共查询到18条相似文献,搜索用时 343 毫秒
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癌症作为常见病正严重威胁着我国乃至全球居民的健康。循环肿瘤细胞(CTCs)是一类由癌变部位释放并进入血液中的癌细胞,其在癌症的早期诊断、个体化及肿瘤转移机制研究等方面的作用正逐渐被发现和认可,但由于血液中的CTCs含量极少,对其分选极具挑战。微流控芯片作为一种微型化、高通量、集成化平台,在CTCs研究中彰显了独特的优势,相关报道也越来越多。随着研究的深入,微流控芯片技术不再局限于基于模型样品的方法学开发,而是更注重于能否用于临床实际样品中CTCs的检测,但目前未见该角度的综述报道。为此,文章综述了近年来用于临床实际样品CTCs分析的微流控芯片分选技术,并探讨了微流控芯片用于CTCs分选的发展趋势。 相似文献
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循环肿瘤细胞(CTCs)出现于癌症患者的外周血中,是一种重要的游离态组织样本,对于癌症的早期诊断和预后评估具有非常重要的临床诊断价值。由于血液中CTCs含量极少,对其进行分选富集是CTCs检测和分析的一个重要预处理步骤。传统的宏观方法虽然也能实现细胞分离,但存在耗时长、样品需求量大、目标细胞损失严重及硬件设备依赖性高等不足。近年来兴起的微流控技术可在微米尺度范围内集成物理、化学及生物手段,易于实现整体器件的微型化和低成本便携式发展,为稀有CTCs的高灵敏度、高效分选提供重要的潜在技术手段。本文综述了微流控技术实现CTCs分选的最新研究进展,详细阐述了各种被动、主动分选方法的原理及成功应用实例,分析各方法的优缺点,提出一种新型的多级分选芯片结构,并最后探讨了微流控CTCs分选芯片在临床应用中面临的挑战及未来的发展趋势。 相似文献
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液滴微流控系统是微流控芯片领域的一个新的分支,由于其诸多独特的优势而得到了广泛的研究和报道。本文对液滴的制备和相关的操控技术,包括液滴的分裂、融合、混合、分选、存储和编码等进行了介绍,对液滴技术近年来在化学与生物化学分析等领域中的应用进行了综述,并展望了液滴微流控技术的发展前景。 相似文献
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惯性效应在微流控芯片中的应用 总被引:3,自引:0,他引:3
作为一种操控粒子或流体的新技术,基于流体惯性的操控技术已被应用于微流控芯片中粒子的输运、分选、聚焦及试样的混合和反应等操作,而在微尺度惯性效应基础上的惯性微流控芯片由于具有高通量、无需外场介入、低成本、易集成及微型化等众多优点,可用于解决医疗诊断、生化分析、合成化学及环境监测等领域的检测分析和微量操控问题,因此对该技术的机理及应用研究已成为目前微流控技术领域一个重要的研究热点。本文在介绍惯性微流控芯片机理及其研究进展的同时,从惯性聚焦、惯性分选及基于Dean流的微混合器和微流控光学器件等几个方面对惯性微流控芯片的最新应用研究进展进行了较为详细的介绍和分析比较。在此基础上,分析了惯性微流控芯片的局限和未来需要解决的问题。 相似文献
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3D打印微流控芯片技术研究进展 总被引:2,自引:0,他引:2
近年来,微流控技术在生命科学和医学诊断等领域得到广泛的应用,显示出了其在检测速度、精度以及试剂损耗等方面相比传统方法的显著优势.然而,使用从半导体加工技术继承而来的微加工技术制作微流控芯片具有比较高的资金和技术门槛,在一定程度上阻碍了微流控技术的推广和应用.近年来随着3D打印技术的兴起,越来越多的研究者尝试使用3D打印技术加工微流控芯片.相比于传统的微加工技术,3D打印微流控芯片技术显示出了其设计加工快速、材料适应性广、成本低廉等优势.本文针对近年来国内外在3D打印微流控芯片领域的最新进展进行了综述,着重介绍了采用微立体光刻、熔融沉积成型以及喷墨打印等3D打印技术加工制作微流控芯片的方法,以及这些微流控芯片在分析化学、生命科学、医学诊断等领域的应用,并对3D打印微流控芯片技术未来的发展进行了展望. 相似文献
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用合适的手段表征生物分子的相互作用对于深刻理解生命过程的本质以及进行医药开发都具有重要意义。将微流控芯片和毛细管电泳相结合的微流控芯片电泳技术具有快速、高效、高通量、样品用量少和易于整合等诸多优势。本文对近年来进行生物分子间相互作用结合常数测定以及结合动力学研究的微流控芯片电泳分离模式、分析方法和芯片检测方法分别做了介绍;简单对比了微流控芯片技术和微阵列生物芯片生物分子间相互作用研究技术;最后分析了微流控芯片技术目前的不足,并对其未来的发展进行了展望。 相似文献
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Florina S. Iliescu Wen Jing Sim Hossein Heidari Daniel P. Poenar Jianmin Miao Hayden K. Taylor Ciprian Iliescu 《Electrophoresis》2019,40(10):1457-1477
Circulating tumor cells (CTCs) play an essential role in the metastasis of tumors, and thus can serve as a valuable prognostic factor for malignant diseases. As a result, the ability to isolate and characterize CTCs is essential. This review underlines the potential of dielectrophoresis for CTCs enrichment. It begins by summarizing the key performance parameters and challenges of CTCs isolation using microfluidics. The two main categories of CTCs enrichment—affinity‐based and label‐free methods—are analysed, emphasising the advantages and disadvantages of each as well as their clinical potential. While the main argument in favour of affinity‐based methods is the strong specificity of CTCs isolation, the major advantage of the label‐free technologies is in preserving the integrity of the cellular membrane, an essential requirement for downstream characterization. Moving forward, we try to answer the main question: “What makes dielectrophoresis a method of choice in CTCs isolation?” The uniqueness of dielectrophoretic CTCs enrichment resides in coupling the specificity of the isolation process with the conservation of the membrane surface. The specificity of the dielectrophoretic method stems from the differences in the dielectric properties between CTCs and other cells in the blood: the capacitances of the malignantly transformed cellular membranes of CTCs differ from those of other cells. Examples of dielectrophoretic devices are described and their performance evaluated. Critical requirements for using dielectrophoresis to isolate CTCs are highlighted. Finally, we consider that DEP has the potential of becoming a cytometric method for large‐scale sorting and characterization of cells. 相似文献
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Pinched flow coupled shear-modulated inertial microfluidics for high-throughput rare blood cell separation 总被引:1,自引:0,他引:1
Blood is a highly complex bio-fluid with cellular components making up >40% of the total volume, thus making its analysis challenging and time-consuming. In this work, we introduce a high-throughput size-based separation method for processing diluted blood using inertial microfluidics. The technique takes advantage of the preferential cell focusing in high aspect-ratio microchannels coupled with pinched flow dynamics for isolating low abundance cells from blood. As an application of the developed technique, we demonstrate the isolation of cancer cells (circulating tumor cells (CTCs)) spiked in blood by exploiting the difference in size between CTCs and hematologic cells. The microchannel dimensions and processing parameters were optimized to enable high