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Chen YS, Huang CH, Pai PC, Seo J, Lei KF. A Review on Microfluidics-Based Impedance Biosensors. BIOSENSORS 2023; 13:bios13010083. [PMID: 36671918 PMCID: PMC9855525 DOI: 10.3390/bios13010083] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/21/2022] [Revised: 12/20/2022] [Accepted: 12/28/2022] [Indexed: 05/30/2023]
Abstract
Electrical impedance biosensors are powerful and continuously being developed for various biological sensing applications. In this line, the sensitivity of impedance biosensors embedded with microfluidic technologies, such as sheath flow focusing, dielectrophoretic focusing, and interdigitated electrode arrays, can still be greatly improved. In particular, reagent consumption reduction and analysis time-shortening features can highly increase the analytical capabilities of such biosensors. Moreover, the reliability and efficiency of analyses are benefited by microfluidics-enabled automation. Through the use of mature microfluidic technology, complicated biological processes can be shrunk and integrated into a single microfluidic system (e.g., lab-on-a-chip or micro-total analysis systems). By incorporating electrical impedance biosensors, hand-held and bench-top microfluidic systems can be easily developed and operated by personnel without professional training. Furthermore, the impedance spectrum provides broad information regarding cell size, membrane capacitance, cytoplasmic conductivity, and cytoplasmic permittivity without the need for fluorescent labeling, magnetic modifications, or other cellular treatments. In this review article, a comprehensive summary of microfluidics-based impedance biosensors is presented. The structure of this article is based on the different substrate material categorizations. Moreover, the development trend of microfluidics-based impedance biosensors is discussed, along with difficulties and challenges that may be encountered in the future.
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Affiliation(s)
- Yu-Shih Chen
- Department of Biomedical Engineering, Chang Gung University, Taoyuan 33302, Taiwan
| | - Chun-Hao Huang
- Department of Biomedical Engineering, Chang Gung University, Taoyuan 33302, Taiwan
| | - Ping-Ching Pai
- Department of Radiation Oncology, Linkou Chang Gung Memorial Hospital, Taoyuan 33305, Taiwan
| | - Jungmok Seo
- Department of Biomedical Engineering, Chang Gung University, Taoyuan 33302, Taiwan
- Department of Electrical & Electronic Engineering, Yonsei University, Seoul 120-749, Republic of Korea
| | - Kin Fong Lei
- Department of Biomedical Engineering, Chang Gung University, Taoyuan 33302, Taiwan
- Department of Radiation Oncology, Linkou Chang Gung Memorial Hospital, Taoyuan 33305, Taiwan
- Department of Electrical & Electronic Engineering, Yonsei University, Seoul 120-749, Republic of Korea
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2
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Migration and Alignment of Three Interacting Particles in Poiseuille Flow of Giesekus Fluids. FLUIDS 2021. [DOI: 10.3390/fluids6060218] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Effect of rheological property on the migration and alignment of three interacting particles in Poiseuille flow of Giesekus fluids is studied with the direct-forcing fictitious domain method for the Weissenberg number (Wi) ranging from 0.1 to 1.5, the mobility parameter ranging from 0.1 to 0.7, the ratio of particle diameter to channel height ranging from 0.2 to 0.4, the ratio of the solvent viscosity to the total viscosity being 0.3 and the initial distance (y0) of particles from the centerline ranging from 0 to 0.2. The results showed that the effect of y0 on the migration and alignment of particles is significant. The variation of off-centerline (y0 ≠ 0) particle spacing is completely different from that of on-centerline (y0 = 0) particle spacing. As the initial vertical distance y0 increased, the various types of particle spacing are more diversified. For the off-centerline particle, the change of particle spacing is mainly concentrated in the process of cross-flow migration. Additionally, the polymer extension is proportional to both the Weissenberg number and confinement ratio. The bigger the Wi and confinement ratio is, the bigger the increment of spacing is. The memory of shear-thinning is responsible for the reduction of d1. Furthermore, the particles migrate abnormally due to the interparticle interaction.
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3
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Cao Y, Floehr J, Ingebrandt S, Schnakenberg U. Dry Film Resist Laminated Microfluidic System for Electrical Impedance Measurements. MICROMACHINES 2021; 12:632. [PMID: 34072385 PMCID: PMC8228546 DOI: 10.3390/mi12060632] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/29/2021] [Revised: 05/19/2021] [Accepted: 05/25/2021] [Indexed: 12/03/2022]
Abstract
In micro-electrical-mechanical systems (MEMS), thick structures with high aspect ratios are often required. Dry film photoresist (DFR) in various thicknesses can be easily laminated and patterned using standard UV lithography. Here, we present a three-level DFR lamination process of SUEX for a microfluidic chip with embedded, vertically arranged microelectrodes for electrical impedance measurements. To trap and fix the object under test to the electrodes, an aperture is formed in the center of the ring-shaped electrodes in combination with a microfluidic suction channel underneath. In a proof-of-concept, the setup is characterized by electrical impedance measurements with polystyrene and ZrO2 spheres. The electrical impedance is most sensitive at approximately 2 kHz, and its magnitudes reveal around 200% higher values when a sphere is trapped. The magnitude values depend on the sizes of the spheres. Electrical equivalent circuits are applied to simulate the experimental results with a close match.
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Affiliation(s)
- Yuan Cao
- Institute of Materials in Electrical Engineering 1, RWTH Aachen University, Sommerfeldstraße 24, 52074 Aachen, Germany; (Y.C.); (S.I.)
| | - Julia Floehr
- Helmholtz-Institute for Biomedical Engineering, RWTH Aachen University Hospital, Pauwelsstraße 30, 52074 Aachen, Germany;
| | - Sven Ingebrandt
- Institute of Materials in Electrical Engineering 1, RWTH Aachen University, Sommerfeldstraße 24, 52074 Aachen, Germany; (Y.C.); (S.I.)
| | - Uwe Schnakenberg
- Institute of Materials in Electrical Engineering 1, RWTH Aachen University, Sommerfeldstraße 24, 52074 Aachen, Germany; (Y.C.); (S.I.)
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4
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Han Y, Zhao J, Jiao Z, Chao Z, Tárnok A, You Z. Diffractive Beam Shaper for Multiwavelength Lasers for Flow Cytometry. Cytometry A 2020; 99:194-204. [PMID: 33078537 DOI: 10.1002/cyto.a.24240] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2019] [Revised: 09/11/2020] [Accepted: 10/12/2020] [Indexed: 12/22/2022]
Abstract
Illumination spot in a flow cytometer is a crucial factor determining the measurement accuracy and stability. The traditional mechanism is to precisely calibrate multiple optical components to convert circular Gaussian beams into elliptical Gaussian beams, making it difficult to shape multiwavelength lasers simultaneously. A diffractive beam shaper for multicolor lasers with high simplicity, only containing one diffractive optical element and one focusing lens is created in this work. It can produce rectangular spots, of which the number, the sizes, and the positions are accurately determined by the incident wavelengths. Demonstrated in the customized microflow cytometer, the coefficient of variations (CV) of the optical signals by the beam shaper are 3.6-6.5%, comparable to those derived from the commercial instrument with 3.3-6.3% CVs. Benefiting from the narrow rectangular spots and the flexibility of diffractively shaped lasers, the measurement of bead sizes with 4-15 μm diameters and the real-time detection of flow velocity from 0.79 to 9.50 m/s with the CV of <5% are achieved. © 2020 International Society for Advancement of Cytometry.
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Affiliation(s)
- Yong Han
- State Key Laboratory of Precision Measurement Technology and Instrument, Tsinghua University, Beijing, China.,Department of Precision Instrument, Tsinghua University, Beijing, China.,Beijing Laboratory for Biomedical Detection Technology and Instrument, Tsinghua University, Beijing, China
| | - Jingjing Zhao
- Department of Structural Biology, Stanford University, School of Medicine, Stanford, California, USA
| | - Zeheng Jiao
- State Key Laboratory of Precision Measurement Technology and Instrument, Tsinghua University, Beijing, China.,Department of Precision Instrument, Tsinghua University, Beijing, China.,Beijing Laboratory for Biomedical Detection Technology and Instrument, Tsinghua University, Beijing, China
| | - Zixi Chao
- State Key Laboratory of Precision Measurement Technology and Instrument, Tsinghua University, Beijing, China.,Department of Precision Instrument, Tsinghua University, Beijing, China.,Beijing Laboratory for Biomedical Detection Technology and Instrument, Tsinghua University, Beijing, China
| | - Attila Tárnok
- Department of Precision Instrument, Tsinghua University, Beijing, China.,Institute for Medical Informatics, Statistics and Epidemiology (IMISE), University of Leipzig, Leipzig, Germany.,Department of Therapy Validation, Fraunhofer Institute for Cell Therapy and Immunology IZI, Leipzig, Germany
| | - Zheng You
- State Key Laboratory of Precision Measurement Technology and Instrument, Tsinghua University, Beijing, China.,Department of Precision Instrument, Tsinghua University, Beijing, China.,Beijing Laboratory for Biomedical Detection Technology and Instrument, Tsinghua University, Beijing, China
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5
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Ooi C, Earhart CM, Hughes CE, Lee JR, Wong DJ, Wilson RJ, Rohatgi R, Wang SX. Flow Homogenization Enables a Massively Parallel Fluidic Design for High-throughput and Multiplexed Cell Isolation. ADVANCED MATERIALS TECHNOLOGIES 2020; 5:1900960. [PMID: 33072854 PMCID: PMC7567302 DOI: 10.1002/admt.201900960] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/24/2019] [Accepted: 03/04/2020] [Indexed: 06/11/2023]
Abstract
Microfluidic devices are widely used for applications such as cell isolation. Currently, the most common method to improve throughput for microfluidic devices involves fabrication of multiple, identical channels in parallel. However, this 'numbering up' only occurs in one dimension, thereby limiting gains in volumetric throughput. In contrast, macro-fluidic devices permit high volumetric flow-rates but lack the finer control of microfluidics. Here, we demonstrate how a micro-pore array design enables flow homogenization across a magnetic cell capture device, thus creating a massively parallel series of micro-scale flow channels with consistent fluidic and magnetic properties, regardless of spatial location. This design enables scaling in 2-dimensions, allowing flow-rates exceeding 100 mL/hr while maintaining >90% capture efficiencies of spiked lung cancer cells from blood in a simulated circulating tumor cell system. Additionally, this design facilitates modularity in operation, which we demonstrate by combining two different devices in tandem for multiplexed cell separation in a single pass with no additional cell losses from processing.
