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1.
    
We developed a low-cost multi-core inertial microfluidic centrifuge (IM-centrifuge) to achieve a continuous-flow cell/particle concentration at a throughput of up to 20 mL/min. To lower the cost of our IM-centrifuge, we clamped a disposable multilayer film-based inertial microfluidic (MFIM) chip with two reusable plastic housings. The key MFIM chip was fabricated in low-cost materials by stacking different polymer-film channel layers and double-sided tape. To increase processing throughput, multiplexing spiral inertial microfluidic channels were integrated within an all-in-one MFIM chip, and a novel sample distribution strategy was employed to equally distribute the sample into each channel layer. Then, we characterized the focusing performance in the MFIM chip over a wide flow-rate range. The experimental results showed that our IM-centrifuge was able to focus various-sized particles/cells to achieve volume reduction. The sample distribution strategy also effectively ensured identical focusing and concentration performances in different cores. Finally, our IM-centrifuge was successfully applied to concentrate microalgae cells with irregular shapes and highly polydisperse sizes. Thus, our IM-centrifuge holds the potential to be employed as a low-cost, high-throughput centrifuge for disposable use in low-resource settings.  相似文献   

2.
    
We report here a low-cost, rapid-prototyping, and beehive-like multilayer polymer microfluidic device for ultrahigh-throughput blood plasma separation. To understand the device physics and optimize the device structure, the effect of cross-sectional dimension and operational parameter on particle focusing behavior was explored using a single spiral microchannel device. Then, the blood plasma separation performance of the determined channel structure was validated using the blood samples with different hematocrits (HCTs). It was found that a high separation efficiency of 99% could be achieved using the blood sample with an HCT of 0.5% at a high throughput of 1 mL/min. Finally, a multilayer microfluidic device with a novel beehive-like multiplexing channel arrangement was developed for ultrahigh-throughput blood plasma separation. The prototype device could be fabricated within ∼1 hour utilizing the laser cutting and thermal lamination methods. The total processing throughput could reach up to 72 mL/min for 0.5% HCT sample with a plasma separation ratio close to 90%. Our device may hold potentials for the ultrahigh-throughput separation of blood plasma from large volume blood samples for downstream disease diagnosis.  相似文献   

3.
    
Inertial microfluidics has attracted significant attentions in last decade due to its superior advantages of high throughput, label- and external field-free operation, simplicity, and low cost. A wide variety of channel geometry designs were demonstrated for focusing, concentrating, isolating, or separating of various bioparticles such as blood components, circulating tumor cells, bacteria, and microalgae. In this review, we first briefly introduce the physics of inertial migration and Dean flow for allowing the readers with diverse backgrounds to have a better understanding of the fundamental mechanisms of inertial microfluidics. Then, we present a comprehensive review of the recent advances and applications of inertial microfluidic devices according to different channel geometries ranging from straight channels, curved channels to contraction-expansion-array channels. Finally, the challenges and future perspective of inertial microfluidics are discussed. Owing to its superior benefit for particle manipulation, the inertial microfluidics will play a more important role in biology and medicine applications.  相似文献   

4.
    
We developed a low-cost polymer-film spiral inertial microfluidic device for the effective size-dependent separation of malignant tumor cells. The device was fabricated in polymer films by rapid laser cutting and chemical bonding. After fabricating the prototype device, the separation performance of our device was evaluated using particles and cells. The effects of operational flow rate, cell diameter, and cell concentration on the separation performance were explored. Our device successfully separated tumor cells from polydisperse white blood cells according to their different migration modes and lateral positions. Then, the separation of rare cells was carried out using the high-concentration lysed blood spiked with 200 tumor cells. Experimental results showed that 83.90% of the tumor cells could be recovered, while 99.87% of white blood cells could be removed. We successfully employed our device for processing clinical pleural effusion samples from patients with advanced metastatic breast cancer. Malignant tumor cells with an average purity of 2.37% could be effectively enriched, improving downstream diagnostic accuracy. Our device offers the advantages of label-free operation, low cost, and fast fabrication, thus being a potential tool for effective cell separation.  相似文献   

5.
By exploiting its ability to play sounds, a mobile phone with suitable software installed can serve the basic functions of a potentiostat in controlling an applied potential to oxidise ECL-active molecules, while the resultant photonic signal is monitored using the camera in video mode. In combination with paper microfluidic sensors this opens significant new possibilities for low-cost, instrument-free sensing.  相似文献   

6.
By exploiting its ability to play sounds, a mobile phone with suitable software installed can serve the basic functions of a potentiostat in controlling an applied potential to oxidise ECL-active molecules, while the resultant photonic signal is monitored using the camera in video mode. In combination with paper microfluidic sensors this opens significant new possibilities for low-cost, instrument-free sensing.  相似文献   

7.
    
