SENSORS AND ACTUATORS B-CHEMICAL
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2011
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IF 3.37
Cheng Fang,Jishan He,Zhencheng Chen
A disposable amperometric biosensor for detecting the total cholesterol was fabricated which comprises a sensing electrode and a reference electrode in simultaneous contact with an integrated reagent layer. The integrated reagent layer formed by coating a working ink containing cholesterol esterase, cholesterol dehydrogenase, coenzyme , redox mediator , surfactant, stabilizer, filler and at least one aqueous thickening agent . The biosensor showed the linearity for 50–500 mg/dL cholesterol acetate. The minimum detection limit of the cholesterol was 50 mg/dL. The effects of temperature and the stability of immobilized enzymes were also studied. A good correlation was found among cholesterol values obtained by commercial colorimetric test strip and clinical/laboratory methods. The biosensor showed an acceptable reproducibility, good stability and low interferences.
研究领域:
生物医学工程
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分析化学
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DOI
高影响因子
Catalysts
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2021
·Vol. 11
·期 10
·1158
·
IF 4.146
Zhanyong Wang,Tingting Su,Jingjing Zhao
Genipin was used as a crosslinking agent to prepare magnetic genipin-crosslinked chitosan beads, which were then used as a carrier for immobilizing recombinant cutinase fromFusarium solani(FSC) to obtain immobilized FSC. The optimal temperature for the immobilized FSC was 55 °C, which was 5 °C higher than that of the free enzyme, whereas its optimal pH was increased from 8.0 to 9.0; this indicates that the immobilized FSC had improved pH and thermal stability. After repeated use for 10 cycles, the activity of the immobilized FSC remained at more than 50%; after being stored at 4 °C for 30 days, its activity was still approximately 88%. We also found that the Km of the immobilized FSC was higher than that of the free enzyme. These results indicate that the performance of FSC was improved after immobilization, which is an important basis for the subsequent application of FSC in industrial production.Keywords:immobilization;cutinase;chitosan;genipin
研究领域:
生物技术
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酶学
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材料科学
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产品关联
DOI
高影响因子
TEXTILE RESEARCH JOURNAL
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2020
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IF 1.926
Yawei Wang,Yun Bai,Tong Shu,Pei Fan,Huashan Zhang,Ossi Turunen,Hairong Xiong,Longjiang Yu
A novel versatile glycoside hydrolase Cel5M was identified from Pectobacterium carotovorum and used in ramie degumming. The full-length Cel5M (GenBank: MH544226) containing the catalytic domain Cel5MD and its carbohydrate-binding module (CBM3) were expressed in E. coli. Both Cel5M and Cel5MD showed a broad substrate spectrum cleaving konjac glucomannan (KGM), carboxymethylcellulose (CMC) and oat spelt xylan. The optimal temperature of Cel5MD was 55oC with CMC and KGM, whereas the optimum temperature of Cel5M was 65oC with KGM and 60oC with CMC. The improved thermal activity with KGM was probably reflected also in the much lower Km with KGM than with CMC, indicating stronger binding of the full-length enzyme with KGM. Both enzymes were highly stable over a broad pH range from pH 5.0 to 9.0 with KGM. The use of the Cel5M enzyme together with the wild-type P. carotovorum HG-49 strain showed significant improvement when compared to using the mere strain HG-49 for application in ramie degumming. Moreover, the whole P. carotovorum Cel5M gene was over-expressed in P. carotovorum HG-49 itself to improve the ramie-degumming capacity. Altogether, this study indicates that in situ production of processing enzymes could be utilized in the textile industry.
