Mengjing Zhou,Wenrui Hao,Zhigang Hu
In this paper, betaine (Bet) was used as a hydrogen bond acceptor (HBA), and acrylic acid (AA) and acrylamide (AM) were used as hydrogen bond donors (HBD) and mixed to form a deep eutectic solvent (DES). Different concentrations of β-cyclodextrin (β-CD) were dispersed in the DES, and a novel β-CD/P(AA-co-AM) hydrogel was prepared by frontal polymerization (FP). The characteristic structure and morphology of the hydrogels were analyzed using Fourier transform infrared (FTIR) spectroscopy and scanning electron microscopy (SEM), and the properties of the hydrogels were investigated. The results show that the mechanical properties of the hydrogel were improved by β-CD acting as a second cross-linking agent in the polymerization process, thus increasing the cross-link density of the hydrogel. Because the carboxyl groups contained in the acrylic acid dissociate under alkaline conditions, the composite hydrogel shows excellent pH responsiveness under alkaline conditions. Tetracycline hydrochloride was used as a drug model to test the drug loading and drug release performance of the hydrogels. With the increase of β-CD content, the loading capacity of the hydrogels for tetracycline hydrochloride gradually increased. The data of drug release indicated that the hydrogel has good drug delivery performance and has promising applications in drug delivery systems and other areas.
研究领域:
材料科学
·
药学
·
化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
·
2020
·
IF 4.192
Yulin Fan,Fang Fu,Langqiu Chen,Jiping Li,Jing Zhang
Dioxyethene fragment (−(OCH2CH2)2−) was introduced into traditional alkyl β-d-glucopyranosides to ameliorate the water solubility, and eight nonionic surfactants, that is, alkoxy ethoxyethyl β-d-glucopyranosides with alkyl chain lengths (n = 6–16), were synthesized and characterized. Their hydrophilic and lipophilic balance number, water solubility, critical micelle concentration (cmc), γcmc, Γmax, and hygroscopic rate decreased with an increase in the alkyl chain length. Hexadecoxy ethoxyethyl β-d-glucopyranoside had no water solubility at 25 °C. Decoxy ethoxyethyl β-d-glucopyranoside had the best emulsifying property in the toluene/water and n-octane/water systems and the strongest foaming property, whereas dodecoxy ethoxyethyl β-d-glucopyranoside had the best emulsifying property in the rapeseed oil/water system. Such β-d-glucopyranosides (n = 6–12) exhibited excellent surface activity. In addition, for the binary mixture of alkoxy ethoxyethyl β-d-glucopyranosides (n = 8, 10, 12) and sodium dodecyl sulfate or cetyl trimethyl ammonium chloride, their cmc values were lower than the pure β-d-glucopyranosides, indicating that they had synergistic interactions. The fan focal conic textures of alkoxy ethoxyethyl β-d-glucopyranosides (n = 7–16) were observed during the cooling process under a polarizing optical microscope. Alkoxy ethoxyethyl β-d-glucopyranosides (n = 14, 16) had the related melting points and the clear points with differential scanning calorimetry. With β-d-glucopyranosides (n = 6–16) and n-butanol as the surfactant and cosurfactant, respectively, and with cyclohexane as the oil phase, the related microemulsion areas in their pseudoternary phase diagram system were investigated with the visual observation at 25 °C. Along with the slashing requirements of petroleum consumption, environmental protection, and green and sustainable development, nonionic sugar-based alkoxy ethoxyethyl β-d-glucopyranosides should be expected to have their potential practical application because of their strengthened hydrophilicity, improved water solubility, and enhanced surface activity.
研究领域:
化学
·
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Soft Matter
·
2012
·Vol. 8
·期 14
·3856-3863
·
IF 4.39
Hua-Neng Xu,Shu-Feng Ma,Wei Chen
The effect of β-cyclodextrin (β-CD) on the aggregation behavior of a nonionic surfactant, Triton X-114 ((1,1,3,3-tetramethylbutyl)phenyl-polyethylene glycol), in aqueous solutions has been studied as a function of temperature by means of turbidity, dynamic light scattering (DLS), transmission electron microscopy (TEM), and rheo-small angle light scattering (rheo-SALS). The Triton X-114 (TX-114) solutions possess unique structural variations and display special aggregate transitions upon β-CD addition. In contrast to the reported aggregate disruption effect of β-CD for dilute nonionic surfactant solutions, aggregate growth is found in the aqueous TX-114 solutions of 93 mM upon β-CD addition. The micelle to vesicle transition induced by β-CD addition, which can greatly influence the turbidity and the viscosity of the solutions, is quantified by the characteristic length and aspect ratio of the aggregates. The characteristic length and aspect ratio of the aggregates change significantly after β-CD addition. It shows that aggregate growth may occur in nonionic surfactant–CD systems, as well as the reported ionic surfactant–CD systems. It is proposed that the CD–CD H-bonds create intermicelle interactions and promote aggregation of the CD/surfactant complexes, resulting in the formation of micrometer-scale phase-separated droplets.
研究领域:
化学
·
材料科学
·
生物物理学
✓ 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）