Early detection of pathogenic microorganisms is pivotal to diagnosis and prevention of health and safety crises. Standard methods for pathogen detection often rely on lengthy culturing procedures, confirmed by biochemical assays, leading to >24 h for a diagnosis. The main challenge for pathogen detection is their low concentration within complex matrices. Detection of blood-borne pathogens via techniques such as PCR requires an initial positive blood culture and removal of inhibitory blood components, reducing its potential as a diagnostic tool. Among different label-free microfluidic techniques, inertial focusing on microscale channels holds great promise for automation, parallelization, and passive continuous separation of particles and cells. This work presents inertial microfluidic manipulation of small particles and cells (1–10 μm) in curved serpentine glass channels etched at different depths (deep and shallow designs) that can be exploited for (1) bacteria preconcentration from biological samples and (2) bacteria-blood cell separation. In our shallow device, the ability to focus Escherichia coli into the channel side streams with high recovery (89% at 2.2× preconcentration factor) could be applied for bacteria preconcentration in urine for diagnosis of urinary tract infections. Relying on differential equilibrium positions of red blood cells and E. coli inside the deep device, 97% red blood cells were depleted from 1:50 diluted blood with 54% E. coli recovered at a throughput of 0.7 mL/min. Parallelization of such devices could process relevant volumes of 7 mL whole blood in 10 min, allowing faster sample preparation for downstream molecular diagnostics of bacteria present in bloodstream.  相似文献   

8.
何天稀  梁琼麟  王九  罗国安 《化学进展》2018,30(11):1734-1748
脂质体在药物输送、人造细胞等许多领域有着巨大的应用前景。作为药物载体,脂质体可以保护药物、提高药效、减小药物对机体的毒性、使药物具有靶向性,因此发展或改进脂质体制备方法有着重要的意义。然而,传统的脂质体制备存在耗时长、设备贵、制备条件易变、前后处理步骤多、粒径不均一以及难重复等问题,基于此,脂质体的微流控制备技术逐渐发展起来。研究表明微流控技术在脂质体制备方面有着独特的优势,包括精确地控制脂质体的大小和尺寸分布。本文综述了近年来基于微流控技术的几种脂质体制备方法的研究进展,并对比了几种方法制备的脂质体的性质;进一步分析和探讨了当前微流控技术制备脂质体存在的问题,并展望了其发展趋势和方向。  相似文献   

9.
    
Precise and reliable liquid delivery is vital for microfluidic applications. Here, we illustrate the design, fabrication, characterization, and application of a portable, low cost, and robust micropump, which brings solution to stable liquid delivery in microfluidic environment. The pump is designed with three optional speeds of different pumping flow rates, and it can be simply actuated by spring‐driven mechanism. The different flow rates of the pump are realized via passive microvalves in a compact microfluidic chip, which is installed in the pump. Importantly, the membrane structures of the microvalves allow accurate liquid control, and stable flow rates can be achieved via a spring setup. The proposed pump is applied to continuously and stably infuse microbead suspension into an inertial microfluidic chip, and good particle focusing is realized in the spiral channel of the inertial microfluidic chip. The proposed portable, self‐powered, and cost‐efficient pump is crucial for microfluidic lab‐on‐a‐chip system integration, which may facilitate microfluidic application for precise liquid delivery, control, measurement, and analysis.  相似文献   

10.
纸芯片微流控技术的发展及应用   总被引:1,自引:0,他引:1  
纸芯片微流控技术是一种新型微流控技术。相比于以玻璃、石英、高聚物等为基底的传统微流控芯片,纸芯片具有成本低、易操作、可携带、耗样量小等优点。该文介绍了纸芯片的发展及常用的制作方法,并举例说明了光度法、荧光法、化学发光及电化学发光法和电化学法在纸芯片检测中的应用;归纳了纸芯片技术在临床诊断、环境监控以及食品安全分析等方面的应用;最后对纸芯片微流控的应用前景进行了展望。  相似文献   

11.
LI  Gang  GE  Shuli  NI  Xiaofang  DONG  Shuqing  WANG  Qingjiang  HE  Pingang  FANG  Yuzhi 《中国化学》2009,27(11):2207-2211
Copolymers of poly(vinylpyrrolidone) (PVP) and hydroxyethylcellulose (HEC) were synthesized, with PVP to HEC molar ratios of 3:1, 2:1 and 1:1. The copolymers were tested as separation media in DNA fragment separation analysis by microchip electrophoresis (MCE). Separation efficiency over 3.8×105 for 118 bp has been reached by using the bare channels without the additional polymer coating step. Under optimized separation conditions for longer read length DNA sequencing, the separation ability of the copolymers decreased with decreasing (PVP‐co‐HEC) molar ratio from 3:1 to 2:1 and 1:1. In comparison with (PVP‐co‐HEC) 1:1, the copolymer with (PVP‐co‐HEC) 3:1 ratio showed high separation efficiency. By using a 20 g·L?1 copolymer with (PVP‐co‐HEC) 3:1 ratio, ΦΧ174‐HaeIII digest DNA marker was successfully separated within 3 min.  相似文献   

12.
    
