INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
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2024
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IF 7.7
Fan Yang,Hui-Hui Xie,Fan Du,Xiaomin Hou,Si-Fu Tang
Enzyme immobilization is an effective strategy for achieving efficient and sustainable enzyme catalysis. As a kind of promising enzyme-loading materials, the systematic research on zirconium based metal organic frameworks (Zr-MOFs) about immobilization performance at molecular level is still in its initial stage. In this work, UiO-66 was functionalized with various groups (-H, -NH 2 , -COOH, -OH, -2OH) for the immobilization of cytochrome c (Cyt c) and antioxidant enzyme catalase (CAT). Then the effects of surface-functionalized UiO-66 derivatives on the loading efficiency, enzyme stability and catalysis kinetics were systematically investigated. In addition, the affinity constants of Cyt c and CAT towards UiO-66-series MOFs carriers were also compared. The results have shown that hydroxyl group functionalized UiO-66 represents the highest enzyme loading capacity, enhanced activity and improved stability for Cyt c and CAT possibly due to high surface area and suitable microenvironments as well as enhanced affinity towards the enzymes provided by the introduction of a single hydroxyl group. Our research would foresee immense potential of MOFs in engineering biocatalysts.
研究领域:
材料科学
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生物催化
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化学工程
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生物化学
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF IMMUNOLOGICAL METHODS
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2024
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IF 1.6
Fang Lu,Xiqun Wu,Fa Zhang,Jiaqiang Wu,Zhaodong Yuan,Baomin Wang,Guiyu Tan,Suqin Guo
Immunoassay relies on antibodies, but traditional antibodies such as monoclonal antibody (mAb) require animal immunization and complex procedures. Single-chain variable fragment (scFv) becomes a potential alternative to mAb with advantages of the low cost, rapid and easy prepared. In the present study, we prepared scFvs against dihydroartemisinin (DHA) based on E. coli and HEK293T cell expression system, named MBP-scFv and scFv-Fc, respectively. Their properties were compared with the parent mAb. The calculated affinity constants of mAb, MBP-scFv and scFv-Fc were 2.1 × 10 8 L mol −1 , 2.2 × 10 7 L mol −1 and 1.6 × 10 8 L mol −1 , respectively. The half inhibitory concentration (IC 50 ) of mAb, MBP-scFv and scFv-Fc were 1.16 ng mL −1 , 2.15 ng mL −1 and 6.57 ng mL −1 , respectively. Both the scFv showed less sensitive than the mAb based on the IC 50 . The cross-reactivities of MBP-scFv for artemisinin and artesunate exhibited similarities to the mAb, yet the cross-reactivities of scFv-Fc for these compounds exceeded those of the mAb significantly. The stability of the scFvs was ascertained to be maintained for over 5 days at room temperature, and for more than a month at both 4 °C and − 20 °C. After that, the indirect competitive enzyme-linked immunosorbent assays (icELISAs) based on the scFv from E. coli were used to detect the DHA content in eight drug samples, and the result was consistent with ultra-performance liquid chromatography simultaneously. Although scFv can be used for quantitative determination of drugs, but it still cannot completely replace mAb in immunoassay without evolution and modification.
研究领域:
免疫学
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药学
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分子生物学
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产品关联
DOI
PubMed
高影响因子
Journal of Materials Chemistry B
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2013
·Vol. 2
·期 11
·1530-1538
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IF 0
Zhihong Zhang,Shunli Liu,Yu Shi,Yuanchang Zhang,Dave Peacock,Fufeng Yan,Peiyuan Wang,Linghao He,Xiaozhong Feng,Shaoming Fang
A label-free and effective aptasensor based on an amino-functionalized nanocomposite of graphene and plasma-polymerized allylamine (G–PPAA) was developed for thrombin detection. Graphene was assembled on the substrate, followed by the self-assembly of octadecylamine (OTA) to protect the graphene from etching by subsequent plasma irradiation. Afterward, PPAA was deposited onto the graphene surface with the self-assembled OTA, and the nanocomposite with amino groups was fabricated. The label-free thrombin aptamer was immobilized onto the amino-functionalized nanocomposite matrix via electrostatic interaction between the phosphate groups of the aptamer and the amino groups in PPAA. The process was investigated using impedimetric detection and a quartz crystal microbalance (QCM). The chemical compositions, surface morphology, and electrochemical properties were found to be dependent on the plasma conditions used in the polymer deposition. The amounts and kinetics of aptamer immobilization and thrombin detection were determined using QCM measurements. A relatively high affinity constant of aptamer immobilization and low detection limit for thrombin were achieved by using the G–PPAA film as the biosensor matrix. Results suggest that G–PPAA films can be applied in gene therapy and protein detection.
研究领域:
生物传感器
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纳米技术
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分析化学
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生物医学工程
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产品关联
DOI
PubMed
SENSORS AND ACTUATORS B-CHEMICAL
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2021
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IF 7.46
Kai-Xin Song,Dong Chen,Zi-Yang Liao,Xuan Yu,Fei-Fei Guo,Ri-Lei Yu,Meng-Zhen Xu,Ya-Mu Xia,Wei-Wei Gao
In this work, an efficient electrochemical biosensor for the detection of DNA damage induced by the interaction of a novel antitumor agent AD-NU was investigated by CV , DPV and SWV methods. The GCE was modified with calf thymus DNA, G-quadruplexes, poly dA and poly dG, respectively. Among all the candidates, compound AD-NU was the optimum ligand because of the minimum energy when binding to DNA or TOP II by molecular docking. The electrochemical analysis revealed the redox mechanism of AD-NU on the GCE surface, which included two consecutive reversible processes of 9,10-diquinone and irreversible redox of nitroso group . The DNA damage caused by AD-NU was investigated by comparing the intensity changes of dGuo and dAdo oxidation peaks in DNA strands, and monitoring the appearance of peak for oxidative product 8-oxoGua. Further confirmation for the interaction between AD-NU and DNA was performed by UV–vis absorption and fluorescence titration, which implied the intercalation of AD-NU into DNA base pairs with a high affinity constant ( K b = 13.7 ×10 5 M −1 ). The electrophoresis also revealed the potency of AD-NU to cleave and unwind DNA strands. Finally, AD-NU was proved to have good antiproliferative activity toward tumor cells, with IC 50 values of 3.0 μmol ∙ L −1 for A549 cell lines and 3.3 μmol ∙ L −1 for Hela cell lines, superior to MTZ reference.
研究领域:
电化学
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生物传感器
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分子生物学
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癌症研究
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分析化学
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药理学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）