超导与生物电子学中德联合实验室揭牌

不久前,中国科学院上海微系统与信息技术研究所、德国尤利希研究中心（Forschungszentrum Julich）生物与纳米系统研究所（Institute of Bio—and Nanosystems,IBN一2）超导与生物电子学联合实验室揭牌仪式在上海微系统所举行。上海微系统所所长王曦院士、尤利希研究中心生物纳米系统研究所所长AndreasOffenhaeusser教授为联合实验室揭牌。来自美国、德国、日本、印度等国家的超导应用专家及我国知名学者吴培亨院士等专家,以及上海微系统所相关人员参加了揭牌仪式。     

生物高分子材料在药物传递系统中的降解 Ⅱ.降解动力学及应用

生物高分子材料在现代药物传递系统中不仅起着载体的作用,而且同时影响和控制药物的缓释机理。文章是《生物高分子材料在药物传递系统中的降解Ⅰ.机理与表征方法》的续篇,主要阐述了生物高分子材料在药物传递系统中的降解动力学。     

基于石墨烯及其衍生物的生物传感系统

由于石墨烯或其衍生物具有的独特的电、热、机械、光及电化学性能,特别是单层石墨烯或其衍生物极高的载流子迁移率、良好的导电性、高比表面积、易于功能化、强荧光猝灭性和生物分子亲和力,尤适于生物传感系统的构建。本文对近几年来石墨烯及其衍生物在场效应晶体管、电化学、压电晶体、光致发光及电化学发光生物传感系统方面的研究情况进行了综述。     

森林生态系统汞的生物地球化学过程

森林系统占全球陆地总面积的31%,是全球生物地球化学循环最活跃的地区之一。认识森林系统汞的生物地球化学过程对确立大气-森林系统汞的相关归趋,及进一步定量分析全球汞的生物地球化学循环过程至关重要。然而,当前森林系统在全球大气汞的循环中的角色认识还不清楚,即无法确定森林系统是大气汞的汇还是源。本文基于森林系统汞的质量平衡、土壤汞的累积过程及汞的同位素地球化学的研究,阐述了当前关于汞在全球森林生态系统多介质间汞的相互耦合作用过程及其迁移转化规律的认识。在此基础上,针对当前森林系统汞的生物地球化学过程研究的关键科学问题,提出了未来该领域的研究重点和方向。     

•前言•生物医用高分子

“生物医用高分子”是生物材料的最重要组成部分, 是保障人类健康的必需品; 其应用不仅挽救了数以千万计人的生命, 提高了生命质量, 且对医疗技术和保健系统的革新、降低医疗费用也具有引导作用. 同时, 生物医用高分子又是高分子材料科学的重要分支, 是21世纪高分子材料科学, 特别是功能高分子或精细高分子领域内非常活跃而又重要的前沿发展方向. 作为一类生物材料, 在使用过程中必然与生理系统(血液、组织、细胞等)或其组成部分(蛋白、酶、DNA、多糖、无机盐和各类生物小分子)相接触, 因此其研究与发展与生命科学和医学也密切相关. 生物医用高分子的特征之一是生物功能性(biofunctionality), 即能够对生物体进行疾病诊断、组织替换或修复; 之二是生物相容性(biocompatibility), 即材料引起适当的机体反应的能力, 是区别于其他高技术材料的最重要的特征, 包括不引起生物体组织、血液等不良反应. 现代医学的进步与生物材料的发展密不可分, 如各种介入诊断和治疗导管、药物传递控释系统、创伤和烧伤敷料、血管内支架、人工关节与功能性假体等已得到广泛的应用. 但是, 生物医用高分子材料涉及化学、材料、生物、医学以及物理等诸多学科领域, 其使用又与生理系统相接触, 因此该材料的研究与开发具有相当的难度和挑战.     

基于海水淡化的生物电化学脱盐技术研究进展及应用前景

生物电化学脱盐技术是一种在生物电化学基础上发展起来的微生物脱盐池与传统海水淡化技术的耦合,为海水淡化提供了一种全新的低能耗的方法。本文综述了自2009年微生物脱盐池问世以来的研究进展。简要介绍了生物电化学脱盐的基本原理和系统评价参数;比较了生物电化学脱盐系统构型对脱盐效率的影响;探讨了生物电化学脱盐过程中的限制因素;展望了生物电化学脱盐技术在海水淡化方面的应用前景。     

共振散射相关光谱一种新的单颗粒探测方法

基于共焦构型构建了共振散射相关光谱新方法, 阐明了共振散射相关光谱的原理, 并利用纳米金的共振散射特性, 将纳米金标记到生物分子上. 考察了该系统的重现性以及溶液粘度、粒径、浓度和激光能量对金纳米粒子在溶液中扩散行为的影响. 结果表明, 共振散射相关光谱可以替代荧光相关光谱, 应用于生物分析和某些生物系统研究.     

