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Amiroudine S, Demekhin EA, Shelistov VS, Ganchenko GS. Electric-permittivity-based instability of two dielectric miscible liquids under DC field. THE EUROPEAN PHYSICAL JOURNAL. E, SOFT MATTER 2022; 45:1. [PMID: 34978626 DOI: 10.1140/epje/s10189-021-00157-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/07/2021] [Accepted: 12/17/2021] [Indexed: 06/14/2023]
Abstract
This paper considers the mixing of two dielectric miscible viscous liquids with different electric permittivities bounded by solid walls in an external electric field normal to the interface of the liquids. The mutual diffusion of these two liquids leads to the formation of an unsteady self-similar 1D diffusion layer. This layer is found to be unstable to the perturbations of the interface. A special sophisticated mathematical approach in self-similar variables is developed to estimate its stability. The results of a linear stability theory are verified by direct numerical simulations of the full nonlinear problem. A mixing efficiency based on the separation amplitude and an optimal electric field strength to achieve the fastest mixing are proposed in the present study.
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Affiliation(s)
- S Amiroudine
- Institute of Mechanics and Engineering (I2M) CNRS, University of Bordeaux, 33400, Talence, France.
| | - E A Demekhin
- Department of Mathematics and Computer Science, Financial University, Krasnodar, Russian Federation, 350051
- Laboratory of Micro- and Nanoscale Electro- and Hydrodynamics, Financial University, Krasnodar, Russian Federation, 350051
- Laboratory of General Aeromechanics, Institute of Mechanics, Moscow State University, Moscow, Russian Federation, 119192
| | - V S Shelistov
- Laboratory of Micro- and Nanoscale Electro- and Hydrodynamics, Financial University, Krasnodar, Russian Federation, 350051
| | - G S Ganchenko
- Laboratory of Micro- and Nanoscale Electro- and Hydrodynamics, Financial University, Krasnodar, Russian Federation, 350051
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2
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Demekhin EA, Ganchenko GS, Gorbacheva EV, Amiroudine S. Stability of two layers dielectric-electrolyte microflow subjected to an alternating external electric field. Electrophoresis 2018; 39:1777-1785. [PMID: 29660146 DOI: 10.1002/elps.201700472] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2017] [Revised: 03/17/2018] [Accepted: 04/07/2018] [Indexed: 11/11/2022]
Abstract
The stability of the electroosmotic flow of the two-phase system electrolyte-dielectric with a free interface in the microchannel under an external electric field is examined theoretically. The mathematical model includes the Nernst-Plank equations for the ion concentrations. The linear stability of the 1D nonstationary solution with respect to the small, periodic perturbations along the channel, is studied. Two types of instability have been highlighted. The first is known as the long-wave instability and is connected with the distortion of the free charge on the interface. In the long-wave area, the results are in good agreement with the ones obtained theoretically and experimentally in the literature. The second type of instability is a short-wave and mostly connected with the disturbance of the electrolyte conductivity. The short-wave type of instability has not been found previously in the literature and constitutes the basis and the strength of the present work. It is revealed that with the increase of the external electric field frequency, the 1D flow is stabilized. The dependence of the flow on the other parameters of the system is qualitatively the same as for the constant electric field.
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Affiliation(s)
- Evgeny A Demekhin
- Laboratory of Micro- and Nanoscale Electro- and Hydrodynamics, Financial University under the Government of the Russian Federation, Krasnodar, Russian Federation
- Laboratory of General Aeromechanics, Institute of Mechanics, Moscow State University, Moscow, Russian Federation
| | - Georgy S Ganchenko
- Laboratory of Micro- and Nanoscale Electro- and Hydrodynamics, Financial University under the Government of the Russian Federation, Krasnodar, Russian Federation
| | - Ekaterina V Gorbacheva
- Department of Applied Mathematics, Kuban State University, Krasnodar, Russian Federation
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3
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Bissonnette L, Bergeron MG. Next revolution in the molecular theranostics of infectious diseases: microfabricated systems for personalized medicine. Expert Rev Mol Diagn 2014; 6:433-50. [PMID: 16706745 DOI: 10.1586/14737159.6.3.433] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The molecular diagnosis of infectious diseases is currently going through a revolution sustained by the regulatory approval of amplification tests that have been shown to be equivalent or superior to existing gold standard methods. The recent approval of a microarray system for the pharmacogenomic profiling of cytochrome P450-mediated drug metabolism is paving the way to novel, rapid, sensitive, robust and economical microfabricated systems for point-of-care diagnostics, which are utilized closer and closer to the patient's bedside. These systems will enable the multiparametric genetic evaluation of several medical conditions, including infectious diseases. This forecoming revolution will position molecular theranostics in a broader integrated view of personalized medicine, which exploits genetic information from microbes and human hosts to optimize patient management and disease treatment.
