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1.
Cell membrane chromatography is an effective method for screening bioactive components acting on specific receptors in complex systems, which maintains the biological activity of the membrane receptors and improves screening efficiency. However, traditional cell membrane chromatography suffers from poor stability, resulting in a limited life span and low reproducibility, greatly limiting the application of this method. To address this problem, cyanuric chloride-decorated silica gel was used for the covalent immobilization of the cell membranes. Cyanuric chloride reacts with amino groups on the cell membranes and membrane receptors to form covalent bonds. In this way, the cell membranes are not easy to fall off. The column life of the cyanuric chloride-decorated epidermal growth factor receptor/cell membrane chromatography column was extended to more than 8 days, whereas the column life of the normal cell membrane chromatography column dropped sharply in the first 3 days. A cyanuric chloride-decorated epidermal growth factor receptor/cell membrane chromatography online HPLC-IT-TOF-MSn system was applied for screening drug leads from Trifolium pratense L. One potential drug lead, formononetin, which acts on the epidermal growth factor receptor, was screened. Our strategy of covalently immobilizing cell membrane receptors also improved the stability of cell membrane chromatography.  相似文献   
2.
近年来,设计和合成高性能非富勒烯受体(NFAs)材料已经成为太阳能电池研究领域的前沿课题。基于DA'D型稠环结构的NFAs由于具有吸光系数高、能级和带隙可调、结构易于修饰、分子可高效合成、光电学性能优异等优点而受到了越来越广泛的关注。在短短7年的时间里,能量转换效率(PCE)从3%~4%提高到18%。2019年初邹应萍等报道了一个优秀的受体分子Y6,与PM6共混制备单结电池,获得了15.7%的能量转换效率。Y6类受体材料的中心给电子单元为DA'D型稠环结构,缺电子单元(A')通过氮原子与两个给电子单元(D)并联形成稠环结构,这有助于降低前线分子轨道能级并增强吸收,同时与氮相连的两个烷基链和位于噻吩并噻吩β位的两个侧链则有助于提高溶解度及调节结晶性。自Y6问世以来,人们对分子的结构剪裁进行了深入的研究,并报道了数十种新的结构。在这些新的受体中,DA'D部分的结构裁剪对提高器件效率和太阳能电池的性能起着至关重要的作用。本文对A'、D单元和侧链结构修饰的研究进展进行了综述。通过选择几组受体,对最近报道的分子进行分类,并将它们的光学、电化学、电学和光电性质与精确的结构修饰相关联,从而对结构-性能关系进行全面概述。  相似文献   
3.
Herein, we successfully construct the 3D biocompatible graphene through crosslinking 2D graphene nanosheet onto carbon fiber paper with poly(diallyldimethylammonium chloride) (PDDA) as anode of the alcohol biofuel cell. Compared with the bioanode without 3D graphene, the current density and output power of PDDA-graphene-ADH bioanode is increased by 23 % and 41 % at a high concentration of ethanol at pH 8.9, suggesting the stabilization role of graphene in enzyme loading. The study provides us a deep analysis on structures and performances of the bioanode incl. electrochemistry, X-ray photoelectron spectra, and atomic force microscopy images, which is significant to develop the new methods to construct 3D porous electrodes in energy conversion device.  相似文献   
4.
本文主要概述了近年来核酸工具酶辅助的基于金属稳定同位素标记的电感耦合等离子体质谱(ICP-MS)检测方法在生物分析中的发展和应用,简要介绍了该方法在蛋白质、核酸及一些生物小分子检测中的应用。最后对核酸工具酶辅助的基于金属稳定同位素标记的电感耦合等离子体质谱(ICP-MS)检测方法的发展前景做了展望。  相似文献   
5.
