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1.
本文用Ferrocene(FC)作为黄嘌呤氧化酶与电极之间的电子传递体,通过牛血清白蛋白和戊二醛交联剂,把黄嘌呤氧化酶固定在Nafion-Fc修饰电极表面,制备成次黄嘌呤传感器。该传感器的线性范围为5.0×10-5—7.5×10-4mol/L,响应时间小于7os。  相似文献   

2.
四硫富瓦烯为电子媒介体的葡萄糖生物传感器的研究   总被引:2,自引:0,他引:2  
本采用四硫富瓦烯(TTF)作为葡萄糖氧化酶与玻碳电极之间的电子媒介体,把葡萄糖氧化酶因定在Nafion-TTF修饰电极上,制成葡萄糖生物传感器。用这种传感器测定人体血清中葡萄糖的含量,其线性范围在4.0×10^-5~10^-3mol/L之间,响应时间为20s。该传感器具有选择性、重现性好,灵敏度高等优点。  相似文献   

3.
用四硫富瓦烯作为酶与电极之间的电子传递体,通过Nafion水溶液把葡萄糖氧化酶固定在Nafion-TTF修饰玻碳电极上,最后在电极上装饰一层Nafion膜,制备成葡萄糖传感器。Nafion膜不仅能防止四硫富瓦烯流失,而且能把抗坏血酸、尿酸等电活性物质阻挡在电极外,防止其干扰,同时具有防污性能。通过实验表明TTF^+1、TTT^+2都能够氧化葡萄糖氧化酶中的辅酶。该传感器的线性范围为3.0×10^-  相似文献   

4.
郭黎平  孙长青 《分析化学》1994,22(2):125-128
本研究了一种将电子介体四硫富瓦烯(TTF,Tetrathiafulalene)引入葡萄糖氧化酶微电极的新方法,制成了TTF为介体的碳纤维束葡萄氧化酶微电极。该电极制作简单,响应迅速,灵敏,电极寿命可达15天。葡萄糖浓度在1.0×10^-^4-1.5×10^-^3mol/L范围内有线性关系,检出限为7×10^-^5mol/L。用于人体血样中葡萄糖测获得满意结果。  相似文献   

5.
黄铁华 《分析化学》1998,26(6):748-751
报道了使用微柱色谱和电化学检测器测定鼠脑微透析液中神经传递物质的方法。儿茶酚胺,5-羟色胺和代谢物的检测限为 0. 1~0. 5 pg。含有乙酰胆碱酯酶和胆碱氧化酶的柱后反应器使分离后的乙酰胆碱和胆碱转化成过氧化氢.再用铂电极或过氧化物酶修饰过的玻碳电极检测过氧化氢。乙酰胆碱的检测限当使用怕电极时是50× 10-15mol,当使用酶修饰电极时是10×10-15mol。  相似文献   

6.
伏安式多酚氧化酶电极的研究   总被引:1,自引:0,他引:1  
屠一锋  刘宇 《分析化学》1994,22(9):967-969
本报道了一种能性能良好的以吩嗪甲酯(PMS)修饰的玻碳电极为基体电极的优安式多酚氧化酶电极。采用从蘑菇中粗提取的多酚氧化酶固定於电极表面,可用循环伏安法测定5×10^-^7mol/L的多巴胺。本首次采用丙烯酸丁酯-丙烯酸甲酯共聚乳液固定酶,所制得电极性能与戊二醛交联法所得电极基本相同。在降低电极充电电流方面,采用半微分技术使电极性能得到很大改善,测定灵敏度达到2.5×10^-^7mol/L,且  相似文献   

7.
用扫描电镜分析了再生丝素(RSF)和聚乙烯醇(PVA)混合膜的形貌结构,并测定了其吸水性和机械强度,用RSF和PVA的混合材料把葡萄糖氧化酶固定在玻碳电极表面,制成电流型葡萄糖传感器。以1,4-苯醌为电子传递体,酶电极对葡萄糖有灵敏的响应,峰电流的增加与葡萄糖的浓度在10^-5-10^-2mol/L范围内良好的线性关系。用此方法制成的葡萄糖传感器物理性能好,其有效寿命长达2个月以上,该酶电极对葡萄  相似文献   

