以多肽芯片为反应平台筛选激酶抑制剂

表面增强拉曼(SERS)技术是拉曼散射光与金属纳米粒子发生表面等离子共振而产生的拉曼增强现象,与荧光法相比,更适合做多通道检测并有助于提高选择性.近年来,SERS技术在生物分析等领域已经取得了重要研究进展,特别是以具有特征拉曼谱线的分子作为标记物标记DNA,RNA,蛋白质等生物分子,结合SERS检测高灵敏度的特点,使SERS技术在多通道免疫标记识别领域发挥重要的作用~([1,2]).     

细胞功能分子的表面增强拉曼成像及其应用研究进展

表面增强拉曼光谱(surface-enhanced Raman spectroscopy, SERS)具有高灵敏、高通量的特性.基于SERS的拉曼成像技术是一种无损的生物成像技术,已被广泛应用于细胞表面与细胞内生物分子的检测和成像,如对聚糖、microRNA、蛋白质等分子的定量、结构分析与功能追踪等.这一技术也已用于细菌的快速检测、细胞或细菌间的信号通讯研究、细胞p H检测,并可通过活体肿瘤组织的边缘描绘指导手术切除. SERS成像可以规避生命体系中强的分子自荧光以及荧光成像中的光漂白现象,并可以利用不同拉曼信标的指纹光谱实现高灵敏、高通量的生物成像.通过与其他成像技术(如核磁共振成像、光声成像)的结合, SERS成像有望用于更复杂生命体系中生物分子的研究.本文综述了近年来细胞功能分子的表面增强拉曼成像及其应用方面的研究进展.     

无机纳米-生物界面作用的SERS研究

探索生命体对无机纳米材料的生物应答机制是高效、安全、可控地应用无机纳米材料的基础,其关键在于准确理解在生物体系中无机纳米材料与生物分子间的纳米.生物界面作用.本文主要探讨了在纳米-生物界面具有拉曼增强效应的金、银纳米材料;介绍了表面增强拉曼光谱(surface-enhanced raman spectroscopy,SERS)原位研究金、银等无机纳米材料表/界面吸附的核酸、蛋白质、磷脂等生物分子,以及细胞、病毒和细菌等与金、银纳米材料表/界面作用的研究进展;综述了SERS技术在探索纳米-生物界面作用机制、生物分子测定、生物分子界面行为监测中的应用.     

SERS标记纳米粒子用于免疫识别

激光拉曼光谱技术近年来已成为研究生物分子结构常用的光谱手段.尤其在研究水溶液中蛋白质的结构和构象方面发挥了重要作用.然而,常规拉曼光谱的信号强度很低,限制了其在各个领域中的应用.表面增强拉曼光谱(SERS)和表面增强共振拉曼光谱(SERRS)技术可使信号增强6～10个数量级,尤其是SERS技术已发展到检测单分子的水平,更为其在生物方面的应用开拓了新的局.     

SERS生物传感技术及其应用进展

表面增强拉曼散射(SERS)生物传感技术是以生物成分为敏感元件或探测对象,研究生物分子间相互作用的重要工具之一,被广泛应用于环境监测、食品安全、临床检验及疾病诊断等众多领域.本文总结了耦合增强SERS生物传感技术方面的进展及其在分析检测和癌症诊断方面的应用.主要包括基于耦合增强SERS生物传感技术方法、高灵敏度的SERS传感芯片的制备及其应用和新型SERS技术研究癌细胞及组织.     

5,5'-二硫代双(琥珀酰亚氨基-2-硝基苯甲酸)功能化的SERS纳米探针在免疫检验中的应用

以5,5'-二硫代双(琥珀酰亚氨基-2-硝基苯甲酸)(DSNB)分子作为偶联剂将蛋白质结合在金纳米粒子表面,既保持了蛋白质的生物活性,同时DSNB分子又具有较高的表面增强拉曼散射(SERS)活性,可作为蛋白质定量分析的探针分子.选用生物素与亲和素的特异性识别以及抗原抗体的免疫识别2个生物反应体系,将SERS纳米探针固定在蛋白质检测芯片上.以硅片为蛋白质检测载体,利用硅片在520 cm-1处的拉曼特征峰为内标,对人Ig G抗体进行定量分析.结果表明,该探针对人Ig G抗体检测的最低浓度可以达到5 pg/m L.     

