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建立了环境中甾体类激素的生物荧光测定方法.利用睾丸酮丛毛单胞菌的生物酶基因与甾环结构特异的分子识别特性,结合绿色荧光蛋白(GFP)的荧光标记技术,通过基因同源重组技术建立了特异性生物荧光检测系统,实现对环境中甾环类化合物的灵敏监测.制备绿色荧光突变菌及总蛋白含量为1.0 g/L的非细胞体系工作液,在室温条件下对不同浓度雌二醇标准品进行检测,10 min即可检测出fg级的甾体类激素,最佳检测时间为30 min,方法的线性范围1.0~266 ng/L,灵敏度高于高效液相色谱方法.本方法可应用于环境的实际检验工作. 相似文献
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芳烃在原油中的含量仅次于烷烃和环烷烃,因此在油气地球化学勘查工作中,芳烃组分的测定一直是一项重要的研究内容。由于油气化探工作所涉及的样品大多为近地表土壤,而源于油气藏的各芳烃组分在向地表迁移过程中的轻重分异效应,使得各类芳烃组分特别是重芳烃组分在近地表土壤中的含量甚微[1],因此在芳烃组分的高效液相色谱测试中,选择适当的检测波长以便使检测方法达到其最大灵敏度是该技术的关键。1实验部分1.1主要仪器与试剂高效液相色谱仪:HP1090型,美国惠普公司;色谱柱:Hypersil C18柱(30 cm×4.6 mm i.d.,10μm),大连依利特公司;荧光… 相似文献
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粒子束接口液相色谱-质谱应用黄峰(山东大学发酵工程国家实验室济南250100)1前言化学和生物样品中的热不稳定性组分及难挥发性组分无法用气相色谱。质谱进行分析,因此液相色谱。质谱联用倍受关注。近二十年来发展了许多技术,如直接液体导入(directli... 相似文献
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马兜铃酸(aristolochic acid)是马兜铃科植物所含的主要药物成分,属硝基菲类衍生物.但是,近几年有许多报道马兜铃酸具有致癌和致突变作用.动物实验和临床研究表明,马兜铃酸进入人体后,在机体组织中形成马兜铃酸-DNA加合物,进而引起致癌作用.因此,马兜铃酸-DNA加合物现已被用作检测马兜铃酸中毒的生物标记物.本文介绍了当前马兜铃酸-DNA加合物主要的检测方法:32P标记法,高效液相色谱-紫外检测法,高效液相色谱-放射检测法,高效液相色谱-荧光检测法,高效液相色谱-质谱联用法和超高效液相色谱-质谱联用法.本研究也通过实验表明,超高效液相色谱-质谱联用法对马兜铃酸-DNA加合物的检测具有快速、灵敏、专一性和重现性强、定量准确的特点,是马兜铃酸-DNA加合物研究的有力工具.本文最后总结了在不同实验对象和给药剂量的马兜铃酸研究中,马兜铃酸-DNA加合物的检测数据,对马兜铃酸-DNA加合物的研究具有参考价值. 相似文献
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高效液相色谱-荧光-紫外串联测定土壤中16种多环芳烃 总被引:31,自引:0,他引:31
采用高效液相色谱-荧光-紫外检测器串联测定土壤中16种多环芳烃。通过液相色谱柱、荧光激发和发射波长等条件的优化,实现16种多环芳烃组分基线完全分离来和15种多环芳烃荧光高灵敏度检测,并通过荧光-紫外串联检测来提高定性的准确度等。在优化的实验条件下,荧光检测器的检出限为0.015~0.8μg/L;紫外检测器检出限为0.4~30μg/L;方法精密度为0.58%~1.36%(荧光)、1.13%~5.48%(紫外);样品加标回收率为76.4%~111%。 相似文献
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绿色荧光蛋白标记检测枯草芽孢杆菌在水体中的存活动态 总被引:1,自引:0,他引:1
基于生物-化学协同控制植物病害的原理,构建了一种由枯草芽孢杆菌和烯酰吗啉组成的对辣椒等作物疫病具有较好的防治效果的菌药合剂(DMBS)。按照农药降解研究基本规则,采用绿色荧光蛋白(greenfluorescent protein,GFP)标记技术和细菌学研究方法研究了DMBS在去离子水、地下水、自来水、河水和雨水中的降解动态。结果表明,GFP标记可以用于枯草芽孢杆菌在5种水环境中的存活检测。在(25±1)℃条件下,枯草芽孢杆菌菌剂和DMBS中的枯草芽孢杆菌数量主要表现为前12 d迅速下降,此后则随时间的延长在一定的范围内呈变动的上升或下降趋势。在(50±1)℃灭菌和不灭菌的条件下,均表现为前12 d迅速下降,12 d后趋于稳定或缓慢下降。枯草芽孢杆菌在5种水中的降解速度较慢,在(25±1)℃和(50±1)℃条件下存放86 d后,其含量均在104cfu/mL以上。培养温度和灭菌条件对枯草芽孢杆菌在不同水体中存活动态有一定的影响,菌药合剂中的烯酰吗啉对该菌的存活则没有显著影响。 相似文献
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An efficient approach to the synthesis of highly congested di, penta and hexacyclic pyrazoles as well as imidazole fragment containing novel heterocyclic molecule has been developed through a carbanion induced transformation of suitably functionalized 2H-pyran-2-ones, benzo[h]chromene and thiochromeno[4,3-b]pyrans. Due to the presence of fluorescence, we report their prime application metal sensor as off/on switching in ferric ions. 相似文献
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Uroš Grošelj Mojca Žorž Amalija Golobič Branko Stanovnik Jurij Svete 《Tetrahedron》2013,69(52):11092-11108
A new and simple synthesis of novel N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates, which exist in equilibrium with their 4-oxo tautomers, has been developed in two steps starting from N-protected α-amino acids. The key intermediates are enaminones, which can also be isolated, characterized, and used for the construction of other functionalized heterocycles, before they spontaneously decompose to pyrrole products. 4-Hydroxypyrroles are prone to partial aerial oxidation but can be efficiently alkylated or reduced to stable polysubstituted pyrrolidine derivatives. 相似文献
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The chemoselectivity in the intramolecular CH insertion of various diazosulfonamides has been experimentally studied. The results reveal that the aliphatic 1,4-, 1,5-, or 1,6-C(sp3)?H insertions of diazosulfonamides are not accessible, while the aromatic 1,5-C(sp2)?H insertion can be realized specifically by adjusting the diazo-adjacent group. In addition, the general chemoselectivities in the intramolecular CH insertions of diazosulfonyl compounds are summarized. Generally, diazosulfones undergo both aromatic 1,5-C(sp2)?H and aliphatic 1,5- and 1,6-C(sp3)?H insertions, while diazosulfonates undergo aliphatic 1,5- and 1,6-C(sp3)?H insertions. However, diazosulfonamides only undergo aromatic 1,5-C(sp2)?H insertion. 相似文献