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Affiliation(s)
- Luc Bissonnette
- Département de Biologie Médicale (Microbiologie), Faculté de Médecine, Université Laval, Québec City, Canada.
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4
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Langenkamp E, Kamps JAAM, Mrug M, Verpoorte E, Niyaz Y, Horvatovich P, Bischoff R, Struijker-Boudier H, Molema G. Innovations in studying in vivo cell behavior and pharmacology in complex tissues--microvascular endothelial cells in the spotlight. Cell Tissue Res 2013; 354:647-69. [PMID: 24072341 DOI: 10.1007/s00441-013-1714-7] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2013] [Accepted: 07/18/2013] [Indexed: 02/06/2023]
Abstract
Many studies on the molecular control underlying normal cell behavior and cellular responses to disease stimuli and pharmacological intervention are conducted in single-cell culture systems, while the read-out of cellular engagement in disease and responsiveness to drugs in vivo is often based on overall tissue responses. As the majority of drugs under development aim to specifically interact with molecular targets in subsets of cells in complex tissues, this approach poses a major experimental discrepancy that prevents successful development of new therapeutics. In this review, we address the shortcomings of the use of artificial (single) cell systems and of whole tissue analyses in creating a better understanding of cell engagement in disease and of the true effects of drugs. We focus on microvascular endothelial cells that actively engage in a wide range of physiological and pathological processes. We propose a new strategy in which in vivo molecular control of cells is studied directly in the diseased endothelium instead of at a (far) distance from the site where drugs have to act, thereby accounting for tissue-controlled cell responses. The strategy uses laser microdissection-based enrichment of microvascular endothelium which, when combined with transcriptome and (phospho)proteome analyses, provides a factual view on their status in their complex microenvironment. Combining this with miniaturized sample handling using microfluidic devices enables handling the minute sample input that results from this strategy. The multidisciplinary approach proposed will enable compartmentalized analysis of cell behavior and drug effects in complex tissue to become widely implemented in daily biomedical research and drug development practice.
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Affiliation(s)
- Elise Langenkamp
- University Medical Center Groningen, Department of Pathology and Medical Biology, Medical Biology section, University of Groningen, Groningen, The Netherlands
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5
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Manage DP, Elliott DG, Backhouse CJ. Millimeter scale separation of DNA with a replaceable polymer matrix. Electrophoresis 2012; 33:3213-21. [PMID: 23027089 DOI: 10.1002/elps.201200188] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2012] [Revised: 07/10/2012] [Accepted: 07/11/2012] [Indexed: 12/16/2022]
Abstract
Electrophoresis is a powerful method that has seen a wide range of applications, often in automated genetic diagnostic instruments that require the use of a replaceable sieving matrix. The power and simplicity of electrophoresis as an analysis technique would be ideal for highly integrated and low-cost analysis systems if the method could be implemented in microfluidics on the scale of several mm. We demonstrate the electrophoretic analysis of DNA with separation lengths as small as 2 mm and with a resolution adequate for the analysis of PCR products, i.e. resolutions of 10-20 base pairs. Such small-scale separations enable analysis systems consisting of microfluidics and microelectronics integrated into a single inexpensive package, thereby overcoming a key challenge facing the development of the lab on chip technologies.