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Affiliation(s)
| | - Christopher M. Earhart
- Department of Materials Science and Engineering, Stanford University, Stanford, California, USA
| | - Casey E. Hughes
- Division of Oncology, Department of Medicine, Stanford University School of Medicine, Stanford, California, USA; Department of Biochemistry, University of Utah School of Medicine, Salt Lake City, Utah, USA
| | - Jung-Rok Lee
- Division of Mechanical and Biomechanical Engineering, Ewha Womans University, Seoul, South Korea
| | - Dawson J. Wong
- Department of Electrical Engineering, Stanford University, Stanford, California, USA
| | - Robert J. Wilson
- Department of Materials Science and Engineering, Stanford University, Stanford, California, USA
| | - Rajat Rohatgi
- Department of Biochemistry, Stanford University School of Medicine, Stanford, California, USA
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6
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Dabighi A, Toghraie D. A new microfluidic device for separating circulating tumor cells based on their physical properties by using electrophoresis and dielectrophoresis forces within an electrical field. COMPUTER METHODS AND PROGRAMS IN BIOMEDICINE 2020; 185:105147. [PMID: 31669960 DOI: 10.1016/j.cmpb.2019.105147] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/01/2019] [Revised: 10/13/2019] [Accepted: 10/20/2019] [Indexed: 06/10/2023]
Abstract
BACKGROUND AND OBJECTIVE The presence of circulating tumor cells in the patient's blood is a clinical factor that indicates the initiation of metastasis. METHODS In this paper, a microfluidic device is designed to separate, enumerate, and to diagnose cancer cells from the patient's blood sample. Here, we present a new microfluidic device that is capable of separating circulating tumor cells based on their physical properties by using electrophoresis and dielectrophoresis forces within an electrical field. Cells are modeled as spherical particles, each size as a representor of different cells. RESULTS The distance between cells has been increased, and by using a novel method of rolling up the convergent and divergent channels, the primary distance of elements, which was 50 µm, reached 142-178.5. Cells with different diameters sense a different force, and therefore, cancer cells can be separating from other cells in the blood, such as white blood cells. To make the current device, practical for clinical studies, a cell enumerator is designed for downstream of cell separator. In the cell enumerator, a change in impedance occurs when a cell passes through the sensor. CONCLUSIONS By measuring the electrical current between two electrodes of the cell enumerator sensor, the exact count of cells can be obtained.
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Affiliation(s)
- Ali Dabighi
- Department of Mechanical Engineering, Islamic Azad University, Khomeinishahr Branch, Khomeinishahr 84175-119, Iran
| | - Davood Toghraie
- Department of Mechanical Engineering, Islamic Azad University, Khomeinishahr Branch, Khomeinishahr 84175-119, Iran.
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7
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Gong Y, Fan N, Yang X, Peng B, Jiang H. New advances in microfluidic flow cytometry. Electrophoresis 2018; 40:1212-1229. [PMID: 30242856 DOI: 10.1002/elps.201800298] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2018] [Revised: 09/07/2018] [Accepted: 09/15/2018] [Indexed: 01/22/2023]
Abstract
In recent years, researchers are paying the increasing attention to the development of portable microfluidic diagnostic devices including microfluidic flow cytometry for the point-of-care testing. Microfluidic flow cytometry, where microfluidics and flow cytometry work together to realize novel functionalities on the microchip, provides a powerful tool for measuring the multiple characteristics of biological samples. The development of a portable, low-cost, and compact flow cytometer can benefit the health care in underserved areas such as Africa or Asia. In this article, we review recent advancements of microfluidics including sample pumping, focusing and sorting, novel detection approaches, and data analysis in the field of flow cytometry. The challenge of microfluidic flow cytometry is also examined briefly.
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Affiliation(s)
- Yanli Gong
- School of Mechanical and Electrical Engineering, University of Electronic Science and Technology of China, Chengdu, P. R. China
| | - Na Fan
- School of Mechanical and Electrical Engineering, University of Electronic Science and Technology of China, Chengdu, P. R. China
| | - Xu Yang
- School of Mechanical and Electrical Engineering, University of Electronic Science and Technology of China, Chengdu, P. R. China
| | - Bei Peng
- School of Mechanical and Electrical Engineering, University of Electronic Science and Technology of China, Chengdu, P. R. China
| | - Hai Jiang
- School of Mechanical and Electrical Engineering, University of Electronic Science and Technology of China, Chengdu, P. R. China
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8
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Balaji V, Castro K, Folch A. A Laser-Engraving Technique for Portable Micropneumatic Oscillators. MICROMACHINES 2018; 9:E426. [PMID: 30424359 PMCID: PMC6187360 DOI: 10.3390/mi9090426] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/13/2018] [Revised: 08/13/2018] [Accepted: 08/22/2018] [Indexed: 01/19/2023]
Abstract
Microfluidic automation technology is at a stage where the complexity and cost of external hardware control often impose severe limitations on the size and functionality of microfluidic systems. Developments in autonomous microfluidics are intended to eliminate off-chip controls to enable scalable systems. Timing is a fundamental component of the digital logic required to manipulate fluidic flow. The authors present a self-driven pneumatic ring oscillator manufactured by assembling an elastomeric sheet of polydimethylsiloxane (PDMS) between two laser-engraved polymethylmethacrylate (PMMA) layers via surface activation through treatment with 3-aminopropyltriethoxysilane (APTES). The frequency of the fabricated oscillators is in the range of 3⁻7.5 Hz with a maximum of 14 min constant frequency syringe-powered operation. The control of a fluidic channel with the oscillator stages is demonstrated. The fabrication process represents an improvement in manufacturability compared to previous molding or etching approaches, and the resulting devices are inexpensive and portable, making the technology potentially applicable for wider use.
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Affiliation(s)
- Vidhya Balaji
- Department of Electrical Engineering, University of Washington, Seattle, WA 98195, USA.
| | - Kurt Castro
- Department of Bioengineering, University of Washington, Seattle, WA 98195, USA.
| | - Albert Folch
- Department of Bioengineering, University of Washington, Seattle, WA 98195, USA.
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9
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Rickel JMR, Dixon AJ, Klibanov AL, Hossack JA. A flow focusing microfluidic device with an integrated Coulter particle counter for production, counting and size characterization of monodisperse microbubbles. LAB ON A CHIP 2018; 18:2653-2664. [PMID: 30070301 PMCID: PMC6566100 DOI: 10.1039/c8lc00496j] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
Flow focusing microfluidic devices (FFMDs) have been investigated for the production of monodisperse populations of microbubbles for chemical, biomedical and mechanical engineering applications. High-speed optical microscopy is commonly used to monitor FFMD microbubble production parameters, such as diameter and production rate, but this limits the scalability and portability of the approach. In this work, a novel FFMD design featuring integrated electronics for measuring microbubble diameters and production rates is presented. A micro Coulter particle counter (μCPC), using electrodes integrated within the expanding nozzle of an FFMD (FFMD-μCPC), was designed, fabricated and tested. Finite element analysis (FEA) of optimal electrode geometry was performed and validated with experimental data. Electrical data was collected for 8-20 μm diameter microbubbles at production rates up to 3.25 × 105 MB s-1 and compared to both high-speed microscopy data and FEA simulations. Within a valid operating regime, Coulter counts of microbubble production rates matched optical reference values. The Coulter method agreed with the optical reference method in evaluating the microbubble diameter to a coefficient of determination of R2 = 0.91.
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Affiliation(s)
- J M Robert Rickel
- Department of Biomedical Engineering, University of Virginia, Charlottesville, Virginia, USA.
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10
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Szydzik C, Brazilek RJ, Khoshmanesh K, Akbaridoust F, Knoerzer M, Thurgood P, Muir I, Marusic I, Nandurkar H, Mitchell A, Nesbitt WS. Elastomeric microvalve geometry affects haemocompatibility. LAB ON A CHIP 2018; 18:1778-1792. [PMID: 29789838 DOI: 10.1039/c7lc01320e] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
This paper reports on the parameters that determine the haemocompatibility of elastomeric microvalves for blood handling in microfluidic systems. Using a comprehensive investigation of blood function, we describe a hierarchy of haemocompatibility as a function of microvalve geometry and identify a "normally-closed" v-gate pneumatic microvalve design that minimally affects blood plasma fibrinogen and von Willebrand factor composition, minimises effects on erythrocyte structure and function, and limits effects on platelet activation and aggregation, while facilitating rapid switching control for blood sample delivery. We propose that the haemodynamic profile of valve gate geometries is a significant determinant of platelet-dependent biofouling and haemocompatibility. Overall our findings suggest that modification of microvalve gate geometry and consequently haemodynamic profile can improve haemocompatibility, while minimising the requirement for chemical or protein modification of microfluidic surfaces. This biological insight and approach may be harnessed to inform future haemocompatible microfluidic valve and component design, and is an advance towards lab-on-chip automation for blood based diagnostic systems.
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Affiliation(s)
- Crispin Szydzik
- School of Engineering, RMIT University, 124 La Trobe Street, Melbourne, Victoria 3000, Australia.