研究领域:
生物技术
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酶学
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纺织科学
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产品关联
DOI
高影响因子
JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
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2024
·
IF 5.7
Chaochao Chen,Liang Luo,Jianzhong Shen,Zhanhui Wang,Yantong Pan
The enzyme-linked immunosorbent assay (ELISA) stands as one of the most frequently employed rapid detection techniques for both chemical and biological contaminants. Horseradish peroxidase (HRP) and hydrogen peroxide (H2O2), serving as signal generators, play indispensable roles throughout the entire ELISA process. However, HRP and H2O2 exhibit high sensitivity to elevated temperatures, hindering the broader utilization and transportation of ELISA. Hereby, being inspired by the cascade catalysis of glucose by glucose oxidase (GOx) and HRP as well as the advantageous properties of metal–organic frameworks (MOFs), we developed a cascade catalysis-based competitive fluorescent ELISA (CCF-ELISA) for mycotoxin detection in maize using zearalenone (ZEN) as a model. The results revealed the remarkable protective effects of MOFs on enzymatic activities. Based on upon characteristics, the built CCF-ELISA enabled the detection of ZEN with a half-maximal inhibitory concentration of 0.54 ng/mL and allowed a detection range from 0.19 to 1.51 ng/mL. When applied to naturally contaminated maize samples, the outcomes obtained from the CCF-ELISA showed a high level of comparability with high-performance liquid chromatography–tandem mass spectrometry, demonstrating the promising potential of the developed CCF-ELISA in the rapid detection for food security.
研究领域:
食品安全检测
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生物化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Sustainable Chemistry & Engineering
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2024
·
IF 7.1
Ping-Yue Wang,Xin-Xin Chen,Xing Zhou,Xiao-Yi Xu,Zhi-Qiang Li,Mei-Rong Zhang,Xiao-Hui Yao,Jun Wang,Wei-Guo Zhao,Dong-Yang Zhang,Tao Chen
Enzyme catalysis applications are limited because of their poor stability under extreme conditions. Using metal–organic frameworks (MOFs) as enzyme immobilization carriers efficiently solves this problem. However, MOFs easily agglomerate, are difficult to recover as a crystalline powder, and can only be used under continuous stirring, resulting in low reaction efficiencies. The use of immobilized enzymes for continuous fluid catalysis to improve catalytic efficiency remains challenging. At the same time, the spatial division of most immobilized enzyme porous materials is disordered, which leads to poor mass transfer efficiency and consequently low reaction rates. In this context, we want to construct a new type of reactor that solves the problem of enzyme stability by encapsulating enzymes in MOFs and then using low-cost and easily available silk fabric materials as immobilized carriers to load MOF immobilized enzymes. The ordered structure of silk fabric enhances substrate mass transfer, thereby improving the catalytic efficiency of the reactor. By comparing the mass transfer of a continuous fluid catalytic reactor with ordered silk fiber immobilized enzyme (OSCR) with that of a continuous fluid catalytic reactor with disordered silk fiber immobilized enzyme (DSCR) using crystal violet adsorption and catalytic process simulations, we demonstrated that the reaction efficiency in ordered spaces can be improved through mass transfer within each partition space. Finally, the reactor was used in the biotransformation of polydatin and demonstrated a high conversion of 98%, which was much higher than that of DSCR. This study revealed the enormous potential of ordered structure enzyme reactors in continuous fluid catalysis.
研究领域:
生物化学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
ADVANCED FUNCTIONAL MATERIALS
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2025
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IF 19
Qilong Zhao,Chao Huang,Xuemin Du
Protein-based bio-products such as vaccines, antibodies, enzymes, and plasma are crucial in public health and life sciences, yet their efficacy is frequently compromised by temperature fluctuations, especially repeated freeze-thaw cycles during storage and transport. While monitoring freeze-thaw damage is critical for the quality control of these bio-products, current methods lack the capability to indicate the exact number of freeze-thaw cycles. Here, structural color liquids enable visualized freeze-thaw monitoring (FT-SCLs) are introduced by harnessing their irreversible sol-gel phase transition under repeated freeze-thaw cycles, which are constructed by assembling periodically structured poly(styrene-acrylic acid) colloidal particles within a poly(vinyl alcohol) suspension. The FT-SCLs undergo irreversible sol-gel transition and therefore unidirectional alteration of their periodic structures during freeze-thaw cycling, imparting stepwise and unrecoverable color change (from red to green) to indicate the exact number of freeze-thaw cycles. Through modulating the sol-gel transition, the FT-SCLs are constructed with adjustable sensitivity across practically relevant temperature ranges (−80–−4 °C) and customizable response thresholds for diverse application scenarios. Leveraging their unique capabilities of freeze-thaw monitoring via non-tampered optical signals, such FT-SCLs exhibit broad applicability in vaccine storage, whole blood preservation, and enzyme stability monitoring, which can further be extended for cell cryopreservation and the food industry.
