光学蛋白质芯片法测定甲胎蛋白的初步研究

采用微流道反应器系统,优化甲胎蛋白单克隆抗体浓度,并装配在醛基改性后的硅片表面上,经牛血清白蛋白封闭后形成检测AFP芯片阵列。通过制作AFP浓度梯度标准曲线标定光学蛋白质芯片,实现肿瘤标志物AFP的检测,结果表明,该方法的最低测定浓度可以达到1.0ng/mL,变异系数为3.1%,回收率在94.4 105.0%之间,与人纤维蛋白原的交叉反应率≤0.25%、与1%葡萄糖≤0.08%、与人源IgG≤0.16%和与人血清白蛋白≤0.20%,说明光学蛋白质芯片技术检测AFP,灵敏度高、重复性好、操作简便,有望应用于临床检测

A One-Step Immunoassay for Carbohydrate Antigen 19-9 by Biosensor Based on Imaging Ellipsometry

 Cancer markers can offer much more information for developing or developed cancers. Simple and short-time assay of cancer biomarker is essential for clinic diagnosis and management. In this study, a one-step immunoassay for carbohydrate antigen 19-9 (CA19-9) by biosensor based on imaging ellipsometry (BIE) is described and its analysis performances are evaluated. Anti-CA19-9 monoclonal antibody as ligand covalently immobilized on carboxyl-modified silicon substrate and its immobilization concentration concurrently screened. Then, bovine serum albumin (BSA) is used to block for acquisition of sensing layer. The detection linear range is from 15.0 to 120.0 U/mL with a minimum limit of 10.0 U/mL (S/N = 3). The intra-slide and inter-slide reproducibility, expressed as coefficient variation (CV%), are 9.9, 5.9, 5.4% and 9.6, 7.6, 5.3% for 31.9, 57.4, and 99.2 U/mL of CA19-9, respectively. Accuracy determined by spiked-recovery is among 95.1-106.7%. Specificity expressed as cross-reaction rate are all below 5.8% evaluated by three analogous biomarkers alpha-fetoprotein (AFP), carcinoembryonic antigen (CEA), and carbohydrate antigen 242 (CA242). Application of BIE to 25 clinic samples demonstrated that the results are in high correlate with electrochemiluminescent immunoassay (ECLIA, R-2 = 0.997). The proposed immunoassay has the potential for clinic application

Preparation of single molecular film of protein A to assemble antibody for construction of biomarker chip

免疫分析方法主要依赖于固定在固相基底上的抗体对相应抗原的特异性识别,抗体在固相基底上固定后最大程度保持生物学活性是设计免疫分析方法的关键技术.本研究利用在疏水性硅基底表面制备蛋白A单分子膜层可以特异结合抗体的Fc端,进而实现对抗体的定向化装配,进一步构建格式化阵列用于肿瘤标志物检测.研究结果表明,制备的蛋白A单分子膜层的厚度为1.8±0.6nm,抗体可以经蛋白A单分子膜层实现定向化装配,由此设计的传感阵列检测肿瘤标志物甲胎蛋白(alpha-fetoprotein,AFP)可以实现1.0ng/mL的灵敏度,血清检测结果与电化学法(ECLIA)测定进行统计学检验没有显著性差异(P>0.05)

Detection of duck hepatitis virus serotype1 by biosensor based on imaging ellipsometry

 A novel method for the detection of duck hepatitis virus serotype1 (DHV1) using a biosensor based on imaging ellipsometry (IE) is developed. Polyclonal antibodies against DHV1 were immobilized on silicon wafers through protein A and used to capture virus particles in sample. Signals on silicon surface were acquired directly in grayscale format on an imaging ellipsometry image. This study demonstrated that the assay is rapid and accurate for detection of duck hepatitis virus. Compared with traditional methods, this technique not only has high sensitivity as low as 8 x 10(-9.5) LD(50)/ml, but can also simultaneously perform multiple serotype identification of DHV1, DHV1-g and DHV1-s. These results suggest that this biosensor might be a practicable diagnostic tool for duck hepatitis virus detection

制备蛋白A单分子膜层装配抗体构建肿瘤标志物检测芯片

免疫分析方法主要依赖于固定在固相基底上的抗体对相应抗原的特异性识别,抗体在固相基底上固定后最大程度保持生物学活性是设计免疫分析方法的关键技术.本研究利用在疏水性硅基底表面制备蛋白A单分子膜层可以特异结合抗体的Fc端,进而实现对抗体的定向化装配,进一步构建格式化阵列用于肿瘤标志物检测.研究结果表明,制备的蛋白A单分子膜层的厚度为1.8±0.6nm,抗体可以经蛋白A单分子膜层实现定向化装配,由此设计的传感阵列检测肿瘤标志物甲胎蛋白(alpha-fetoprotein,AFP)可以实现1.0ng/mL的灵敏度,血清检测结果与电化学法(ECLIA)测定进行统计学检验没有显著性差异(P>0.05)