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11
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Shrirao AB, Fritz Z, Novik EM, Yarmush GM, Schloss RS, Zahn JD, Yarmush ML. Microfluidic flow cytometry: The role of microfabrication methodologies, performance and functional specification. TECHNOLOGY 2018; 6:1-23. [PMID: 29682599 PMCID: PMC5907470 DOI: 10.1142/s2339547818300019] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Flow cytometry is an invaluable tool utilized in modern biomedical research and clinical applications requiring high throughput, high resolution particle analysis for cytometric characterization and/or sorting of cells and particles as well as for analyzing results from immunocytometric assays. In recent years, research has focused on developing microfluidic flow cytometers with the motivation of creating smaller, less expensive, simpler, and more autonomous alternatives to conventional flow cytometers. These devices could ideally be highly portable, easy to operate without extensive user training, and utilized for research purposes and/or point-of-care diagnostics especially in limited resource facilities or locations requiring on-site analyses. However, designing a device that fulfills the criteria of high throughput analysis, automation and portability, while not sacrificing performance is not a trivial matter. This review intends to present the current state of the field and provide considerations for further improvement by focusing on the key design components of microfluidic flow cytometers. The recent innovations in particle focusing and detection strategies are detailed and compared. This review outlines performance matrix parameters of flow cytometers that are interdependent with each other, suggesting trade offs in selection based on the requirements of the applications. The ongoing contribution of microfluidics demonstrates that it is a viable technology to advance the current state of flow cytometry and develop automated, easy to operate and cost-effective flow cytometers.
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Affiliation(s)
- Anil B Shrirao
- Department of Biomedical Engineering, Rutgers University, 599, Taylor Road, Piscataway, NJ 08854
| | - Zachary Fritz
- Department of Biomedical Engineering, Rutgers University, 599, Taylor Road, Piscataway, NJ 08854
| | - Eric M Novik
- Hurel Corporation, 671, Suite B, U.S. Highway 1, North Brunswick, NJ 08902
| | - Gabriel M Yarmush
- Department of Biomedical Engineering, Rutgers University, 599, Taylor Road, Piscataway, NJ 08854
| | - Rene S Schloss
- Department of Biomedical Engineering, Rutgers University, 599, Taylor Road, Piscataway, NJ 08854
| | - Jeffrey D Zahn
- Department of Biomedical Engineering, Rutgers University, 599, Taylor Road, Piscataway, NJ 08854
| | - Martin L Yarmush
- Department of Biomedical Engineering, Rutgers University, 599, Taylor Road, Piscataway, NJ 08854
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12
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Gordeev AA, Chetverin AB. Methods for Screening Live Cells. BIOCHEMISTRY (MOSCOW) 2018; 83:S81-S102. [DOI: 10.1134/s0006297918140080] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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13
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Asghari M, Serhatlioglu M, Ortaç B, Solmaz ME, Elbuken C. Sheathless Microflow Cytometry Using Viscoelastic Fluids. Sci Rep 2017; 7:12342. [PMID: 28955054 PMCID: PMC5617843 DOI: 10.1038/s41598-017-12558-2] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2017] [Accepted: 09/06/2017] [Indexed: 11/17/2022] Open
Abstract
Microflow cytometry is a powerful technique for characterization of particles suspended in a solution. In this work, we present a microflow cytometer based on viscoelastic focusing. 3D single-line focusing of microparticles was achieved in a straight capillary using viscoelastic focusing which alleviated the need for sheath flow or any other actuation mechanism. Optical detection was performed by fiber coupled light source and photodetectors. Using this system, we present the detection of microparticles suspended in three different viscoelastic solutions. The rheological properties of the solutions were measured and used to assess the focusing performance both analytically and numerically. The results were verified experimentally, and it has been shown that polyethlyene oxide (PEO) and hyaluronic acid (HA) based sheathless microflow cytometer demonstrates similar performance to state-of-the art flow cytometers. The sheathless microflow cytometer was shown to present 780 particles/s throughput and 5.8% CV for the forward scatter signal for HA-based focusing. The presented system is composed of a single capillary to accommodate the fluid and optical fibers to couple the light to the fluid of interest. Thanks to its simplicity, the system has the potential to widen the applicability of microflow cytometers.
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Affiliation(s)
- Mohammad Asghari
- UNAM - National Nanotechnology Research Center, Institute of Materials Science and Nanotechnology, Bilkent University, 06800, Ankara, Turkey
| | - Murat Serhatlioglu
- UNAM - National Nanotechnology Research Center, Institute of Materials Science and Nanotechnology, Bilkent University, 06800, Ankara, Turkey
| | - Bülend Ortaç
- UNAM - National Nanotechnology Research Center, Institute of Materials Science and Nanotechnology, Bilkent University, 06800, Ankara, Turkey
| | - Mehmet E Solmaz
- Department of Electrical and Electronics Engineering, Izmir Katip Celebi University, 35620, Izmir, Turkey
| | - Caglar Elbuken
- UNAM - National Nanotechnology Research Center, Institute of Materials Science and Nanotechnology, Bilkent University, 06800, Ankara, Turkey.
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14
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Gencturk E, Mutlu S, Ulgen KO. Advances in microfluidic devices made from thermoplastics used in cell biology and analyses. BIOMICROFLUIDICS 2017; 11:051502. [PMID: 29152025 PMCID: PMC5654984 DOI: 10.1063/1.4998604] [Citation(s) in RCA: 55] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2017] [Accepted: 10/11/2017] [Indexed: 05/10/2023]
Abstract
Silicon and glass were the main fabrication materials of microfluidic devices, however, plastics are on the rise in the past few years. Thermoplastic materials have recently been used to fabricate microfluidic platforms to perform experiments on cellular studies or environmental monitoring, with low cost disposable devices. This review describes the present state of the development and applications of microfluidic systems used in cell biology and analyses since the year 2000. Cultivation, separation/isolation, detection and analysis, and reaction studies are extensively discussed, considering only microorganisms (bacteria, yeast, fungi, zebra fish, etc.) and mammalian cell related studies in the microfluidic platforms. The advantages/disadvantages, fabrication methods, dimensions, and the purpose of creating the desired system are explained in detail. An important conclusion of this review is that these microfluidic platforms are still open for research and development, and solutions need to be found for each case separately.
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Affiliation(s)
- Elif Gencturk
- Department of Chemical Engineering, Biosystems Engineering Laboratory, Bogazici University, 34342 Istanbul, Turkey
| | - Senol Mutlu
- Department of Electrical and Electronics Engineering, BUMEMS Laboratory, Bogazici University, 34342 Istanbul, Turkey
| | - Kutlu O Ulgen
- Department of Chemical Engineering, Biosystems Engineering Laboratory, Bogazici University, 34342 Istanbul, Turkey
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15
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Ossowski P, Wojtkowski M, Munro PRT. Classification of biological micro-objects using optical coherence tomography: in silico study. BIOMEDICAL OPTICS EXPRESS 2017; 8:3606-3626. [PMID: 28856039 PMCID: PMC5560829 DOI: 10.1364/boe.8.003606] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/07/2017] [Revised: 05/05/2017] [Accepted: 05/19/2017] [Indexed: 05/24/2023]
Abstract
We report on the development of a technique for differentiating between biological micro-objects using a rigorous, full-wave model of OCT image formation. We model an existing experimental prototype which uses OCT to interrogate a microfluidic chip containing the blood cells. A full-wave model is required since the technique uses light back-scattered by a scattering substrate, rather than by the cells directly. The light back-scattered by the substrate is perturbed upon propagation through the cells, which flow between the substrate and imaging system's objective lens. We present the key elements of the 3D, Maxwell equation-based computational model, the key findings of the computational study and a comparison with experimental results.
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Affiliation(s)
- Paweł Ossowski
- Institute of Physics, Faculty of Physics, Astronomy and Informatics, Nicolaus Copernicus University Grudziadzka 5, 87-100 Torun, Poland
- These authors contributed equally to this work
| | - Maciej Wojtkowski
- Institute of Physics, Faculty of Physics, Astronomy and Informatics, Nicolaus Copernicus University Grudziadzka 5, 87-100 Torun, Poland
- Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw, Poland
| | - Peter RT Munro
- Department of Medical Physics and Biomedical Engineering, University College London, Malet Place, Gower Street, London WC1E 6BT, UK
- School of Electrical, Electronic & Computer Engineering, The University of Western Australia, 35 Stirling Highway, Crawley, Western Australia 6009, Australia
- These authors contributed equally to this work
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16
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Etcheverry S, Faridi A, Ramachandraiah H, Kumar T, Margulis W, Laurell F, Russom A. High performance micro-flow cytometer based on optical fibres. Sci Rep 2017; 7:5628. [PMID: 28717236 PMCID: PMC5514097 DOI: 10.1038/s41598-017-05843-7] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2017] [Accepted: 06/05/2017] [Indexed: 12/05/2022] Open
Abstract
Flow cytometry is currently the gold standard for analysis of cells in the medical laboratory and biomedical research. Fuelled by the need of point-of-care diagnosis, a significant effort has been made to miniaturize and reduce cost of flow cytometers. However, despite recent advances, current microsystems remain less versatile and much slower than their large-scale counterparts. In this work, an all-silica fibre microflow cytometer is presented that measures fluorescence and scattering from particles and cells. It integrates cell transport in circular capillaries and light delivery by optical fibres. Single-stream cell focusing is performed by Elasto-inertial microfluidics to guarantee accurate and sensitive detection. The capability of this technique is extended to high flow rates (up to 800 µl/min), enabling a throughput of 2500 particles/s. The robust, portable and low-cost system described here could be the basis for a point-of-care flow cytometer with a performance comparable to commercial systems.
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Affiliation(s)
- S Etcheverry
- Department of Applied Physics, KTH Royal Institute of Technology, Stockholm, Sweden.