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Affiliation(s)
- Dammika P Manage
- Department of Electrical and Computer Engineering, University of Alberta, Edmonton, Alberta, Canada
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Elfimova N, Amer W, Odenthal M. Analysis of microsatellite instability by microfluidic-based electrophoresis. Methods Mol Biol 2012; 919:287-96. [PMID: 22976109 DOI: 10.1007/978-1-62703-029-8_25] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/21/2023]
Abstract
Microsatellites are short repetitive sequences of two, three, or four bases, prone to base mispairing. Microsatellite instability (MSI) occurs frequently in various types of cancer due to a defective DNA mismatch repair system. Therefore, MSI analysis is an important tool in clinical research and molecular diagnostics. Mostly, polyacrylamide gel electrophoresis or capillary electrophoresis of labeled microsatellite sequences is used for the detection of MSI. Here we present a microfluidic-based electrophoresis technology for MSI analyses. Defined loci of microsatellites were PCR amplified and amplicons were analyzed by microfluidic-based electrophoresis. The electropherogram profiles of tumor and non-tumor derived DNA clearly revealed an individual pattern identifying differences in tumor-associated microsatellites. Detection of MSI by microfluidics turned out to be a simple and efficient procedure but less laborious than conventional approaches. Thus, the chip-based microfluidic electrophoresis is a simple, reliable, and robust technology for MSI detection, which allows label-free analyses of microsatellite amplicons within 30 min.
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Affiliation(s)
- Natalia Elfimova
- Institute for Pathology, University of Cologne, Cologne, Germany
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7
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Duarte GRM, Coltro WKT, Borba JC, Price CW, Landers JP, Carrilho E. Disposable polyester-toner electrophoresis microchips for DNA analysis. Analyst 2012; 137:2692-8. [PMID: 22545263 DOI: 10.1039/c2an16220b] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Microchip electrophoresis has become a powerful tool for DNA separation, offering all of the advantages typically associated with miniaturized techniques: high speed, high resolution, ease of automation, and great versatility for both routine and research applications. Various substrate materials have been used to produce microchips for DNA separations, including conventional (glass, silicon, and quartz) and alternative (polymers) platforms. In this study, we perform DNA separation in a simple and low-cost polyester-toner (PeT)-based electrophoresis microchip. PeT devices were fabricated by a direct-printing process using a 600 dpi-resolution laser printer. DNA separations were performed on PeT chip with channels filled with polymer solutions (0.5% m/v hydroxyethylcellulose or hydroxypropylcellulose) at electric fields ranging from 100 to 300 V cm(-1). Separation of DNA fragments between 100 and 1000 bp, with good correlation of the size of DNA fragments and mobility, was achieved in this system. Although the mobility increased with increasing electric field, separations showed the same profile regardless of the electric field. The system provided good separation efficiency (215,000 plates per m for the 500 bp fragment) and the separation was completed in 4 min for 1000 bp fragment ladder. The cost of a given chip is approximately $0.15 and it takes less than 10 minutes to prepare a single device.
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Affiliation(s)
- Gabriela R M Duarte
- Instituto de Química de São Carlos, Universidade de São Paulo, Grupo de Bioanalítica, Microfabricação e Separações, Brazil
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8
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Wagler PF, Tangen U, Maeke T, McCaskill JS. Field programmable chemistry: integrated chemical and electronic processing of informational molecules towards electronic chemical cells. Biosystems 2012; 109:2-17. [PMID: 22309763 DOI: 10.1016/j.biosystems.2012.01.005] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2011] [Accepted: 01/09/2012] [Indexed: 12/13/2022]
Abstract
The topic addressed is that of combining self-constructing chemical systems with electronic computation to form unconventional embedded computation systems performing complex nano-scale chemical tasks autonomously. The hybrid route to complex programmable chemistry, and ultimately to artificial cells based on novel chemistry, requires a solution of the two-way massively parallel coupling problem between digital electronics and chemical systems. We present a chemical microprocessor technology and show how it can provide a generic programmable platform for complex molecular processing tasks in Field Programmable Chemistry, including steps towards the grand challenge of constructing the first electronic chemical cells. Field programmable chemistry employs a massively parallel field of electrodes, under the control of latched voltages, which are used to modulate chemical activity. We implement such a field programmable chemistry which links to chemistry in rather generic, two-phase microfluidic channel networks that are separated into weakly coupled domains. Electric fields, produced by the high-density array of electrodes embedded in the channel floors, are used to control the transport of chemicals across the hydrodynamic barriers separating domains. In the absence of electric fields, separate microfluidic domains are essentially independent with only slow diffusional interchange of chemicals. Electronic chemical cells, based on chemical microprocessors, exploit a spatially resolved sandwich structure in which the electronic and chemical systems are locally coupled through homogeneous fine-grained actuation and sensor networks and play symmetric and complementary roles. We describe how these systems are fabricated, experimentally test their basic functionality, simulate their potential (e.g. for feed forward digital electrophoretic (FFDE) separation) and outline the application to building electronic chemical cells.