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N-Heterocyclic carbene-palladacyclic complexes 3 were successfully achieved in a one-pot procedure under mild conditions. The structure of 3a was unambiguously confirmed by X-ray single crystal diffraction and it was an active catalyst in the Buchwald-Hartwig amination and α-arylation of ketones even at very low catalyst loadings (0.01?mol%). 相似文献
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An efficient tandem approach for the selective synthesis of 4,5-dihydroimidazo[1,5-a]quinoxalines 6a–g and imidazo[1,5-a]quinoxalines 7a–h by the reaction of 2-imidazolyl anilines 4a–c with aryl aldehydes 5a–k under mild reaction conditions is described. Introduction of electron releasing alkyl groups in substrates 4a–b was found to be instrumental for the success of the reaction. 相似文献
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The Diels-Alder reactivity of 1,2-heteroborines (H4C4B(H)X, X?=?NH, PH, AsH; O, S, Se) has been computationally explored by means of Density Functional Theory (DFT) calculations. The influence of the HB?=?X fragment on the reactivity of the system has been quantitatively analyzed in detail by means of the so-called Activation Strain Model (ASM) of reactivity. It is found that the interaction between these species and the dienophile is significantly stronger than that computed for their all-carbon isoelectronic counterpart, benzene. In addition, the strain energy plays a key role in the observed reactivity trends. The role of the aromaticity strength of these heteroarenes on the reactivity is also assessed. 相似文献
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Xi-Liu YunWen-Ying Bi Jian-Hui HuangYu Liu Daisy Zhang-NegrerieYun-Fei Du Kang Zhao 《Tetrahedron letters》2012,53(38):5076-5080
A variety of N-aryl and N-alkyl carbazolones were conveniently achieved in good to high yields via Pd2(dba)3-mediated intramolecular coupling of N-substituted α-iodo enaminones under microwave irradiation. The Pd(0)-catalyzed cyclization was found to proceed favorably with the more electron-deficient phenyl ring during the reactions involving unsymmetrical N,N-diaryl α-iodo enaminones. This unique property enables the construction of carbazolone skeleton containing nitro substituted benzenoid ring. 相似文献
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Shashikant U. Dighe Surya K. Samanta Shivalinga Kolle Sanjay Batra 《Tetrahedron》2017,73(17):2455-2467
An efficient iodine-mediated oxidative Pictet-Spengler reaction in dimethyl sulphoxide (DMSO) using terminal alkynes as the 2-oxoaldehyde surrogate for the synthesis of aryl (9H-pyrido[3,4-b]indol-1-yl)methanones is described. The scope of the protocol includes the total synthesis of Fascaplysin, Eudistomins Y1 and Y2. The methodology is extended for preparing pyrrolo[1,2-a]-quinoxaline and indolo[1,5-a]quinoxaline derivatives. The utility of 1-aroyl-β-carbolines was demonstrated by performing palladium-catalyzed β-carboline directed ortho-C(sp2)-H functionalization of the phenyl ring with thiomethyl (SMe) group using DMSO as source and for accessing 4-aryl-canthin-6-ones. 相似文献
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In this Letter, we described a facile method for constructing fused bicyclic 1-arylpyrazol-5-one ring system. We employed various methylene-containing carboxylic acids as the substrates and proved that the pyrazolone ring closure requires activated methylene group in intermediate II. Accordingly, a series of structurally diversified, fused bicyclic 1-arylpyrazol-5-ones was prepared in moderate to high yields using the requisite substrates. 相似文献
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Both substituted 2,4,5,6-tetrahydrocyclopenta[c]pyrazoles and 2,4,5,6-tetrahydropyrrolo[3,4-c]pyrazoles have been synthesized by the 3+2 intramolecular dipolar cycloaddition of nitrilimines to alkynes. This cyclization has been extended to more versatile 3-bromo derivatives by the use of alkynylbromides as dipolarophiles. 相似文献