化学基元组学与药物创新

化学基元组学（chemomics）是与化学信息学、生物信息学、合成化学等学科相关的交叉学科．生物系统从内源性小分子（天然砌块）出发,通过酶催化的化学反应序列制造天然产物．生物系统通过化学反应和天然砌块向目标天然产物“砌入”一组原子,这样的一组原子称为化学基元（chemoyl）．化学基元组（chemome）是生物组织中所含有的化学基元的全体．化学基元组学研究各种化学基元的结构、组装与演化的基本规律．在生存压力和繁衍需求的驱动下,生物系统已经进化出有效手段来合成天然产物以应付环境的变化,并产生了丰富多彩的生物和化学多样性．近年来,人们意识到药物创新的瓶颈之一是药物筛选资源的日益枯竭．化学基元组学可以解决这个瓶颈问题,它通过揭示生物系统制备化学多样性的规律,发展仿生合成方法制备类天然化合物库（quasi natural product libraries）以供药物筛选．本文综述了化学基元组学的主要研究内容及其在药物创新各领域中的潜在应用．     

化学基元组学与药物创新

化学基元组学(chemomics)是与化学信息学、生物信息学、合成化学等学科相关的交叉学科.生物系统从内源性小分子(天然砌块)出发,通过酶催化的化学反应序列制造天然产物.生物系统通过化学反应和天然砌块向目标天然产物"砌入"一组原子,这样的一组原子称为化学基元(chemoyl).化学基元组(chemome)是生物组织中所含有的化学基元的全体.化学基元组学研究各种化学基元的结构、组装与演化的基本规律.在生存压力和繁衍需求的驱动下,生物系统已经进化出有效手段来合成天然产物以应付环境的变化,并产生了丰富多彩的生物和化学多样性.近年来,人们意识到药物创新的瓶颈之一是药物筛选资源的日益枯竭.化学基元组学可以解决这个瓶颈问题,它通过揭示生物系统制备化学多样性的规律,发展仿生合成方法制备类天然化合物库(quasi natural product libraries)以供药物筛选.本文综述了化学基元组学的主要研究内容及其在药物创新各领域中的潜在应用.     

生物高分子材料在药物传递系统中的降解 Ⅰ.机理与表征方法

生物高分子材料在现代药物传递系统中不仅起着载体的作用,而且还影响和控制药物的缓释机理。文章为第一部分,主要介绍生物高分子材料在药物传递系统中的降解机理与表征方法。     

Increasing the sensitivity of Listeria monocytogenes assays: evaluation using ELISA and amperometric detection

An immunosensor for the detection of Listeria monocytogenes was developed. ELISA and amperometric studies were run in parallel to develop a more sensitive and rapid assay for the bacterium. Conditions for the immunosensor were primarily characterised using ELISA. A direct sandwich assay was employed and the affinities of two polyclonal (goat and rabbit) and one monoclonal (mouse) anti-L. monocytogenes antibodies were compared using this format. Owing to low sensitivity being obtained with all antibodies, biotin-avidin amplification and an indirect sandwich assay were employed. The system was then transferred to screen-printed electrodes (SPEs), the primary antibody being immobilised by cross-linking with 1-ethyl-3-(3-dimethylaminopropyl)-carbodiimide, and the mode of detection being amperometric. Various parameters (limit of detection, working range, incubation time, cross-reactivity) of the systems were characterised. The effect of direct incubation in milk is also discussed. The final immunosensor had a working range of 1 x 10(6)-1 x 10(3) cells ml-1 and a detection limit of 9 x 10(2) cells ml-1. The assay took about 3.5 h to complete.     

双重信号放大的竞争型免疫传感器的制备及其应用于瘦肉精检测的研究

制备了葡萄糖氧化酶(GOD)-克伦特罗(Clenbuterol, CB)功能纳米复合物, 并采用共价键合和温育组装等方法构建了双重信号放大的竞争型免疫传感器. 研究了GOD 催化氧化葡萄糖和普鲁士蓝(PB)催化还原H2O2 双重信号放大的反应机理和传感器检测CB 的作用机制. 用扫描电子显微镜(SEM)等方法表征了纳米复合材料的形貌和复合物中GOD的活性, 复合物中的GOD 保持了良好的电催化性能和酶动力学响应, 并且符合米氏动力学方程. 最佳实验条件下, 该免疫传感器对盐酸克伦特罗的检测线性范围为0.01～100 ng/mL, 检测限达4.50 pg/mL. 实验结果表明, 该传感器对瘦肉精克伦特罗的检测具有灵敏度高, 特异性强, 重现性好, 线性范围宽和检测限低等优点. 将该方法用于猪肝样品的分析, 加标样品回收率在97.5%～102%之间. 该研究为瘦肉精及β-受体兴奋剂的分析提供了一种新方法.     