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9
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Microfluidic circuit analysis I: Ion current relationships for thin slits and pipes. J Colloid Interface Sci 2012; 365:1-15. [DOI: 10.1016/j.jcis.2011.07.076] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2011] [Accepted: 07/23/2011] [Indexed: 11/19/2022]
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10
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Choi S, Goryll M, Sin LYM, Wong PK, Chae J. Microfluidic-based biosensors toward point-of-care detection of nucleic acids and proteins. MICROFLUIDICS AND NANOFLUIDICS 2011; 10:231-247. [PMID: 32214951 PMCID: PMC7087901 DOI: 10.1007/s10404-010-0638-8] [Citation(s) in RCA: 133] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/12/2010] [Accepted: 04/26/2010] [Indexed: 05/14/2023]
Abstract
This article reviews state-of-the-art microfluidic biosensors of nucleic acids and proteins for point-of-care (POC) diagnostics. Microfluidics is capable of analyzing small sample volumes (10-9-10-18 l) and minimizing costly reagent consumption as well as automating sample preparation and reducing processing time. The merger of microfluidics and advanced biosensor technologies offers new promises for POC diagnostics, including high-throughput analysis, portability and disposability. However, this merger also imposes technological challenges on biosensors, such as high sensitivity and selectivity requirements with sample volumes orders of magnitude smaller than those of conventional practices, false response errors due to non-specific adsorption, and integrability with other necessary modules. There have been many prior review articles on microfluidic-based biosensors, and this review focuses on the recent progress in last 5 years. Herein, we review general technologies of DNA and protein biosensors. Then, recent advances on the coupling of the biosensors to microfluidics are highlighted. Finally, we discuss the key challenges and potential solutions for transforming microfluidic biosensors into POC diagnostic applications.
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Affiliation(s)
- Seokheun Choi
- School of Electrical, Computer and Energy Engineering, Arizona State University, Tempe, AZ 85287 USA
| | - Michael Goryll
- School of Electrical, Computer and Energy Engineering, Arizona State University, Tempe, AZ 85287 USA
| | - Lai Yi Mandy Sin
- Department of Aerospace and Mechanical Engineering, University of Arizona, Tucson, AZ 85721 USA
| | - Pak Kin Wong
- Department of Aerospace and Mechanical Engineering, University of Arizona, Tucson, AZ 85721 USA
| | - Junseok Chae
- School of Electrical, Computer and Energy Engineering, Arizona State University, Tempe, AZ 85287 USA
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11
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Ni Y, Dou X, Cheng S, Zhu Y. Design of separation length and electric field strength for high-speed DNA electrophoresis. Electrophoresis 2010; 32:238-45. [DOI: 10.1002/elps.201000404] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2010] [Revised: 10/16/2010] [Accepted: 10/22/2010] [Indexed: 01/01/2023]
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12
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Odenthal M, Barta N, Lohfink D, Drebber U, Schulze F, Dienes HP, Baldus SE. Analysis of microsatellite instability in colorectal carcinoma by microfluidic-based chip electrophoresis. J Clin Pathol 2008; 62:850-2. [PMID: 18641409 PMCID: PMC2727801 DOI: 10.1136/jcp.2008.056994] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Microsatellite analysis is an important tool in clinical research and molecular diagnostics because microsatellite instability (MSI) occurs frequently in various types of cancer. Approximately 10–15% of colorectal, gastric and endometrial carcinomas are associated with MSI, and this has an impact on clinical prognosis. The microsatellite loci Bat25, Bat26, D2S123, D5S346 and D17S250, recommended by the Bethesda guidelines, were analysed by microfluidic-based on-chip electrophoresis in 40 cases of colon carcinoma with known MSI status. In all cases, microfluidic separation of the PCR amplicons resulted in highly resolved, distinct patterns of each of the five microsatellite loci. Detection of MSI could be demonstrated by microsatellite-loci-associated, well-defined deviations in the electropherogram profiles of tumour and non-tumour material, and confirmed the classification of MSI cases performed by conventional technology. In conclusion, microfluidic chip technology is a simple and reliable approach for MSI detection that allows label-free and very fast analysis of microsatellite amplicons.