- Department of Fibre Optics, RISE Acreo AB, Stockholm, Sweden.
| | - A Faridi
- Division of Proteomics and Nanobiotechnology, Science for Life Laboratory, KTH Royal Institute of Technology, Solna, Sweden
| | - H Ramachandraiah
- Division of Proteomics and Nanobiotechnology, Science for Life Laboratory, KTH Royal Institute of Technology, Solna, Sweden
| | - T Kumar
- Division of Proteomics and Nanobiotechnology, Science for Life Laboratory, KTH Royal Institute of Technology, Solna, Sweden
| | - W Margulis
- Department of Applied Physics, KTH Royal Institute of Technology, Stockholm, Sweden
- Department of Fibre Optics, RISE Acreo AB, Stockholm, Sweden
| | - F Laurell
- Department of Applied Physics, KTH Royal Institute of Technology, Stockholm, Sweden
| | - A Russom
- Division of Proteomics and Nanobiotechnology, Science for Life Laboratory, KTH Royal Institute of Technology, Solna, Sweden
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17
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Lim AE, Lim CY, Lam YC, Taboryski R, Wang SR. Effect of nanostructures orientation on electroosmotic flow in a microfluidic channel. NANOTECHNOLOGY 2017; 28:255303. [PMID: 28510536 DOI: 10.1088/1361-6528/aa734f] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Electroosmotic flow (EOF) is an electric-field-induced fluid flow that has numerous micro-/nanofluidic applications, ranging from pumping to chemical and biomedical analyses. Nanoscale networks/structures are often integrated in microchannels for a broad range of applications, such as electrophoretic separation of biomolecules, high reaction efficiency catalytic microreactors, and enhancement of heat transfer and sensing. Their introduction has been known to reduce EOF. Hitherto, a proper study on the effect of nanostructures orientation on EOF in a microfluidic channel is yet to be carried out. In this investigation, we present a novel fabrication method for nanostructure designs that possess maximum orientation difference, i.e. parallel versus perpendicular indented nanolines, to examine the effect of nanostructures orientation on EOF. It consists of four phases: fabrication of silicon master, creation of mold insert via electroplating, injection molding with cyclic olefin copolymer, and thermal bonding and integration of practical inlet/outlet ports. The effect of nanostructures orientation on EOF was studied experimentally by current monitoring method. The experimental results show that nanolines which are perpendicular to the microchannel reduce the EOF velocity significantly (approximately 20%). This flow velocity reduction is due to the distortion of local electric field by the perpendicular nanolines at the nanostructured surface as demonstrated by finite element simulation. In contrast, nanolines which are parallel to the microchannel have no effect on EOF, as it can be deduced that the parallel nanolines do not distort the local electric field. The outcomes of this investigation contribute to the precise control of EOF in lab-on-chip devices, and fundamental understanding of EOF in devices which utilize nanostructured surfaces for chemical and biological analyses.
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Affiliation(s)
- An Eng Lim
- School of Mechanical and Aerospace engineering, Nanyang Technological University, 50 Nanyang Avenue 639798, Singapore
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18
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Vander Wiel JB, Mikulicz JD, Boysen MR, Hashemi N, Kalgren P, Nauman L, Baetzold SJ, Powell GG, He Q, Hashemi NN. Characterization of Chlorella vulgaris and Chlorella protothecoides using multi-pixel photon counters in a 3D focusing optofluidic system. RSC Adv 2017. [DOI: 10.1039/c6ra25837a] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
A new type of multi-pixel photon counter was employed to miniaturize the device, lower its power consumption, and make it insensitive to magnetic fields.
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Affiliation(s)
| | | | | | - Niloofar Hashemi
- Department of Materials Science and Engineering
- Sharif University of Technology
- Tehran
- Iran
| | - Patrick Kalgren
- Department of Mechanical Engineering
- Iowa State University
- Ames
- USA
| | - Levi M. Nauman
- Department of Mechanical Engineering
- Iowa State University
- Ames
- USA
| | - Seth J. Baetzold
- Department of Mechanical Engineering
- Iowa State University
- Ames
- USA
| | | | - Qing He
- Department of Mechanical Engineering
- Iowa State University
- Ames
- USA
| | - Nicole Nastaran Hashemi
- Department of Mechanical Engineering
- Iowa State University
- Ames
- USA
- Center for Advanced Host Defense Immunobiotics and Translational Comparative Medicine
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19
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Novotný J, Foret F. Fluid manipulation on the micro-scale: Basics of fluid behavior in microfluidics. J Sep Sci 2016; 40:383-394. [DOI: 10.1002/jssc.201600905] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2016] [Revised: 09/22/2016] [Accepted: 09/23/2016] [Indexed: 02/04/2023]
Affiliation(s)
- Jakub Novotný
- Department of Bioanalytical Instrumentation; Institute of Analytical Chemistry of the Czech Academy of Sciences, v. v. i; Brno Czech Republic
- Department of Biological and Biochemical Sciences, Faculty of Chemical Technology; University of Pardubice; Pardubice Czech Republic
| | - František Foret
- Department of Bioanalytical Instrumentation; Institute of Analytical Chemistry of the Czech Academy of Sciences, v. v. i; Brno Czech Republic
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20
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Zhao Y, Li Q, Hu X, Lo Y. Microfluidic cytometers with integrated on-chip optical systems for red blood cell and platelet counting. BIOMICROFLUIDICS 2016; 10:064119. [PMID: 28058085 PMCID: PMC5188361 DOI: 10.1063/1.4972105] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/19/2016] [Accepted: 11/27/2016] [Indexed: 05/07/2023]
Abstract
A microfluidic cytometer with integrated on-chip optical systems was designed for red blood cell (RBC) and platelet (PLT) counting. The design, fabrication, and characterization of the microfluidic cytometer with on-chip optical signal detection were described. With process using only a single mask, the device that integrates optical fibers and on-chip microlens with microfluidic channels on a polydimethylsiloxane layer by standard soft photolithography. This compact structure increased the sensitivity of the device and eliminated time-consuming free-space optical alignments. The microfluidic cytometer was used to count red blood cells and platelets. Forward scatter and extinction were collected simultaneously for each cell. Experimental results indicated that the microfluidic cytometer exhibited comparable performance with a conventional cytometer and demonstrated superior capacity to detect on-chip optical signals in a highly compact, simple, truly portable, and low-cost format that is well suitable for point-of-care clinical diagnostics.
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Affiliation(s)
- Yingying Zhao
- School of Life Science, Key Laboratory of Convergence Medical Engineering System and Healthcare Technology, Beijing Institute of Technology , Beijing 100081, China
| | - Qin Li
- School of Life Science, Key Laboratory of Convergence Medical Engineering System and Healthcare Technology, Beijing Institute of Technology , Beijing 100081, China
| | - Xiaoming Hu
- School of Life Science, Key Laboratory of Convergence Medical Engineering System and Healthcare Technology, Beijing Institute of Technology , Beijing 100081, China
| | - Yuhwa Lo
- Department of Electrical and Computer Engineering, University of California San Diego , California 92093-0407, USA
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21
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Hybrid Microfluidic Platform for Multifactorial Analysis Based on Electrical Impedance, Refractometry, Optical Absorption and Fluorescence. MICROMACHINES 2016; 7:mi7100181. [PMID: 30404355 PMCID: PMC6190102 DOI: 10.3390/mi7100181] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/01/2016] [Revised: 09/12/2016] [Accepted: 09/26/2016] [Indexed: 11/18/2022]
Abstract
This paper describes the development of a novel microfluidic platform for multifactorial analysis integrating four label-free detection methods: electrical impedance, refractometry, optical absorption and fluorescence. We present the rationale for the design and the details of the microfabrication of this multifactorial hybrid microfluidic chip. The structure of the platform consists of a three-dimensionally patterned polydimethylsiloxane top part attached to a bottom SU-8 epoxy-based negative photoresist part, where microelectrodes and optical fibers are incorporated to enable impedance and optical analysis. As a proof of concept, the chip functions have been tested and explored, enabling a diversity of applications: (i) impedance-based identification of the size of micro beads, as well as counting and distinguishing of erythrocytes by their volume or membrane properties; (ii) simultaneous determination of the refractive index and optical absorption properties of solutions; and (iii) fluorescence-based bead counting.
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22
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Zhao J, You Z. A Microflow Cytometer with a Rectangular Quasi-Flat-Top Laser Spot. SENSORS 2016; 16:s16091474. [PMID: 27626428 PMCID: PMC5038752 DOI: 10.3390/s16091474] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/22/2016] [Accepted: 09/08/2016] [Indexed: 01/13/2023]
Abstract
This work develops a microflow cytometer, based on a microfluidic chip for three-dimensional (3D) hydrodynamic focusing and a binary optical element (BOE) for shaping and homogenizing a laser beam. The microfluidic chip utilizes sheath flows to confine the sample flow along the channel centerline with a narrow cross section. In addition to hydrodynamic focusing, secondary flows are generated to strengthen the focusing in the vertical direction. In experiments, the chip was able to focus the sample flow with cross sections of 15 μm high and 8-30 μm wide at 5 m/s, under the condition of the sample flow rates between 10 and 120 μL/min. Instead of using the conventional elliptical Gaussian spot for optical detection, we used a specially designed BOE and obtained a 50 μm × 10 μm rectangular quasi-flat-top spot. The microflow cytometer combining the chip and the BOE was tested to count 3, 5, and 7 μm fluorescence microbeads, and the experimental results were comparable to or better than those derived from two commercial instruments.
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Affiliation(s)
- Jingjing Zhao
- State Key Laboratory of Precision Measurement Technology and Instrument, Tsinghua University, Beijing 100084, China.
- Department of Precision Instrument, Tsinghua University, Beijing 100084, China.
- Beijing Laboratory for Biomedical Detection Technology and Instrument, Tsinghua University, Beijing 100084, China.
| | - Zheng You
- State Key Laboratory of Precision Measurement Technology and Instrument, Tsinghua University, Beijing 100084, China.
