电化学传感器用于菌体数实时检测方法的研究

基于微生物在新陈代谢过程中的电化学机理特征,提出一种实时检测菌体数的电化学方法;设计了生物电化学传感器和实时检测的电子装置,实验验证了该检测方法的可行性;与传统检测方法相比,具有快速、简便、实时检测等优点,对同一种试样的细菌含量的测定仅需要10 m in,而传统方法(标准平板培育法)至少需要24 h。     

用于识别人类白血病白细胞的 生物传感器的研究

本文介绍了一种以平面热解石墨电极为工作电极,用于识别健康人白细胞及白血病病人白细胞的半微分伏安型生物传感器.工作时,使抽滤在微孔滤膜上的白细胞与平面热解石墨电极紧密接触,然后于磷酸缓冲生理盐水中进行半微分循环伏安扫描.以同一扫描速率下的氧化峰电位(E_P),不同扫描速率下氧化峰电位的差值(△E_P),滤膜上单位细胞数的氧化电流的半微分值(e_p/cells),以及还原扫描有无还原峰等作为该生物传感器系统识别正常与异常白细胞的重要指标.     

一种葡萄糖氧化酶安培传感器研究

利用铁氰化钾作为电化学反应的媒介体,将葡萄糖氧化酶固定在羧甲基纤维素处理的碳电极表面,制成了一种新型的葡萄糖安培传感器.该传感器在恒电位0.4 V和葡萄糖氧化酶的催化作用下,使被检测物--葡萄糖--氧化,铁氰化钾还原,在电极表面产生灵敏氧化-还原峰,利用安培法可对葡萄糖进行间接测定.葡萄糖的测定范围为2.7～27 mmol/L,线性范围较好,拟合系数为0.997 8,灵敏度较当前葡萄糖传感器有明显的提高,11 s内即可达到输出稳态电流.同时该传感器对葡萄糖的测定避免了常规电化学传感器测定中样品所含大量的易氧化物质--如抗坏血酸和尿酸--带来的干扰.     

一种安培型尿酸生物传感器的初步研究

利用铁氰化钾作为电化学反应的媒介体,将尿酸氧化酶固定在羧甲基纤维素处理的碳电极表面,制成了一种新型的尿酸安培传感器.该传感器在恒电位0.3 V和尿酸氧化酶的催化作用下,使被检测物--尿酸--氧化,铁氰化钾还原,在电极表面产生灵敏的氧化-还原峰,然后利用安培法即可对尿酸进行间接测定.10秒内即可达到输出稳态电流,尿酸的测定范围为1 mg/dL～20 mg/dL,线性范围较好,拟合系数为0.9723.同时该传感器对尿酸的测定避免了常规电化学传感器测定中样品所含大量的易氧化物质带来的干扰.     

碳纳米管在生物传感器中的应用

碳纳米管是一种新型的纳米材料,将其用于修饰电极,可以降低化学物质氧化还原反应的过电位,改善生物分子氧化还原可逆性,其大比表面积有利于酶的固定化,还能促进酶活性中心与电极表面的电子传递.碳纳米管的这些特性对于提高生物检测的灵敏度和稳定性具有重大意义,为生物传感器领域开辟了广阔的前景.     

用于测定营养物质的通用生物传感器

报导了一种用于测定培养基中的养分的通用生物传感器.这种生物传感器以溶氧电极为基本传感器,在敏感膜上覆合上一种生物膜,用以测定一种假单孢菌培养液的醋酸铵的含量.其线性范围为:0~40mg/L;90%的响应时间为:15~20min;测定一个样品所需时间为40~60min;其测量精度为:±6%;使用寿命可达一年以上.     

基于集成参比电极的多参数水质监测微传感器阵列研制

研究了一种基于MEMS工艺制备的集成微电极型传感器,并用电化学修饰方法将Ag/AgCl参比电极集成在传感器上,用于水体中温度、电导率和氧化还原电位的测定.Pt温度传感器的电阻与温度的线性关系良好,满足温度测量精度的需求;比较法确定电导率传感器的电极常数为2.723,可以对一般水体的电导率进行测定;氧化还原电位传感器的标...     

