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基于血红蛋白的过氧化物酶特性测定其在血浆中游离态含量 总被引:2,自引:0,他引:2
基于血红蛋白 (Hb)的过氧化物酶特性 ,研究了以铬黑T(EBT)作为其氢供体底物时的酶动力学行为。实验测定了Hb作为辣根过氧化物酶 (HRP)的替代物的类酶催化米氏常数和米氏速率。对Hb催化H2 O2 氧化铬黑T的机理作了探讨。建立了测定Hb的催化动力学光度法 ,方法的线性范围为 2× 10 - 8mol/L~ 2× 10 - 6mol/L ,检出限为 3.6× 10 - 9mol/L。用于血浆中游离Hb的测定 ,结果满意。 相似文献
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基于静电吸附多层膜固定酶的过氧化氢生物传感器的研究 总被引:17,自引:2,他引:15
以玻碳电极为基底,电聚合2,6-吡啶二甲酸(PDC),使形成一带负电的界面,再通过静电吸附自组装一层聚阳离子聚丙烯胺(PAH),用于静电吸附固定辣根过氧化物酶并以此方法固定多层酶膜制备过氧化氢传感器.探讨了工作电位、介体浓度、pH对电极响应的影响,考察了电极的重现性、干扰及使用寿命.该传感器在H2O2浓度4.6×10-6~3.5×10-3 mol/L范围内有线性响应, 检出限为2×10-6 mol/L.电极在用于实际试样回收率的测定中,结果良好. 相似文献
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基于伴刀豆球蛋白固定过氧化物酶无介体新型生物传感器的研制 总被引:2,自引:0,他引:2
以纳米金吸附辣根过氧化物酶,用活化的伴刀豆球蛋白(Con A)将其固定在裸金电极表面,研制成一种新型的无介体辣根过氧化物酶生物传感器。探讨了纳米金的尺寸、组装膜层数、工作电位和pH等实验条件对传感器性能的影响。在pH7.0,外加电压-150mV(vs.SCE)条件下,传感器对H2O2在5.0×10-6~1.2×10-2mol/L范围内呈线性关系;检出限为2.9×10-6mol/L。将传感器用于实际样品的测定,结果良好。 相似文献
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基于SiO2纳米粒子固定辣根过氧化物酶的生物传感器 总被引:22,自引:0,他引:22
制备了尺寸均一的SiO2纳米粒子(60nm),并将其用于固定辣根过氧化物酶.以儿茶酚为电子媒介体制得的H2O2传感器的检测范围为1.7×10-7~1.9×10-5mol/L,检出限为8.3×10-8mol/L.达到95%稳态电流所用时间少于10s.该传感器的米氏常数为7.8μmol/L,表明所固定的酶具有较高的生物活性. 相似文献
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Nafion-二茂铁-双酶修饰的葡萄糖传感器 总被引:8,自引:0,他引:8
用二茂铁作为过氧化物酶与玻碳电极的电子传递体,通过牛血清白蛋白-戊二醛交联剂把葡萄糖氧化酶和过氧化物酶固定在Nafion-二茂铁修饰玻碳电极上,制备成葡萄糖传感器。由于工作电位低,电活性物质如抗坏血酸、尿酸等对测定无干扰。该传感器的线性范围为5.0×10~(-4)~2.5×10~(-2)mol/L,响应时间小于30s. 相似文献
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通过溶胶-凝胶技术制备SiO2/Nafion杂化膜并固定辣根过氧化物酶,以杂化膜中Nafion固定的亚甲基蓝为辣根过氧化物酶和玻碳电极间的电子传递介体,制成了电流型过氧化氢生物传感器。探讨了杂化膜的制备条件、工作电位、pH值、温度、干扰物质等对生物传感器的影响。该生物传感器的线性响应范围为1.0×10-6~1.6×10-4mol/L,检出限(S/N=3)为6.0×10-7mol/L,达到95%稳态响应电流用时少于15s。固定化酶对过氧化氢催化反应的米氏常数为1.129 mmol/L。 相似文献
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血红蛋白与葡萄糖氧化酶偶联荧光法测定葡萄糖 总被引:9,自引:1,他引:9
利用血红蛋白(Hb)作为辣根过氧化物酶(HRP)的模拟酶,催化H2O2与对甲基酚的荧光反应.并将该反应与葡萄糖氧化酶(GOD)催化氧化葡萄糖的反应偶联,建立了测定葡萄糖的荧光分析法.方法的线性范围为0.0~5.0×10-5mol/L葡萄糖.检测限为6.5×10-8mol/L.用于测定人血清中葡萄糖的含量,获得了满意的结果. 相似文献
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用溶胶-凝胶法以磷钼酸(MPA)的镍盐溶液水解钛酸四丁酯制备了NiPMo/TiO2催化剂.使用ICP、 XRD、 TG-DTA、 IR、 TPD-MS和微反应技术研究了催化剂的化学组成、热稳定性、化学吸附性质和催化反应性能.杂多钼酸盐与TiO2通过O2-在TiO2表面发生了键合.在623 K下,杂多阴离子仍保持原有的Keggin结构.CO2在Lewis酸位Ni(Ⅱ)和Lewis碱位Ni-O-Mo的桥氧协同作用下生成CO2卧式吸附态Ni(Ⅱ)←O-(CO)←(O--Ni).丙烯有多种吸附态在催化剂上吸附.在563 K、 1 MPa和空速1500 h-1的反应条件下,丙烯的摩尔转化率为3.2%,产物MAA选择性为95%. 相似文献
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Toward new camptothecins. Part 6: Synthesis of crucial ketones and their use in Friedländer reaction
Laurent Gavara Thomas Boisse Jean-Pierre Hénichart Adam Daïch Philippe Gautret 《Tetrahedron》2010,66(38):7544-5571
