酶功能化聚多巴胺包覆纳米普鲁士蓝的制备及电化学分析应用

在纳米金表面原位沉积普鲁士蓝,然后在核壳结构纳米金-普鲁士蓝的表面包覆一层易氧化聚合的多巴胺保护膜,利用多巴胺聚合表面残留的大量氨基和羟基进一步将纳米铂粒子修饰于聚多巴胺膜表面制得普鲁士蓝-聚多巴胺-纳米铂多层纳米复合材料。将此复合材料修饰于金电极表面,协同使用辣根过氧化物酶用于H_2O_2浓度的检测。结果表明:聚多巴胺的引入有效增加了普鲁士蓝的稳定性,增大了纳米铂的负载量以及辣根过氧化物酶的生物活性;由于普鲁士蓝、纳米铂和辣根过氧化物酶的多重信号放大作用,酶功能化纳米复合材料修饰电极对H_2O_2表现出良好的电还原活性。优化条件下,对H_2O_2的检测范围为2.0×10~(-7)~1.0×10~(-3)mol·L~(-1),检出限(S/N=3)为1.2×10~(-7)mol·L~(-1)。     

掺杂纳米普鲁士蓝溶胶-凝胶修饰葡萄糖生物传感器

采用溶胶-凝胶法制备了纳米普鲁士蓝微粒,将含纳米普鲁士蓝微粒的TiO2溶胶-凝胶固定在玻碳电极表面得到纳米普鲁士蓝修饰电极,该电极对H2O2产生灵敏的响应,线性范围为0．5～400μmoL／L,较常规普鲁士蓝修饰电极(线性范围为25～500μmol／L)灵敏。电极表面再用溶胶．凝胶法固定葡萄糖氧化酶后构建了葡萄糖生物传感器,响应范围0～20mmoL／L,葡萄糖氧化酶表观米氏常数为8．04mmoL／L。实验表明,该法适合于批量制作高灵敏和高重现性的生物传感器。     

不同形貌普鲁士蓝纳米粒子的合成及光热性能

制备了立方体、直角立方体、球形、棒状、中空状、核壳状、梭形、多面体等8种不同形貌的普鲁士蓝纳米粒子,利用扫描电子显微镜、透射电子显微镜、紫外-可见分光光度计等对纳米粒子进行了表征,考察了普鲁士蓝纳米粒子光热性能的影响因素.结果表明,普鲁士蓝纳米粒子的形貌与光热性能之间联系密切,粒子形貌不同,光热性能不同;当外部实验条件一定时,纳米粒子的形貌、大小、吸收横截面积、尖锐化程度及密实程度等对其光热性能有很大的影响;当纳米粒子形貌一定时,外部因素如激光器的选择、激光功率密度及纳米粒子的浓度等直接影响普鲁士蓝纳米粒子的光热性能;在相同浓度下,激光功率密度越大,纳米粒子的升温效果越明显,光热性能越好;而激光功率密度不变时,纳米粒子浓度越大,其光热转换效率越高.     

普鲁士蓝纳米修饰电极的制备及表征

采用激光加热拉伸的方法制备铂纳米电极,并通过交流电刻蚀的方法制备纳米孔电极,在这两种电极上可通过电化学方法原位合成单颗普鲁士蓝微晶. 结果表明,普鲁士蓝微晶在纳米微孔电极上的机械附着强度增强. 这种方法可用于制备纳米修饰电极或研究功能微晶体材料的电化学性质.     

普鲁士蓝薄膜的电化学制备及其光电性质研究

在创新教育背景下,设计普鲁士蓝薄膜合成及其光电性质研究的教学实验,将科学研究成果引入大学综合实验中。采用简单电化学沉积法,在ITO导电玻璃表面制备得到普鲁士蓝膜,利用扫描电子显微镜、X射线衍射、循环伏安法、紫外-可见吸收光谱等研究普鲁士蓝薄膜的物理化学性质。基于大学生在化学实验中已掌握的实验技能,结合已有的电化学综合实验,设计搭建原位紫外-可见光谱电化学及光电流测试平台。通过具体的实验操作,在了解普鲁士蓝与普鲁士白等相互转化原理的基础上,进一步认识普鲁士蓝电致变色现象及光电流产生的过程,以此激发学生对光电化学实验的兴趣,有助于学生科学发散思维的拓展和实验技能的提高。     

普鲁士蓝在化学传感器中的研究及应用

综述了普鲁士蓝化学传感器的研究和应用进展。介绍了传感器敏感膜的制备方法，在电化学传感器和光学传感器中的应用及机理研究方面的成果。普鲁士蓝优越的氧化还原性质使普鲁士蓝化学传感器对于许多物质的检测有着重要的意义。     

类普鲁士蓝纳米酶材料的制备及其酶催化反应动力学探究——推荐一个分析化学综合实验

将类普鲁士蓝纳米酶引入本科实验教学，设计了一个探究性的分析化学综合实验，实验内容包括三种类普鲁士蓝纳米酶材料的制备、表征和酶催化反应速率常数的测定，并将这些纳米酶材料应用于过氧化氢(H₂O₂)的分析检测。本实验所用试剂价廉易得、反应条件温和、实验现象直观、时间分配合理，适合本科实验教学，用于提升学生的实验技能和科研创新能力。     

