共查询到19条相似文献,搜索用时 197 毫秒
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单细胞分析对重大疾病的早期诊断等方面有重要意义[1].微流控分析芯片的网络结构和微米级的通道尺寸适合于单细胞进样、溶膜和分离分析.但目前的报道主要集中在细胞培养、计数和筛选[2].我们在十字通道微流控芯片上,通过调节储液池的液面高度和细胞悬液密度,使单细胞逐个通过芯片进样通道和分离通道之间的区域,再结合控制电渗流方向,使单细胞固定在分离通指定位置,然后用电泳缓冲液结合高电场实现细胞快速溶膜,接着进行电泳分离和LIF检测.实现了单个血红细胞内谷胱甘肽(GSH)的高效分离及定量分析. 相似文献
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微流控芯片测定单细胞内化学组分的进展 总被引:1,自引:0,他引:1
细胞是生命的基本单元。由于细胞的个体差异,传统分析群体细胞的方法难以得到单细胞的重要信息。准确可靠地测定单细胞内化学组分的含量能大大提高从正常细胞中辨别不正常细胞的能力,为进一步研究和发展生物化学、医学和临床检验等领域奠定基础。近年来,用微流控芯片进行单细胞分析已引起广泛的兴趣。微流控芯片可以集成单细胞进样、溶膜、电泳分离胞内化学组分和高灵敏度测定等一系列操作步骤,为分析单细胞内的化学组分提供了新的技术平台。本文主要综述了近年来微流控芯片测定单细胞内化学组分的进展。重点在于利用电渗流、压力结合电渗流和激光镊子等技术操控单细胞在微流控芯片上完成单细胞进样、溶膜、细胞内化学组分的电泳分离和高灵敏度测定等一系列操作步骤。对在微流控芯片上的衍生技术也做了较为详细的阐述。 相似文献
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微流控芯片单细胞进样和溶膜 总被引:5,自引:0,他引:5
单细胞分析对重大疾病的早期诊断、治疗和药物筛选以及细胞生理、病理过程的研究有重要意义.将毛细管电泳用于单细胞多组分的测定已取得一些成果,但受毛细管的一维结构限制,单细胞进样和溶膜操作较复杂.微流控分析芯片的网络结构和微米级的通道尺寸使简化单细胞分析成为可能. 相似文献
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Microfluidic device embedding electrodes realizes cell manipulation with the help of dielectrophoresis. Cell manipulation is an important technology for cell sorting and cell population purification. Till now, the theory of dielectrophoresis has been greatly developed. Microfluidic devices with various arrangements of electrodes have been reported from the beginning of the single non‐uniform electric field to the later multiple physical fields. This paper reviews the research status of microfluidic device embedding electrodes for cell manipulation based on dielectrophoresis. Firstly, the working principle of dielectrophoresis is explained. Next, cell manipulation approaches based on dielectrophoresis are introduced. Then, different types of electrode arrangements in the microfluidic device for cell manipulation are discussed, including planar, multilayered and microarray dot electrodes. Finally, the future development trend of the dielectrophoresis with the help of microfluidic devices is prospected. With the rapid development of microfluidic technology, in the near future, high precision, high throughput, high efficiency, multifunctional, portable, economical and practical microfluidic dielectrophoresis will be widely used in the fields of biology, medicine, agriculture and so on. 相似文献
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Wolff A Perch-Nielsen IR Larsen UD Friis P Goranovic G Poulsen CR Kutter JP Telleman P 《Lab on a chip》2003,3(1):22-27
The integration of complete analyses systems "on chip" is one of the great potentials of microfabricated devices. In this study we present a new pressure-driven microfabricated fluorescent-activated cell sorter chip with advanced functional integration. Using this sorter, fluorescent latex beads are sorted from chicken red blood cells, achieving substantial enrichments at a sample throughput of 12000 cells s(-1). As a part of the sorter chip, we have developed a monolithically integrated single step coaxial flow compound for hydrodynamic focusing of samples in flow cytometry and cell sorting. The structure is simple, and can easily be microfabricated and integrated with other microfluidic components. We have designed an integrated chamber on the chip for holding and culturing of the sorted cells. By integrating this chamber, the risk of losing cells during cell handling processes is eliminated. Furthermore, we have also developed integrated optics for cell detection. Our new design contributes to the ongoing efforts for building a fully integrated micro cell sorting and analysing system. 相似文献
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D Baigl 《Lab on a chip》2012,12(19):3637-3653
Using light to control liquid motion is a new paradigm for the actuation of microfluidic systems. We review here the different principles and strategies to induce or control liquid motion using light, which includes the use of radiation pressure, optical tweezers, light-induced wettability gradients, the thermocapillary effect, photosensitive surfactants, the chromocapillary effect, optoelectrowetting, photocontrolled electroosmotic flows and optical dielectrophoresis. We analyze the performance of these approaches to control using light many kinds of microfluidic operations involving discrete pL- to μL-sized droplets (generation, driving, mixing, reaction, sorting) or fluid flows in microchannels (valve operation, injection, pumping, flow rate control). We show that a complete toolbox is now available to control microfluidic systems by light. We finally discuss the perspectives of digital optofluidics as well as microfluidics based on all optical fluidic chips and optically reconfigurable devices. 相似文献
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Rupert S. W. Thomas Peter D. Mitchell Richard O. C Oreffo Hywel Morgan Nicolas G. Green 《Electrophoresis》2019,40(20):2718-2727
