消耗型化学发光传感器的研究

本文首次发展了多种消耗型化学发光传感器, 方法基于发光试剂通过电价键全部固定在阴、阳离子交换树脂上, 在不添加外来发光试剂的情况下, 可直接对待测物进行传感。该类型传感器固定化方法简单, 灵敏度高, 还可通过控制洗脱剂的浓度精确控制发光试剂的释放量, 进而控制固定化试剂柱的使用寿命。所设计的六种类型的传感器均已成功地应用于样品中待测物的测定。     

乙酰胆碱和胆碱化学发光生物传感器的研究

将具有分子识别功能的乙酰胆碱酯酶和胆碱氧化酶及进行换能反应的luminol和Cu^2^+分别固定在多孔玻璃和离子交换剂的柱中,组成流动注射式胆碱和乙酰胆碱化学发光传感器,让传感器分子识别反应和换能反应在各自最佳pH值下进行。这一新型生物传感器优化了发光量子产率,避免了在传感元件上直接发光所产生的散射干扰。测定乙酰胆碱和胆碱的线性范围达到1～1000pmol,检测限为500fmol,每次测定时间为2min,寿命为6个月,已用于鼠脑及人血清中乙酰胆碱和胆碱的测定。     

基于固定化纳米金增强化学发光双酶传感器测定葡萄糖

研制了一种新型流动注射化学发光（CL）双酶传感器,用于葡萄糖的检测．该传感器将掺杂金纳米粒子（GNPs）的壳聚糖膜包覆在硅烷化试剂预处理的玻璃微珠上,用于吸附固定葡萄糖氧化酶（GOD）和辣根过氧化物酶（HRP）．葡萄糖在GOD的催化下发生氧化反应生成H2O2,生成的H2O2在HRP的催化作用下与鲁米诺发生反应,并产生化学发光信号．实验表明,壳聚糖中掺杂的GNPs不仅能够有效的吸附酶分子并保持其生物活性,还对Luminol-H2O2-HRP化学发光体系具有增敏作用．通过化学发光光谱和紫外光谱表征,详细研究了固定化GNPs增强Luminol—H2O2-HRP体系的化学发光机理．在优化的实验条件下,该传感器对葡萄糖检测的线性范围为0．01～6．0mmol／L,检测限为5．0μmol／L（3σ）．将所建立的方法用于临床血清样品中葡萄糖含量的测定,获得了满意的结果．     

固定化酶柱流动注射化学发光分析法测定人体血液中的葡萄糖

本文将葡萄糖氧化酶包埋在聚丙烯酰胺凝胶中使之固定化,并将其装柱接入流动注射系统中,用流动注射化学发光法测定葡萄糖通过固定化酶柱后转化生成的过氧化氢,从而测定葡萄糖含量。该法灵敏、快速、准确、酶柱性能稳定,可反复使用。葡萄糖的检测下限小于0.1mg/L,经人体血糖测定和加标准回收实验结果均为满意。     

在线二氧化氮化学发光测定仪的研制

基于NO2与鲁米诺溶液的化学发光反应设计制作了在线NO2的化学发光测定仪,并对此仪器进行了优化和表征。仪器由微型流动气液界面化学发光反应器、气液输运系统、化学发光检测系统及数据采集系统组成。此仪器测定NO2的线性范围为5.0×10-11～8.0×10-8(V/V,体积比浓度,下同);峰值响应时间少于1s;时间分辨1s;检出限为5.0×10-11(V/V)。本仪器具有结构简单、体积小、成本低等特点,适用于环境大气中NO2的实时在线测定。     

测定锰(Ⅱ)离子的KIO4-K2CO3化学发光体系

碱性介质中 ,KIO4与二价锰离子反应 ,在没有任何化学发光试剂存在条件下产生微弱的化学发光。当向体系中加入碳酸盐后 ,反应产生的化学发光显著增强 ,且该发光强度与Mn2 浓度在 1× 1 0 -8～ 5× 1 0 -6mol L范围内成线性关系 ,测定检出限为 5× 1 0 -9mol L。基于这一现象 ,同时结合流动注射分析技术 ,建立起了一种测定环境水中微量Mn2 的化学发光新方法     