界面电场对血红蛋白在多孔金电极上的吸附和生物活性的影响(英文)

蛋白质的界面吸附及其生物活性因它在构建生物传感、生物电子器件和生物燃料电池等方面具有重要的作用而倍受关注.对此,界面电场是吸附的一个重要影响因素,它能明显地影响蛋白质分子在材料界面的吸附量、分子构象以及分子定向.本文应用电化学方法和红外光谱技术研究了血红蛋白在三维多孔金膜电极上的吸附动力学及其生物活性随界面电场的变化关系.结果表明,由界面电场产生的过量表面电荷可借助与蛋白质分子之间的静电作用加速蛋白质分子在电极表面的吸附,提高其吸附量;但是,过高的界面电场将破坏吸附蛋白质的构象以及降低它还原过氧化氢的催化活性;只有在零电荷电位下,吸附在电极表面的血红蛋白才能保持其天然的构象和生物催化活性.本研究将为生物传感器、生物电子器件和生物燃料电池的构建提供理论依据,加深对荷电生物界面上生物分子界面行为的认识.     

组蛋白乙酰化的耦合增强拉曼散射生物传感方法

提出了一种组蛋白乙酰化修饰检测的耦合增强拉曼散射生物传感新方法. 该方法以金纳米粒子为表面增强拉曼散射(SERS)基底, 表面修饰乙酰化组蛋白H3多肽为识别探针, 对甲氧基苯硫酚(4-MTP)为拉曼标记物, 制备了组蛋白乙酰化修饰检测的SERS纳米探针. 通过紫外可见吸收光谱与动态光散射分析, 证实了组蛋白乙酰化抗体可介导SERS纳米粒子发生可控组装与聚集, 使SERS纳米探针间发生局域电场共振耦合, 产生显著增强的SERS信号. 基于此, 通过待测抗原与SERS纳米探针对抗体的竞争性相互作用, 我们设计了组蛋白乙酰化修饰检测的竞争免疫SERS生物传感方法. 该法操作简便、快速、重现性好, 且裸眼即能进行可视化鉴定. 通过设计不同染料标记的SERS纳米探针, 该法有望实现多种组蛋白修饰的复合检测.     

负电性纳米银的制备及性质研究

制备了一种表面带负电的胶态纳米银,用透射电镜、吸收光谱、 SERS谱对该纳米银进行了研究.发现纳米银的粒径分布均匀,平均粒径为11 nm,吸收峰为422 nm,常温下放置7个月仍具有较强的SERS活性.当阴离子型分子吲哚丁酸、阳离子型分子碱性品红、亚甲兰及中性分子邻菲罗邻分别吸附在其上时,观察到阳离子型分子碱性品红和亚甲兰及中性分子邻菲罗邻的SERS谱,而阴离子型分子吲哚丁酸则无SERS谱出现.     

应用于基因分析的最新SERS技术*

表面增强拉曼散射（SERS）是一种基于拉曼散射原理识别生物及化学分子的分析方法。SERS具有灵敏度高、水干扰小、分辨率高、稳定性好等优点,广泛应用于生物分析和生物医学研究领域。近年来,SERS技术在基因分析领域得到迅速的发展,成为国内外研究的热点。本文对应用于基因分析的一些最新SERS技术（包括基因的免标记检测和标记检测）进行较为全面的综述,着重介绍了免标记检测中基于金属纳米粒子和针尖增强拉曼散射的SERS技术,标记检测中基于拉曼活性物、PCR技术、分子信标、基底和标记物的SERS信号放大技术,并概括了基因多组分检测技术及SERS技术的应用前景。     