In the context of the preparation of camptothecin and luotonin A analogs, the synthesis of some key keto-precursors and their use in Friedländer condensation are described. This paper also focuses on the stability of these keto intermediates and emphasizes the major differences between indolizinones and pyrroloquinazolinones series. Noteworthy is also the report of some original structures isolated as by-products of some experiments. 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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The Langevin paramagnetic theory can’t describe the relation between magnetization of ferrofluids and applied magnetic field. The structuralization of ferrofluids, which is considered the main influence factor of the magnetization, is regarded. The part of magnetization works is deposited when the structure is forming. This action influences the magnetization of ferrofluids directly or indirectly. On the base of the “compressing” model, the Langevin function that usually describes the magnetization of ferrofluid is modified, and a well-fitted curve is obtained. An equation of the relation between the equivalent volume fraction after being “compressed” and the intensity of magnetic field is discovered, which approximately describes the process of magnetization. The relation between the approximate initial susceptibility and the volume fraction can be obtained from modified formula. 相似文献
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KMnO4-mediated oxidative CN bond cleavage of tertiary amines producing secondary amine was introduced, which was trapped by electrophiles (acyl chloride and sulfonyl chloride) to form amides and sulfonamides. The reaction could take place at mild condition, tolerating a wide range of function groups and affording products in moderate to excellent yields. 相似文献
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N. A. Nedolya 《Chemistry of Heterocyclic Compounds》2008,44(10):1165-1219
The review contains a concise historical account and information on the most significant researches undertaken by the staff
at the A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences on the Chemistry
of Heterocyclic Compounds.
Dedicated to Academician of the Russian Academy of Sciences B. A. Trofimov on his 70th jubilee.
Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1443–1502, October, 2008. 相似文献
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Rebecca J. Burton Mandy L. CrowtherNeal J. Fazakerley Shaun M. FilleryBarry M. Hayter Jason G. KettleCaroline A. McMillan Paula PerkinsPeter Robins Peter M. SmithEmma J. Williams Gail L. Wrigley 《Tetrahedron letters》2013
The highly regioselective Buchwald–Hartwig amination at C-2 of the cheap and readily accessible reagent, 2,4-dichloropyridine with a range of anilines and heterocyclic amines is described. This new methodology is robust and provides a facile access to 4-chloro-N-phenylpyridin-2-amines on 0.25 mol scale. These intermediates undergo a further Buchwald–Hartwig amination at higher temperature to enable rapid exploration of the chemical space at C-4 and to provide a library of 2,4-bisaminopyridines. 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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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