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Affiliation(s)
- M Odenthal
- Institute of Pathology, University Hospital of Cologne, Germany.
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13
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Abstract
Planar microfluidic devices have emerged as effective tools for the electrophoretic separation of a variety of different DNA inputs. The advancement of this miniaturized platform was inspired initially by demands placed on electrophoretic performance metrics by the human genome project and has provided a viable alternative to slab gel and even capillary formats due to its ability to offer high resolution separations of nucleic acid materials in a fraction of the time associated with its predecessors, consumption of substantially less sample and reagents while maintaining the ability to perform many separations in parallel for realizing ultra-high throughputs. Another compelling advantage of this separation platform is that it offers the potential for integrating front-end sample preprocessing steps onto the separation device eliminating the need for manual sample handling. This review aims to compile a recent survey of various electrophoretic separations using either glass or polymer-based microchips in the areas of genotyping and DNA sequencing as well as those involving the growing field of DNA-based forensics.
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Affiliation(s)
- Rondedrick Sinville
- Department of Chemistry, Louisiana State University, Baton Rouge, LA 70803, USA
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14
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Mohanty SK, Kim D, Beebe DJ. Do-it-yourself microelectrophoresis chips with integrated sample recovery. Electrophoresis 2007; 27:3772-8. [PMID: 16960842 DOI: 10.1002/elps.200600238] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
We present a microelectrophoresis chip that is simple to fabricate using the microfluidic tectonics (microFT) platform (Beebe, D. J. et al., Proc. Natl. Acad. Sci. USA 2000, 97, 13488-13493; Agarwal, A. K. et al.,. J. Micromech. Microeng. 2006, 16, 332-340). The device contains a removable capillary insert (RCI) for easy sample collection after separation (Atencia, J. et al.,. Lab Chip 2006, DOI: 10. 1039/b514068d). Device construction is accomplished in less than 20 min without specialized equipment traditionally associated with microelectrophoresis chip construction. microFT was used to build a PAGE device utilizing two orthogonal microchannels. One channel performs standard separations, while the second channel serves as an access point to remove bands of interest from the chip via the RCI. The RCI contains an integrated electrode that facilitates the removal of bands using electrokinetic techniques. The device was characterized using prestained proteins (Pierce BlueRanger and TriChromRanger). Samples were loaded into the microelectrophoresis device via a standard micropipette. An electrical field of 40 V/cm was used to separate and collect the proteins. The microPAGE device is simple to fabricate, benefits from microscale analysis, and includes an on-chip collection scheme that interfaces the macroworld with the microworld.
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Affiliation(s)
- Swomitra K Mohanty
- Department of Biomedical Engineering, University of Wisconsin-Madison, Madison, WI, USA.