电化学制备普鲁士蓝-石墨烯复合物及对过氧化氢电催化性能研究

通过电化学方法制备了普鲁士蓝-石墨烯复合物,利用扫描电子显微镜(SEM)技术表征了石墨烯及石墨烯复合物的形貌结构特征。选取H2O2作为探针分子,采用电化学技术考察了普鲁士蓝-石墨烯复合物对的电催化性能。复合物修饰电极对H2O2具有良好的电催化还原活性,增强的催化活性可能与石墨烯与普鲁士蓝纳米颗粒之间的协同效应有关。复合物电极材料能够实现对H2O2的快速、灵敏检测,有望用作检测H2O2的传感平台。     

基于普鲁士蓝电催化的三维多孔壳聚糖膜葡萄糖生物传感器的研制

利用电沉积方法对普鲁士蓝和壳聚糖/SiO2纳米粒子复合膜进行组装,用刻蚀法除去SiO2粒子,制备出孔径大小均匀的多孔壳聚糖/普鲁士蓝膜,这种三维多孔膜具有良好的微生物环境、比表面积大、孔隙率高,有利于负载更多的葡萄糖氧化酶,从而构建了一种灵敏度高、稳定性好、响应时间短、检测范围宽的葡萄糖生物传感器。     

普鲁士蓝/CdS纳米复合物电致化学发光及其H2O2传感应用

通过一定体积比的CdS和普鲁士蓝(PB)胶体纳米溶液的简单混合,制备了PB/CdS纳米复合物。在共反应剂存在条件下,PB纳米粒子含量较低时,在ITO电极上CdS纳晶的电致化学发光(ECL)强度可以增强3倍左右。PB纳米粒子含量较高时,CdS纳晶的ECL强度则显著降低。详细讨论了PB纳米粒子对CdS纳晶ECL影响的机理。PB纳米粒子对CdS纳晶的ECL增强可用于H2O2传感。该传感器对H2O2响应的线性范围为3.3×10-8～6.5×10-3 mol.L-1(R=0.999 2),检测限为12 nmol.L-1(S/N=3),传感器具有良好的稳定性和重现性。     

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.     

N-Heterocyclic carbene-palladacyclic complexes: synthesis,characterization and their applications in the C-N coupling and α-arylation of ketones using aryl chlorides

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%).     

Iodine-mediated oxidative Pictet-Spengler reaction using terminal alkyne as the 2-oxoaldehyde surrogate for the synthesis of 1-aroyl-β-carbolines and fused-nitrogen heterocycles

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.     

Facile synthesis of bicyclic 1-arylpyrazol-5-ones

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.     

Synthesis of pyrrolo[1,2-a]pyrazines and pyrazino[1,2-a]indoles by Curtius reaction in Morita-Baylis-Hillman derivatives

Synthesis of substituted pyrrolo[1,2-a]pyrazines and pyrazino[1,2-a]indoles from the Morita-Baylis-Hillman derivatives of acrylates via saponification followed by Curtius reaction is described.     

正丁胺对激光染料荧光谱影响的研究

用正丁胺作为碳源,采用射频辉光放电制备碳膜,选用激光染料R6G和聚乙二醇混合液作为蒸气源,采用单源热蒸发,在蒸发室与染料同时沉积得到混合膜,用拉曼光谱和红外光谱分析了碳膜的结构和键合方式,分析表明:碳膜中存在胺基团和氢原子.混合膜的荧光谱测量结果表明,认为正丁胺对染料荧光谱的影响是因为胺基和氢原子的存在.     

Cu0-catalysed 1,3-dipolar cycloadditions of α-amino acid derived N,N-cyclic azomethine imines to ynones

A series of 20 CuAIAC reactions between eight 4-acylamino substituted pyrazolidine-3-one-1-azomethine imines and four terminal ynones were performed using Cu⁰ as catalyst. The corresponding fluorescent cycloadducts were obtained in very high yields upon simple workup. Thus, Cu-metal turned out to be a better catalyst than Cu^I in terms of yield and ease of isolation. Availability of azomethine imines, mild reaction conditions, and simple workup enable a “click” access to libraries of densely substituted 2,3-dihydro-1H,5H-pyrazolo[1,2-a]pyrazol-1-ones. Reactivity of differently substituted dipoles was evaluated experimentally and by quantum chemical methods (DFT).     

Synthesis and antioxidative/anti-inflammatory activity of novel fullerene–polyamine conjugates

(E)-4-(Fullerenopyrrolidin-1-yl)-3-methylbut-2-enoic acid and its corresponding succinimidyl ester, readily obtained through Prato-type modification of C₆₀, were used for the selective N-acylation of polyamines. The thus obtained conjugates were evaluated for their antioxidative and anti-inflammatory activity and their cytotoxicity was determined. Members of this family of compounds showed interesting anti-lipid peroxidation, anti-lipoxygenase and anti-inflammatory activity and comparable cytocompatibility to spermidine.