基于Ru(bpy)■-三乙胺体系的电致化学发光生物传感器检测葡萄糖

联吡啶钌(Ru(bpy)■)拥有优良的电致化学发光(ECL)性能,但其较好的水溶性使其固载面临巨大问题。该文制备了Pt纳米粒子与Ru(bpy)■的复合物(Pt NPs-Ru),将其修饰于电极并进一步固载葡萄糖氧化酶(GOx)制得传感器。基于H2O2对Ru(bpy)■-三乙胺体系ECL信号的猝灭作用,随着葡萄糖浓度的增加,其在GOx的催化下原位产生的H2O2量增多,导致ECL信号逐渐减弱,从而实现葡萄糖的检测。ECL强度与葡萄糖浓度的对数在1.0×10-8~5.0×10-5 mol/L范围内呈良好的线性关系,检出限低至5.2×10-9 mol/L。传感器具有好的稳定性和高的选择性。Pt NPs-Ru复合物为ECL传感器的构建提供了良好平台,为葡萄糖检测提供了新方法。     

基于铱纳米棒的电致化学发光生物传感器用于多巴胺检测

铱(Ⅲ)配合物差的水溶性限制了其在电致化学发光(ECL)领域的应用。该文用聚(苯乙烯-马来酸酐)(PSMA)羧基功能化三(2.苯基吡啶)铱(Ⅲ)(Ir(ppy)3)合成水溶性铱纳米棒(Ir NDs)。在共反应试剂三丙胺(TPrA)存在下,Ir NDs 表现出优良的ECL性能。借助多巴胺(DA)对Ir NDs-TPrA体系ECL的高效猝灭作用,实现了对DA的高灵敏检测,线性范围为2.0×10-8~4.0×10-4 mol/L,检出限为6.3×10-9 mol/L。羧基功能化的Ir NDs为铱(Ⅲ)配合物在ECL领域的应用提供了理想平台,也为DA的检测提供了新方法。     

高灵敏ECL－RET传感器的构建及其用于血清前列腺特异性抗原检测的研究

肿瘤标志物在癌症早期诊断与预后监测中具有非常重要意义。前列腺癌作为男性泌尿生殖系统中最常见的恶性肿瘤,其血清前列腺特异性抗原（PSA）是最重要的早期检测指标。该研究以制备的四元Cu－Zn－In－S纳米晶（NCs）作为发光体,金纳米星（AuNSs）作为猝灭探针,利用K2S2O8作为共反应剂,发展了一种基于量子点电化学发光共振能量转移的免疫传感器（ECL－RET）用于血清中PSA的高灵敏检测。固定在传感器上的NCs表现出极强的初始ECL信号和较低的ECL电位。作为固定基底的多壁碳纳米管（MWNTs）不仅加速了NCs与S2O2?8之间的反应,获得了较高的ECL信号,而且作为载体可以固定大量的抗体,提高传感器检测PSA的灵敏度。采用电化学交流阻抗法（EIS）对组装过程进行跟踪,证实了该传感器组装的可行性。采用电化学发光法研究了传感器对底液中不同浓度PSA的响应,结果显示,随着体系中PSA浓度的增加,电极上结合AuNSs的标记抗体（Ab2－AuNSs）越多,触发的猝灭效果越明显,ECL信号降低越明显。因此,该传感器表现出对PSA较好的分析性能,其线性范围为0.01～150 ng/mL,检出限为0.03 ng/mL。用于血清样品的检测,该传感器的测试结果与常用的化学发光法基本吻合,相对误差仅为-7.2%～6.0%,结果准确度良好,为临床检测PSA提供了准确可靠的新方法。     