Observation of dynamic oxygen release in hemoglobin using surface enhanced Raman scattering

Photoinduced oxygen dynamics in hemoglobin is monitored by surface enhanced resonant Raman spectroscopy (SERRS) using silver colloids. The spectra are characterized by massive transient amplifications which we assign to a charge-transfer mechanism during the opening of the heme-pockets in the release of oxygen. This transient lifts the selection rule specificity of normal Raman active modes and allows for the full density of states of the hemes to be observed. The amplification of specific forbidden modes is controlled by the orientation alignment of individual molecules in proximity with the colloid surface. We propose that the technique can be used to monitor oxygen release in single proteins.     

Hemoprotein bioconjugates of gold and silver nanoparticles and gold nanorods: structure-function correlations

Bioconjugates of the hemoproteins, myoglobin, and hemoglobin have been synthesized by their adsorption on spherical gold and silver nanoparticles and gold nanorods. The adsorption of hemoproteins on the nanoparticle surface was confirmed by their molecular ion signatures in matrix assisted laser desorption ionization mass spectrometry and specific Raman features of the prosthetic heme b units. High-resolution transmission electron microscopy (HRTEM) and UV-visible spectroscopy showed that the particles retain their morphology and show aggregation only in the case of silver. The binding of azide ion to the Fe(III) center of the prosthetic heme b moiety caused a red shift of the Soret band, both in the case of the bioconjugates and in free hemoproteins. This was further confirmed by the characteristic signature at 2050 cm-1 in the Fourier-transform infrared spectra, which corresponds to the asymmetric stretching of the Fe(III) bound azide. The retention of the chemical behavior of the prosthetic heme group after adsorption on the nanoparticle is interesting due to its implications in nanoparticle supported enzyme catalysis. The absence of morphology changes after the reaction of bioconjugates with azide ion observed in HRTEM studies implies the stability of nanoparticles under the reaction conditions. All these studies indicate the retention of protein structure after adsorption on the nanoparticle surface.     

含氨基酸席夫碱的5-氟尿嘧啶类衍生物在银溶胶上的吸附状态研究

合成了三种含氨基酸席夫碱的5-氟尿嘧啶类衍生物,用元素分析和1H NMR表征了它们的结构;用拉曼光谱（RS）和表面增强拉曼光谱（SERS）研究目标化合物在银溶胶上的吸附状态,推测其SERS增强机理.结果表明：在银溶胶表面上,羧基氧原子与银形成化学建,苯环是稍微倾斜地吸附在银胶面上,其它部分则平躺吸附于银溶胶表面.     

Preparation of Nanoelectrode Ensembles by Assembly of Nano—Silver Colloid on Gold Surface

A novel method for preparing silver nanoelectrode ensembles(SNEEs) and gold nanoelectrode ensembles (GNEEs) has been developed. Silver colloid particles were first absorbed to the gold electrode surface to form a monolayer silver colloid. N-hexadecyl nercaptan was then assembled on the electrode to form a thoil monolayer on which hydrophilic ions cannot be transfered. The SNEEs was prepared by removing thiol from silver colloid surface through applying and AC voltage with increasing frequency at 0.20V(vs.SCE). Finally,GNEEs was obtained by immersing a SNEEs into 6 mol/L HNO3 to remove the silver colloid particles. By comparison with other methods such as template method ect., this method enjoys some advantages of lower resistance, same diameter,easy preparation,controllable size and density.     

