MICROCHEMICAL JOURNAL
·
2024
·
IF 4.9
Rikun Cui,Linna Li,Lili Liu,Zhen Li,Zhenzhao Wang,Xingtong Liu,Lei Tian,Fujun Yao,Xiaofeng Kang,Yanli Guo
Nucleic acid aptamers, which are short single-stranded RNA or DNA molecules, undergo conformational changes upon recognizing small molecules. However, their structural characterization is challenging due to the flexibility of single-stranded oligonucleotides. Nanopores provide a sensitive method for single-molecule analysis of molecular conformational changes as they transport through the pore. In this study, we employed α-hemolysin (α-HL) nanopore with high spatiotemporal resolution to investigate the conformational changes of DNA aptamer (ADO-23) upon binding to adenosine (Ado) molecules. Unlike the events generated by the aptamer alone, the DNA-Ado complex produced two distinct new characteristic events, indicating the formation of two unique secondary structures. By analyzing current events, the structures formed by the DNA-Ado complex were speculated to be hairpin DNA and G-quadruplex (G4) DNA. Furthermore, we demonstrated the potential of the aptamer as a chiral selector within the nanopore. The results showed that the aptamer specifically bound to D-Ado and not to L-Ado. Finally, we realized specific and sensitive detection of small molecule Ado by α-HL pore, with a detection limit as low as 10.5 nM, and successfully applied it to the detection of real human serum samples. The nanopore platform provides a powerful tool for studying small molecule-biomolecule conformational changes, and we constructed sensors for detecting adenosine through the aptamer. This work also offers a promising new approach to the recognition of enantiomers at the single-molecule level.
研究领域:
生物物理学
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分子生物学
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纳米技术
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产品关联
DOI
高影响因子
FOOD AND CHEMICAL TOXICOLOGY
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2012
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IF 2.999
Ying Liu,Rutao Liu
Great attention is devoted to persistent organic pollutant (POP), among which the pesticide dicofol is critical related to food safety and might raise the risk of cancer incidence. To take a comprehensive evaluation of its toxicity, we investigated its interaction with a serine protease α-chymotrypsin by multi-spectroscopic techniques and molecular modeling method. UV–vis absorption, synchronous fluorescence, and circular dichroism data elucidated that dicofol unfolded the framework of α-chymotrypsin and led to secondary structure changes. The fluorescence and lifetime assay determined the static quenching mode and binding parameters. As an auxiliary method, molecular modeling has displayed the specific binding site and information about binding forces and drug-residues distances which were consistent with conclusions from above. Additional, enzyme activity assay gave evidence at the functional aspect to clarify the fact that dicofol could contribute to the conformational changes and furthermore alter the function of the enzyme.
研究领域:
生物化学
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环境毒理学
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食品安全
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DOI
PubMed
高影响因子
Nature Communications
·
2024
·Vol. 15
·期 1
·1-10
·
IF 14.7
Wang Tianjiao,Xin Yu,Chen Bingfeng,Zhang Bin,Luan Sen,Dong Minghua,Wu Yuxuan,Cheng Xiaomeng,Liu Ye,Liu Huizhen,Han Buxing
Achieving selective hydrodeoxygenation of α, β-unsaturated carbonyl groups to alkenes poses a substantial challenge due to the presence of multiple functional groups. In this study, we develop a ZnNC-X catalyst (X represents the calcination temperature) that incorporates both Lewis acidic-basic sites and Zn-N x sites to address this challenge. Among the catalyst variants, ZnNC-900 catalyst exhibits impressive selectivity for alkenes in the hydrodeoxygenation of α, β-unsaturated carbonyl compounds, achieving up to 94.8% selectivity. Through comprehensive mechanism investigations and catalyst characterization, we identify the Lewis acidic-basic sites as responsible for the selective hydrogenation of C=O bonds, while the Zn-N x sites facilitate the subsequent selective hydrodeoxygenation step. Furthermore, ZnNC-900 catalyst displays broad applicability across a diverse range of unsaturated carbonyl compounds. These findings not only offer valuable insights into the design of effective catalysts for controlling alkene selectivity but also extend the scope of sustainable transformations in synthetic chemistry.