二氧化硅纳米颗粒表面原位还原银纳米簇电化学发光传感界面的构建与分子识别

通过牛血清蛋白(BSA)对二氧化硅纳米颗粒(SiO₂ NPs)表面进行氨基、 巯基功能化, 随后以BSA同时作为模板和还原剂, 原位生成银纳米簇(Ag NCs), 获得显著增强阴极电化学发光(ECL)信号的Ag NCs-SiO₂ NPs复合纳米材料. 结果表明, 当测试溶液中含有L-半胱氨酸(L-Cys)时, 其与传感界面上的Ag NCs发生共价结合作用, 从而猝灭其ECL信号. 基于该原理, 构建了“开-关”型ECL信号响应模式的L-Cys生物传感器. 该传感器检测L-Cys的浓度范围为50 nmol/L~50 μmol/L, 最低检测限达到13.7 nmol/L, 能够实现L-Cys的高灵敏及特异性分析, 有望在生物、 医学等领域得到广泛应用.     

猝灭-恢复型电化学发光传感器测定抗坏血酸的研究

制备了氮硫掺杂石墨烯量子点(NSGQDs),并将其修饰在金电极表面.基于NSGQDs良好的电化学发光(ECL)特性,以其为探针,进一步将铜-金属有机框架(Cu-MOF)修饰于该电极表面,构建了猝灭-恢复型ECL传感器用于抗坏血酸的高灵敏检测.由于NSGQDs表面存在大量氨基,当Cu-MOF存在时,NSGQDs的ECL信号猝灭;加入抗坏血酸后,Cu-MOF从NSGQDs表面自动脱落,NSGQDs的ECL信号得以恢复.NSGQDs的ECL信号恢复值与抗坏血酸浓度在0.1～40 μmol/L之间呈良好的线性关系,检出限为3.2 nmol/L.该法已用于血样中抗坏血酸的测定,并进一步研究了人血液中抗坏血酸24h的药代动力学规律.     

以Pt/COF-LZUI为固定基底和Pd NPs/MnO_2为标记物的C反应蛋白免疫传感器的研制

采用溶剂热法合成了共价有机框架材料,并使铂(Ⅳ)通过电化学还原沉积于此材料上,制成作为固定化基质的Pt/COF-LZUI。另据文献分别制备了MnO_2纳米材料,Pd NPs/MnO_2纳米复合材料,及以此为标记物的CRP抗体。用上述材料按规定程序修饰玻碳电极并制成夹心型CRP免疫传感器。利用固体核磁、X射线粉末衍射对COF-LZUI的结构和晶型结构进行了表征,利用透射电镜对COF-LZUl、Pt/COF-LZUl和Pd NPs/MnO_2纳米复合材料的形貌进行了表征。采用循环伏安法和计时电流法(i-t)研究该传感器的电化学特性及该电极对过氧化氢的电化学响应。该传感器的线性范围为1~150μg·L-1,检出限(3σ)为0.33μg·L~(-1)。     

基于Ru(bpy)■-三乙胺体系的电致化学发光生物传感器检测葡萄糖

联吡啶钌(Ru(bpy)■)拥有优良的电致化学发光(ECL)性能,但其较好的水溶性使其固载面临巨大问题。该文制备了Pt纳米粒子与Ru(bpy)■的复合物(Pt NPs-Ru),将其修饰于电极并进一步固载葡萄糖氧化酶(GOx)制得传感器。基于H_2O_2对Ru(bpy)■-三乙胺体系ECL信号的猝灭作用,随着葡萄糖浓度的增加,其在GOx的催化下原位产生的H_2O_2量增多,导致ECL信号逐渐减弱,从而实现葡萄糖的检测。ECL强度与葡萄糖浓度的对数在1.0×10~(-8)～5.0×10~(-5) mol/L范围内呈良好的线性关系,检出限低至5.2×10~(-9) mol/L。传感器具有好的稳定性和高的选择性。Pt NPs-Ru复合物为ECL传感器的构建提供了良好平台,为葡萄糖检测提供了新方法。     