吸附于银胶颗粒表面的胆红素及胆绿素分子吸附取向研究

胆红素、胆绿素作为重要的生物小分子被广泛研究。本文采用表面增强拉曼光谱技术获得了胆红素和胆绿素分子吸附于银胶颗粒表面的拉曼光谱。通过对其谱带的指认分析,表明胆红素形成了三对内氢键,并以其两个吡咯亚甲基酮环沿银胶颗粒表面切向方向镶嵌在银胶颗粒上,而胆绿素则以顺式－顺式－顺式构型平躺吸附于银胶颗粒表面。     

肌红蛋白-纳米氧化铝模板-金胶复合组装体的直接电化学与电催化

将肌红蛋白(Mb)固定在纳米氧化铝(AAO)模板-金胶复合组装体修饰玻碳电极表面,制得Mb/AAO/Au colloid/GC薄膜电极.在pH=5.4的HAc-NaAc缓冲溶液中,该薄膜电极于-0.21 V(vs.Ag/AgC l)处有一对准可逆的氧化还原峰,为Mb血红素辅基Fe(Ⅲ)/Fe(Ⅱ)电对的特征峰.在AAO/Au colloid薄膜的微环境中,Mb与玻碳电极间的电子传递明显加快,该Mb/AAO/Au colloid/GC薄膜电极还可用于过氧化氢和溶解氧的催化还原.     

3种D-氨基葡萄糖席夫碱化合物在银溶胶上的吸附状态

合成了3种D－氨基葡萄糖席夫碱化合物,研究了它们的表面增强拉曼光谱、傅里叶变换拉曼光谱,探讨了它们在银溶胶上的吸附状态和表面增强机理,发现这类化合物以化学吸附模式为主,结构相似的化合物在银溶胶上的吸附状态不一定完全相同。     

Electron transfer of hemoglobin at electrodes modified with colloidal clay nanoparticles

Nanostructured sodium montmorillonite was prepared via a colloidal chemical approach and deposited onto glassy carbon electrodes (GCE). Subsequently, hemoglobin was spontaneously adsorbed onto the clay membrane-modified electrode. The colloidal clay nanoparticles and the adsorbed protein were characterized by scanning electron microscopy (SEM) and atomic force microscopy (AFM). The electrochemical impedance behavior of the system was studied using a microlithographically fabricated interdigitated microsensor electrode (IME). The interaction of the clay nanoparticles with hemoglobin was investigated by UV-VIS spectroscopy and electrochemical methods. The heme protein adsorbed in this way displayed a well-defined electrode process and the electron transfer was confirmed to originate from its heme site. Furthermore, nitric oxide affects the hemoglobin electrochemistry.     

新型银胶基底研究HSA的近红外表面增强拉曼散射

用紫外—可见两步光化学还原法，合成了等离子体共振峰出现在近红外区的新 型绿色银胶．首次用该银胶作为基底研究人血清白蛋白(HSA)的近红外表面增强拉 曼散射(NIR—SERS)，发现银胶中的线状银纳米粒子聚集体有较强的NIR—SERS效应 和生物兼容性，这为研究生物大分子的结构、构象和界面作用提供了一种较为理想 的活性基底．由所得到的NIR—SERS光谱可发现，吸附在银纳米粒子表面的HSA的肽 链骨架仍以α—螺旋结构为主，其二级构象特征基本不变；吸附作用诱导部分芳香 氨基酸残基所处的微环境发生改变，趋于银纳米粒子表面．此外，明显观察到 COO^-与C—S的特征谱带说明HSA中去质子的羧基氧、二硫桥键的硫直接与银纳米粒 子表面作用．     

Highly sensitive voltammetric biosensor for nitric oxide based on its high affinity with hemoglobin

Although heme protein-based, amperometric nitric oxide (NO) biosensors have been well documented in previous studies, most have been conducted in anaerobic conditions. Herein we report a novel hemoglobin-based NO biosensor that is not only very sensitive but also usable in air. The heme protein was entrapped in a sodium montmorillonite film, which was immobilized at a pyrolytic graphite electrode surface. Film-entrapped hemoglobin can directly exchange electrons with the electrode, and this process has proven to favor the catalytic reduction of oxygen. In addition, NO induced a cathodic potential shift of the catalytic reduction peak of oxygen. This potential shift was proportional to the logarithm of NO concentration ranging from 4.0 × 10⁻¹¹ to 5.0 × 10⁻⁶ mol/L. The detection limit has been estimated to be 20 pM, approximately four orders lower than previously reported amperometric detectors.