throughput and high resolution separation, comparable to existing CTC isolation technologies. Results from experiments conducted with MCF-7 cells spiked into whole blood indicate >80% cell recovery with an impressive 3.25 × 10(5) fold enrichment over red blood cells (RBCs) and 1.2 × 10(4) fold enrichment over peripheral blood leukocytes (PBL). In spite of a 20× sample dilution, the fast operating flow rate allows the processing of ~10(8) cells min(-1) through a single microfluidic device. The device design can be easily customized for isolating other rare cells from blood including peripheral blood leukocytes and fetal nucleated red blood cells by simply varying the 'pinching' width. The advantage of simple label-free separation, combined with the ability to retrieve viable cells post enrichment and minimal sample pre-processing presents numerous applications for use in clinical diagnosis and conducting fundamental studies. 相似文献
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Circulating tumor cells (CTCs) have been proven to have significant prognostic, diagnostic, and clinical values in early-stage cancer detection and treatment. The efficient separation of CTCs from peripheral blood can ensure intact and viable CTCs and can, thus, give proper genetic characterization and drug innovation. In this study, continuous and high-throughput separation of MDA-231 CTCs from overlapping sized white blood cells (WBCs) is achieved by modifying inertial cell focusing with dielectrophoresis (DEP) in a single-stage microfluidic platform by numeric simulation. The DEP is enabled by embedding interdigitated electrodes with alternating field control on a serpentine microchannel to avoid creating two-stage separation. Rather than using the electrokinetic migration of cells which slows down the throughput, the system leverages the inertial microfluidic flow to achieve high-speed continuous separation. The cell migration and cell positioning characteristics are quantified through coupled physics analyses to evaluate the effects of the applied voltages and Reynolds numbers (Re) on the separation performance. The results indicate that the introduction of DEP successfully migrates WBCs away from CTCs and that separation of MDA-231 CTCs from similar sized WBCs at a high Re of 100 can be achieved with a low voltage of magnitude 4 ×106 V/m. Additionally, the viability of MDA-231 CTCs is expected to be sustained after separation due to the short-term DEP exposure. The developed technique could be exploited to design active microchips for high-throughput separation of mixed cell beads despite their significant size overlap, using DEP-modified inertial focusing controlled simply by adjusting the applied external field. 相似文献
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Over the past decade a tremendous amount of research has been performed using microfluidic analytical devices to detect over 200 different chemical species. Most of this work has involved substantial integration of fluid manipulation components such as separation channels, valves, and filters. This level of integration has enabled complex sample processing on miniscule sample volumes. Such devices have also demonstrated high throughput, sensitivity, and separation performance. Although the miniaturization of fluidics has been highly valuable, these devices typically rely on conventional ancillary equipment such as power supplies, detection systems, and pumps for operation. This auxiliary equipment prevents the full realization of a "lab-on-a-chip" device with complete portability, autonomous operation, and low cost. Integration and/or miniaturization of ancillary components would dramatically increase the capability and impact of microfluidic separations systems. This review describes recent efforts to incorporate auxiliary equipment either as miniaturized plug-in modules or directly fabricated into the microfluidic device. 相似文献
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Qin Tu Long Pang Yanrong Zhang Maoseng Yuan Jianchun Wang Dongen Wang Wenming Liu Jinyi Wang 《中国化学》2013,31(3):304-316
Microfluidic devices, as a new miniaturized platform stemming from the field of micro-electromechanical sys-tems, have been used in many disciplines. In the field of chemical reactions, microfluidic device-based microreac-tors have shown great promise in building new chemical technologies and processes with increased speed and reli- ability and reduced sample consumption and cost. This technology has also become a new and effective tool for precise, high-throughput, and automatic analysis of chemical synthesis processes. Compared with conventional chemical laboratory batch methodologies, microfluidic reactors have a number of features, such as high mixing ef- ficiency, short reaction time, high heat-transfer coefficient, small reactant volume, controllable residence time, and high surface-to-volume ratio, among others. Combined with recent advances in microfluidic devices for chemical reactions, this review aims to give an overview of the features and applications of microfluidic devices in the field of chemical synthesis. It also aims to stimulate the development of microfluidic device applications in the field of chemical reactions. 相似文献