In this study, α-glucosidase was successfully immobilized on cellulose filter paper and further applied to screening inhibitors from traditional Chinese medicines combined with capillary electrophoresis analysis. For α-glucosidase immobilization, a cellulose filter paper was used as the carrier and grafted with amino groups by coating chitosan, then α-glucosidase was covalently bonded on the amino-modified carrier via epoxy ring-opening reaction using polyethylene glycol diglycidyl ether as the crosslinker. Several parameters influencing the enzyme immobilization were optimized and the optimal values were enzyme concentration of 4 U/mL, polyethylene glycol diglycidyl ether concentration of 1.25%, chitosan concentration of 7.5 mg/mL, immobilization pH 7.0, crosslinking time of 4 h and immobilization time of 2 h. The immobilized α-glucosidase exhibited good batch-to-batch reproducibility (RSD = 2.1%, n = 5), excellent storage stability (73.5% of its initial activity after being stored at 4°C for 15 days), and reusability (75% of its initial activity after 10 repeated cycles). The Michaelis constant of immobilized α-glucosidase and half-maximal inhibitory concentration of acarbose were calculated to be 1.12 mM and 0.38 μM, respectively. Finally, the immobilized α-glucosidase was used for screening inhibitors from 14 kinds of Traditional Chinese Medicine extracts, and Sanguisorbae Radix showed the strongest inhibitory effect on α-glucosidase.  相似文献   
6.
王慧悦  胡欣  胡玉静  朱宁  郭凯 《化学进展》2022,34(8):1796-1808
原子转移自由基聚合(ATRP)是制备分子量以及分散度可控聚合物的重要途径。然而,受制于除氧步骤复杂、金属催化剂残留以及单体适用范围有限等因素,ATRP难以应用于批量制备功能化聚合物/共聚物材料,限制了其进一步应用。近年来提出和发展的酶催化聚合,为高效便捷除氧、拓展单体适用范围以及制备具有特殊(纳米)结构的纯净聚合物/共聚物提供了新思路。本文详细介绍了酶的结构与催化机理,以酶的种类进行分类,系统总结了具有不同结构的酶催化体系(包括过氧化辣根酶、血红蛋白、血红素、漆酶等)的催化机理、适用单体、优缺点及应用等;综述了酶以及酶模拟物催化ATRP体系的发展现状;最后,对酶催化ATRP的发展前景和挑战进行了探讨和展望。  相似文献   
7.
The oxygen reduction reaction in direct glycol fuel cells heavily relies on noble metal-based electrocatalysts. In this work, novel Pt group metal-free catalysts based on porous Fe-N-C materials are successfully synthesized as catalysts with high activity and durability for the cathode oxygen reduction reaction (ORR). Through the encapsulation of NH4SCN salt, the surface elements and pore structure of the catalyst are effectively changed, and the active sites of Fe effectively are increased. The half-wave potential of the best Fe-N-C catalyst was –0.02 V vs. Hg/HgO in an alkaline environment. The porous Fe-N-C catalyst possesses a large specific surface area(1158 m2/g) and shows good activity and tolerance to glycol. The direct glycol fuel cell with the Fe-N-C cathode achieved a maximum power density of 62.2 mW/cm2 with 4 mol/L KOH and 4 mol/L glycol solution at 25 °C and maintained discharge for more than 250 h at a 50 A/cm2 current density.  相似文献   
8.
王婷  魏奇  付强  李伟  王世伟 《应用化学》2022,39(9):1321-1344
钙钛矿太阳能电池作为第3代新概念太阳能电池,具有高光电转换效率、低成本和可柔性加工等优点,近年来发展迅速,其光电转换效率从一开始的3.8%增长到近期的25.5%,逐渐比肩硅电池,已接近商业化应用水平。目前,实现钙钛矿太阳能电池产业应用的关键环节在于电池封装,它不仅可以解决钙钛矿光伏器件稳定性问题,还可以实现电池安全、环保和延长使用寿命等要求。结合近十几年来钙钛矿光伏电池封装材料和封装工艺两方面的发展现状,文中介绍了钙钛矿电池封装领域取得的成果和存在的不足,讨论了目前现有封装技术的优缺点,以及它们适用的不同器件类型。着重在不同温度湿度条件下,比较了不同封装材料性能、封装工艺条件对钙钛矿电池效率及稳定性的影响,归纳出影响钙钛矿电池薄膜封装效果的3个关键因素: 聚合物的弹性模量、水蒸气透过率、加工温度。比较了不同聚合物薄膜封装材料适宜的加工温度、优缺点及加工成本。可以看出,随着钙钛矿光伏电池工业化需求的强烈增长和人们对其封装材料研究的不断深入,研究适合大面积生产和光伏建筑一体化的新型功能聚合物封装材料将是必然趋势。  相似文献   
9.