研究领域:
生物技术
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材料科学
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公共健康
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Polymer Materials
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2024
·
IF 4.4
Cairong Qiao,Ling Qian,Qiang Peng,Wanqing Yue
We constructed heteropolysaccharide-based complex coacervate microdroplets using pectin and DEAE-dextran via electrostatic interactions. The coacervate microdroplets were stable from pH 3 to 12 and completely dissociated at a NaCl concentration of 160 mM. When cholesterol oxidase was distributed in the microdroplets, the enzyme activity of cholesterol oxidase did not decrease, and it was made more stable. Through spiked recovery experiments of cholesterol in serum and a comparison with the results of commercial assay kits, we successfully validated that the assay can be used for the detection of cholesterol in real samples.
研究领域:
生物化学
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分析化学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF BIOTECHNOLOGY
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2019
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IF 3.163
Yuxiao Feng,Le Zhong,Ying hou,Shiru Jia,Jiandong Cui
Zeolitic imidazole frameworks (ZIFs) with tunable pore sizes and high surface areas have recently used as an effective support for immobilizing enzymes. However, the instability in the aqueous acidic environment has limited their practical applications in some cases. In this work, we develop a novel catalase/ZIFs composite with mesoporous silica shell (mSiO 2 @CAT/ZIFs) via co-precipitation, and controlled self-assembly of silanes. During preparation, the cetyltrimethylammonium bromide induced the formation of the mesostructured silica layer on the outer surface of CAT/ZIFs. The resultant mSiO 2 @CAT/ZIFs exhibited high activity recovery (92%). Compared with the conventional CAT/ZIFs and free CAT, mSiO 2 @CAT/ZIFs exhibited excellent acid resistance. For example, after 30 min in acetate buffer solution (pH 3.0), the CAT/ZIFs and free CAT almost lost activity whereas the mSiO 2 @CAT/ZIFs still retained 35% of original activity. Meanwhile, the thermostability of the mSiO 2 @CAT/ZIFs was enhanced significantly compared with conventional CAT/ZIFs. In addition, the mSiO 2 @CAT/ZIFs displayed excellent storage stability, and retained 60% of its initial activity after 15 days storage period. Furthermore, the mSiO 2 @CAT/ZIFs could maintain 70% of its initial activity after 8 continuous uses, demonstrating superior reusability than the free CAT and CAT/ZIFs. These results demonstrated that the mSiO 2 @CAT/ZIFs are potential for practical applications even in the acidic environment.
研究领域:
生物化学
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材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
RSC Advances
·
2014
·Vol. 4
·期 52
·27422-27429
·
IF 3.708
Chen Chen,Haogang Duan,Chunmei Gao,Mingzhu Liu,Xin'an Wu,Yuhui Wei,Xinyu Zhang,Zhen Liu
Cardiovascular disease (CVD) has become the leading cause of death globally. Nattokinase (NK), as a novel thrombolytic agent, has gained more and more attention. However, NK is susceptible to chemical oxidation, and subsequent inactivation denaturation. Modification of an enzyme to improve its stability usually brings about falling enzymatic activity. In this study, folic acid modified chitosan (CS-FA) was synthesized, and a series of NK/CS-FA complexes with different mass ratios were prepared. In vitro thrombolysis experiments indicated that NK/CS-FA showed obvious advantages in its fibrinolysis activity and stability. With the NK : CS-FA mass ratio of 100 : 1 (molar ratio of NK : chitosan pyranose ring = 3 : 5), NK/CS-FA 100 : 1 exhibited the best fibrinolysis activity and the thrombi dissolved completely within 17 hours at a constant rate, while the un-modified NK dissolved only 35 wt% of the thrombus in the same duration. NK/CS-FA 100 : 1 retained more than 53% enzymatic activity at 80 °C or pH 2, as a comparison, only 17% enzymatic activity was left for un-modified NK under the same conditions.