Detection of complement C4 with a piezoelectric immunosensor

A piezoelectric immunosensor has been developed for the detection of complement C4. Anti-C4 antibody was immobilized onto the gold electrodes of a 9 MHz AT-cut piezoelectric crystal. The coated crystal with the physical adsorption method to immobilize antibody showed the better results than the polyethyleneimine adhesion, glutaraldehyde cross-linking method with respect to sensitivity and reproducibility. The antibody-bound crystal with the physical adsorption method was successfully used for the detection of human complement C4 in the concentration range of 0.1-10 μg/mL for 40 min incubation time. The immunosensor system had good selectivity, and other materials in human serum did not interfere the detection remarkably. The crystal could be regenerated nearly 15 times when the bound materials on the crystal surface were eluted by strong acid and strong alkali solutions and subsequently cleaned in a ultrasonic cleaner.     

Magnetic beads-based electrochemiluminescence immunosensor for determination of cancer markers using quantum dot functionalized PtRu alloys as labels

A novel electrochemiluminescence (ECL) immunosensor for sensitive detection of human chorionic gonadotrophin antigen (HCG-Ag) was constructed using CdTe quantum dot functionalized nanoporous PtRu alloys (QDs@PtRu) as labels for signal amplification. In this paper, nanoporous PtRu alloy was employed as the carrier for immobilization of CdTe QDs and antibodies. Primary monoclonal antibody to alfa-HCG antigen (McAb(1)) was immobilized onto the surface of chitosan coated Fe(3)O(4) magnetic nanoparticles (Fe(3)O(4)/CS MNPs) by glutaraldehyde (GA) as coupling agent. Then McAb(1) could be easily separated and assembled on the surface of indium tin oxide glass (ITO) owing to their excellent magnetic properties with external magnetic forces holding the MNPs. Due to signal amplification from the high loading of CdTe QDs, 4.67-fold enhancements in ECL signal for HCG-Ag detection was achieved compared to the unamplified method (single QDs as labels). Under optimal conditions, a wide detection range (0.005~50 ng mL(-1)) and low detection limit (0.8 pg mL(-1)) were achieved through the sandwich-type immunosensor. The novel immunosensor showed high sensitivity and selectivity, excellent stability, and good reproducibility, and thus has great potential for clinical detection of HCG-Ag. In particular, this approach presents a novel class of combining bifunctional nanomaterials with preferable ECL properties and excellent magnetism, which suggests considerable potential in a wide range of applications for bioassays.     

Prussian blue–gold nanoparticles-ionic liquid functionalized reduced graphene oxide nanocomposite as label for ultrasensitive electrochemical immunoassay of alpha-fetoprotein

In this work, poly(diallyldimethylammonium chloride) (PDDA) protected Prussian blue/gold nanoparticles/ionic liquid functionalized reduced graphene oxide (IL-rGO-Au-PDDA-PB) nanocomposite was fabricated. The resulting nanocomposite exhibited high biocompatibility, conductivity and catalytic activity. To assess the performance of the nanocomposite, a sensitive sandwich-type immunosensor was constructed for detecting alpha-fetoprotein (AFP). Greatly enhanced sensitivity for this immunosensor was based on triple signal amplification strategies. Firstly, IL-rGO modified electrode was used as biosensor platform to capture a large amount of antibody due to its increased surface area, thus amplifying the detection response. Secondly, a large number of Au-PDDA-PB was conjugated on the surface of IL-rGO, which meant the enrichment of the signal and the more immobilization of label antibody. Finally, the catalytic reaction between H₂O₂ and the IL-rGO-Au-PDDA-PB nanocomposite further enhanced the signal response. The signals increased linearly with AFP concentrations in the range of 0.01–100 ng mL⁻¹. The detection limit for AFP was 4.6 pg mL⁻¹. The immunosensor showed high sensitivity, excellent selectivity and good stability. Moreover, the immunosensor was applied to the analysis of AFP in serum sample with satisfactory result.     

石墨烯-壳聚糖-纳米金修饰的免疫传感器应用于1-芘丁酸的检测研究

本文采用石墨烯(GS)-壳聚糖(CS)-纳米金(Nano-Au)复合材料修饰玻碳电极,构建性能良好的生物识别界面,制备一种无标记的电流型免疫传感器,并应用于1-芘丁酸(PBA)的高灵敏检测。研究结果表明,GS、CS和Nano-Au的协同作用,极大地提高了anti-PAHs抗体在电极表面的覆盖量,从而提高了免疫传感器的灵敏度和检测性能。采用示差脉冲伏安法(DPV)对PBA进行检测,PBA在0.001~10ng/mL和10~200ng/mL浓度范围内与峰电流值呈良好的线性关系,检出限为0.001ng/mL。该传感器应用于实际水样中痕量PBA的检测,加标回收率为90%~105%。     

