A Novel Sensitive Biosensor for Ca2+ Ion Based on Gold Nanoparticles Modified Electrode by Pulsed Electrodeposition

The work demonstrates a simple method for sensitive detection of Ca²⁺ ion by electrochemical response of alizarin red S (ARS) and Ca-ARS at a gold nanoparticle modified glassy carbon electrode (GCE). In the 0.1 M KOH, a sensitive reduction peak was observed at ?0.795 V at the gold nanoparticles modified electrode. The peak currents were proportional to the concentrations of Ca²⁺ ion in the range of 2.0 × 10^?7 M–1.2 × 10^?4 M. For the different pulse voltammetry (DPV) methods, the detection limit was 2.57 × 10^?8 M. The reaction mechanism was primarily determined by cyclic voltammetry, and the experimental results showed that the electrode processes were quasireversible responses of ARS and irreversible responses of ARS-Ca. In addition, the method was simple, fast, precise, and was used in the determination of calcium in blood serum with satisfactory results.     

一种比率型Cu~(2+)电化学传感器及其分析应用

本研究以硫堇聚合物作为内参比探针分子,通过电化学聚合法将硫堇聚合于单壁碳纳米管修饰玻碳电极(SWNTs/GCE)上,并以该修饰电极为工作电极,建立了一种比率型检测Cu~(2+)的电化学传感方法。结果表明,在1~25μmol/L浓度范围内,Cu~(2+)的阳极溶出峰电流ICu~(2+)与聚硫堇氧化峰电流ITh的比值与Cu~(2+)浓度呈较好的线性关系,检测限为96nmol/L,方法用于加标自来水样中Cu~(2+)的检测,回收率较好。     

An Electrochemical Sensor for the Detection of Cu2+ Based on Gold Nanoflowers‐modifed Electrode and DNAzyme Functionalized Au@MIL‐101 (Fe)

In this study, we developed an electrochemical sensor for sensitive detection of Cu²⁺ based on gold nanoflowers (AuNFs)‐modified electrode and DNAzyme functionalized Au@MIL‐101(Fe) (MIL: Materials of Institute Lavoisier). The AuNFs‐modified indium tin oxide modified conductive glass electrode(AuNFs/ITO) prepared via electrodeposition showed improved electronic transport properties and provided more active sites to adsorb large amounts of oligonucleotide substrate (DNA1) via thiol‐gold bonds. The stable Au@MIL‐101(Fe) could guarantee the sensitivity because of its intrinsic peroxidase mimic property, while the Cu²⁺‐dependent DNA‐cleaving DNAzyme linked to Au@MIL‐101(Fe) achieved the selectivity toward Cu²⁺. After the DNAzyme substrate strand (DNA2) was cleaved into two parts due to the presence of Cu²⁺, the oligonucleotide fragment linked to MIL‐101(Fe) was able to hybridize with DNA1 adsorbed onto the surface of AuNFs/ITO. Due to the peroxidase‐like catalytic activity of MIL‐101(Fe) and the affinity recognition property of DNAzyme toward Cu²⁺, the electrochemical biosensor showed a sensitive detection range from 0.001 to 100 μM, a detection limit of 0.457 nM and a high selectivity, demonstrating its potential for Cu²⁺ detection in real environmental samples.     

高灵敏比色检测Cu~(2+)的反蛋白石结构光子晶体水凝胶膜

以丙烯酰胺(AM)和N-乙烯基咪唑(NVI)为双功能单体,借助"三明治"结构有效控制前驱液的填充,制备了可特异性识别Cu~(2+)的反蛋白石结构光子晶体水凝胶膜(PCHs).该PCHs具有相互贯通的三维有序大孔结构,可在Cu~(2+)缓冲溶液中快速响应,产生特征的布拉格(Bragg)衍射峰.随着Cu~(2+)浓度的增大(0~10-4mol/L),PCHs的Bragg衍射峰位移66 nm,并伴随着明显的颜色变化(由棕红色逐渐变为黄绿色).此外,PCHs在混合金属盐溶液中仍能实现对Cu~(2+)的特异性识别.PCHs对Cu~(2+)的特异识别性、快速响应及自表达的特点为Cu~(2+)现场快速检测提供了可能.     