Microelectrode arrays are used to sort single fluorescently labeled cells and particles as they flow through a microfluidic channel using dielectrophoresis. Negative dielectrophoresis is used to create a “Dielectrophoretic virtual channel” that runs along the center of the microfluidic channel. By switching the polarity of the electrodes, the virtual channel can be dynamically reconfigured to direct particles along a different path. This is demonstrated by sorting particles into two microfluidic outlets, controlled by an automated system that interprets video data from a color camera and makes complex sorting decisions based on color, intensity, size, and shape. This enables the rejection of particle aggregates and other impurities, and the system is optimized to isolate high purity populations from a heterogeneous sample. Green beads are isolated from an excess of red beads with 100% purity at a rate of up to 0.9 particles per second, in addition application to the sorting of osteosarcoma and human bone marrow cells is evidenced. The extension of Dielectrophoretic Virtual Channels to an arbitrary number of sorting outputs is examined, with design, simulation, and experimental verification of two alternate geometries presented and compared. 相似文献
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Wenlai Tang Di Jiang Zongan Li Liya Zhu Jianping Shi Jiquan Yang Nan Xiang 《Electrophoresis》2019,40(6):930-954
Microfluidic technologies for isolating cells of interest from a heterogeneous sample have attracted great attentions, due to the advantages of less sample consumption, simple operating procedure, and high separation accuracy. According to the working principles, the microfluidic cell sorting techniques can be categorized into biochemical (labeled) and physical (label‐free) methods. However, the inherent drawbacks of each type of method may somehow influence the popularization of these cell sorting techniques. Using the multiple complementary isolation principles is a promising strategy to overcome this problem, therefore there appears to be a continuing trend to integrate two or more sorting methods together. In this review, we focus on the recent advances in microfluidic cell sorting techniques relied on both physical and biochemical principles, with emphasis on the mechanisms of cell separation. The biochemical cell sorting techniques enhanced by physical principles and the physical cell sorting techniques enhanced by biochemical principles, are first introduced. Then, we highlight on‐chip magnetic‐activated cell sorting, on‐chip fluorescence‐activated cell sorting, multi‐step cell sorting and multi‐principle cell sorting techniques, which are based on both physical and biochemical separation mechanisms. Finally, the challenges and future perspectives of the integrated microfluidics for cell sorting are discussed. 相似文献
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The composition of the ship's ballast water is complex and contains a large number of microalgae cells, bacteria, microplastics, and other microparticles. To increase the accuracy and efficiency of detection of the microalgae cells in ballast water, a new microfluidic chip for continuous separation of microalgae cells based on alternating current dielectrophoresis was proposed. In this microfluidic chip, one piece of 3‐dimensional electrode is embedded on one side and eight discrete electrodes are arranged on the other side of the microchannel. An insulated triangular structure between electrodes is designed for increasing the inhomogeneity of the electric field distribution and enhancing the dielectrophoresis (DEP) force. A sheath flow is designed to focus the microparticles near the electrode, so as to increase the suffered DEP force and improve separation efficiency. To demonstrate the performance of the microfluidic separation chip, we developed two species of microalgae cells (Platymonas and Closterium) and a kind of microplastics to be used as test samples. Analyses of the related parameters and separation experiments by our designed microfluidic chip were then conducted. The results show that the presented method can separate the microalgae cells from the mixture efficiently, and this is the first time to separate two or more species of microalgae cells in a microfluidic chip by using negative and positive DEP force simultaneously, and moreover it has some advantages including simple operation, high efficiency, low cost, and small size and has great potential in on‐site pretreatment of ballast water. 相似文献