A passive microfluidic device is reported for continuous microparticle enrichment. The microparticle is enriched based on the inertial effect in a microchannel with contracting‐expanding structures on one side where microparticles/cells are subjected to the inertial lift force and the momentum‐change‐induced inertial force induced by highly curved streamlines. Under the combined effect of the two forces, yeast cells and microparticles of different sizes were continuously focused in the present device over a range of Reynolds numbers from 16.7 to 125. ~68% of the particle‐free liquid was separated from the sample at Re = 66.7, and ~18 μL particle‐free liquid was fast obtained within 10 s. Results also showed that the geometry of the contracting‐expanding structure significantly influenced the lateral migration of the particle. Structures with a large angle induced strong inertial effect and weak disturbance effect of vortex on the particle, both of which enhanced the microparticle enrichment in microchannel. With simple structure, small footprint (18 × 0.35 mm), easy operation and cell‐friendly property, the present device has great potential in biomedical applications, such as the enrichment of cells and the fast extraction of plasma from blood for disease diagnose and therapy.  相似文献   

13.
    
Point-of-care diagnostics requires a smart separation of particles and/or cells. In this work, the multiorifice fluid fractionation as a passive method and dielectrophoresis-based actuator as an active tool are combined to offer a new device for size-based particle separation. The main objective of the combination of these two well-established techniques is to improve the performance of the multiorifice fluid fractionation by taking advantage of dielectrophoresis-based actuator for separating particles. Initially, by using numerical simulations, the effect of using dielectrophoresis-based actuator in multiorifice fluid fractionation on the separation of particles was investigated, and the size of the device was optimized by 25% compared to a device without dielectrophoresis-based actuator. Also, adding dielectrophoresis-based actuator to multiorifice fluid fractionation can extend the range of flow rates needed for separation. In the absence of dielectrophoresis-based actuator, the separation took place only when the flow rate is 100 μL/min, in the presence of dielectrophoresis-based actuator (20 Vp-p), the separation happened in flow rates ranging from 70 to 120 μL/min.  相似文献   

14.
    
Microfluidic separation of particles and cells is crucial to lab-on-a-chip applications in the fields of science, engineering, and industry. The continuous-flow separation methods can be classified as active or passive depending on whether the force involved in the process is externally imposed or internally induced. The majority of current separations have been realized using only one of the active or passive methods. Such a single-mode process is usually limited to one-parameter separation, which often becomes less effective or even ineffective when dealing with real samples because of their inherent heterogeneity. Integrating two or more separation methods of either type has been demonstrated to offer several advantages like improved specificity, resolution, and throughput. This article reviews the recent advances of such multimode particle and cell separations in microfluidic devices, including the serial-mode prefocused separation, serial-mode multistage separation, and parallel-mode force-tuned separation.  相似文献   

15.
陈雯雯  甘忠桥  秦建华 《色谱》2021,39(9):968-980
外泌体是一类由细胞分泌的含有脂质、蛋白、核酸等多种物质的纳米级囊泡,主要参与细胞间的物质交换及信息传导,与多种疾病的发生发展密切相关。对外泌体进行深入研究,理解其生物学功能,对疾病诊断与治疗具有重要意义。由于外泌体尺寸较小且密度和体液接近,想要对复杂生物样本中的外泌体进行分离与分析十分困难。传统的外泌体分离方法如超速离心、超滤等大都需要借助大型仪器设备,且耗时长、操作复杂。因此迫切需要开发高效、便捷的外泌体分离检测手段。微流控技术因其微型化、高通量、可集成等特点,为外泌体的分离分析提供了一个新的平台。该文主要对近年来微流控技术在外泌体分离分析相关领域的研究进展进行了综述。重点从外泌体物理特性和生化特性两个角度出发,介绍了微流控芯片技术用于外泌体分离领域的主要原理、策略和方法。此外,还介绍了微流控技术与荧光、电化学传感、表面等离子体共振等多模态检测方法结合,实现外泌体一体化分析的新进展。最后,该文分析了目前微流控技术用于外泌体分离检测存在的挑战,并对其发展趋势和前景进行了展望。随着微流控外泌体分离分析装置的不断微型化、集成化、自动化,微流控芯片技术将在外泌体分离、生化检测、机制研究等方面将发挥越来越重要的作用。  相似文献   