高效液相色谱光度法测定痕量铜、锌、铁、锰的磺化四苯基卟啉配合物

本文用磺化四苯基卟啉作柱前衍生试剂,研究了试剂与铜(Ⅱ)、锌(Ⅱ)、铁(Ⅲ)及锰(Ⅱ)的络合反应。在ODS柱上,用乙腈-水(40:60,V/V)作流动相,溴化四丁基铵作离子对试剂,在420nm波长处进行光度检测。提出了离子对反相高效液相色谱快速分离及测定痕量铜、锌、铁及锰的新方法。检测下限为(×10^-3ppm):Mn 3.6、Fe 1.8 、Zn 0.93、Cu 0.70。应用于植物样品中痕量铜、锌、铁及锰的测定,分析结果与标准参考值相符。     

流动注射分析光泽精-H2O2-Pb(Ⅱ)化学发光体系测定痕量铅的研究

检测铅离子常用的方法有AAS法和双硫腙比色法,前者直接测定工业废水中的铅,灵敏度不高;后者操作步骤繁琐,须使用剧毒试剂氰化钾,污染环境,用流动注射化学发光法测定铅,仪器简单、操作简便、试样消耗量少、精密度高、分析快速准确、自动化程度高。     

高效液相色谱电生Mn(Ⅲ)化学发光法检测人体血清和尿样中的卡托普利

设计了一个HPLC在线电生Mn(Ⅲ)化学发光检测器, 实现在线电化学反应, 从而产生反应活性很高的初生态氧化剂Mn(Ⅲ), 并与色谱柱后CP混合产生化学发光. 同时还能够根据需要调节电极反应和发光反应两者的介质, 满足柱后发光反应的最佳环境. 在优化流动相和化学发光检测条件的基础上, 将该检测器应用于人体血清和尿液中CP的测定.     

Luminol-H2O2化学发光法测定汽油中铅

利用铅(Ⅱ)催化H2O2氧化Luminol产生化学发光的反应,采用流动注射分析技术,在分离共存干扰离子基础上,在鲁米诺中加入EDTA作为增敏试剂,有效提高了测试反应的检测灵敏度,对分解后的汽油样品中铅(Ⅱ)含量进行了化学发光法测定,铅(Ⅱ)的含量在0.5～100μg@ml-1内与发光强度呈线性关系,方法检出限达0.1μg@ml-1.     

二氧化碳和丙烯直接合成甲基丙烯酸的NiPMo/TiO2催化剂的研究

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%.     

Synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives

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.     

A general and convenient synthesis of 4-(tosylmethyl)semicarbazones and their use in amidoalkylation of hydrogen,heteroatom, and carbon nucleophiles

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.     

Toward new camptothecins. Part 6: Synthesis of crucial ketones and their use in Friedländer reaction

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.     

Synthesis of novel chiral bidentate hydroxyalkyl-N-heterocyclic carbene ligands and their application in palladium-catalyzed Mizoroki–Heck couplings and asymmetric addition of diethylzinc to benzaldehyde

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.     

α-Amino acid derived enaminones and their application in the synthesis of N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates and other heterocycles

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.     

Specific intramolecular aromatic CH insertion of diazosulfonamides

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.     

CoFe2O4自形成磁性液体场致结构化对磁化的影响

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.     

Microwave-assisted copper-catalyzed stereoselective ring expansion of three-membered heterocycles with α-diazo-β-dicarbonyl compounds

Microwave-assisted copper-catalyzed ring expansions of three-membered heterocycles with α-diazo-β-dicarbonyl compounds were investigated. Thiiranes generated 3-acyl-5,6-dihydro-1,4-oxathiines in the presence of copper sulfate and trans-3-acyl-5,6-dihydro-1,4-oxathiines as stereospecific products for 1,2-disubstituted cis-thiiranes through an intramolecular S_N2 process. Oxiranes gave rise to 2-acyl-5,6-dihydro-1,4-dioxines under the catalysis of copper hexafluoroacetylacetonate and cis-3-acyl-5,6-dihydro-1,4-dioxines as stereospecific products for 1,2-disubstituted cis-oxiranes via an intimate ion-pair mechanism. The current method provides a direct and simple strategy in efficient preparation of 3-acyl-5,6-dihydro-1,4-oxathiines and 2-acyl-5,6-dihydro-1,4-dioxines, important agents in medicinal and agricultural chemistry, from readily available thiiranes and oxiranes, respectively.     

KMnO4-mediated oxidative CN bond cleavage of tertiary amines: Synthesis of amides and sulfonamides

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.