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Sorting (or isolation) and manipulation of rare cells with high recovery rate and purity are of critical importance to a wide range of physiological applications. In the current paper, we report on a generic single cell manipulation tool that integrates optical tweezers and microfluidic chip technologies for handling small cell population sorting with high accuracy. The laminar flow nature of microfluidics enables the targeted cells to be focused on a desired area for cell isolation. To recognize the target cells, we develop an image processing methodology with a recognition capability of multiple features, e.g., cell size and fluorescence label. The target cells can be moved precisely by optical tweezers to the desired destination in a noninvasive manner. The unique advantages of this sorter are its high recovery rate and purity in small cell population sorting. The design is based on dynamic fluid and dynamic light pattern, in which single as well as multiple laser traps are employed for cell transportation, and a recognition capability of multiple cell features. Experiments of sorting yeast cells and human embryonic stem cells are performed to demonstrate the effectiveness of the proposed cell sorting approach. 相似文献
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Yong-Jiang Li Wen-Jia Zhang Chen-Lin Zhan Ke-Jie Chen Chun-Dong Xue Yu Wang Xiao-Ming Chen Kai-Rong Qin 《Electrophoresis》2021,42(21-22):2264-2272
Biological cells in vivo typically reside in a dynamic flowing microenvironment with extensive biomechanical and biochemical cues varying in time and space. These dynamic biomechanical and biochemical signals together act to regulate cellular behaviors and functions. Microfluidic technology is an important experimental platform for mimicking extracellular flowing microenvironment in vitro. However, most existing microfluidic chips for generating dynamic shear stress and biochemical signals require expensive, large peripheral pumps and external control systems, unsuitable for being placed inside cell incubators to conduct cell biology experiments. This study has developed a microfluidic generator of dynamic shear stress and biochemical signals based on autonomously oscillatory flow. Further, based on the lumped-parameter and distributed-parameter models of multiscale fluid dynamics, the oscillatory flow field and the concentration field of biochemical factors has been simulated at the cell culture region within the designed microfluidic chip. Using the constructed experimental system, the feasibility of the designed microfluidic chip has been validated by simulating biochemical factors with red dye. The simulation results demonstrate that dynamic shear stress and biochemical signals with adjustable period and amplitude can be generated at the cell culture chamber within the microfluidic chip. The amplitudes of dynamic shear stress and biochemical signals is proportional to the pressure difference and inversely proportional to the flow resistance, while their periods are correlated positively with the flow capacity and the flow resistance. The experimental results reveal the feasibility of the designed microfluidic chip. Conclusively, the proposed microfluidic generator based on autonomously oscillatory flow can generate dynamic shear stress and biochemical signals without peripheral pumps and external control systems. In addition to reducing the experimental cost, due to the tiny volume, it is beneficial to be integrated into cell incubators for cell biology experiments. Thus, the proposed microfluidic chip provides a novel experimental platform for cell biology investigations. 相似文献
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Park K Jang J Irimia D Sturgis J Lee J Robinson JP Toner M Bashir R 《Lab on a chip》2008,8(7):1034-1041
The size of a cell is a fundamental physiological property and is closely regulated by various environmental and genetic factors. Optical or confocal microscopy can be used to measure the dimensions of adherent cells, and Coulter counter or flow cytometry (forward scattering light intensity) can be used to estimate the volume of single cells in a flow. Although these methods could be used to obtain the mass of single live cells, no method suitable for directly measuring the mass of single adherent cells without detaching them from the surface is currently available. We report the design, fabrication, and testing of 'living cantilever arrays', an approach to measure the mass of single adherent live cells in fluid using silicon cantilever mass sensor. HeLa cells were injected into microfluidic channels with a linear array of functionalized silicon cantilevers and the cells were subsequently captured on the cantilevers with positive dielectrophoresis. The captured cells were then cultured on the cantilevers in a microfluidic environment and the resonant frequencies of the cantilevers were measured. The mass of a single HeLa cell was extracted from the resonance frequency shift of the cantilever and was found to be close to the mass value calculated from the cell density from the literature and the cell volume obtained from confocal microscopy. This approach can provide a new method for mass measurement of a single adherent cell in its physiological condition in a non-invasive manner, as well as optical observations of the same cell. We believe this technology would be very valuable for single cell time-course studies of adherent live cells. 相似文献