Yinlan lipid regulatory capsule (YL) is a composite traditional Chinese medicine (TCM) new drug to alleviate hyperlipidemia, while its therapeutic mechanism in vivo was not clarified with nontargeted metabolomics investigation. An animal model was established in rats fed a high-fat diet, and their body weights, body mass index (BMI) and blood cholesterol levels were measured. Serum, liver and kidney tissue samples were also extracted for PXR-CYP3A4-ABCB1-FXR signaling pathway research using PCR and UHPLC–MS. The obtained plasma samples were analyzed by UHPLC-Q-TOF-MS metabolomic investigation, which revealed PXR-CYP3A4-related metabolites and changes induced by YL. Finally, the key metabolites were chosen as index components, and their levels in the serum, liver, small intestine and bile were used for simultaneous UHPLC–MS-MS determination. The results indicated that YL was effective in rebalancing blood TG and TC levels (compared to controls). With respect to the PXR-CYP3A4-ABCB1 pathway, as a result of YL’s effect, gene expression or activity of the two targets decreased significantly in both the liver and kidney. The same trend was observed in the serum samples mentioned above. Metabolomics screening and data revealed that 44 metabolites can be regarded as biomarkers related to hyperlipidemia, fatty acids synthesis, and body energy consumption, as well as synthesis, transportation and exertion of cholesterol. YL’s treatment focused on 26 of them, primarily bile acids, indicating that the antihyperlipidemic effect of this drug lies in its inhibitory activity of cholesterol metabolism. Subsequent analysis of those in vivo components revealed that significant increases (compared to the model group) occurred in the blood, liver, small intestine and bile in groups that received medium and high doses of YL (while the low dose was relatively unchanged). Those target components exhibit a close relationship with PXR and/or CYP3A4. The use of YL repressed PXR expression and subsequently decreased CYP3A4 activity. As a result, synthesis of related bile acids increased, while cholesterol levels decreased, consequently leading to the attenuation of hyperlipidemia. This study comprehensively investigated the antihyperlipidemia mechanism of YL based on its repression of PXR-CYP3A4 activity and related metabolite yield, establishing an accurate method for evaluating the therapeutic effect of YL.  相似文献   
10.
Purpose of studyOtostegia limbata (Benth.) Boiss. (Family: Lamiacae) is an important underexplored ethnomedicinal plant that has been used as antinflammatory, anticancer and antibacterial herbal remedy previously. The present work was aimed to evaluate the antioxidant, antimicrobial, antileishmanial, and anticancer prospective of O. limbata stem and leaf extracts.ResultsThe highest amount of phenolic and flavonoid content was obtained in the methanol-acetone and methanol stem extracts i.e., 53.29 ± 1.33 and 28.64 ± 1.16, respectively with highest DPPH scavenging in MeH stem extract (IC50 = 34.5 ± 1.34 μg/ml). Significant amount of catechin, gallic acid, apigenin and rutin was quantified. A moderate antibacterial and substantial antifungal activity was observed. Cytotoxicity against brine shrimps categorized 21% of stem (3 out of 14 extracts) and 57% (8 out of 14 extracts) of leaf extracts as potent. Substantial cytotoxicity against THP-1 cell line (IC50 = 3.46 ± 0.25 μg/ml) and Leishmania (IC50 = 1.50 ± 0.23 μg/ml) was exhibited by methanol-distilled water leaf extract while noteworthy antiproliferative activity against Hep-G2 (IC50 = 0.44 ± 0.45 μg/ml) was manifested by n-hexane stem extract. Absence of hemolysis in normal RBCs signified plant’s selective cytotoxicity. Methanol-distilled water and chloroform stem extracts displayed prominent protein kinase inhibition and antidiabetic potential of plant.ConclusionThe results of present study recommend O. limbata as a potential source of antifungal, antileishmanial, anticancer, and α-amylase inhibitory agents.  相似文献   
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