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41.
荧光标记法研究鱼类GABA受体与Ro7-1986/1和Fipronil的相互作用 总被引:1,自引:0,他引:1
以苯二氮卓类化合物Ro7-1986/1和氟虫腈(Fipronil)分别与异硫氰酸荧光素(FITC)反应合成了2种γ-氨基丁酸(GABA)受体的配体荧光复合物,即FITC-Ro7-1986/1(简称FITC-Ro7)和FITC-Fipronil;利用傅里叶变换红外光谱(FTIR)和核磁共振氢谱(1H NMR)等手段对其结构进行了表征.以2种荧光配体为探针,采用荧光标记法研究了Ro7-1986/1和Fipronil与鳙鱼(Hypophthalmichthys nobilis)脑内GABA受体的相互作用,得到了亲和常数Kd和最大结合量[RT].同时考察了GABA对Ro7-1986/1与受体相互作用的影响.研究结果表明,Ro7-1986/1和Fipronil与受体的亲和常数Kd分别为(67±5)nmol/L和(346±6)nmol/L;最大结合量[RT]分别为(13.8±1.8)pmol/mg protein和(40.6±3.5)pmol/mg protein;GABA促进了Ro7-1986/1与受体的结合,进一步的研究结果表明,鱼类与哺乳动物脑中GABA受体结构相似;相对于哺乳动物,苯吡唑类杀虫剂Fipronil对鱼类GABA的亲和力较高. 相似文献
42.
Iridium‐ and Osmium‐decorated Reduced Graphenes as Promising Catalysts for Hydrogen Evolution 下载免费PDF全文
Chee Shan Lim Prof. Zdeněk Sofer Rou Jun Toh Alex Yong Sheng Eng Jan Luxa Prof. Martin Pumera 《Chemphyschem》2015,16(9):1898-1905
Renewable energy sources are highly sought after as a result of numerous worldwide problems concerning the environment and the shortage of energy. Currently, the focus in the field is on the development of catalysts that are able to provide water splitting catalysis and energy storage for the hydrogen evolution reaction (HER). While platinum is an excellent material for HER catalysis, it is costly and rare. In this work, we investigated the electrocatalytic abilities of various graphene–metal hybrids to replace platinum for the HER. The graphene materials were doped with 4f metals, namely, iridium, osmium, platinum and rhenium, as well as 3d metals, namely, cobalt, iron and manganese. We discovered that a few hybrids, in particular iridium‐ and osmium‐doped graphenes, have the potential to become competent electrocatalysts owing to their low costs and—more importantly—to their promising electrochemical performances towards the HER. One of the more noteworthy observations of this work is the superiority of these two hybrids over MoS2, a well‐known electrocatalyst for the HER. 相似文献
43.
Theoretical and experimental research on the self‐assembled system of molecularly imprinted polymers formed by salbutamol and methacrylic acid 下载免费PDF全文
The quantum chemical method was applied for screening functional monomers in the rational design of salbutamol‐imprinted polymers. Salbutamol was the template molecule, and methacrylic acid was the single functional monomer. The LC‐WPBE/6–31G(d,p) method was used to investigate the geometry optimization, active sites, natural bond orbital charges, binding energies of the imprinted molecule, and solvation energy. The mechanism of action between salbutamol and methacrylic acid was also discussed. The theoretical results show that salbutamol interacts with functional monomers by hydrogen bonds, and the salbutamol‐imprinted polymers with a ratio of 1:4 (salbutamol/methacrylic acid) in acetonitrile had the highest stability. The salbutamol‐imprinted polymers were prepared by precipitation polymerization. The experimental results indicated that the maximum adsorption capacity for salbutamol toward molecularly imprinted polymers was 7.33 mg/g, and the molecularly imprinted polymers had a higher selectivity for salbutamol than for norepinephrine and terbutaline sulfate. Herein, the studies can provide theoretical and experimental references for the salbutamol molecular imprinted system. 相似文献
44.
Development of an enzyme‐linked immunosorbent assay and immunoaffinity chromatography for glycyrrhizic acid using an anti‐glycyrrhizic acid monoclonal antibody 下载免费PDF全文
Wenhao Zeng Yan Zhao Wenchao Shan Xueqian Wang Qingguo Wang Yan Zhao 《Journal of separation science》2015,38(13):2363-2370
In this work, a new monoclonal antibody specific for glycyrrhizic acid was prepared and characterized. A hybridoma secreting an anti‐glycyrrhizic acid monoclonal antibody was produced by fusing splenocytes from a mouse immunized against a glycyrrhizic acid–bovine serum albumin conjugate with the hypoxanthine–aminopterin–thymidine‐sensitive mouse myeloma cell line (Sp2/0‐Ag14). Subsequently, an indirect, competitive enzyme‐linked immunosorbent assay for glycyrrhizic acid was developed using the monoclonal antibody. In this assay, we detected an effective measuring range of 78.12–2500 ng/mL. Both intra‐assay and inter‐assay repeatability and precision were achieved, with relative standard deviations lower than 10%. In addition, glycyrrhizic acid levels in both formulated Chinese medicines and biological samples were determined with high sensitivity and efficiency. We then successfully developed a reliable immunoaffinity chromatography to separate glycyrrhizic acid completely from its parent medicine. These methods will contribute to further research investigations to better understand the interactions of glycyrrhizic acid with other drugs in the complex system of traditional Chinese medicine. 相似文献
45.