- Department of Precision Instrument, Tsinghua University, Beijing 100084, China.
- Beijing Laboratory for Biomedical Detection Technology and Instrument, Tsinghua University, Beijing 100084, China.
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23
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Zhao J, You Z. Using binary optical elements (BOEs) to generate rectangular spots for illumination in micro flow cytometer. BIOMICROFLUIDICS 2016; 10:054111. [PMID: 27733892 PMCID: PMC5045444 DOI: 10.1063/1.4963010] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/30/2016] [Accepted: 09/07/2016] [Indexed: 06/06/2023]
Abstract
This work introduces three rectangular quasi-flat-top spots, which are provided by binary optical elements (BOEs) and utilized for the illumination in a microflow cytometer. The three spots contain, respectively, one, two, and three rectangles (R1, R2, and R3). To test the performance of this mechanism, a microflow cytometer is established by integrating the BOEs and a three-dimensional hydrodynamic focusing chip. Through the experiments of detecting fluorescence microbeads, the three spots present good fluorescence coefficients of variation in comparison with those derived from commercial instruments. Benefiting from a high spatial resolution, when using R1 spot, the micro flow cytometer can perform a throughput as high as 20 000 events per second (eps). Illuminated by R2 or R3 spot, one bead emits fluorescence twice or thrice, thus the velocity can be measured in real time. Besides, the R3 spot provides a long-time exposure, which is conducive to improving fluorescence intensity and the measurement stability. In brief, using the spots shaped and homogenized by BOEs for illumination can increase the performance and the functionality of a micro flow cytometer.
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24
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Simon P, Frankowski M, Bock N, Neukammer J. Label-free whole blood cell differentiation based on multiple frequency AC impedance and light scattering analysis in a micro flow cytometer. LAB ON A CHIP 2016; 16:2326-38. [PMID: 27229300 DOI: 10.1039/c6lc00128a] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
We developed a microfluidic sensor for label-free flow cytometric cell differentiation by combined multiple AC electrical impedance and light scattering analysis. The measured signals are correlated to cell volume, membrane capacity and optical properties of single cells. For an improved signal to noise ratio, the microfluidic sensor incorporates two electrode pairs for differential impedance detection. One-dimensional sheath flow focusing was implemented, which allows single particle analysis at kHz count rates. Various monodisperse particles and differentiation of leukocytes in haemolysed samples served to benchmark the microdevice applying combined AC impedance and side scatter analyses. In what follows, we demonstrate that AC impedance measurements at selected frequencies allow label-free discrimination of platelets, erythrocytes, monocytes, granulocytes and lymphocytes in whole blood samples involving dilution only. Immunofluorescence staining was applied to validate the results of the label-free cell analysis. Reliable differentiation and enumeration of cells in whole blood by AC impedance detection have the potential to support medical diagnosis for patients with haemolysis resistant erythrocytes or abnormally sensitive leucocytes, i.e. for patients suffering from anaemia or leukaemia.
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Affiliation(s)
- Peter Simon
- Physikalisch-Technische Bundesanstalt (PTB), Abbestrasse 2-12, 10587 Berlin, Germany.
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25
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Ossowski P, Raiter-Smiljanic A, Szkulmowska A, Bukowska D, Wiese M, Derzsi L, Eljaszewicz A, Garstecki P, Wojtkowski M. Differentiation of morphotic elements in human blood using optical coherence tomography and a microfluidic setup. OPTICS EXPRESS 2015; 23:27724-38. [PMID: 26480435 DOI: 10.1364/oe.23.027724] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
We demonstrate a novel optical method for the detection and differentiation between erythrocytes and leukocytes that uses amplitude and phase information provided by optical coherence tomography (OCT). Biological cells can introduce significant phase modulation with substantial scattering anisotropy and dominant forward-scattered light. Such physical properties may favor the use of a trans-illumination imaging technique. However, an epi-illumination mode may be more practical and robust in many applications. This study describes a new way of measuring the phase modulation introduced by flowing microobjects. The novel part of this invention is that it uses the backscattered signal from the substrate located below the flowing/moving objects. The identification of cells is based on phase-sensitive OCT signals. To differentiate single cells, a custom-designed microfluidic device with a highly scattering substrate is introduced. The microchannels are molded in polydimethylsiloxane (PDMS) mixed with titanium dioxide (TiO2) to ensure high scattering properties. The statistical parameters of the measured signal depend on the cells' features, such as their size, shape, and internal structure.
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26
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Guckenberger DJ, de Groot TE, Wan AMD, Beebe DJ, Young EWK. Micromilling: a method for ultra-rapid prototyping of plastic microfluidic devices. LAB ON A CHIP 2015; 15:2364-78. [PMID: 25906246 PMCID: PMC4439323 DOI: 10.1039/c5lc00234f] [Citation(s) in RCA: 233] [Impact Index Per Article: 25.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
This tutorial review offers protocols, tips, insight, and considerations for practitioners interested in using micromilling to create microfluidic devices. The objective is to provide a potential user with information to guide them on whether micromilling would fill a specific need within their overall fabrication strategy. Comparisons are made between micromilling and other common fabrication methods for plastics in terms of technical capabilities and cost. The main discussion focuses on "how-to" aspects of micromilling, to enable a user to select proper equipment and tools, and obtain usable microfluidic parts with minimal start-up time and effort. The supplementary information provides more extensive discussion on CNC mill setup, alignment, and programming. We aim to reach an audience with minimal prior experience in milling, but with strong interests in fabrication of microfluidic devices.
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Affiliation(s)
- David J Guckenberger
- Department of Biomedical Engineering, Wisconsin Institutes for Medical Research, University of Wisconsin-Madison, Madison, WI, USA
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27
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Frankowski M, Simon P, Bock N, El-Hasni A, Schnakenberg U, Neukammer J. Simultaneous optical and impedance analysis of single cells: A comparison of two microfluidic sensors with sheath flow focusing. Eng Life Sci 2015. [DOI: 10.1002/elsc.201400078] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Affiliation(s)
| | - Peter Simon
- Physikalisch-Technische Bundesanstalt (PTB); Berlin Germany
| | - Nicole Bock
- Physikalisch-Technische Bundesanstalt (PTB); Berlin Germany
| | - Akram El-Hasni
- Institute of Materials in Electrical Engineering I; RWTH Aachen University; Aachen Germany
| | - Uwe Schnakenberg
- Institute of Materials in Electrical Engineering I; RWTH Aachen University; Aachen Germany
| | - Jörg Neukammer
- Physikalisch-Technische Bundesanstalt (PTB); Berlin Germany
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28
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Hebert CG, Staton SJR, Hudson TQ, Hart SJ, Lopez-Mariscal C, Terray A. Dynamic radial positioning of a hydrodynamically focused particle stream enabled by a three-dimensional microfluidic nozzle. BIOMICROFLUIDICS 2015; 9:024106. [PMID: 25825621 PMCID: PMC4376750 DOI: 10.1063/1.4914869] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2014] [Accepted: 03/03/2015] [Indexed: 06/04/2023]
Abstract
The ability to confine flows and focus particle streams has become an integral component of the design of microfluidic systems for the analysis of a wide range of samples. Presented here is the implementation of a 3D microfluidic nozzle capable of both focusing particles as well as dynamically positioning those particles in selected flow lamina within the downstream analysis channel. Through the independent adjustment of the three sheath inlet flows, the nozzle controlled the size of a focused stream for 6, 10, and 15 μm polystyrene microparticles. Additional flow adjustment allowed the nozzle to dynamically position the focused particle stream to a specific area within the downstream channel. This unique ability provides additional capability and sample flexibility to the system. In order to gain insight into the fluidic behavior of the system, experimental conditions and results were duplicated within 4.75 μm using a COMSOL Multiphysics(®) model to elucidate the structure, direction, proportion, and fate of fluid lamina throughout the nozzle region. The COMSOL Multiphysics model showed that the position and distribution of particles upon entering the nozzle have negligible influence over its focusing ability, extending the experimental results into a wider range of particle sizes and system flow rates. These results are promising for the application of this design to allow for a relatively simple, fast, fully fluidically controlled nozzle for selective particle focusing and positioning for further particle analysis and sorting.
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Affiliation(s)
- C G Hebert
- Naval Research Laboratory , Chemistry Division, Bio/Analytical Chemistry, Code 6112, 4555 Overlook Ave. S.W., Washington, District of Columbia 20375, USA
| | - S J R Staton
- National Research Council Postdoctoral Fellowship Program , Washington, District of Columbia 20375, USA
| | - T Q Hudson
- Naval Research Enterprise Internship Program (NREIP) , Washington, District of Columbia 20375, USA
| | - S J Hart
- LumaCyte , 1145 River Rd., Suite 16, Charlottesville, Virginia 22901, USA
| | - C Lopez-Mariscal
- ASEE Postdoctoral Fellowship Program, Washington , District of Columbia 20375, USA
| | - A Terray
- Naval Research Laboratory , Chemistry Division, Bio/Analytical Chemistry, Code 6112, 4555 Overlook Ave. S.W., Washington, District of Columbia 20375, USA
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29
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Haque M, Lee KKC, Ho S, Fernandes LA, Herman PR. Chemical-assisted femtosecond laser writing of lab-in-fibers. LAB ON A CHIP 2014; 14:3817-29. [PMID: 25120138 DOI: 10.1039/c4lc00648h] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The lab-on-chip (LOC) platform has presented a powerful opportunity to improve functionalization, parallelization, and miniaturization on planar or multilevel geometries that has not been possible with fiber optic technology. A migration of such LOC devices into the optical fiber platform would therefore open the revolutionary prospect of creating novel lab-in-fiber (LIF) systems on the basis of an efficient optical transport highway for multifunctional sensing. For the LIF, the core optical waveguide inherently offers a facile means to interconnect numerous types of sensing elements along the optical fiber, presenting a radical opportunity for optimizing the packaging and densification of diverse components in convenient geometries beyond that available with conventional LOCs. In this paper, three-dimensional patterning inside the optical fiber by femtosecond laser writing, together with selective chemical etching, is presented as a powerful tool to form refractive index structures such as optical waveguides and gratings as well as to open buried microfluidic channels and optical resonators inside the flexible and robust glass fiber. In this approach, optically smooth surfaces (~12 nm rms) are introduced for the first time inside the fiber cladding that precisely conform to planar nanograting structures when formed by aberration-free focusing with an oil-immersion lens across the cylindrical fiber wall. This process has enabled optofluidic components to be precisely embedded within the fiber to be probed by either the single-mode fiber core waveguide or the laser-formed optical circuits. We establish cladding waveguides, X-couplers, fiber Bragg gratings, microholes, mirrors, optofluidic resonators, and microfluidic reservoirs that define the building blocks for facile interconnection of inline core-waveguide devices with cladding optofluidics. With these components, more advanced, integrated, and multiplexed fiber microsystems are presented demonstrating fluorescence detection, Fabry-Perot interferometric refractometry, and simultaneous sensing of refractive index, temperature, and bending strain. The flexible writing technique and multiplexed sensors described here open powerful prospects to migrate the benefits of LOCs into a more flexible and miniature LIF platform for highly functional and distributed sensing capabilities. The waveguide backbone of the LIF inherently provides an efficient exchange of information, combining sensing data that are attractive in telecom networks, smart catheters for medical procedures, compact sensors for security and defense, shape sensors, and low-cost health care products.