L-半胱氨尾式卟啉铜(Ⅱ)自组装修饰金电极制备及对地表水中苯酚的检测

将制备的L-半胱氨卟啉铜(Ⅱ)(CuL)配合物自组装在Au电极表面,获得电化学苯酚传感器(CuL/Au CME).在pH7.0的磷酸盐缓冲液中于-0.4～0.5V(vs.SCE)电位范围内有一对氧化还原峰,其峰电位分别为氧化峰电位Epa=90mV,还原峰电位Epc=-60mV.实验表明该电极上,苯酚可被CuL催化氧化,通过产物在电位0.1 V下的电化学响应对苯酚进行测定,测定过程不需要再向体系中添加媒介体.该电极对苯酚表现出快速的响应(响应时间＜10s).传感器对苯酚的测定具有较宽的线性范围(5×10-7～2.5×10-4 mol/l),检出限为2.0×10-7mol/l.测定了电极稳定性,将该电极用于地表水中苯酚含量检测,并与标准4-氨基安替比林分光光度法作了对照,结果满意.     

高灵敏度双介体基胆固醇葡萄糖 生物传感器的研制及其临床试验结果

研制了灵敏高度、准确性好、取样量小（一滴指血或静脉血,≥２５μＬ）、测量迅速（胆固醇,６０ｓ;葡萄糖,３０ｓ）的夹心式生物传感器。它是由双介体多酶生物催化－氧化还原体系构成的电流型生物传感系统。本传感器可测量到人体从正常到异常的所有血总胆固醇／葡萄糖的含量范围,其临床评价工作已由中国卫生部临床检验中心完成。检验结果表明：所研制的胆固醇／葡萄糖传感器及其配套的测试仪器可实现总胆醇／总血糖的简便而又直     

用于污染物毒性检测的细菌发光传感器的研制

报导了一种快速测定污染物急性毒性的生物传感器法．该传感器由明亮发光杆菌固定化膜、硅光片、激光光功率计等组成的细菌发光传感器。具有检测毒性速度快、灵敏度高、重现性好、能分析毒性作用的动力学过程等特点．     

光纤SPR传感器在抗感染中药作用机理的应用

提出一种基于光纤表面等离子体共振（SPR）传感器的检测法,检测抗感染中药与细胞因子和受体间的相互作用.采用真空热蒸镀法镀双层金属膜制作一种双金属光纤SPR生物传感器,应用直接法完成中药作用机理检测.该传感器具有快速、客观、准确、高效的中药作用机理检测功能,获得了相应数据.光纤SPR生物传感器的应用使得中药作用机理过程的检测具有实时高效的优点,有望在抗感染中药作用的靶点和分子机理研究中取得新的突破.     

血液中C反应蛋白的SPR传感检测方法研究

利用表面等离子体共振（SPR）生物传感技术,建立了一种可以快速准确分析血样中C反应蛋白的新方法。SPR传感器采用Kretschmann结构的角度连续扫描方式,使用2个步进电机分别驱动棱镜和光电检测器件转动进行单一样本的高精度分析。将C反应蛋白抗体修饰于敏感芯片表面,通过SPR传感器对血样中C反应蛋白浓度进行检测分析。利用SPR方法和传统免疫比浊法分别检测标准C反应蛋白样本和200份感染性疾病儿童患者（7～10岁,男112名,女88名）的血液样本,结果表明：SPR方法检测标准样本的线性变化区域更大。在患儿血样的检测中,尽管2种方法的结果基本相同,但是SPR检测速度更快,样本需求量更小、重复性更佳。这表明SPR生物传感分析方法在C反应蛋白检测中比传统方法更具优势,有望在临床检验分析中得以广泛应用。     

Detection of incipient object slippage by skin-like sensing andneural network processing

Detection of incipient slippage is of great importance in robotics for the control of grasping and manipulation tasks. Together with fine-form reconstruction and primitive recognition, it has to be the main feature of an artificial tactile system. The system presented here is based on a neural network used to detect incipient slippage and on a skin-like sensor sensible to normal and shear stresses. Normal and shear stresses components inside the sensor are the input data of the neural net. An important feature of the system is that the a priori knowledge of the friction coefficient between the sensor and the object being manipulated is not needed. To validate the method we worked on both simulated and experimental data. In the first case, the finite element method is used to solve the direct problem of elastic contact in its full nonlinearity by resorting to the lowest number of approximations regarding the real problem. Simulation has shown that the network learns and is robust to noise. Then an experimental test was carried out. Experimental results show that, in a simple case, the method is able to detect the insipiency of slippage between an object and the sensor.     