46.
就芬太尼类物质的代谢及近年来对常见生物检材中此类物质的前处理方法及检测方法进行了综述。常见的生物检材有血液、尿液、毛发,这几种检材都具有各自的检测优势和不足。毒品在血液中代谢速度快,代谢产物浓度高,但对检测时效性要求较高;尿液检测前处理简单,代谢产物易检测,但存在易污染、造假的问题;毛发检测不受其他药物影响,可追溯半年内吸毒史,但前处理步骤复杂,成本偏高。生物检材前处理主要包括液液萃取法(LLE)固相萃取法(SPE)和蛋白质沉淀法,SPE更适用于液体样本的前处理,速度更快且节省溶剂,结果重现性更好;LLE的分离效果更好。常用的检测分析方法有免疫分析法、气相色谱质谱联用法(GC-MS)、液相色谱质谱联用法(LC-MS)等。免疫分析法主要用于初筛。GC-M S主要用于分析一些极性小、易挥发、热稳定性好的物质。相对来说,LC-M S灵敏度更高,适用范围更广,目前被广泛应用。提出未来可以从毒品中存在其他类物质是否影响芬太尼类物质的检测、芬太尼的药代动力学及如何通过芬太尼类物质的空间结构准确检测等几个方面进行深入研究。 相似文献
47.
Qun Wang Qiang Xue Tao Chen Jiawei Li Yuehua Liu Xiaohan Shan Fei Liu Jianbo Jia 《中国化学快报》2021,32(2):609-619
The abuse of antibiotics will cause an increase of drug-resistant strains and environmental pollution,which in turn will affect human health.Therefore,it is important to develop effective detection techniques to determine the level of antibiotics contamination in various fields.Compared with traditional detection methods,electrochemical sensors have received extensive attention due to their advantages such as high sensitivity,low detection limit,and good selectivity.In this mini review,we summarized the latest developments and new trends in electrochemical sensors for antibiotics.Here,modification methods and materials of electrode are discussed.We also pay more attention to the practical applications of antibiotics electrochemical sensors in different fields.In addition,the existing problems and the future challenges ahead have been proposed.We hope that this review can provide new ideas for the development of electrochemical sensors for antibiotics in the future. 相似文献
48.
Shan Jiang Lingchen Meng Wenyue Ma Qingkai Qi Wei Zhang Bin Xu Leijing Liu Wenjing Tian 《中国化学快报》2021,32(3):1037-1040
Luminescent conjugated network polymer is one of the most promising chemo-sensors owing to their good chemical/optical stability and multiple functionalization.Herein,three conjugated network polymers were prepared by using aggregation-induced emission active 1,1,2,2-tetrakis(4-formyl-(1,1'-biphenyl))-ethane(TFBE) unit as monomer and hydrazine as linker.Through regulating the synthetical condition,the polyme ric network can form either unifo rm two-dimensional azine-linked nanosheets(ANS),conjugated microporous polymers(A-CMP) or covalent organic frameworks(A-COF).All of these polymers exhibited good stability and high fluorescence quantum efficiency with the quantum yield of6.31% for A-NS,5.26% for A-CMP,and 5.80% for A-COF,as well as fast and selective fluorescence quenching response to 2,4,6-trinitrophenol(TNP).And the best TNP sensing performance with the Stern-Volmer constants(K_(sv)) values up to 8 × 10~5 L/mol and a detection limit of 0.09 μmol/L was obtained for A-NS.The study explores various strategies to construct conjugated polymers with different nanoarchitectures based on the same building block for sensitive detection of explosives. 相似文献
49.
Disclosed herein is an efficient Ag-catalyzed 4+1 heteroannulation reaction of enamides with α-carbonyl sulfoxonium ylides.The diastereoselective transformation provides a practical access to a diverse range of multi-functionalized oxazoline derivatives.The synthetic utility of the resultant tetrasubstituted oxazolines is further demonstrated by a series of useful manipulations into valuable building blocks of pharmaceutical relevance. 相似文献
50.
以氨丙基三乙氧基硅烷和草酰氯为原料,合成得到链上含亚氨基和羰基官能团的硅氧倍半聚合物。以此聚合物为载体,通过配位吸附和还原得到银纳米粒子(平均粒径约为15 nm)高度分散于硅氧烷聚合物表面的复合物。研究结果表明,复合物中银负载量(质量分数)约为13.66%,在水溶液中25℃、6 min内可将对硝基苯酚(4-NP)完全催化还原为对氨基苯酚(4-AP),且7次循环使用后依然保持95%以上的催化活性。在常温常压条件下,催化剂的最高活性达到33.0 g4-AP·gAg-1,表现出优异的催化还原性能。 相似文献