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Affiliation(s)
- Moez Haque
- Department of Electrical and Computer Engineering, Institute for Optical Sciences, University of Toronto, 10 King's College Road, Toronto, Canada.
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30
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Spencer D, Elliott G, Morgan H. A sheath-less combined optical and impedance micro-cytometer. LAB ON A CHIP 2014; 14:3064-73. [PMID: 24964908 DOI: 10.1039/c4lc00224e] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
We describe a sheath-less micro-cytometer that measures four different parameters, namely fluorescence, large angle side scatter and dual frequency electrical impedance (electrical volume and opacity). The cytometer was benchmarked using both size and fluorescent bead standards and demonstrates excellent size accuracy (CVs ≤ 2.1%), sensitivity and dynamic range (3.5 orders of magnitude) at sample flow rates of 80 μL per minute. The cytometer was evaluated by analysing human blood, and a four part differential leukocyte assay for accurate CD4+ T-cell enumeration was demonstrated. The integration of impedance, fluorescence and side scatter into a single miniature cytometer platform provides the core information content of a classical cytometer in a highly compact, simple, portable and low cost format.
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Affiliation(s)
- Daniel Spencer
- Faculty of Physical Sciences and Engineering, and Institute for Life Sciences, University of Southampton, Southampton, Hampshire SO17 1BJ, UK.
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31
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Immunological Analyses of Whole Blood via “Microfluidic Drifting” Based Flow Cytometric Chip. Ann Biomed Eng 2014; 42:2303-13. [DOI: 10.1007/s10439-014-1041-5] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2014] [Accepted: 05/21/2014] [Indexed: 12/19/2022]
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32
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On-chip high-throughput manipulation of particles in a dielectrophoresis-active hydrophoretic focuser. Sci Rep 2014; 4:5060. [PMID: 24862936 PMCID: PMC4033927 DOI: 10.1038/srep05060] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2013] [Accepted: 05/07/2014] [Indexed: 11/08/2022] Open
Abstract
This paper proposes a novel concept of dielectrophoresis (DEP)-active hydrophoretic focusing of micro-particles and murine erythroleukemia (MEL) cells. The DEP-active hydrophoretic platform consists of crescent shaped grooves and interdigitated electrodes that generate lateral pressure gradients. These embedded electrodes exert a negative DEP force onto the particles by pushing them into a narrow space in the channel where the particle to groove interaction is intensive and hydrophoretic ordering occurs. Particles passing through the microfluidic device are directed towards the sidewalls of the channel. The critical limitation of DEP operating at a low flow rate and the specific hydrophoretic device for focusing particles of given sizes were overcome with the proposed microfluidic device. The focusing pattern can be modulated by varying the voltage. High throughput was achieved (maximum flow rate ~150 μL min(-1)) with good focusing performance. The non-spherical MEL cells were utilised to verify the effectiveness of the DEP-active hydrophoretic device.
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33
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Chen Y, Nawaz AA, Zhao Y, Huang PH, McCoy JP, Levine SJ, Wang L, Huang TJ. Standing surface acoustic wave (SSAW)-based microfluidic cytometer. LAB ON A CHIP 2014; 14:916-23. [PMID: 24406848 PMCID: PMC3956078 DOI: 10.1039/c3lc51139a] [Citation(s) in RCA: 73] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
The development of microfluidic chip-based cytometers has become an important area due to their advantages of compact size and low cost. Herein, we demonstrate a sheathless microfluidic cytometer which integrates a standing surface acoustic wave (SSAW)-based microdevice capable of 3D particle/cell focusing with a laser-induced fluorescence (LIF) detection system. Using SSAW, our microfluidic cytometer was able to continuously focus microparticles/cells at the pressure node inside a microchannel. Flow cytometry was successfully demonstrated using this system with a coefficient of variation (CV) of less than 10% at a throughput of ~1000 events s(-1) when calibration beads were used. We also demonstrated that fluorescently labeled human promyelocytic leukemia cells (HL-60) could be effectively focused and detected with our SSAW-based system. This SSAW-based microfluidic cytometer did not require any sheath flows or complex structures, and it allowed for simple operation over a wide range of sample flow rates. Moreover, with the gentle, bio-compatible nature of low-power surface acoustic waves, this technique is expected to be able to preserve the integrity of cells and other bioparticles.
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Affiliation(s)
- Yuchao Chen
- Department of Engineering Science and Mechanics, The Pennsylvania State University, University Park, PA 16802, USA.
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34
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Nawaz AA, Zhang X, Mao X, Rufo J, Lin SCS, Guo F, Zhao Y, Lapsley M, Li P, McCoy JP, Levine SJ, Huang TJ. Sub-micrometer-precision, three-dimensional (3D) hydrodynamic focusing via "microfluidic drifting". LAB ON A CHIP 2014; 14:415-23. [PMID: 24287742 PMCID: PMC3989543 DOI: 10.1039/c3lc50810b] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
In this article, we demonstrate single-layered, "microfluidic drifting" based three-dimensional (3D) hydrodynamic focusing devices with particle/cell focal positioning approaching submicron precision along both lateral and vertical directions. By systematically optimizing channel geometries and sample/sheath flow rates, a series of "microfluidic drifting" based 3D hydrodynamic focusing devices with different curvature angles are designed and fabricated. Their performances are then evaluated using confocal microscopy, fast camera imaging, and side-view imaging techniques. Using a device with a curvature angle of 180°, we have achieved a standard deviation of ±0.45 μm in particle focal position and a coefficient of variation (CV) of 2.37% in flow cytometric measurements. To the best of our knowledge, this is the best CV that has been achieved using a microfluidic flow cytometry device. Moreover, the device showed the capability to distinguish 8 peaks when subjected to a stringent 8-peak rainbow calibration test, signifying the ability to perform sensitive, accurate tests similar to commercial flow cytometers. We have further tested and validated our device by detection of HEK-293 cells. With its advantages in simple fabrication (i.e., single-layered device), precise 3D hydrodynamic focusing (i.e., submicrometer precision along both lateral and vertical directions), and high detection resolution (i.e., low CV), our method could serve as an important basis for high-performance, mass-producible microfluidic flow cytometry.
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Affiliation(s)
- Ahmad Ahsan Nawaz
- Department of Engineering Science and Mechanics, The Pennsylvania State University, University Park, PA 16802, USA.
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35
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Chiu YJ, Cho SH, Mei Z, Lien V, Wu TF, Lo YH. Universally applicable three-dimensional hydrodynamic microfluidic flow focusing. LAB ON A CHIP 2013; 13:1803-9. [PMID: 23493956 PMCID: PMC3654829 DOI: 10.1039/c3lc41202d] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
We have demonstrated a microfluidic device that can not only achieve three-dimensional flow focusing but also confine particles to the center stream along the channel. The device has a sample channel of smaller height and two sheath flow channels of greater height, merged into the downstream main channel where 3D focusing effects occur. We have demonstrated that both beads and cells in our device display significantly lower CVs in velocity and position distributions as well as reduced probability of coincidental events than they do in conventional 2D-confined microfluidic channels. The improved particle confinement in the microfluidic channel is highly desirable for microfluidic flow cytometers and in fluorescence-activated cell sorting (FACS). We have also reported a novel method to measure the velocity of each individual particle in the microfluidic channel. The method is compatible with the flow cytometer setup and requires no sophisticated visualization equipment. The principles and methods of device design and characterization can be applicable to many types of microfluidic systems.
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Affiliation(s)
- Yu-Jui Chiu
- Materials Science Program, University of California at San Diego, La Jolla, California 92093-0418, USA.
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36
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Microflow cytometers with integrated hydrodynamic focusing. SENSORS 2013; 13:4674-93. [PMID: 23571670 PMCID: PMC3673106 DOI: 10.3390/s130404674] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/01/2013] [Revised: 03/22/2013] [Accepted: 03/28/2013] [Indexed: 11/17/2022]
Abstract
This study demonstrates the suitability of microfluidic structures for high throughput blood cell analysis. The microfluidic chips exploit fully integrated hydrodynamic focusing based on two different concepts: Two-stage cascade focusing and spin focusing (vortex) principle. The sample--A suspension of micro particles or blood cells--is injected into a sheath fluid streaming at a substantially higher flow rate, which assures positioning of the particles in the center of the flow channel. Particle velocities of a few m/s are achieved as required for high throughput blood cell analysis. The stability of hydrodynamic particle positioning was evaluated by measuring the pulse heights distributions of fluorescence signals from calibration beads. Quantitative assessment based on coefficient of variation for the fluorescence intensity distributions resulted in a value of about 3% determined for the micro-device exploiting cascade hydrodynamic focusing. For the spin focusing approach similar values were achieved for sample flow rates being 1.5 times lower. Our results indicate that the performances of both variants of hydrodynamic focusing suit for blood cell differentiation and counting. The potential of the micro flow cytometer is demonstrated by detecting immunologically labeled CD3 positive and CD4 positive T-lymphocytes in blood.
