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131.
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利用双纳米金探针结合基因芯片平台建立了一种检测乙肝病毒基因(HBV DNA)的新方法. 根据HBV DNA的保守序列设计捕获探针和信号报告探针, 通过一对互补的纳米金检测探针的双杂交法对HBV DNA进行信号放大, 最后进行银染, 达到对HBV DNA的可视化检测. 该方法的灵敏度高, 可检测10 fmol/L的HBV DNA, 且能在1.5 h内完成检测. 其具有的快速、 高灵敏度及低成本等优势使其有望发展成为一种检测HBV DNA的新方法. 相似文献
133.
Min Bai Feng Chen Xiaowen Cao Yue Zhao Jing Xue Xu Yu Chunhai Fan Yongxi Zhao 《Angewandte Chemie (International ed. in English)》2020,59(32):13267-13272
Tumor progressions such as metastasis are complicated events that involve abnormal expression of different miRNAs and enzymes. Monitoring these biomolecules in live cells with computational DNA nanotechnology may enable discrimination of tumor progression via digital outputs. Herein, we report intracellular entropy‐driven multivalent DNA circuits to implement multi‐bit computing for simultaneous analysis of intracellular telomerase and microRNAs including miR‐21 and miR‐31. These three biomolecules can trigger respective DNA strand displacement recycling reactions for signal amplification. They are visualized by fluorescence imaging, and their signal outputs are encoded as multi‐bit binary codes for different cell types. The results can discriminate non‐tumorigenic, malignant and metastatic breast cells as well as respective tumors. This DNA computing circuit is further performed in a microfluidic chip to differentiate rare co‐cultured cells, which holds a potential for the analysis of clinical samples. 相似文献
134.
重点介绍了近年来国内外在微流控芯片毛细管电泳法用于蛋白质分离分析方面的研究进展。按照分离模式的不同,综述了各种应用于蛋白质分离的微流控芯片毛细管电泳系统,讨论了抑制芯片中的蛋白吸附的各种方法,并展望了芯片毛细管电泳系统在蛋白质分离领域的发展前景。引用文献47篇。 相似文献
135.
以改性C18反相硅胶整体柱为微流控芯片分析系统中固相萃取介质材料, 构建不同功能单元的样品预处理微分析系统, 实现了血清样品中痕量盐酸多巴酚丁胺的富集. 初步构建了单一改性硅胶微柱固相萃取预处理单元, 测试得到了改性硅胶整体柱对血清中痕量盐酸多巴酚丁胺的平均富集倍数为77.2, RSD为12.35%. 为了提高测试的精密度, 进而设计含膜复合式预处理芯片, 探讨了不同预处理单元对血清样品中痕量盐酸多巴酚丁胺富集效率的影响, 优化设计了外接式硅胶整体柱-亲和膜微芯片固相萃取预处理单元, 复合式的反相硅胶整体柱对血清中微量盐酸多巴酚丁胺的平均富集倍数提高到89.4, RSD为4.37%. 结果显示了该预处理单元在血清中痕量药物富集的可行性和有效性. 相似文献
136.
研发了一种多层复合微流控芯片,包含64细胞培养微孔阵列,该微阵列集成了细胞进样、水凝胶三维支架形成和持续灌流培养的过程.以MCF-7乳腺癌细胞为模型,连续培养中监测细胞存活率、细胞密度、增殖率和细胞内pH值,并同时进行冰冻切片后免疫组化染色.实验结果显示,乳腺癌细胞在水凝胶微球中增殖形成了类组织结构.E-cadherin及Vinculin在细胞内、细胞间隙均出现较强表达,提示水凝胶微球中细胞建立了细胞-细胞、细胞-间质连接.芯片上连续培养15天内细胞存活率保持在85%以上,细胞增殖率随时间延长而递减.细胞内pH值检测显示芯片3D培养细胞内部呈现明显的酸化,其程度随着细胞密度增大而增加.这种芯片肿瘤组织微阵列构建方法简单高效,有望发展成为肿瘤研究的有力工具. 相似文献
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138.
Yousef Abdossalami Asl Yadollah Yamini Shahram Seidi Behnam Ebrahimpour 《Analytica chimica acta》2015
In the present research, an effective on chip electromembrane extraction (CEME) coupled with high performance liquid chromatography was presented for analysis of nortriptyline (NOR) and amitriptyline (AMI) as basic model analytes from urine samples. The chip consists of two polymethyl methacrylate (PMMA) parts with two craved microfluidic channels in each part. These channels were used as flow path for the sample solution and a thin compartment for the acceptor phase. A porous polypropylene sheet membrane impregnated with an organic solvent was placed between two parts of chip device to separate the channels. Two platinum electrodes were mounted at the bottom of these channels that were connected to a power supply providing the electrical driving force for migration of ionized analytes from sample solution through the porous sheet membrane into the acceptor phase. This new setup provides effective and reproducible extractions with low volume of sample solution. Efficient parameters on CEME of the model analytes were optimized using one variable at a time method. Under the optimized conditions, the calibration curve was linear in the range of 10.0–500 μg L−1 with coefficient of determination (r2) more than 0.9902. The relative standard deviations (RSDs %) for extraction and determination of the analytes were less than 6.8% based on six replicate measurements. LODs less than 4.0 μg L−1 were obtained for both of the model analytes. The preconcentration factors higher than 17.0-fold were obtained. The results demonstrated that CEME would be used efficiently for extraction and determination of AMI and NOR from urine samples. 相似文献
139.
140.
In this work,a multi-functional analysis platform by coupling a microfluidic chip to a mass spectrometry(MS) detector was described.We constructed a three-dimensional tumor-endothelial co-culture model for simulating drug resistance during tumor treatment.On this specially designed integrated platform,the first step was to prepare heterogeneous cell-encapsulated alginate microcapsules for threedimensional co-culture,and the second step was to achieve on-line perfusion culture and continuous drug stimulation on chip.It facilitates cell proliferation analysis and the collection of metabolism medium.After micro solid phase extraction column(SPE) pretreatment,subsequent mass spectrometry could detect drug metabolism.The high activity of two kinds of cells(A549 and HUVEC) shows the biocompatibility of the platform.Paclitaxel was used as a model drug,the distinctions of drug absorption between the mono-culture group and co-culture group were clearly observed by electrospray ionization quadrupole time-of-flight mass spectrometry(ESI-Q-TOF MS).Therefore,the integrated platform has shown promise as a high throughput,low cost for cell metabolism research and drug screening processes. 相似文献