8.
亚甲蓝作为酶电极电子传递介体的性能研究   总被引:1,自引:0,他引:1  
研究了亚甲蓝修饰的玻碳电极的催化性能,并以此电极为基础电极研制了介体修饰型多酚氧化酶电极,对多巴胺测定的检出限为5×10-6mol/L,较空白电极降低了400倍,而对维生素C的响应则显著减小,其电流值降低至空白电极的十分之一.因此不仅显著提高了灵敏度,选择性也得到很大的改善.  相似文献   

9.
铁卟啉修饰电极催化氧化测定儿茶酚类化合物   总被引:2,自引:0,他引:2  
将铁卟啉氯化-5,10,15,20-四-(-3-甲氧基-4-羟基苯基)卟啉铁(TMHPP·FeCl)修饰在玻碳电极表面,制备成对儿茶酚类化合物具有高的响应的TMHPP·FeCl修饰电极。该电极对多巴胺、肾上腺素等儿茶酚类化合物在各自的响应区间内有良好的线性关系,电极具有灵敏度高、响应快、稳定性好等特点。电极响应时间小于10s,儿茶酚类检测浓度在10(-6)mol/L数量级。  相似文献   

10.
聚碱性品红修饰电极的制备及应用   总被引:31,自引:0,他引:31  
研究了碱性品红在玻碳电极上聚合的最佳实验条件及其聚合机理,发现该修饰电极的多巴胺具有良好的催化作用,能大大提高多巴胺在的玻碳电极上的响应,在pH=7.0的磷酸盐缓冲溶液中,用修饰电极测定巴胺的线性范围为2×10^-7~1×10^-5mol/L,检测限为1×10^-7mol/L,并且具有稳定性好,响应快,选择性等特点。  相似文献   

11.
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   

12.
Different approaches for the synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives from simple amino acids have been investigated. A library of 33 precursors for the preparation of N-hydroxy pyrazinones was obtained in moderate to good yields.  相似文献   

13.
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   

14.
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   

15.
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   

16.
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   

17.
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   

18.
Zhanhui Yang  Shiyi Yang  Jiaxi Xu 《Tetrahedron》2017,73(23):3240-3248
Regiospecific and direct imidation of the methyl C(sp3)–H bond of thioanisoles is realized under mild and metal-free conditions with N-fluorobis(benzenesulfonyl)imide as an oxidant and nitrogen source. Proposed mechanism suggests that thionium ion intermediates and a Pummerer-type reaction are involved. The imidation has advantages such as high step-economy, excellent functionality tolerance, and regiospecificity, giving structurally diverse imidation products.  相似文献   

19.
A general synthesis of previously unknown semicarbazone-based α-amidoalkylating reagents, 4-(tosylmethyl)semicarbazones, has been developed. The synthesis involved three-component condensation of semicarbazones of aliphatic or aromatic aldehydes with the same or other aldehydes and p-toluenesulfinic acid. The scope and limitations of this reaction were investigated. The compounds obtained were demonstrated to be an efficient α-(4-semicarbazono)alkylating agents. They were reacted with H- (sodium borohydride), O- (sodium methylate), S- (sodium phenylthiolate), N- (pyrrolidine, sodium succinimide), P- (trialkyl phosphites), and C-nucleophiles (sodium diethyl malonate) to give the corresponding products of the tosyl group substitution, 4-substituted semicarbazones, including analogues of nitrofurazone. Among the prepared compounds tested in vitro for antibacterial and antifungal activity, three nitrofuryl-containing semicarbazones exhibited high biological activities with minimum inhibitory concentration (MIC) values of 8–32 μg/mL.  相似文献   

20.
A small library of new chiral bidentate hydroxyalkyl-imidazolium salts 1 is conveniently synthesized on multi-gram scale from inexpensive and commercially available chiral pool amino acids. The corresponding carbenes, generated by deprotonation of imidazolium salts 1, in combination with palladium(II) chloride were tested in the Mizoroki–Heck coupling reaction. The most significant results in terms of yields and reactivities were achieved with low catalyst loading. The catalytic activities of these imidazolium salts were also investigated in the asymmetric addition of diethylzinc to benzaldehyde. The use of MgO nanoparticles as an additive in conjunction with these ligands played a crucial role in increasing the efficiency of these reactions.  相似文献   

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