基于聚合物点的电致化学发光生物传感器用于葡萄糖检测

羧基功能化的聚[(9,9-二辛基芴基-2,7-二基)-co-(1,4-苯并-{2,1′,3}-噻二唑)]聚合物点(PFBT-COOH)在无外加共反应试剂的条件下具有高的电致化学发光(ECL)信号,且过氧化氢(H_2O_2)对其ECL具有高效猝灭作用。采用PFBT-COOH修饰玻碳电极,进一步交联葡萄糖氧化酶(GOD)以构建酶传感器(GOD/PFBT-COOH/GCE)。随着检测底液中葡萄糖浓度的增加,葡萄糖在GOD催化下原位产生的H_2O_2量增加,导致传感器的ECL信号逐渐减弱,从而实现葡萄糖的准确、快速、灵敏检测。此方法测得葡萄糖的线性范围为1.0×10~(-7)～3.0×10~(-3) mol/L,检出限为3.0×10~(-8) mol/L。血清样品中葡萄糖的加标回收率为98.5%～106%。该策略为酶传感器的构建提供了新思路,为葡萄糖的检测提供了新方法。     

二氧化锆/石墨烯复合材料对亚硝酸盐的电化学传感研究

制备了一种二氧化锆/还原氧化石墨烯(ZrO2NPs/rGO)复合材料修饰电极的亚硝酸盐电化学传感器,并成功用于亚硝酸盐的检测.采用循环伏安法和电流-时间曲线考察了修饰电极的电化学行为.实验结果表明,ZrO2NPs/rGO复合材料修饰电极对亚硝酸盐具有良好的电流响应.在最优实验条件下,电流-时间曲线中的电流响应信号与亚硝酸盐浓度在3.0×10Symbolm@@_7～1.0×10Symbolm@@_6 mol/L和1.0×10Symbolm@@_6～6.0×10Symbolm@@_6 mol/L的范围内呈良好的线性关系,检测限为1.0×10Symbolm@@_7 mol/L(S/N 3).该传感器灵敏性高、稳定性和重现性好.使用此传感器检测实际样品香肠中的亚硝酸盐的回收率为93.7％～110.4％,相对标准偏差为1.6％～2.1％.     

碳纳米管负载铂颗粒酶电极葡萄糖传感器

以碳纳米管负载纳米铂颗粒修饰玻碳电极 (CNT Pt/GCE)为基底 ,用明胶固定葡萄糖氧化酶(GOD) ,构建了电流型葡萄糖生物传感器 (GOD/CNT Pt/GCE)。在实验中 ,GOD/CNT Pt/GCE显示了良好的分析性能 ,与常规铂电极葡萄糖传感器 (GOD/Pt)相比较 ,测定葡萄糖的检出限从 6 .7× 10 -3 mol/L下降到8.3× 10 -4mol/L ;工作电位从 0 .6 5V下降至 0 .4 5V ;响应时间从 30s下降至 5s左右。实验结果表明 ,具有高度电催化活性的CNT Pt/GCE可作为酶传感器的一种新型基体电极。     

Fabrication of small-sized silver NPs/graphene sheets for high-quality surface-enhanced Raman scattering

In this paper, small-sized and highly dispersed Ag nanoparticles (NPs) supported on graphene nanosheets are fabricated via a strategy for etching a copper template with Ag(+). Firstly, big-sized Cu NPs are supported on graphene, and then the small-sized and highly dispersed Ag NPs are supported on graphene by replacement reaction, mainly making use of graphene passing electrons between Cu and Ag(+). The graphene used in the experiment is prepared by in situ self-generating template and has good dispersion, excellent crystallinity and little defects. Thus, in the process of Ag/graphene synthesis, there is no any intervention of surfactant, which ensures that SERS activity sites have not been passivated. And, the little defects of graphene benefit the excellent conductivity of graphene and ensured the replacement reaction between Cu and Ag(+). The obtained material exhibits significant high-quality and distinctive SERS activity. Especially, a serial new peak of p-aminothiophenol (PATP) is observed, this is suggested two reasons: one is "surface geometry" of the PATP on small-sized Ag NPs and another is the charge-transfer between Ag and graphene.     