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The prognosis of malignant tumors is challenged by insufficient means to effectively detect tumors at early stage. Liquid biopsy using circulating tumor cells (CTCs) as biomarkers demonstrates a promising solution to tackle the challenge, because CTCs play a critical role in cancer metastatic process via intravasation, circulation, extravasation, and formation of secondary tumor. However, the effectiveness of the solution is compromised by rarity, heterogeneity, and vulnerability associated with CTCs. Among a plethora of novel approaches for CTC isolation and enrichment, microfluidics leads to isolation and detection of CTCs in a cost-effective and operation-friendly way. Development of microfluidics also makes it feasible to model the cancer metastasis in vitro using a microfluidic system to mimick the in vivo microenvironment, thereby enabling analysis and monitor of tumor metastasis. This paper aims to review the latest advances for exploring the dual-roles microfluidics has played in early cancer diagnosis via CTC isolation and investigating the role of CTCs in cancer metastasis; the merits and drawbacks for dominating microfluidics-based CTC isolation methods are discussed; biomimicking cancer metastasis using microfluidics are presented with example applications on modelling of tumor microenvironment, tumor cell dissemination, tumor migration, and tumor angiogenesis. The future perspectives and challenges are discussed. 相似文献
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The development of early and personalized diagnostic protocol with rapid response and high accuracy is considered the most promising avenue to advance point-of-care testing for tumor diagnosis and therapy. Given the growing awareness of the limitations of conventional tissue biopsy for gathering tumor information, considerable interest has recently been aroused in liquid biopsy. Among a myriad of analytical approaches proposed for liquid biopsy, microfluidics-based separation and purification techniques possess merits of high throughput, low samples consumption, high flexibility, low cost, high sensitivity, automation capability and enhanced spatio-temporal control. These characteristics endow microfluidics to serve as an emerging and promising tool in tumor diagnosis and prognosis by identifying specific circulating tumor biomarkers. In this review, we will put our focus on three key categories of circulating tumor biomarkers, namely, circulating tumor cells (CTCs), circulating exosomes, and circulating nucleic acids (cNAs), and discuss the significant roles of microfluidics in the separation and analysis of circulating tumor biomarkers. Recent advances in microfluidic separation and analysis of CTCs, exosomes, and cNAs will be highlighted and tabulated. Finally, the current challenges and future niches of using microfluidic techniques in the separation and analysis of circulating tumor biomarkers will be discussed. 相似文献
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Isolation of plasma from whole blood using planar microfilters for lab-on-a-chip applications 总被引:1,自引:0,他引:1
Researchers are actively developing devices for the microanalysis of complex fluids, such as blood. These devices have the potential to revolutionize biological analysis in a manner parallel to the computer chip by providing very high throughput screening of complex samples and massively parallel bioanalytical capabilities. A necessary step performed in clinical chemistry is the isolation of plasma from whole blood, and effective sample preparation techniques are needed for the development of miniaturized clinical diagnostic devices. This study demonstrates the use of passive, operating entirely on capillary action, transverse-flow microfilter devices for the microfluidic isolation of plasma from whole blood. Using these planar microfilters, blood can be controllably fractionated with minimal cell lysis. A characterization of the device performance reveals that plasma filter flux is dependent upon the wall shear rate of blood in the filtration channel, and this result is consistent with macroscale blood filtration using microporous membranes. Also, an innovative microfluidic layout is demonstrated that extends device operation time via capillary action from seconds to minutes. Efficiency of these microfilters is approximately three times higher than the separation efficiencies predicted for microporous membranes under similar conditions. As such, the application of the microscale blood filtration designs used in this study may have broad implications in the design of lab-on-a-chip devices, as well as the field of separation science. 相似文献