基于多壁碳纳米管-硫堇/Nafion纳米复合物修饰的人IgG免疫传感器的研究

制备了基于多壁碳纳米管-硫堇/Nafion纳米复合物的人IgG免疫传感器.阻抗谱、循环伏安研究表明,该免疫传感器对人IgG的检测具有优异的性能,其对人免疫球蛋白G(IgG)浓度的定量测定线性范围为1.0 ～ 200μg/L,检出限为0.25 μg/L,线性相关系数R=0.9950.该免疫传感器可用于对人血清中IgG的检...     

基于3,5-二溴水杨醛席夫碱镍配合物-氧化石墨烯电化学免疫传感器检测Anti-IgG含量的研究

应用物理吸附法将羊抗人IgG抗原直接固定于3,5-二溴水杨醛席夫碱镍配合物-氧化石墨烯修饰的金电极表面,制备电化学免疫传感器。采用循环伏安法和交流阻抗法对传感器进行表征,结果表明该传感器适合检测Anti-IgG浓度。同时探讨了缓冲液pH值、扫描速度、免疫反应温度、抗原与抗体配比对循环伏安峰电流的影响,结果表明在5~100mV/s扫速范围内,峰电流与扫速呈线性。孵育最优条件为25℃,h-IgG与Anti-IgG配比为1∶1。循环伏安法研究还表明Anti-IgG浓度在0.01~260μg/L范围内,线性关系良好,相关系数r2=0.993,检出限(S/N=3)为0.006μg/L,据此建立了检测Anti-IgG浓度的新方法。     

基于纳米金/壳聚糖/石墨烯的癌胚抗原阻抗型免疫传感器

研究了在PBS缓冲介质中,一种检测癌胚抗原的新型免标记阻抗型免疫传感器的制备及应用,基于石墨烯、纳米金在玻碳电极表面组装制备传感器,通过循环伏安法、交流阻抗法对制备的传感器进行表征。在优化的实验条件下,该免疫传感器的阻抗值随着检测溶液中癌胚抗原(CEA)浓度的增大而增大,并在0.1～85 ng/mL CEA范围内呈线性关系,回归方程为△Ret=1605.55+39.26ρ;检测限为0.04 ng/mL(R=0.9992)。该免疫传感器可用于临床上对CEA的检测。     

电位无标型糖化血红蛋白免疫微传感器

研制了基于标准CMOS工艺和微加工技术的电位无标型免疫微传感器,可实现糖化血红蛋白浓度与血红蛋白浓度的简便检测。该微传感器包括含有信号读出电路的场效应型微传感集成芯片和一次性测试试条。微传感集成芯片由本实验室设计并经新加坡Chartered半导体公司流片制备。一次性测试试条采用微加工技术制备于柔性塑料片上,包括敏感电极阵列和三维微结构测量池。基于自组装单层膜并引入纳米金颗粒的方法,在测试试条电极表面固定抗体。采用循环伏安法和交流阻抗法对电极表面的修饰过程进行了测试和分析。该传感器对糖化血红蛋白和血红蛋白检测的线性范围分别为4～24mg/L和60～180mg/L。     

基于水滑石-金纳米粒子的阻抗型核酸适配体传感器的研究

在玻碳电极表面用电化学沉积法一步合成钴铝水滑石-金纳米粒子(CoAl LDH-GNPs)复合纳米材料,以复合纳米材料作为核酸适配体(Apt)的固定化基质,建立了一种高灵敏的阻抗型适配体传感器.采用扫描电镜(SEM)和能量色散谱仪(EDS)对CoAl LDH-GNPs复合纳米材料进行了表征,对电极的组装过程采用循环伏安法和电化学阻抗进行表征,对传感器的性能采用电化学阻抗进行研究.复合纳米材料CoAl LDH-GNPs构筑的传感器对凝血酶(THR)具有良好的信号响应,线性相关系数R=0.995,检出限为0.3 ng/L(S/N=3),检测范围为1.0 ng/L～ 100 μg/L.     

水胺硫磷分子印迹传感器的制备与应用

在磷酸盐缓冲溶液(PBS)中,以邻苯二胺(o-PD)和没食子酸(GA)为功能单体,水胺硫磷(ICP)为模板分子,采用电位循环扫描法在玻碳电极(GCE)表面进行电聚合,形成绝缘性的分子印迹膜,通过电化学阻抗谱(EIS)和循环伏安法(CV)对分子印迹膜进行表征.在最佳实验条件下,以铁氰化钾[ K3Fe(CN)6]为探针,用差分脉冲伏安法( DPV)对ICP进行定量分析.该传感器在2.00×10 -7～2.00×10-4 mol/L范围内,传感器的响应信号与ICP的浓度呈良好的线性关系,检测限为6.06×10-s mol/L( S/N=3).将其用于蔬果等实际样品中ICP的测定,回收率为95.6％～104.0％.     