Tb~(3+)配合物修饰的磁性纳米荧光探针对水中Cu~(2+)的超灵敏检测

合成了一种Tb~(3+)配合物修饰的磁性纳米荧光探针cs124-DTPA-NH-PEGDBI-Fe3O4∶Tb。该复合荧光探针与Cu~(2+)有很强的结合能力,Cu~(2+)对Tb~(3+)配合物修饰的磁性纳米荧光探针具有荧光猝灭作用。实验表明,该复合荧光探针稳定性良好且有很好的水溶性,可在较宽的pH范围(5.0~10.0)快速检测Cu~(2+)。此外,在竞争实验中发现,该纳米荧光探针能够实现对溶液中Cu~(2+)的超灵敏和选择性检测而对其他多种常见离子响应较小,对Cu~(2+)的检测限甚至可达到1nmol/L。     

Syntheses,structures of N‐(substituted)‐2‐aza‐[3]‐ferrocenophanes and their application as redox sensor for Cu2+ ion

Rigid N‐(substituted)‐2‐aza‐[3]‐ferrocenophanes L1 and L2 were easily synthesized from 1,1 ‐dicarboxyaldehydeferrocene and the corresponding amines. Ligands L1 and L2 were characterized by ¹H NMR, ¹³C NMR and single‐crystal X‐ray crystallography. The coordination abilities of L1 and L2 with metal ions such as Cu²⁺, Mg²⁺, Ni²⁺, Zn²⁺, Pb²⁺ and Cd²⁺ were evaluated by cyclic voltammetry. The electrochemical shift (ΔE_1/2) of 125 mV was observed in the presence of Cu²⁺ ion, while no significant shift of the Fc/Fc + couple was observed when Mg²⁺, Ni²⁺, Zn²⁺, Pb²⁺, Cd²⁺ metal ions were added to the solution of L1 in the mixture of MeOH and H₂O. Moreover, the extent of the anodic shift of redox potentials was approximately equal to that induced by Cu²⁺ alone when a mixture of Cu²⁺, Mg²⁺, Ni²⁺, Zn²⁺, Pb²⁺ and Cd²⁺ was added to a solution of L1. Ligand L1 was proved to selectively sense Cu²⁺ in the presence of large, excessive first‐row transition and late‐transition metal cations. The coordination model was proposed from the results of controlled experiments and quantum calculations. Copyright © 2012 John Wiley & Sons, Ltd.     

胡椒碱与牛血清白蛋白的作用及Cu2+、Fe3+影响的研究

采用荧光光谱及紫外光谱法研究了胡椒碱与牛血清白蛋白（bovine serum albumin,BSA）的相互作用。实验结果表明：胡椒碱与BSA形成基态复合物从而猝灭BSA的内源性荧光,猝灭原因主要为静态猝灭和非辐射能量转移作用。胡椒碱对BSA的猝灭速率常数Kq为7．31×10^12 L·mol^-1·s^-1（25℃）和7．20×10^12 L·mol^-1·s^-1（37℃）,胡椒碱与BSA的结合常数K为1．02×10^7 L·mol^-1（25℃）和1．11×10^7 L·mol^-1（37℃）,结合位点数n为1．45（25℃）和1．46（37℃）。根据Ftirster偶极-偶极非辐射能量转移理论问题得到结合距离r为3．28nm（25℃）和3．30nm（37℃）。通过热力学参数的计算,确定胡椒碱与牛血清白蛋白的相互作用是一个熵增加和吉布斯自由能降低的自发过程,主要作用力为疏水作用力。同步荧光光谱表明,胡椒碱与BSA的相互作用没有引起BSA构象的变化。讨论了共存金属离子Cu^2＋、Fe^3＋对胡椒碱与BSA相互作用的影响。     

电沉积法制备石墨烯纸-金属复合材料的初步研究

石墨烯纸具有优良的导电导热性能,但强度和硬度较低。为了获得良好的综合力学性能以提高石墨烯纸的实用价值,本文提出了制备石墨烯纸-金属复合材料的构想,从实验上初步研究了电沉积法制备石墨烯纸-金属复合材料的可行性,并探究了石墨烯纸与电沉积金属界面结合情况。采用两种常见镀层金属Cu、Cr,在实验室使用电沉积法制备了石墨烯纸-Cu,石墨烯纸-Cr两种复合镀层材料。利用扫描电镜对复合材料的表面形貌和横截面进行了表征,结果显示石墨烯纸-Cr复合材料的界面结合相对紧密。本文首次将二维错配度应用到石墨烯纸与金属镀层界面结合力分析中,通过计算分析,常温下C 的（0001）面与Cr的（110）面的二维错配度为7.26%,晶格匹配度良好. 随温度升高,C-Cr界面错配度值减小,即晶格匹配度增加,另外C-Cr二元相图显示C与Cr发生反应生成的碳化物将进一步增强其界面结合。     