研究领域:
生物化学
·
医学
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
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2021
·
IF 6.953
Yang Zhou,Ya-Jiao Wu,Lei Wang,Juan Han,Jia-Cong Wu,Chun-Mei Li,Yun Wang
Easy deactivation of free enzymes under non-native condition has become a stumbling block to the industrial application of biocatalysis. Natural deep eutectic solvent (NADES) has been exploited as a novel reaction medium for improving enzyme stability. The present work focused on preserving and enhancing the activity of carbonic anhydrase (CA) in a more economical and biocompatible NADES system. We synthesized six choline chloride/betaine-based NADES and analyzed the effects of compositions and concentrations of NADES on their physicochemical properties. The Bet-Gly (1: 2) NADES (55%) was proved to be more suitable as reaction medium for CA by analyzing enzyme activity in the presence of NADES. The enhancement in the stability of CA was found to be as a result of a three-dimensional hydrogen bonding network, rather than the individual or the synergistic effect of betaine and glyceride. The conformational change of CA to become more compact was confirmed both by fluorescence spectrum analysis and circular dichroism analysis. It is worth mentioning that a remarkable thermal stability was maintained when CA was incubated at temperature below 60 °C, and about 96% of activity was still restored in 55% NADES at 60 °C for 12 h.
研究领域:
生物化学
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酶工程
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绿色化学
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产品关联
DOI
PubMed
高影响因子
Green Synthesis and Catalysis
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2021
·
IF 0
Baoxing Shen,Rui Ding,Jianan Dai,Yuan Ji,Qingzhuo Wang,Yuwen Wang,He Huang,Xing Zhang
Traditional chemical methods for nitro reduction are typically conducted under harsh conditions and are readily explosive, such as hydrogen pressurization and zinc powder reduction. Nitroreductase (NTR) as a biocatalyst may represent a promising strategy to solve this synthetic challenging. Unfortunately, due to the availability of this enzyme, the lack of long-term stability as well as challenging recovery process, very limited work was reported about its applicability for the reduction of nitro groups. Here, based on the highly efficient expression of NTR in our lab, we firstly reported the encapsulation of NTR into ZIF-8 to form [email protected] The resulting framework composite demonstrated an excellent protective capability of enzyme against harsh environment and could also simplify the complex downstream separation and recovery operations. Moreover, after five successive cycles of reuse to reduce 4-NP, the residual [email protected] still reserved a certain activity, which can significantly reduce the processing cost and might be applicable in the industries in the future.
研究领域:
化学工程
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生物技术
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催化
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材料科学
✓ 已验证
DOI
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
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2015
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IF 2.587
Xiujuan Li,Chuan Zhang,Shuang Li,He Huang,Yi Hu
Candida rugosa lipase was chemically modified with various polyethylene glycol functional ionic liquids to increase its catalytic performance. All tested polyethylene glycol functional ionic liquids improved lipase catalytic activity, thermostability, organic solvent tolerance, and adaptability to temperature and pH changes in olive oil hydrolysis reaction. In particular, lipase modified by [HOOCEPEG350Im][H2PO4] increased the catalytic activity by 1.7-fold, thermostability by 5.0-fold at 50 °C for 2.5 h, organic solvent tolerance by 13.3-fold in 60% dimethyl sulfoxide and 3.4-fold in 5% methanol compared with the native lipase. Investigations by ultraviolet, fluorescence, and circular dichroism spectroscopy revealed microenvironment changes, the increase in β-sheet and the decrease in α-helix content of secondary structures in the modified lipases. These changes were correlated with enzymatic properties alteration, including improved activity and stability of modified lipases. Compared with the results of previous reports, the novel modification with polyethylene glycol functional ionic liquids was more effective in improving the catalytic performance of lipase.
研究领域:
生物化学
·
酶工程
✓ 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）