Gold nanoparticle-labeled detection antibodies for use in an enhanced electrochemical immunoassay of hepatitis B surface antigen in human serum

The application of gold nanoparticle-based electrochemical immunoassays have been extensively studied for the detection of hepatitis B surface antigen (HBsAg), but most often they exhibit low sensitivity. We describe the fabrication of a new electrochemical immunoassay for signal amplification of the antigen-antibody reaction combined with the nanogold-based bio-barcode technique. Hepatitis B surface antibody (HBsAb) was initially immobilized on a nanogold/thionine/DNA-modified gold electrode, and then a sandwich-type immunoassay format was employed for the detection of HBsAg using nanogold-codified horseradish peroxidase-HBsAb conjugates as secondary antibodies. Under optimal conditions, the current response of the sandwich-type immunocomplex relative to the H₂O₂ system was proportional to HBsAg concentration in the range from 0.5 to 650 ng·mL^?1 with a detection limit of 0.1 ng·mL^?1 (S/N?=?3). The precision, reproducibility and stability of the immunosensor were acceptable. Subsequently, the immunosensors were used to assay HBsAg in human serum specimens. Analytical results were in agreement with those obtained by the standard chemiluminescence enzyme-linked immunosorbent assay.     

Sensitive detection of thyroid stimulating hormone by inkjet printed microchip with a double signal amplification strategy

In this paper, we reported a sensitive electrochemical immunosensor coupling protein A/G@magnetic beads and an ALP-based enzymatic-electrochemical reaction on the inkjet printing microchips for the determination of thyroid stimulating hormone.     

Double‐Layer Nanogold and Double‐Strand DNA‐Modified Electrode for Electrochemical Immunoassay of Cancer Antigen 15‐3

Various sensor‐based immunoassay methods have been extensively developed for the detection of cancer antigen 15‐3 (CA 15‐3), but most often exhibit low detection signals and low detection sensitivity, and are unsuitable for routine use. The aim of this work is to develop a simple and sensitive electrochemical immunoassay for CA 15‐3 in human serum by using nanogold and DNA‐modified immunosensors. Prussian blue (PB), as a good mediator, was initially electrodeposited on a gold electrode surface, then double‐layer nanogold particles and double‐strand DNA (dsDNA) with the sandwich‐type architecture were constructed on the PB‐modified surface in turn, and then anti‐CA 15‐3 antibodies were adsorbed onto the surface of nanogold particles. The double‐layer nanogold particles provided a good microenvironment for the immobilization of biomolecules. The presence of dsDNA enhanced the surface coverage of protein, and improved the sensitivity of the immunosensor. The performance and factors influencing the performance of the immunosensor were evaluated. Under optimal conditions, the proposed immunosensor exhibited a wide linear range from 1.0 to 240 ng/mL with a relatively low detection limit of 0.6 ng/mL (S/N=3) towards CA 15‐3. The stability, reproducibility and precision of the as‐prepared immunosensor were acceptable. 57 serum specimens were assayed by the developed immunosensor and standard enzyme‐linked immunosorbent assay (ELISA), respectively, and the results obtained were almost consistent. More importantly, the proposed methodology could be further developed for the immobilization of other proteins and biocompounds.     

Biomolecule‐Doped Organic/Inorganic Hybrid Nanocomposite Film for Label‐Free Electrochemical Immunoassay of α‐1‐Fetoprotein

A new electrochemical immunosensor for the detection of α‐1‐fetoprotien (AFP) was developed based on AFP antibody (anti‐AFP)‐functionalized organic/inorganic hybrid nanocomposite membrane. To fabricate such a hybrid composite membrane, 3,4,9,10‐perylenetetracarboxylic acid‐bound thionine molecules (PTCTH) were initially doped into titania colloids (TiO₂), and then gold nanoparticles and anti‐AFP were immobilized onto the composite film in turn. Comparison with the electrode fabricated only with thionine not 3,4,9,10‐perylenetetracarboxylic acid, the immunosensor with PTCTH exhibited high sensitivity and fast electron transfer. The presence of gold nanoparticles provided a good microenvironment for the immobilization of biomolecules, enhanced the surface coverage of protein, and improved the sensitivity of the immunosensor. The modified process was characterized by scanning electron microscope (SEM), cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). The surface topography of the membrane was investigated by scanning electron microscopy (SEM). Under optimal conditions, the proposed immunosensor exhibited a wide linear range from 2.5 to 200.0 ng/mL towards AFP with a detection limit of 0.5 ng/mL (S/N=3). The stability, reproducibility and precision of the immunosensor were acceptable. Comparison with the conventional enzyme‐linked immunosorbent assay (ELISA), the present method did not require more labeled procedures and washing steps. Significantly, the detection methodology provides a promising approach for other proteins or biosecurities.