Cu2+‐doped ITO as a Novel Efficient,Transparent, and Fast‐Response Transducer for Ammonia Sensing

As a novel approach, the effect of Cu²⁺‐doped indium tin oxide (ITO) on a flexible polycarbonate substrate is considered as an ammonia sensor. The sensor was fabricated using spin‐coating and subsequent annealing at 160°C for 60 min. The constructed sensor morphology accomplished by surface composition was explored using scanning electron microscopy (SEM) and energy dispersiveX‐ray (EDX) spectroscopy. Using the new strategy, a flexible sensor for ammonia determination with a fast response time of less than 7 s and a recovery time of 8 s was achieved. Sensor characteristics, such as sensitivity, recyclability, response/recovery time, selectivity, stability, flexibility, and transmittance of the layers, were examined. The impedance results showed high sensitivity when the constructed sensor was exposed to NH₃ concentrations in the range 5–1000 ppm. The results showed that doping ITO with Cu²⁺ imparted higher electronic charge density to the sensor surface and enhanced the sensitivity of the sensor by a factor of 352% in comparison with that of pure ITO. The sensitivity, fast response, and recovery time with low‐cost materials and deposition procedure suggest an effective and disposable ammonia sensor at room temperature (23°C).     

Application of Luminescent BSA‐Capped CdS Quantum Dots as a Fluorescence Probe for the Detection of Cu2+

CdS Quantum dots (QDs) are synthesized in aqueous solution with bovine serum albumin (BSA) as the stabilizing agents using a stepwise procedure at room temperature. They can be used as a new fluorescence probe in the determination of Cu²⁺, which is proved to be a simple, rapid and specific method. Approximate concentrations of other physiologically important cations, such as Zn²⁺, K⁺ etc, have no effect on the fluorescence. Under the optimum condition, the response is linear to the concentration of Cu²⁺ in the range of 0‐80.0 μol/L, and the detection limit is 50.0 nmol/L. This method is used to the determination of Cu²⁺ in human hair, the recovery is 98‐104%. And the possible detection mechanism is also discussed.     

NO在铜离子交换型沸石上的分解

ＮＯ在铜离子交换型沸石上的催化分解＊韩一帆汪仁（华东理工大学工业催化研究所，上海２００２３７）关键词一氧化氮，催化分解，铜离子交换型沸石随着工业生产的发展和机动车辆的增加，向大气中排放的含氮氧化物（ＮＯｘ）的量日益增多．如何降低大气中ＮＯｘ的浓度，减...     

水溶液中Cu^2＋,Zn^2＋双组分金属离子与胆固醇的相互作用

水溶液中Ｃｕ２＋、Ｚｎ２＋双组分金属离子与胆固醇的相互作用宋仲容（重庆高等师范专科学校化学系永川４０２１６８）李树伟（四川师范大学化学系成都６１００６６）关键词Ｃｕ２＋Ｚｎ２＋胆固醇吸附中国分类号Ｏ６１１．３铜锌金属离子在冠心病的发生与发展中有着重要...     

提取腐植酸后的残渣对Cu~(2+)的吸附性能研究

研究了天祝褐煤中提取腐植酸后的残渣对Cu2+的吸附性能。结果表明,在室温(20～25℃)条件下,吸附平衡时间约为5h,吸附最佳pH为5～6,相关系数R为0.9889,特性常数n为3.449。吸附符合Freundfich吸附等温式,提取腐植酸后的残渣对Cu2+有较好的吸附性能,其吸附过程可用Ho准二级反应动力学模型描述。     

方波脉冲法制备Cu_2O@Cu/TiO_2三维阵列纳米复合材料及其作为高灵敏无酶型葡萄糖传感器的研究

采用阳极氧化法制备了TiO_2三维阵列纳米管(TiO_2 NTAs),再利用方波脉冲法在TiO_2 NTAs表面电沉积Cu薄膜,经过煅烧处理后得到Cu_2O@Cu/TiO_2 NTAs纳米复合材料。X-射线衍射仪(XRD)测试表明该材料中Cu和Cu_2O共存。扫描电镜(SEM)和透射电镜(TEM)分析显示,TiO_2管壁的外表面均匀生长Cu_2O,选区电子衍射结果表明该纳米复合材料为混晶材料。差分脉冲伏安法表明,Cu_2O@Cu/TiO_2 NTAs在+0.56 V处出现明显的葡萄糖氧化峰,表明该纳米复合材料对葡萄糖具有强的电催化作用,可用于葡萄糖的测定。计时电流法得到葡萄糖的线性范围为0.19～3.5 mmol/L,灵敏度为372.0μA·L·mmol~(-1)·cm~(-2),检出限为3μmol/L。交流阻抗测得Cu_2O/TiO_2 NTAs的传荷阻抗为526.2Ω,Cu_2O@Cu/TiO_2 NTAs为1.8Ω,二者相差292倍,说明Cu作为中间过渡层降低了电子传导的传荷阻抗。将该电极用于血清中葡萄糖含量的检测,测试结果与医院测定结果无显著差异。Cu_2O@Cu/TiO_2 NTAs可作为一种灵敏度高、响应速度快、选择性较好的无酶型葡萄糖传感器。     