Electrophoretic mobilities of PEGylated gold NPs

Electromigration of nanoparticles (NPs) is relevant to many technological and biological applications. We correlate the experimentally observed electromigration of Au NPs with a closed-form theoretical model that furnishes key NP characteristics, including the previously unknown values of Au NP core ζ-potential, PEG-corona permeability, and particle-hydrogel friction coefficient. More generally, the theory furnishes new understanding of NP electromigration in complex environments, establishing a robust and predictive model to guide the design and characterization of functionalized NPs.     

Cotton fabric incorporated with β-cyclodextrin/ketoconazole/Ag NPs generating outstanding antifungal and antibacterial performances

Cellulose - The influence of ketoconazole and β-CD/ketoconazole on cotton fabric as fungal skincare was previously reported however the impact of nanosilver on the antifungal and antibacterial...     

芦丁在铂纳米/碳纳米管修饰电极上电化学行为研究

通过电沉积的方式在多壁碳纳米管(MWCNTs)修饰玻碳电极表面上沉积铂(pt)纳米粒子,并运用循环伏安法(CV)、示差脉冲伏安法(DPV)探讨了芦丁在铂纳米/碳纳米管/玻碳电极上的电化学行为.实验结果表明,芦丁在该修饰电极上呈现一对良好氧化还原峰,其氧化峰电流与浓度在3.2×10(-8)～1.2×10(-5)mol/L...     

Preparation of Ligand Free Au NPs/PPV Composites with High Stability and Photo-electric Response

A novel kind of ligand free aurum nanoparticles(Au NPs)/poly(p-phenylene-vinylene)(PPV) composites was prepared via a simple approach. Although there were no ligands coating on the surface of the Au NPs, the Au NPs/PPV precursor composite exhibited excellent stability that no obvious variance was found as long as 6 months at ~4 ℃ in aqueous and alcohol mixed solutions. This was attributed to the strong interaction between Au NPs and PPV precursor, which was further strengthened after heat transformation. Fourier transform infrared(FTIR) and Raman spectra showed the interaction between benzene ring in PPV and Au NPs led to the part transformation of the sp2 hybrid orbital into the sp3 one during the composite formation. As a result, the photoluminescence(PL) life time of PPV in the composite was longer than that of pure PPV. The Au NPs/PPV composite exhibited good photo-electric response, indicating their potential application in the area of the photoelectric conversion devices.     

微波原位合成Ag NPs/MoS2复合材料及其电化学性能

二硫化钼纳米片（MoS₂）受到带电杂质、结构缺陷和易聚集等因素的影响，导致其电子转移性能下降，使其应用受限。将银纳米颗粒（Ag NPs）与少层MoS₂纳米片复合，可提升MoS₂纳米片的电化学性能。本研究创新性地采用微波还原法，使Ag NPs原位沉积于MoS₂，得到Ag NPs/MoS₂复合材料。结果表明，将Ag NPs/MoS₂复合材料修饰于丝网印刷电极（screen printed elec-trodes，SPE）后，测得的循环伏安（cyclic voltammetry，CV）曲线峰电流值为同浓度单一MoS₂修饰电极的1.8倍，方波伏安（square wave voltammetry，SWV）曲线峰电流值为单一MoS₂修饰电极的3.4倍，电化学阻抗谱（electrochemical impedance spectroscopy，EIS）的电子转移阻抗值（R_et）仅为167 Ω，相比MoS₂/SPE的R_et （320 Ω）显著减小，说明Ag NPs与MoS₂复合可显著增强单一MoS₂的电化学性能。此外，还推测了高导电性Ag NPs/MoS₂复合材料的导电机理。最后，基于Ag NPs/MoS₂复合材料构建了电化学传感器并对前列腺特异性抗原（PSA）进行检测。结果表明，该传感器针对PSA的检测限为0.009 ng·mL^-1，线性检测范围为0.1~1 000 ng·mL^-1，灵敏度为0.011 μA·mL·ng^-1。     