16.
The flow field-flow fractionation (FIFFF) technique is a promising method for separating and analysing particles and large size macromolecules from a few nanometers to approximately 50 μm. A new fractionation channel is described featuring well defined flow conditions even for low channel heights with convenient assembling and operations features. The application of the new flow field-flow fractionation channel is proved by the analysis of pigments and other small particles of technical interest in the submicrometer range. The experimental results including multimodal size distributions are presented and discussed.  相似文献   

17.
Zahoransky RA  Dummin H  Laile E  Schauer T 《Talanta》1997,44(12):2225-2230
The flow field-flow fractionation (FIFFF) technique is a promising method for separating and analysing particles and large size macromolecules from a few nanometers to approximately 50 μm. A new fractionation channel is described featuring well defined flow conditions even for low channel heights with convenient assembling and operations features. The application of the new flow field-flow fractionation channel is proved by the analysis of pigments and other small particles of technical interest in the submicrometer range. The experimental results including multimodal size distributions are presented and discussed.  相似文献   

18.
    
The ability to isolate and purify white blood cells (WBCs) from mixed ensembles such as blood would benefit autologous cell-based therapeutics as well as diagnosis of WBC disorders. Current WBCs isolation methods have the limitations of low purity or requiring complex and expensive equipment. In addition, due to the overlap in size distribution between lymphocytes (i.e., a sub-population of WBCs) and red blood cells (RBCs), it is challenging to achieve isolation of entire WBCs populations. In this work, we developed an inertial microfluidics-based cell sorter, which enables size-based, high-throughput isolation, and enrichment of WBCs from RBC-lysed whole blood. Using the developed inertial microfluidic chip, the sorting resolution is sharpened within 2 μm, which achieved separation between 3 and 5 μm diameter particles. Thus, with the present cell sorter, a full population of WBCs can be isolated from RBC-lysed blood samples with recovery ratio of 92%, and merely 5% difference in the composition percentage of the three subpopulations of granulocytes, monocytes, and lymphocytes compared to the original sample. Furthermore, our cell sorter is designed to enable broad application of size-based inertial cell sorting by supplying a series of microchips with different sorting cutoff size. This strategy allows us to further enrich the lymphocytes population by twofold using another microchip with a cutoff size between 10 and 15 μm. With simplicity and efficiency, our cell sorter provides a powerful platform for isolating and sorting of WBCs and also envisions broad potential sorting applications for other cell types.  相似文献   

19.
    
Microfluidic particle focusing has been a vital prerequisite step in sample preparation for downstream particle separation, counting, detection, or analysis, and has attracted broad applications in biomedical and chemical areas. Besides all the active and passive focusing methods in Newtonian fluids, particle focusing in viscoelastic fluids has been attracting increasing interest because of its advantages induced by intrinsic fluid property. However, to achieve a well-defined focusing position, there is a need to extend channel lengths when focusing micrometer-sized or sub-microsized particles, which would result in the size increase of the microfluidic devices. This work investigated the sheathless viscoelastic focusing of particles and cells in a zigzag microfluidic channel. Benefit from the zigzag structure of the channel, the channel length and the footprint of the device can be reduced without sacrificing the focusing performance. In this work, the viscoelastic focusing, including the focusing of 10 μm polystyrene particles, 5 μm polystyrene particles, 5 μm magnetic particles, white blood cells (WBCs), red blood cells (RBCs), and cancer cells, were all demonstrated. Moreover, magnetophoretic separation of magnetic and nonmagnetic particles after viscoelastic pre-focusing was shown. This focusing technique has the potential to be used in a range of biomedical applications.  相似文献   

20.
In this work, we first introduce the fabrication of microfluidic cloth-based analytical devices (μCADs) using a wax screen-printing approach that is suitable for simple, inexpensive, rapid, low-energy-consumption and high-throughput preparation of cloth-based analytical devices. We have carried out a detailed study on the wax screen-printing of μCADs and have obtained some interesting results. Firstly, an analytical model is established for the spreading of molten wax in cloth. Secondly, a new wax screen-printing process has been proposed for fabricating μCADs, where the melting of wax into the cloth is much faster (∼5 s) and the heating temperature is much lower (75 °C). Thirdly, the experimental results show that the patterning effects of the proposed wax screen-printing method depend to a certain extent on types of screens, wax melting temperatures and melting time. Under optimized conditions, the minimum printing width of hydrophobic wax barrier and hydrophilic channel is 100 μm and 1.9 mm, respectively. Importantly, the developed analytical model is also well validated by these experiments. Fourthly, the μCADs fabricated by the presented wax screen-printing method are used to perform a proof-of-concept assay of glucose or protein in artificial urine with rapid high-throughput detection taking place on a 48-chamber cloth-based device and being performed by a visual readout. Overall, the developed cloth-based wax screen-printing and arrayed μCADs should provide a new research direction in the development of advanced sensor arrays for detection of a series of analytes relevant to many diverse applications.  相似文献   

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