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15
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Fredlake CP, Hert DG, Mardis ER, Barron AE. What is the future of electrophoresis in large-scale genomic sequencing? Electrophoresis 2006; 27:3689-702. [PMID: 17031784 DOI: 10.1002/elps.200600408] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Although a finished human genome reference sequence is now available, the ability to sequence large, complex genomes remains critically important for researchers in the biological sciences, and in particular, continued human genomic sequence determination will ultimately help to realize the promise of medical care tailored to an individual's unique genetic identity. Many new technologies are being developed to decrease the costs and to dramatically increase the data acquisition rate of such sequencing projects. These new sequencing approaches include Sanger reaction-based technologies that have electrophoresis as the final separation step as well as those that use completely novel, nonelectrophoretic methods to generate sequence data. In this review, we discuss the various advances in sequencing technologies and evaluate the current limitations of novel methods that currently preclude their complete acceptance in large-scale sequencing projects. Our primary goal is to analyze and predict the continuing role of electrophoresis in large-scale DNA sequencing, both in the near and longer term.
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Affiliation(s)
- Christopher P Fredlake
- Department of Chemical and Biological Engineering, Northwestern University, Evanston, IL, USA
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16
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Chen Z, Burns MA. Effect of buffer flow on DNA separation in a microfabricated electrophoresis system. Electrophoresis 2005; 26:4718-28. [PMID: 16294296 DOI: 10.1002/elps.200500579] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
An adequate buffer reservoir is one essential component of an electrophoresis system, providing current carrying ions and maintaining constant pH. In a microfabricated DNA separation system with on-chip electrodes, the amount of buffer used is limited by the design of the device; the buffer continuity can be easily disturbed by the production of bubbles. Continuously flowing 1 x Tris-borate-EDTA (TBE) buffer over the electrodes at the cathodic end solves both problems. This flow increases the resolution for ssDNA primer separations (21 and 25 bases) to a maximum value of 1.4 within a distance of 1.2 cm, about four times higher than that without flow. Similar improvement has been achieved for dsDNA separation (20 bp ladder; BioRad) at a distance of only 0.4 cm, giving baseline resolution for bands from 20 to 240 bp. We have also investigated the effect of buffer concentration on resolution, and no similar improvement can be obtained by merely increasing the buffer concentration without flow.
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Affiliation(s)
- Zheng Chen
- Department of Chemical Engineering, The University of Michigan, Ann Arbor, MI 48109-2136, USA
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17
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Pal R, Yang M, Lin R, Johnson BN, Srivastava N, Razzacki SZ, Chomistek KJ, Heldsinger DC, Haque RM, Ugaz VM, Thwar PK, Chen Z, Alfano K, Yim MB, Krishnan M, Fuller AO, Larson RG, Burke DT, Burns MA. An integrated microfluidic device for influenza and other genetic analyses. LAB ON A CHIP 2005; 5:1024-32. [PMID: 16175256 DOI: 10.1039/b505994a] [Citation(s) in RCA: 81] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
An integrated microfluidic device capable of performing a variety of genetic assays has been developed as a step towards building systems for widespread dissemination. The device integrates fluidic and thermal components such as heaters, temperature sensors, and addressable valves to control two nanoliter reactors in series followed by an electrophoretic separation. This combination of components is suitable for a variety of genetic analyses. As an example, we have successfully identified sequence-specific hemagglutinin A subtype for the A/LA/1/87 strain of influenza virus. The device uses a compact design and mass production technologies, making it an attractive platform for a variety of widely disseminated applications.
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Affiliation(s)
- R Pal
- Department of Chemical Engineering, University of Michigan, Ann Arbor, MI 48109, USA
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18
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Ottino JM, Wiggins S. Introduction: mixing in microfluidics. PHILOSOPHICAL TRANSACTIONS. SERIES A, MATHEMATICAL, PHYSICAL, AND ENGINEERING SCIENCES 2004; 362:923-35. [PMID: 15306477 DOI: 10.1098/rsta.2003.1355] [Citation(s) in RCA: 185] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
In this paper we briefly review the main issues associated with mixing at the microscale and introduce the papers comprising the Theme Issue.
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Affiliation(s)
- Julio M Ottino
- Department of Chemical and Biological Engineering, R. R. McCormick School of Engineering and Applied Sciences, Northwestern University, Evanston, IL 60208, USA.
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