微波原位合成Ag NPs/MoS2复合材料及其电化学性能

二硫化钼纳米片(MoS₂)受到带电杂质、结构缺陷和易聚集等因素的影响,导致其电子转移性能下降,使其应用受限。将银纳米颗粒(Ag NPs)与少层MoS₂纳米片复合,可提升MoS₂纳米片的电化学性能。本研究创新性地采用微波还原法,使Ag NPs原位沉积于MoS₂,得到Ag NPs/MoS₂复合材料。结果表明,将Ag NPs/MoS₂复合材料修饰于丝网印刷电极(screen printed electrodes,SPE)后,测得的循环伏安(cyclic voltammetry,CV)曲线峰电流值为同浓度单一MoS₂修饰电极的1.8倍,方波伏安(square wave voltammetry,SWV)曲线峰电流值为单一MoS₂修饰电极的3.4倍,电化学阻抗谱(electrochemical impedance spectroscopy,EIS)的电子转移阻抗值(Ret)仅为167Ω,相比MoS₂/S...     

Electrochemical-reduction-assisted Assembly of Pd NPs/Polyoxometalates/Graphene Ternary Nanocomposite and Its Electrocatalytic Performance toward Formic Acid Oxidation

A novel ternary nanocomposite, Pd nanoparticles(NPs)/polyoxometalates(POMs)/reduced graphene oxide(rGO), was prepared by a green, mild, electrochemical-reductionassisted assembly. It is worth noting that the Keggin-type POM acts as an electrocatalyst as well as a bridging molecule. During the reduction process, POMs transfer the electrons from the electrode to GO, leading to a deep reduction of GO and the content of oxygen-containing groups is decreased to around 6.1%. Meanwhile, the strong adsorption effect between the POM clusters and rGO nanosheets induces the spontaneous assembly of POM on r GO in a uniformly dispersed state, forming a nanocomposite. The ternary Pd NPs/POMs/rGO nanocomposite exhibits higher electrocatalytic activities, better electrochemical stability, and higher resistance to CO poisoning than the Pd/C catalyst towards the formic acid oxidation(FAOR). Especially, the Pd/PW_(12)/rGO exhibits the best electrocatalytic performance among three Pd/POMs/rGO composites(POMs = PW_(12), SiW_(12), PMo_(12)).     

A green approach to prepare Ag NPs loaded IC/PVA polymeric film for antimicrobial applications

In this study, glyoxal-cross-linked Iota carrageenan (IC) /poly(vinyl alcohol) PVA films were prepared and loaded with silver nanoparticles via a green approach, consisting of sweet lime juice induced in-situ reduction of Ag(I) ions to nano silver within the film matrix. The formation of silver nanoparticles was confirmed using UV–visible spectrophotometry. The Ag NPs-loaded films were also characterized by X-ray diffraction (XRD), Scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR). The dynamic water uptake data were interpreted by the ‘Power functional model’. The films showed fair antimicrobial action against bacteria E. Coli.     

Z型可见光催化剂Au NPs/g-C3N4/BiOBr的构建及其光催化性能

通过水热和原位还原法制备了一种新型Z型异质结三元复合材料Au NPs/g-C₃N₄/BiOBr,并通过X射线衍射、X射线光电子能谱、透射电子显微镜、紫外-可见漫反射光谱和光致发光发射光谱等技术对材料的形貌、结构进行了表征。通过在可见光下降解苯酚来评价光催化剂的活性。研究发现,Au NPs/g-C₃N₄/BiOBr显示出增强的光催化活性,对苯酚的降解能力是g-C₃N₄的3倍,是BiOBr的2.5倍。这可归因于三元复合材料的窄带隙（2.10eV）、Z型机理对光生电子-空穴对的有效分离和Au纳米颗粒的表面等离子体共振效应（SPR）。