以聚硫堇为电化学探针的非标记型核酸适配体传感器

采用电聚合法制备了聚硫堇氧化还原电化学探针, 以金纳米粒子为固定核酸适配体的载体构建了非标记型核酸适配体传感器. 用电化学阻抗谱对传感器的组装过程进行了监测, 用循环伏安法和差分脉冲伏安法考察了传感器的电化学行为. 结果表明, 该传感器对凝血酶的检测在1.0 pg/mL～500 ng/mL范围内呈良好的线性关系, 相关系数为0.998, 检出限为0.38 pg/mL. 该传感器制备简单、 灵敏度高且抗干扰能力强.     

半胱氨酸封闭剂为电化学探针的非标记型核酸适配体传感器

采用半胱氨酸为封闭剂和氧化还原电化学探针,制备了一种新型的非标记型电化学核酸适配体传感器,并用于测定凝血酶。 利用电化学阻抗对传感器的组装过程进行了监测。 用循环伏安法和差分脉冲伏安法研究了该传感器的电化学行为。 探讨了凝血酶孵育时间、测试pH值对传感器响应的影响。 该传感器对凝血酶在10.0~10000 μg/L范围内呈良好的线性响应,检测限为2.47 μg/L。     

对羟基苯甲酸分子印迹传感器的制备及其性能研究

采用简单高效的分子印迹膜技术,制备了对羟基苯甲酸(PHA)分子印迹传感器。敏感膜采用循环伏安法(CV)在玻碳电极表面合成,采用CV、微分脉冲伏安法、线性扫描伏安法和电化学交流阻抗法在K3[Fe(CN)6]/K4[Fe(CN)6]溶液中测试此分子印迹传感器的性能。在最优条件下,PHA检测线性范围为0.6～8.0μmol/L,检测限(S/N=3)为0.2μmol/L。实验结果表明:该分子印迹传感器灵敏度高、选择性好并且具有良好的再生性能,传感器对与PHA结构相似的分子有较强的抗干扰能力,可望用于植物体分泌化感物质PHA的实时监测。     

基于纳米结构双层类脂膜的雌激素传感器

采用铂盘电极支撑的纳米金修饰的双层类脂膜(Pt/BLM/Au)来固定雌激素受体(ER),制备Pt/BLM/Au/ER用于检测雌激素的传感器.电极不同修饰状态分别用循环伏安法和交流阻抗法进行表征.以交流阻抗法测得电极结合雌激素后阻抗的改变与17β-雌二醇(E2)的浓度在5～150 ng/L范围呈良好线性关系,相关系数r=...     

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%.     

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.     

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.     

Highly regioselective Buchwald–Hartwig amination at C-2 of 2,4-dichloropyridine enabling a novel approach to 2,4-bisanilinopyridine (BAPyd) libraries

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.     

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.     

Chemistry of heterocyclic compounds at the A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences, over 50 years (Review)

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.     

Sulfur-directed metal-free and regiospecific methyl C(sp3)–H imidation of thioanisoles

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.     

Selective syntheses of 2H-1,3-oxazines and 1H-pyrrol-3(2H)-ones via temperature-dependent Rh(II)-carbenoid-mediated 2H-azirine-ring expansion

The Rh(II)-catalyzed reaction of 2-carbonyl-substituted 2H-azirines with ethyl 2-cyano-2-diazoacetate or 2-diazo-3,3,3-trifluoropropionate provides an easy access to 2H-1,3-oxazines and 1H-pyrrol-3(2H)-ones. These compounds can be selectively prepared from the same starting material using temperature as the only varied parameter. The 2-azabuta-1,3-diene intermediate, a common precursor for both heterocyclic products, isomerizes into 2H-1,3-oxazine under kinetic control, while 1H-pyrrol-3(2H)-one is the sole product of the reaction at elevated temperatures. According to DFT-calculations a one-atom oxazine ring contraction involving ring-opening to a 2-azabuta-1,3-diene intermediate, followed by a 1,5- and 1,2-prototropic shift leads to the consecutive formation of imidoylketene and azomethine ylide, which then further undergo cyclization to the pyrrole derivative.     

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.