研究领域:
催化
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有机化学
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可持续化学
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产品关联
DOI
PubMed
高影响因子
ADVANCED POWDER TECHNOLOGY
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2024
·
IF 4.2
Zunlan Hu,Fangnan Zhao,Zhipeng Xie
A facile procedure was provided to obtain amorphous Si 3 N 4 powder via a liquid-phase method, followed by a heat treatment process to realize tailorable shapes for α-Si 3 N 4 crystal, while Si 3 N 4 granules were synthesized and whiskers were inhibited. The influence of the temperature on the particle morphology and growth mechanisms were investigated. Characterizations indicated that the crystallization temperature played an important role in controlling the morphology of α-Si 3 N 4 powder, while the relatively lowly temperature (below 1519 °C) was beneficial to forming whiskers. The growth of Si 3 N 4 whiskers, derive from the reaction between SiO(g) and N 2 , follows the vapor–solid (VS) mechanism, which is inhibited by the increase in temperature. Instead, higher temperatures were conducive to forming granular structures. Highly crystalline α-Si 3 N 4 granules were prepared at 1550 °C due to Si*(g) and N*(g) recombining to Si 3 N 4 nuclei via the vapor–solid-solid (VSS) mechanism providing a theoretical basis for inhibiting the production of the whiskers.
研究领域:
材料科学
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化学工程
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产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2017
·
IF 6.216
Jing Deng,Yongjian Ge,Chaoqun Tan,Hongyu Wang,Qingsong Li,Shiqing Zhou,Kejia Zhang
Nanoscale α-MnO 2 with different morphologies (nanoparticles, nanoflowers and nanorods) were synthesized via a facile hydrothermal method and tested in peroxymonosulfate (PMS) activation for ciprofloxacin (CIP) degradation. The catalytic activity of α-MnO 2 mainly relied on the specific surface area and crystallinity, and followed the order of α-MnO 2 nanoflowers > α-MnO 2 nanorods > α-MnO 2 nanoparticles > commercial MnO 2 . Acidic condition was more beneficial to CIP removal than neutral condition, and the degradation would be greatly accelerated in alkaline circumstance. The introduction of chloride and bicarbonate displayed concentration-dependent dual effect. The presence of natural organic matter (NOM) exerted the detrimental effect on CIP degradation. Eleven oxidation products were identified by UPLC–MS/MS and the changes of their concentrations were monitored, five products showed monotonous uptrend while four intermediates present monotonous downtrend once they were generated. Piperazine ring cleavage, hydroxylation and F/OH substitution were found to be the important oxidation pathways. The acute toxicity of resulted solution gradually decreased with the lapse of time, and higher PMS concentration favored the detoxification. The CIP removal in α-MnO 2 /PMS process was also efficient under the actual water background, which was testified by the results of fluorescence excitation-emission matrix (EEM).
研究领域:
环境科学
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化学
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DOI
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2024
·
IF 7.7
Guangjin Yu,Jing Wang,Qingshan Xiong,Yunqi Xu,Shouhu Xuan,Ken Cham-Fai Leung,Qunling Fang
With the prevalence of drug-resistant bacteria and the waning effects of antibiotics, nanoplatform has become an effective strategy for fighting infections. This work reports a dipolar-hollowed α-Fe 2 O 3 @Au/Polydopamine (PDA) nanospindle which possesses both photothermal-photodynamic (PTT-PDT) coupling antibacterial and drug carrying performance. Firstly, the spindle type α-Fe 2 O 3 @Au/PDA particle was prepared by a simple one-step strategy and then the dipolar-hollow structure was obtained by controlling etching the inside α-Fe 2 O 3 core with hydrochloric acid. After further loading the photosensitizer zinc phthalocyanine (ZnPc), the dipolar-hollowed α-Fe 2 O 3 @Au/PDA-ZnPc nanospindles were obtained. Owing to the dipolar-hollowed interior, the nanospindles are also effective in carrying antitumor drug doxorubicin (DOX) and shows a good drug loading-release behavior. The dipolar-hollowed α-Fe 2 O 3 @Au/PDA nanospindles exhibits a high antibacterial performance against Escherichia coli ( E. coli ) and Staphylococcus aureus ( S. aureus ) under near-infrared (NIR) and Xenon lamp irradiation. When α-Fe 2 O 3 @Au/PDA-ZnPc nanospindles concentration was increased to 100 μg/mL, the antibacterial rate was close to 100 %. In comparison to the original α-Fe 2 O 3 @Au/PDA nanospindles, the product achieved a lower effective antibacterial temperature. This triple-mode therapy (PTT/PDT/Drug) provides an interesting design idea for anisotropic therapeutic nanoplatform which can be applied in low-temperature antibacterial and drug delivery.