三聚硫氰酸交联聚氯乙烯树脂的合成及其对Cu~(2+)的吸附性能

以三聚硫氰酸为原料,邻苯二甲酸二辛酯(DOP)为增塑剂,聚氯乙烯为大分子骨架,在MgO的存在下,合成得到了三聚硫氰酸交联聚氯乙烯树脂.对交联树脂吸附重金属离子的性能研究表明,合成树脂对Cu2+的吸附容量及选择性最大,在实验条件下吸附量达到1.056mmol/g;对其他金属离子吸附量很小,甚至不吸附.     

One‐Pot Synthesis of Carbon‐Coated Nanostructured Iron Oxide on Few‐Layer Graphene for Lithium‐Ion Batteries

Nanostructure engineering has been demonstrated to improve the electrochemical performance of iron oxide based electrodes in Li‐ion batteries (LIBs). However, the synthesis of advanced functional materials often requires multiple steps. Herein, we present a facile one‐pot synthesis of carbon‐coated nanostructured iron oxide on few‐layer graphene through high‐pressure pyrolysis of ferrocene in the presence of pristine graphene. The ferrocene precursor supplies both iron and carbon to form the carbon‐coated iron oxide, while the graphene acts as a high‐surface‐area anchor to achieve small metal oxide nanoparticles. When evaluated as a negative‐electrode material for LIBs, our composite showed improved electrochemical performance compared to commercial iron oxide nanopowders, especially at fast charge/discharge rates.     

Comparative Studies of Some Novel Cu2+ and Fe3+ Chelates Derived From Tricine (L1) by Single Crystal X‐ray,Spectroscopic and Biological Data: Applications to Investigate Antitumor Activity

Novel Cu ²⁺ and Fe ³⁺ chelates derived from L ¹ were synthesized and characterized by single crystal X‐ray diffraction. The results indicate that the Fe (III) crystal, [Fe(L¹‐H)Cl₂], has an orthorhombic structure of the type pc2b while the dimeric Cu (II) crystal, [Cu(L¹‐H)Cl … ClCu(L¹‐H)], has a monoclinic with space group Cc. X‐ray diffraction and spectroscopic studies revealed that L ¹ acts as monobasic tetradentate with octahedral geometry in Fe (III) crystal while it behaves as dibasic tetradentate with distorted‐octahedral in the Cu (II) crystal. Also, the two chelates were characterized by spectral, magnetic and thermal analyses. DFT parameters were used to prove the liberation of a proton from COOH rather than NH groups. The kinetic and thermodynamic parameters of Fe (III) chelate were determined by Coats‐Redfern and Horowitz‐Metzger methods. Cyclic voltammogram provides information about the oxidation states of Cu (II) and Fe (III) chelates. Antitumor activity against Epitheliod carcinoma (Hela), breast cancer (MCF‐7) and antibacterial activities of chelates were investigated.     

新型水溶性中氮茚衍生物的合成及铜离子荧光探针行为

设计合成了2个新型水溶性中氮茚季铵盐化合物4a{氯化2-[N'-(3-氰基-中氮茚-1-甲酰基)肼基]酰乙基-1-吡啶鎓盐}和4b{氯化2-[N'-(3-氰基-中氮茚-1-甲酰基)肼基]酰乙基-1-(2-甲基吡啶)鎓盐},采用红外光谱、核磁共振、质谱和元素分析对其进行了结构表征,并研究了它们的光谱性质.选取Cu2+,Zn2+,Ca2+,Cr3+,Co2+,Al3+,Mn2+,Ni2+,Ba2+,Hg2+,Fe3+,Cd2+,Mg2+,Pb2+,Li+和Ag+等16种常见金属离子,对2个化合物进行了离子识别实验.结果表明,化合物4a和4b在一定浓度范围内对铜离子均具有良好的选择性识别能力,受常见离子干扰小.由于空间位阻的影响,化合物4a具有比4b更高的灵敏性.