大速差同向射流——一种新型火焰稳定与强化燃烧的空气动力学原理

本文介绍了一种稳定火焰和强化燃烧的新型空气动力学原理——大速差同向射流技术。单股或多股高速小射流(空气、蒸汽或其它气体)与低速的主气流(燃料和空气混合物)同方向射入燃烧室,可以产生高湍流强度的大回流区,从而可以使可燃混合物与高温回流烟气有效地混合,以维持燃烧室内稳定而强化地燃烧,甚至对于着火性能很差的燃料也是如此。这是继传统的旋流燃烧器和钝体燃烧器之后又一种新型的有效而实用的火焰稳定方法。基于这种原理研制的煤粉燃烧器更具有优良的性能,并且在结构上也很简单。这种类型的煤粉预燃室,已经在电站和工业锅炉上安装使用。目前,使用这种预燃室可以在冷风条件下成功地启动贫煤(V~f30％)锅炉及低负荷情况下仍能维持燃烧。这项新技术所展示的火焰稳定和强化燃烧原理在燃烧界引起了广泛的关注和兴趣

Detection of alpha-fetoprotein through biological signal amplification by biosensor based on imaging ellipsometry

 High sensitive and quantitative detection of alpha-fetoprotein (AFP) by biosensor based on imaging ellipsometry (BIE) through biological amplification was investigated. AFP firstly reacted with the rat monoclonal antibody (rat-mAb) initially immobilized on glutaraldehyde modified silicon surface, then rabbit anti-human AFP polyclonal antibodies (Rabbit-pAb) and goat anti-rabbit IgG (goat-IgG) were sequentially applied to amplify signal. Results revealed that signal was enhanced approximately six fold. The linear range of AFP detection was 20.0-200.0 ng/ml with a low limit of 5.0 ng/ml (S/N = 3). The cross-reaction rate was less than 5.2% evaluated by biomarker (carcinoembryonic antigen, carbohydrate 19-9 and carbohydrate antigen 242) and two common proteins (human serum albumin, fibrinogen) and their mixture. Coefficient variation (CV) for intra-slide and inter-slide reproducibility were 10.3%, 6.6%, 6.3% and 10.7%, 7.9%, 6.4% for 41.6 ng/ml, 83.2 ng/ml and 128.4 ng/ml AFP. In clinic application, cut-off value at 28.6 ng/ml was also determined with sensitivity 0.72 and specificity 0.94. Results of 47 clinic patient samples detected by BIE were in good agreement with those of electrochemiluminescence immunoassay (ECLIA) (R2 = 0.9949). The area under receiver operating characteristic curve (ROC) curve is 0.89. Statistical analysis showed that BIE is high agreement with ECLIA (Kappa = 0.733, U = 3.21>U0.01). It shows a potential for hepatocellular carcinoma (HCC) diagnosis

Biosensor based on imaging ellipsometry for serotype-specific detection of Riemerella anatipestifer

<font face="times new roman,times" size="3">In this study, a practicable method for the detection of Riemerella anatipestifer (R. anatipestifer) using biosensor based on imaging ellipsometry (BIE) is described. The method is performed by immobilizing anti-R. anatipestifer egg yolk immunoglubilin (IgY) onto modified chemistry surface to form sensing layer. Antigen captured by sensing layer can then be quantitatively measured through imaging ellipsometry in grayscale format. The results demonstrate that it can detect R. anatipestifer as low as 5.2 x 10(3) CFU/mL. Furthermore, the proposed method can realize specific discrimination for multiple serotypes of 1,2, 4, and 14 of R. anatipestifer. It has the advantages of rapid, simple, high sensitivity and low cost.</font

Coflow jets with large velocity difference - a new aerodynamic principle of flame stabilization and combustion intensification

A new aerodynamic principle of flame stabilization and combustion intensification, the coflow jets with large velocity difference, is described. One or more small high-velocity jets of air or steam, injected off the axis and in the same direction as the low-velocity main fuel-air flow into the combustor, create a large recirculation zone of high turbulence intensity in which the combustibles and high temperature gases are effectively mixed, so that stable and intensive combustion can be maintained even for fuels with poor ignition. A pulverized coal combustor based on the principle mentioned above is shown to be characteristic of excellent combustoom and a simple structure. A number of precombustors of this type are in operation at some power stations and industrial boilers of China. Using such precombustor, successtul startups and part-load operation of the boilers have become available under conditions of unpreheated air and low-grade coal with volatiles as low as 15% and ash content as high as 30%. This principle shows good promise as an attractive new technology of combustion