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37
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Shi W, Guo L, Kasdan H, Tai YC. Four-part leukocyte differential count based on sheathless microflow cytometer and fluorescent dye assay. LAB ON A CHIP 2013; 13:1257-65. [PMID: 23389050 DOI: 10.1039/c3lc41059e] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
Leukocyte differential count is one of the most frequently ordered clinical tests in hospitals. This paper reports a point-of-care test for the leukocyte count by using a microflow cytometer and a fluorescent dye assay. The dye assay relied on fluorescent detection alone to count leukocytes in blood and to identify leukocyte subtypes. By combining the fluorescent assay with a sheathless microflow design, the proposed method achieved a minimal sample volume by eliminating excessive dilution and sheath flow. In this paper, a four-part leukocyte differential count including lymphocyte, monocyte, neutrophil and eosinophil was demonstrated, and the whole test consumed only a small amount of blood (5 μL) and reagents (68 μL in total). The merits of minimal sample volume, long reagent shelf life and portable instrument made this method optimal for point-of-care applications.
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Affiliation(s)
- Wendian Shi
- Caltech Micromachining Laboratory, Department of Electrical Engineering, California Institute of Technology, Pasadena, California 91125, USA
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38
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Das T, Chakraborty S. Perspective: Flicking with flow: Can microfluidics revolutionize the cancer research? BIOMICROFLUIDICS 2013; 7:11811. [PMID: 24403993 PMCID: PMC3574074 DOI: 10.1063/1.4789750] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/08/2012] [Accepted: 12/20/2012] [Indexed: 06/01/2023]
Abstract
According to the World Health Organization, cancer is one of the leading causes of death worldwide. Cancer research, in its all facets, is truly interdisciplinary in nature, cutting across the fields of fundamental and applied sciences, as well as biomedical engineering. In recent years, microfluidics has been applied successfully in cancer research. There remain, however, many elusive features of this disease, where microfluidic systems could throw new lights. In addition, some inherent features of microfluidic systems remain unexploited in cancer research. In this article, we first briefly review the advancement of microfluidics in cancer biology. We then describe the biophysical aspects of cancer and outline how microfluidic system could be useful in developing a deeper understanding on the underlying mechanisms. We next illustrate the effects of the confined environment of microchannel on cellular dynamics and argue that the tissue microconfinement could be a crucial facet in tumor development. Lastly, we attempt to highlight some of the most important problems in cancer biology, to inspire next level of microfluidic applications in cancer research.
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Affiliation(s)
- Tamal Das
- Department of New Materials and Biosystems, Max Planck Institute for Intelligent Systems, Stuttgart 70569, Germany
| | - Suman Chakraborty
- Department of Mechanical Engineering, Indian Institute for Technology Kharagpur, Kharagpur 721302, India
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39
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Kotz KT, Petrofsky AC, Haghgooie R, Granier R, Toner M, Tompkins RG. Inertial focusing cytometer with integrated optics for particle characterization. TECHNOLOGY 2013; 1:27-36. [PMID: 25346940 PMCID: PMC4206911 DOI: 10.1142/s233954781350009x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
Microfluidic inertial focusing has been shown as a simple and effective method to localize cells and particles within a flow cell for interrogation by an external optical system. To enable portable point of care optical cytometry, however, requires a reduction in the complexity of the large optical systems that are used in standard flow cytometers. Here, we present a new design that incorporates optical waveguides and focusing elements with an inertial focusing flow cell to make a compact robust cytometer capable of enumerating and discriminating beads, cells, and platelets.
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Affiliation(s)
- Kenneth T Kotz
- Department of Surgery, Massachusetts General Hospital, Harvard Medical School, Shriners Hospitals for Children, Boston, MA 02114, USA
| | - Anne C Petrofsky
- Department of Surgery, Massachusetts General Hospital, Harvard Medical School, Shriners Hospitals for Children, Boston, MA 02114, USA
| | - Ramin Haghgooie
- Department of Surgery, Massachusetts General Hospital, Harvard Medical School, Shriners Hospitals for Children, Boston, MA 02114, USA
| | - Robert Granier
- Department of Surgery, Massachusetts General Hospital, Harvard Medical School, Shriners Hospitals for Children, Boston, MA 02114, USA
| | - Mehmet Toner
- Department of Surgery, Massachusetts General Hospital, Harvard Medical School, Shriners Hospitals for Children, Boston, MA 02114, USA
| | - Ronald G Tompkins
- Department of Surgery, Massachusetts General Hospital, Harvard Medical School, Shriners Hospitals for Children, Boston, MA 02114, USA
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40
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Fan YJ, Wu YC, Chen Y, Kung YC, Wu TH, Huang KW, Sheen HJ, Chiou PY. Three dimensional microfluidics with embedded microball lenses for parallel and high throughput multicolor fluorescence detection. BIOMICROFLUIDICS 2013; 7:44121. [PMID: 24404054 PMCID: PMC3765297 DOI: 10.1063/1.4818944] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2013] [Accepted: 08/07/2013] [Indexed: 05/11/2023]
Abstract
We report a 3D microfluidic device with 32 detection channels and 64 sheath flow channels and embedded microball lens array for high throughput multicolor fluorescence detection. A throughput of 358 400 cells/s has been accomplished. This device is realized by utilizing solid immersion micro ball lens arrays for high sensitivity and parallel fluorescence detection. High refractive index micro ball lenses (n = 2.1) are embedded underneath PDMS channels close to cell detection zones in channels. This design permits patterning high N.A. micro ball lenses in a compact fashion for parallel fluorescence detection on a small footprint device. This device also utilizes 3D microfluidic fabrication to address fluid routing issues in two-dimensional parallel sheath focusing and allows simultaneous pumping of 32 sample channels and 64 sheath flow channels with only two inlets.
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Affiliation(s)
- Y J Fan
- Mechanical and Aerospace Engineering Department, University of California Los Angeles, Los Angeles, California 90095, USA ; Institute of Applied Mechanics, National Taiwan University, Taipei 10617, Taiwan
| | - Y C Wu
- Mechanical and Aerospace Engineering Department, University of California Los Angeles, Los Angeles, California 90095, USA
| | - Y Chen
- Mechanical and Aerospace Engineering Department, University of California Los Angeles, Los Angeles, California 90095, USA
| | - Y C Kung
- Mechanical and Aerospace Engineering Department, University of California Los Angeles, Los Angeles, California 90095, USA
| | - T H Wu
- Mechanical and Aerospace Engineering Department, University of California Los Angeles, Los Angeles, California 90095, USA ; Department of Pathology and Laboratory Medicine, University of California Los Angeles, Los Angeles, California 90095, USA
| | - K W Huang
- Mechanical and Aerospace Engineering Department, University of California Los Angeles, Los Angeles, California 90095, USA
| | - H J Sheen
- Institute of Applied Mechanics, National Taiwan University, Taipei 10617, Taiwan
| | - P Y Chiou
- Mechanical and Aerospace Engineering Department, University of California Los Angeles, Los Angeles, California 90095, USA ; Department of Bioengineering, University of California Los Angeles, Los Angeles, California 90095, USA
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41
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Watts BR, Zhang Z, Xu CQ, Cao X, Lin M. Integration of optical components on-chip for scattering and fluorescence detection in an optofluidic device. BIOMEDICAL OPTICS EXPRESS 2012; 3:2784-93. [PMID: 23162718 PMCID: PMC3493222 DOI: 10.1364/boe.3.002784] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2012] [Revised: 06/01/2012] [Accepted: 06/13/2012] [Indexed: 05/04/2023]
Abstract
An optofluidic device is demonstrated with photonic components integrated onto the chip for use in fluorescence and scatter detection and counting applications. The device is fabricated by integrating the optical and fluidic components in a single functional layer. Optical excitation on-chip is accomplished via a waveguide integrated with a system of lenses that reforms the geometry of the beam in the microfluidic channel into a specific shape that is more suitable for reliable detection. Separate counting tests by detecting fluorescence and scattered signals from 2.5 and 6.0 μm beads were performed and found to show detection reliability comparable to that of conventional means of excitation and an improvement over other microchip-based designs.
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Affiliation(s)
- Benjamin R Watts
- Department of Engineering Physics, McMaster University, Hamilton, Ontario L8S 4L7, Canada
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42
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Fu LM, Wang YN. Optical microflow cytometer based on external total reflection. Electrophoresis 2012; 33:3229-35. [DOI: 10.1002/elps.201200223] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2012] [Revised: 06/19/2012] [Accepted: 07/10/2012] [Indexed: 11/08/2022]
Affiliation(s)
- Lung-Ming Fu
- Department of Materials Engineering; National Pingtung University of Science and Technology; Pingtung; Taiwan
| | - Yao-Nan Wang
- Department of Vehicle Engineering; National Pingtung University of Science and Technology; Pingtung; Taiwan
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43
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Yang RJ, Hou HH, Wang YN, Lin CH, Fu LM. A hydrodynamic focusing microchannel based on micro-weir shear lift force. BIOMICROFLUIDICS 2012; 6:34110. [PMID: 23919100 PMCID: PMC3427323 DOI: 10.1063/1.4739073] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/22/2012] [Accepted: 07/10/2012] [Indexed: 05/23/2023]
Abstract
A novel microflow cytometer is proposed in which the particles are focused in the horizontal and vertical directions by means of the Saffman shear lift force generated within a micro-weir microchannel. The proposed device is fabricated on stress-relieved glass substrates and is characterized both numerically and experimentally using fluorescent particles with diameters of 5 μm and 10 μm, respectively. The numerical results show that the micro-weir structures confine the particle stream to the center of the microchannel without the need for a shear flow. Moreover, the experimental results show that the particles emerging from the micro-weir microchannel pass through the detection region in a one-by-one fashion. The focusing effect of the micro-weir microchannel is quantified by computing the normalized variance of the optical detection signal intensity. It is shown that the focusing performance of the micro-weir structure is equal to 99.76% and 99.57% for the 5-μm and 10-μm beads, respectively. Overall, the results presented in this study confirm that the proposed microcytometer enables the reliable sorting and counting of particles with different diameters.
