Journal of Hazardous Materials Advances
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2021
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IF 0
Luo Li,Yi Li,Chunhu Tan,Tingting Zhang,Xiaoli Xin,Weihua Li,Jiansheng Li,Rui Lu
The mechanism of GO/rGO interaction with trypsin is investigated using multiple methods. UV-Vis reveals that trypsin has a maximum absorption at 278 nm, the absorption intensity increased demonstrating GO/rGO alters the solvent environment of trypsin and exposes the aromatic chromogenic groups. ITC experiments with GO and trypsin provide a negative ΔH of -25.98 KJ mol −1 and the association constant Ka of 4.829 × 10 −4 . The negative ΔS of -23.64 J mol −1 ∙K −1 is further given by the Gibbs–Helmholtz equation. Combining with the ζ potential result, the driving forces for binding include hydrogen bonding, electrostatic interaction forces and van der Waals forces. Fluorescence spectroscopy shows that GO/rGO can significantly quench the fluorescence intensities of trypsin. The equilibrium constant Kd of GO/ rGO-24h / rGO-48h is 4.41±0.07, 5.82±0.53, 7.24±0.25, respectively, which means the reduced content of oxygen-containing groups can weaken the binding forces between GO/rGO and trypsin. CD show that even low concentrations of GO/rGO affect the secondary structure of trypsin, mainly decreasing the α -helix and β -fold content while increasing the β -turn and random coil content of trypsin. Overall, GO/rGO can effectively interact with trypsin, the oxidation degree of GO/rGO can affects the combination of trypsin and further influence on protein conformation and function.
研究领域:
生物化学
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分子生物学
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蛋白质科学
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DOI
ANALYTICA CHIMICA ACTA
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2019
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IF 5.256
Liubing Kong,Ying Gan,Tao Liang,Longjie Zhong,Yuxiang Pan,Dmitry Kirsanov,Andrey Legin,Hao Wan,Ping Wang
As a powerful tool for medical diagnosis and bioanalysis , conventional optical spectrometers are generally expensive, bulky and always require an accompanying data processing device. In this work, we developed a novel smartphone-based CD-spectrometer (SCDS) for high sensitive and ultra-portable colorimetric analysis , with the advantage of cost-effective and simplicity. The distance between the light source and slit, the structure of SCDS and the parameters of camera in the smartphone were all optimized to ensure the best analytical performance. Besides, the SCDS employed HSV color model and utilized the overall intensity calculated by summing V-value of adjacent position for the absorbance measurement. In this way the errors caused by the low resolution of CD-grating can effectively be eliminated to promote the sensitivity of the SCDS. The performance of the SCDS was first validated for colorimetric detection of BSA with a detection limit of 0.0073 mg/mL, which is superior compared to that of the microtiter plate reader (MTPR). Moreover, by combining with 3,3′,5,5′-tetramethylbenzidine-manganese dioxide (TMB-MnO 2 ) nanosheets reaction, a high sensitive and specific system for ascorbic acid detection was established. The SCDS gives a detection range from 0.6250 μM to 40 μM with a detection limit of 0.4946 μM for AA detection. Compared to other studies, the SCDS features wide detection range and very low detection limit with low cost instrument. Therefore, the SCDS will be an ideal and promising colorimetric system for point-of-care (POC) application in food security, disease diagnosis and environmental monitoring.
研究领域:
医学诊断
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生物分析
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分析化学
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即时检测
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环境监测
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食品安全
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产品关联
DOI
PubMed
高影响因子
Innovative Food Science & Emerging Technologies
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2019
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IF 4.085
Ming Dong,Yujuan Xu,Yumei Zhang,Minyi Han,Peng Wang,Xinglian Xu,Guanghong Zhou
The present study was performed to clarify the effects of pulsed electric field (PEF) on the physicochemical properties and conformations of myofibrillar proteins (MPs) extracted from pale, soft, exudative (PSE)-like chicken breast meat. Various PEF parameters, including the electric field intensity (0–28 kV/cm) and pulse frequency (0–1000 Hz), were varied. The results showed that as the PEF intensity increased, the solubility, surface hydrophobicity and sulfhydryl group content of the MPs were significantly improved. However, when the intensity exceeded 18 kV/cm, these properties declined, which was possibly due to protein aggregation caused by functional group interactions. Additionally, the PEF treatment altered the rheological properties of PSE-like MPs and induced the formation of low-elasticity MPs. However, sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) demonstrated that the primary structure of the MPs was not altered after the PEF treatment. According to the circular dichroism (CD) spectroscopy results, the α-helix contents of the PEF-treated samples were increased but the β-turn and random coil contents were reduced. Industrial relevance The occurrence of PSE-like chicken meat is one of the most serious quality issues worldwide and can decrease the consumer's purchasing desire and result in extensive economic losses for the poultry processing industry. MPs play a vital role in the qualitative characteristics of chicken products. As a potential novel processing technology, PEF has potential applications for improving the functionality of PSE-like chicken protein to expand its application in the food industry.
研究领域:
食品科学
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蛋白质化学
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肉类加工
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产品关联
DOI
高影响因子
JOURNAL OF COORDINATION CHEMISTRY
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2019
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IF 1.685
Xuexue Xu,Shuang Wang,Yaxuan Mi,Huaqian Zhao,Zebao Zheng,Xiaolong Zhao
A polypyridyl ruthenium(II) complex with hydroxyquinoline-derived ligand has been synthesized and characterized. The ability to act as telomeric quadruplex inducer and stabilizer, and quadruplex-binding properties of the complex have been evaluated by absorption and emission analyses, fluorescent intercalator displacement (FID) titrations, circular dichroism (CD) spectroscopy, polymerase chain reaction (PCR) stop assay, color reaction studies, fluorescence resonance energy transfer (FRET) melting assay, Job plot, and molecular modeling. Observations revealed that the complex could well induce and stabilize the formation of antiparallel G-quadruplex of telomeric DNA in the presence or absence of metal cations, and showed superior G-quadruplex selectivity over duplex DNA with remarkable ΔTm value of 18.0 °C even at 50-fold excessive supplies of calf thymus (ct) DNA. The complex exhibited high interaction affinity of 2.56 × 106 M−1 with G-quadruplex DNA and evident luminescence enhancements of 3.1 and 4.2 times for quadruplex binding in Na+ and K+ buffer, respectively. In addition, the 1:1 [quadruplex]/[complex] binding mode ratio was determined. The results suggest that the complex can be developed as potential anticancer reagent through binding and stabilization of G-quadruplex DNA.
研究领域:
化学
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生物化学
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分子生物学
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癌症研究
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产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）