聚酰亚胺隔热悬挂结构设计与制作

加热器在原子钟、气体传感器、生物传感器等器件中有着广泛的应用,降低加热功耗对于这些器件的实用化具有重要意义。设计并制作了一种集成了加热器和温度传感器的聚酰亚胺隔热悬挂结构,用于承载待加热的芯片,并利用集成制作在聚酰亚胺膜上的2组Pt线圈分别对芯片进行加热和温度检测。实验证明:聚酰亚胺隔热悬挂结构由热传导引起的功耗仅为没悬挂结构时的0.95%,大大降低了由热传导引起的功耗,即便在没有真空封装的情况下,在芯片工作在100℃时,功耗也可降低到36.7%;同时该结构也具有良好的机械性能,承载体积为14 mm×7 mm×1 mm的硅基芯片时,安全系数可达到56.58,具有很好的应用前景。     

Signal enhancement of surface plasmon resonance-based immunoassays for the allergen detection

A surface plasmon resonance (SPR) biosensor was used to determine the recombinant group 1 house dust mite allergen (rDer f1) in both HBS-EP buffer and fetal bovine serum (FBS). The monoclonal antibody was immobilized onto the CM5 sensor chip surface using an amine coupling method. The procedures of antibody immobilization and the subsequent primary and enhanced immunoassay were monitored in real time. The sensitivity for rDer f1 detection was remarkably improved by using intact polyclonal antibody as signal amplifying agent. Using this signal enhanced SPR immunosensor, rDer f1 in HBS-EP buffer and FBS was detected at a concentration of 15.4 and 32.1 ng/ml, respectively. The result demonstrates that SPR biosensor is a simple and reliable method for allergen detection.     

胆碱酯酶传感器及检测电路的设计制作

将胆碱酯酶固化到Ｈ＋－ＩＳＦＥＴ的栅极上，制成检测有机磷农药的酶场效应管传感器，介绍了该传感器的工作原理，制作方法及测试电路设计，探讨了它的响应特性并与色谱法作了对照，表明这是一种农药检测的简便快速、高效价廉的新方法和新仪器。     

Preparation of an electrochemical PNA biosensor for detection of target DNA sequence and single nucleotide mutation on p53 tumor suppressor gene corresponding oligonucleotide

Development of an electrochemical biosensor based on peptide nucleic acid (PNA) probe for detection of target DNA sequence and single nucleotide mutation in p53 tumor suppressor gene corresponding oligonucleotide using methylene blue (MB) as an electrochemical indicator is described. The interaction between MB and short sequence of p53, one of the most important tumor suppressor genes due to its dysfunction in the majority of human cancers, was studied by differential pulse voltammety (DPV). Probe modified electrode was prepared by self-assembled monolayer (SAM) formation of thiolated PNA molecules on the surface of gold electrode (GE). The hybridization of PNA probe with target DNA was performed in solution to form PNA-DNA hybrid on the surface of the GE. A significant increase in the reduction signal of MB was observed upon hybridization of the probe with the complementary DNA. The selectivity of the biosensor was studied using noncomplementary oligonucleotides. Furthermore, our results confirmed the ability of the sensor to detect single base mismatch in the sample oligonucleotide. The influence of probe concentration on the effective discrimination against noncomplementary sequence and point mutation was also investigated. Diagnostic performance of the biosensor is described and the detection limit is found 6.82 × 10⁻¹⁰ M. The electrochemical impedance spectroscopy was also employed to further investigate the sensor function.     

Performance of glucose biosensor based on oxygen electrode in physiological fluids and at body temperature

A potentially implantable glucose biosensor for continuous monitoring of glucose levels in diabetic patients has been developed. The glucose biosensor is based on an amperometric oxygen electrode and glucose oxidase immobilized on carbon powder held in the form of a liquid suspension. The enzyme material can be replaced (the sensor recharged) without sensor disassembly. Diffusion membranes made of silastic coatings over a microporous polycarbonate membrane are used. Calibration curves of the sensors in phosphate buffer solution and in undiluted blood plasma at body temperature have been obtained. The reproducibility of the sensor response in serum at body temperature is demonstrated. The sensors have a stable signal during storage and continuous operation at body temperature for a period of at least one month.     

利用参比型SPR生物传感器进行SARS病毒抗原检测的研究

参比型SPR生物传感器是一种可以在单通道内实现对检测、参比两个位点同时检测的新型SPR分析系统.利用参比型SPR生物传感器在线制备了两种SARS病毒抗原的检测芯片.直接固定抗体法制备的检测芯片在检测时基本无反应;蛋白A固定抗体法制备的芯片在通入灭活SARS病毒时检测信号明显,参比信号略有上升.第二种芯片可以直接检测到病毒培养液上清中的灭活SARS病毒,检测灵敏度已达到1.66×104 PFU/mL.参比位点可以用来检测待测物中杂质引起的非特异性吸附.