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Affiliation(s)
- Ruey-Jen Yang
- Department of Engineering Science, National Cheng Kung University, Tainan 70101, Taiwan
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44
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Kettlitz SW, Valouch S, Sittel W, Lemmer U. Flexible planar microfluidic chip employing a light emitting diode and a PIN-photodiode for portable flow cytometers. LAB ON A CHIP 2012; 12:197-203. [PMID: 22086498 DOI: 10.1039/c1lc20672a] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Detection of fluorescence particles is a key method of flow cytometry. We evaluate the performance of a design for a microfluidic fluorescence particle detection device. Due to the planar design with low layer thicknesses, we avoid optical components such as lenses or dichroic mirrors and substitute them with a shadow mask and colored film filters. A commercially available LED is used as the light source and a PIN-photodiode as detector. This design approach reduces component cost and power consumption and enables supplying the device with power from a standard USB port. From evaluation of this design, we obtain a maximum particle detection frequency of up to 600 particles per second at a sensitivity of better than 4.7 × 10(5) MESF (molecules of equivalent soluble fluorochrome) measured with particles for FITC sensitivity calibration. Lowering the flow rate increases the instrument sensitivity by an order of magnitude enabling the detection of particles with 4.5 × 10(4) MESF.
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Affiliation(s)
- Siegfried W Kettlitz
- Light Technology Institute, Karlsruhe Institute of Technology, Kaiserstr. 12 Geb. 30.34, Karlsruhe, Baden-Württemberg 76131, Germany.
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45
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Kennedy MJ, Ladouceur HD, Moeller T, Kirui D, Batt CA. Analysis of a laminar-flow diffusional mixer for directed self-assembly of liposomes. BIOMICROFLUIDICS 2012; 6:44119. [PMID: 24348890 PMCID: PMC3555636 DOI: 10.1063/1.4772602] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/07/2012] [Accepted: 12/04/2012] [Indexed: 05/15/2023]
Abstract
The present work describes the operation and simulation of a microfluidic laminar-flow mixer. Diffusive mixing takes place between a core solution containing lipids in ethanol and a sheath solution containing aqueous buffer, leading to self assembly of liposomes. Present device architecture hydrodynamically focuses the lipid solution into a cylindrical core positioned at the center of a microfluidic channel of 125 × 125-μm(2) cross-section. Use of the device produces liposomes in the size range of 100-300 nm, with larger liposomes forming at greater ionic strength in the sheath solution and at lower lipid concentration in the core solution. Finite element simulations compute the concentration distributions of solutes at axial distances of greater than 100 channel widths. These simulations reduce computation time and enable computation at long axial distances by utilizing long hexahedral elements in the axial flow region and fine tetrahedral elements in the hydrodynamic focusing region. Present meshing technique is generally useful for simulation of long microfluidic channels and is fully implementable using comsol Multiphysics. Confocal microscopy provides experimental validation of the simulations using fluorescent solutions containing fluorescein or enhanced green fluorescent protein.
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Affiliation(s)
- Matthew J Kennedy
- NRC Research Associate at Naval Research Laboratory, Chemistry Division, Washington, DC 20375, USA ; Department of Electrical and Computer Engineering, Cornell University, Ithaca, New York 14853, USA
| | - Harold D Ladouceur
- Naval Research Laboratory, Chemistry Division, Washington, DC 20375, USA
| | - Tiffany Moeller
- Department of Food Science, Cornell University, Ithaca, New York 14853, USA
| | - Dickson Kirui
- Department of Biomedical Engineering, Cornell University, Ithaca, New York 14853, USA
| | - Carl A Batt
- Department of Food Science, Cornell University, Ithaca, New York 14853, USA
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46
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Pagliara S, Chimerel C, Langford R, Aarts DGAL, Keyser UF. Parallel sub-micrometre channels with different dimensions for laser scattering detection. LAB ON A CHIP 2011; 11:3365-3368. [PMID: 21804971 DOI: 10.1039/c1lc20399a] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
A novel and simple approach for the realization of polymer sub-micrometre channels is introduced by exploiting replica molding of Pt wires deposited by focused ion beam. We fabricate arrays of parallel channels with typical dimensions down to 600 nm and with variable height. We characterize the pressure-driven transport of polymer colloids through the channels in terms of the translocation frequency, amplitude and duration by implementing a laser scattering detection technique. We propose a prototype application of the presented platform such as the in situ sizing and sensing of populations of particles with different dimensions down to 50 nm.
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Affiliation(s)
- Stefano Pagliara
- University of Cambridge, Cavendish Laboratory, Cambridge, CB3 0HE, United Kingdom
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47
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Zhu S, Wang S, Yang L, Huang T, Yan X. Progress in the development of techniques based on light scattering for single nanoparticle detection. Sci China Chem 2011. [DOI: 10.1007/s11426-011-4313-z] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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48
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Kim Y, Joshi SD, Davidson LA, LeDuc PR, Messner WC. Dynamic control of 3D chemical profiles with a single 2D microfluidic platform. LAB ON A CHIP 2011; 11:2182-2188. [PMID: 21528131 DOI: 10.1039/c1lc20077a] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Dynamic control of three-dimensional (3D) chemical patterns with both high precision and high speed is important in a range of applications from chemical synthesis, flow cytometry, and multi-scale biological manipulation approaches. A central challenge in controlling 3D chemical patterns is the inability to create rapidly tunable 3D profiles with simple and direct approaches that avoid complicated microfabrication. Here, we present the ability to rapidly and precisely create 3D chemical patterns using a single two-dimensional (2D) microfluidic platform. We are not only able to create these 3D patterns, but can rapidly switch from one mode to another (e.g. from a focused to a defocused pattern in less than 1 second) via simple changes in inlet pressures. A feedback control scheme with a pressure modulation mechanism controls the pressure changes. In addition to experiments, we conducted computational simulations for guiding the optimum design of the channels as well as revealing the sensitivity of the patterns to the channel dimensions; these simulations have high experimental correlations. We also show that microvortices play an important role in creating these tunable 3D patterns in this microfluidic platform. We quantitatively determine the degrees of the focused patterns in 2D cross-sections using a focus index with a 2D Gaussian function. Our integrated approach combining feedback control with simple microfluidics will be useful for researchers in diverse disciplines including chemistry, engineering, physics, and biology.
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Affiliation(s)
- YongTae Kim
- Department of Mechanical Engineering, Carnegie Mellon University, 5000 Forbes Ave., Pittsburgh, PA 15213, USA
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49
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Frankowski M, Bock N, Kummrow A, Schädel-Ebner S, Schmidt M, Tuchscheerer A, Neukammer J. A microflow cytometer exploited for the immunological differentiation of leukocytes. Cytometry A 2011; 79:613-24. [PMID: 21618424 DOI: 10.1002/cyto.a.21083] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2010] [Revised: 04/01/2011] [Accepted: 04/28/2011] [Indexed: 11/11/2022]
Abstract
In this article, we demonstrate the potential of a microfluidic chip for the differentiation of immunologically stained blood cells. To this end, white blood cells stained with antibodies typically applied for the determination of the immune status were measured in the micro-device. Relative concentrations of lymphocytes and subpopulations of lymphocytes are compared to those obtained with a conventional flow cytometer. The stability of the hydrodynamic focusing and the optical setup was determined by measuring the variation of the signal pulse height of fluorescence calibration beads, being about 2% for the micro-device. This value and the overall performance of the micro-device are similar to conventional flow cytometers. It follows from our results that such microfluidic structures are well suited as modules in a compact, portable read-out instrument. The production process of the microflow cytometers, which we exploited for immunological cell differentiation, is compatible with mass production technology like injection molding and, hence, low cost disposable chips could be available in the future.
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50
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Rodríguez-Villarreal AI, Tarn MD, Madden LA, Lutz JB, Greenman J, Samitier J, Pamme N. Flow focussing of particles and cells based on their intrinsic properties using a simple diamagnetic repulsion setup. LAB ON A CHIP 2011; 11:1240-8. [PMID: 21186390 DOI: 10.1039/c0lc00464b] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
The continuous flow focussing and manipulation of particles and cells are important factors in microfluidic applications for performing accurate and reproducible procedures downstream. Many particle focussing methods require complex setups or channel designs that can limit the process and its applications. Here, we present diamagnetic repulsion as a simple means of focussing objects in continuous flow, based only on their intrinsic properties without the requirement of any label. Diamagnetic polystyrene particles were suspended in a paramagnetic medium and pumped through a capillary between a pair of permanent magnets, whereupon the particles were repelled by each magnet into the central axis of the capillary, thus achieving focussing. By investigating this effect, we found that the focussing was greatly enhanced with (i) increased magnetic susceptibility of the medium, (ii) reduced flow rate of the suspension, (iii) increased particle size, and (iv) increased residence time in the magnetic field. Furthermore, we applied diamagnetic repulsion to the flow focussing of living, label-free HaCaT cells.
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