研究领域:
纳米医学
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生物材料学
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抗菌研究
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产品关联
DOI
PubMed
高影响因子
TETRAHEDRON
·
2017
·
IF 2.651
Wei Wu,Yingcai Ding,Ping Xie,Qiujie Tang,Charles U. Pittman,Aihua Zhou
Structure containing the C S bond exist widely in nature, drugs and chemical materials . Here, a novel sulfenylation protocol employing an aryl or alkyl halide and odorless and cheap S as reagents was developed, generating regioselective alkyl-S- and Ar-S-substituted imidazol[1,2-α]pyridine derivatives in good yields under relatively environmentally friendly and mild conditions. This protocol enriches current thioether-producing methods, making up for the shortcomings of previous sulfenylation methods which can only make MeS- and ArS-substituted imidazol[1,2-α]pyridine derivatives.
研究领域:
有机化学
·
药物化学
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DOI
高影响因子
FOOD CHEMISTRY
·
2025
·
IF 9.8
Tao Chen,Changdong Lin,Weihang Lu,Shuo Wang,Cheng Shen,Juyuan Luo,Yulin Li
In the present study, six 7- O -glycosyl acylation of flavonoids derived from lutonarin and saponarin were obtained from barley seedlings by medium-pressure LC, high-speed counter-current chromatography and preparative HPLC guided by UPLC-QTOF-MS/MS. Their inhibitory effects on α-glucosidase were investigated. Structure–activity relationship showed 7- O -glycosyl acylation enhanced inhibitory effect on α-glucosidase with coumaroyl > feruloyl > hydroxybenzoyl > sinapoyl. The IC₅₀ values for saponarin and its four acylated products were 802.4 ± 0.48 μg/mL, 374.6 ± 0.16 μg/mL, 461.6 ± 0.27 μg/mL, 523.8 ± 0.24 μg/mL and 585.8 ± 0.42 μg/mL, respectively. Steady-state fluorescence spectroscopy revealed 7- O -glycosyl acylation enhanced the fluorescence quenching rate of α-glucosidase. Molecular docking revealed 7- O -glycosyl acylation formed more hydrogen bonds and hydrophobic interactions with α-glucosidase. Synchronous fluorescence spectroscopy showed all compounds altered the hydrophobic microenvironment surrounding the tryptophan residues in α-glucosidase. Circular dichroism spectroscopy indicated 7- O -glycosyl acylation modified the conformation and secondary structure of α-glucosidase.
研究领域:
植物化学
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药理学
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产品关联
DOI
PubMed
高影响因子
CHINESE JOURNAL OF CATALYSIS
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2024
·
IF 15.7
Changpo Ma,Ying Lai,Tiange Zhao,Xiaoxuan Zhang,Haichao Liu,Weiran Yang
α,ω-Dicarboxylic acids are important intermediates for the preparation of polyamides , polyesters and polyurethanes . However, their production pathways are limited and usually suffer from low efficiency and environmental problems. Here, we report an innovative approach to synthesize C+2 dicarboxylic acids directly from cyclic ethers by dicarbonylation. Different from the general findings that C+1 monocarboxylic acids are produced by carbonylation of cyclic ethers involving alkene intermediates, in this work, by manipulating the reaction system with RhCl 3 and iodine in acetic acid, diiodide-substituted intermediates were selectively formed and subsequently converted to dicarboxylic acids in the presence of H 2 and CO. As high as 84% yield of adipic acid was obtained directly from tetrahydrofuran. This catalytic system is applicable not only to a wide variety of cyclic ethers but also to different primary diols to synthesize C2-elongated α,ω-dicarboxylic acids. This work provides a novel dicarbonylation strategy for the efficient synthesis of adipic acid, glutaric acid and other important α,ω-dicarboxylic acids (such as 1,7-heptanedioic acid and 1,8-octanedioic acid) that are still not easily synthesized by other methods.
研究领域:
有机化学
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催化
·
材料科学
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产品关联
DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2020
·
IF 3.99
Bao-Shui Wu,Peng Wang,Shu-Hua Teng
Mesoporous carbon-coated iron oxide (α-Fe 2 O 3 @C) nanoparticles were hydrothermally synthesized by using α-Fe 2 O 3 nanospheres (ca. 50 nm) as the cores and resorcinol as the carbon source of the shells. The formation of the mesoporous carbon coatings was confirmed by means of SEM, TEM , FT-IR, TG, XPS and BET measurements. Moreover, the coating thickness was easily adjusted to be 4, 7 and 10 nm by changing the amount of resorcinol. When used as the anodes for lithium-ion batteries (LIBs), the α-Fe 2 O 3 @C nanoparticles exhibited significantly improved electrochemical properties as compared to pure α-Fe 2 O 3 nanoparticles. With the increase of the coating thickness, the α-Fe 2 O 3 @C electrodes presented an initial increase and subsequent decrease in their cycling stability and rate performance. Especially, the α-Fe 2 O 3 @C-7 nanoparticles displayed a high reversible capacity of 1223 mA h/g at 1 A/g, a good cycling stability retaining 1093 mA h/g at 1 A/g after 100 cycles as well as a remarkable rate performance of 570 mA h/g at 5 A/g. The quantitative kinetic analysis revealed that 58 % of the charge storage was contributed by the capacitive process at 0.5 mV/s. The well-defined core-shell structure and superior electrochemical performance of the α-Fe 2 O 3 @C-7 nanoparticles will make them a promising anode for LIBs.
研究领域:
材料科学
·
电化学
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DOI
高影响因子
ANALYTICAL AND BIOANALYTICAL CHEMISTRY
·
2023
·Vol. 415
·期 9
·1733-1740
·
IF 4.3
Tang Kexin,Dong Jiacheng,Zheng Zhengheng,Zhang Ting,Pan Huayi,Jia Honghua,Li Yan,Wei Ping
ω-Transaminases (ω-TAs) are widely available for the production of chiral amines and unnatural amino acids. Herein, a rapid spectrophotometric method was developed for screening ω-TAs based on the colored products that can be generated from transamination reactions between aliphatic α-diketones and amino donors catalyzed by ω-TAs. The possible mechanism of the formation of the colored product was investigated according to LC-Q-TOF–MS analysis. Among seven diketones, 2,3-butanedione was selected as the most suitable amino acceptor for colorimetric screening of ω-TAs with high efficiency, high sensitivity, and low background interference. Meanwhile, the absorbance of the colored product generated by 2,3-butanedione catalyzed by ω-TAs in this method was linearly correlated with the results by HPLC analysis. This method was also confirmed to effectively screen ω-TA mutants with high activity towards isopropylamine. Graphical Abstract
研究领域:
生物化学
·
酶工程
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DOI
PubMed
高影响因子
MOLECULAR PHARMACEUTICS
·
2018
·
IF 4.556
Chu Tang,Yang Du,Qian Liang,Zhen Cheng,Jie Tian
The ability to detect breast cancer early in its progression is essential to improve patient survival and quality of life. The noninvasive and dynamic imaging and functional assessments of estrogen receptor-alpha (ERα), which is commonly expressed at high levels in breast cancer, are important for effective diagnosis and treatment. Hence, the development of a specific ERα-targeted probe is a major research goal. To that end, in the present study, we created a novel near-infrared (NIR) fluorescent probe, IRDye800CW–E2, for targeted ERα imaging in breast-tumor-bearing mice. IRDye800CW–E2 consisted of a cyanine dye IRDye800CW as the NIR fluorophore and the E2 analogue ethinyl estradiol amine as an ERα targeting ligand. The ethinyl estradiol amine was initially labeled with fluorescein isothiocyanate (FITC) to evaluate the binding specificity to human breast-tumor cells in vitro. Flow chamber and in vitro confocal laser endomicroscopy imaging experiments demonstrated that FITC–E2 was specifically taken up by MCF-7 cells. Furthermore, NIR fluorescence imaging revealed the ability of IRDye800CW–E2 to rapidly target tumors and to achieve good contrast between tumors and background signal 4–48 h postinjection. The fluorescent signal of IRDye800CW–E2 in tumors was successfully blocked by the coinjection of the endogenous ERα-ligand 17β-estradiol (E2) and the probe. Ex vivo fluorescent imaging further confirmed high uptake of the probe by tumors. These results indicated that IRDye800CW–E2 has great potential as an ERα-targeted imaging probe for early breast-tumor detection and has potential for clinical translation.
研究领域:
医学影像学
·
肿瘤学
·
分子生物学
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DOI
PubMed
高影响因子
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