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Ulep TH, Day AS, Sosnowski K, Shumaker A, Yoon JY. Interfacial Effect-Based Quantification of Droplet Isothermal Nucleic Acid Amplification for Bacterial Infection. Sci Rep 2019; 9:9629. [PMID: 31270374 PMCID: PMC6610113 DOI: 10.1038/s41598-019-46028-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2019] [Accepted: 06/17/2019] [Indexed: 02/08/2023] Open
Abstract
Bacterial infection is a widespread problem in humans that can potentially lead to hospitalization and morbidity. The largest obstacle for physicians/clinicians is the time delay in accurately identifying infectious bacteria, especially their sub-species, in order to adequately treat and diagnose such infected patients. Loop-mediated amplification (LAMP) is a nucleic acid amplification method that has been widely used in diagnostic applications due to its simplicity of constant temperature, use of up to 4 to 6 primers (rendering it highly specific), and capability of amplifying low copies of target sequences. Use of interfacial effect-based monitoring is expected to dramatically shorten the time-to-results of nucleic acid amplification techniques. In this work, we developed a LAMP-based point-of-care platform for detection of bacterial infection, utilizing smartphone measurement of contact angle from oil-immersed droplet LAMP reactions. Whole bacteria (Escherichia coli O157:H7) were assayed in buffer as well as 5% diluted human whole blood. Monitoring of droplet LAMP reactions was demonstrated in a three-compartment, isothermal proportional-integrated-derived (PID)-controlled chip. Smartphone-captured images of droplet LAMP reactions, and their contact angles, were evaluated. Contact angle decreased substantially upon target amplification in both buffer and whole blood samples. In comparison, no-target control (NTC) droplets remained stable throughout the 30 min isothermal reactions. These results were explained by the pre-adsorption of plasma proteins to an oil-water interface (lowering contact angle), followed by time-dependent amplicon formation and their preferential adsorption to the plasma protein-occupied oil-water interface. Time-to-results was as fast as 5 min, allowing physicians to quickly make their decision for infected patients. The developed assay demonstrated quantification of bacteria concentration, with a limit-of-detection at 102 CFU/μL for buffer samples, and binary target or no-target identification with a limit-of-detection at 10 CFU/μL for 5% diluted whole blood samples.
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Affiliation(s)
- Tiffany-Heather Ulep
- Department of Biomedical Engineering, The University of Arizona, Tucson, Arizona, 85721, United States
| | - Alexander S Day
- Department of Biomedical Engineering, The University of Arizona, Tucson, Arizona, 85721, United States
| | - Katelyn Sosnowski
- Department of Biomedical Engineering, The University of Arizona, Tucson, Arizona, 85721, United States
| | - Alexa Shumaker
- Department of Biomedical Engineering, The University of Arizona, Tucson, Arizona, 85721, United States
| | - Jeong-Yeol Yoon
- Department of Biomedical Engineering, The University of Arizona, Tucson, Arizona, 85721, United States.
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2
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Tong R, Zhang L, Hu C, Chen X, Song Q, Lou K, Tang X, Chen Y, Gong X, Gao Y, Wen W. An Automated and Miniaturized Rotating-Disk Device for Rapid Nucleic Acid Extraction. MICROMACHINES 2019; 10:E204. [PMID: 30909465 PMCID: PMC6471407 DOI: 10.3390/mi10030204] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/07/2019] [Revised: 03/08/2019] [Accepted: 03/20/2019] [Indexed: 11/20/2022]
Abstract
The result of molecular diagnostic and detection greatly dependent on the quality and integrity of the isolated nucleic acid. In this work, we developed an automated miniaturized nucleic acid extraction device based on magnetic beads method, consisting of four components including a sample processing disc and its associated rotary power output mechanism, a pipetting module, a magnet module and an external central controller to enable a customizable and automated robust nucleic acid sample preparation. The extracted nucleic acid using 293T cells were verified using real-time polymerase chain reaction (PCR) and the data implies a comparable efficiency to a manual process, with the advantages of performing a flexible, time-saving (~10 min), and simple nucleic acid sample preparation.
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Affiliation(s)
- Rui Tong
- The Nano Science and Technology (NSNT) Program, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong.
| | - Lijuan Zhang
- Shenzhen Shineway Hi-Tech Co., Ltd., Shenzhen 518112, China.
| | - Chuandeng Hu
- Department of Physics, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong.
| | - Xuee Chen
- The Nano Science and Technology (NSNT) Program, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong.
| | - Qi Song
- Guangzhou HKUST Fok Ying Tung Research Institute, Nansha, Guangzhou 511458, China.
| | - Kai Lou
- Shenzhen Shineway Hi-Tech Co., Ltd., Shenzhen 518112, China.
| | - Xin Tang
- Guangzhou HKUST Fok Ying Tung Research Institute, Nansha, Guangzhou 511458, China.
| | - Yongsheng Chen
- Department of Ocean Science, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong.
| | - Xiuqing Gong
- Materials Genome Institute, University of Shanghai, Shanghai 200444, China.
| | - Yibo Gao
- Shenzhen Shineway Hi-Tech Co., Ltd., Shenzhen 518112, China.
| | - Weijia Wen
- Department of Physics, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong.
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Rodríguez-Ruiz I, Babenko V, Martínez-Rodríguez S, Gavira JA. Protein separation under a microfluidic regime. Analyst 2017; 143:606-619. [PMID: 29214270 DOI: 10.1039/c7an01568b] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Lab-on-a-Chip (LoC), or micro-Total Analysis Systems (μTAS), is recognized as a powerful analytical technology with high capabilities, though end-user products for protein purification are still far from being available on the market. Remarkable progress has been achieved in the separation of nucleic acids and proteins using electrophoretic microfluidic devices, while pintsize devices have been developed for protein isolation according to miniaturized chromatography principles (size, charge, affinity, etc.). In this work, we review the latest advances in the fabrication of components, detection methods and commercial implementation for the separation of biological macromolecules based on microfluidic systems, with some critical remarks on the perspectives of their future development towards standardized microfluidic systems and protocols. An outlook on the current needs and future applications is also presented.
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Affiliation(s)
| | - V Babenko
- Laboratorio de Estudios Cristalograficos, Instituto Andaluz de Ciencias de la Tierra, CSIC-University of Granada, Avenida de las Palmeras 4, 18100 Armilla, Granada, Spain.
| | - S Martínez-Rodríguez
- Department of Biochemistry and Molecular Biology III and Immunology. University of Granada, Granada, Spain
| | - J A Gavira
- Laboratorio de Estudios Cristalograficos, Instituto Andaluz de Ciencias de la Tierra, CSIC-University of Granada, Avenida de las Palmeras 4, 18100 Armilla, Granada, Spain.
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4
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HUANG S, HE YQ, JIAO F. Advances of Particles/Cells Magnetic Manipulation in Microfluidic Chips. CHINESE JOURNAL OF ANALYTICAL CHEMISTRY 2017. [DOI: 10.1016/s1872-2040(17)61033-8] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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5
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Lee M, Lopez-Martinez MJ, Baraket A, Zine N, Esteve J, Plaza JA, Ahmed N, Elaissari A, Jaffrezic-Renault N, Errachid A. Combination of PDMS microfilters and micromixers based on flexible thermoplastic films for size sorting and mixing of microparticles. J Appl Polym Sci 2015. [DOI: 10.1002/app.42088] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Michael Lee
- Institut de Sciences Analytiques (ISA); Université de Lyon; UMR 5280, 5 rue de la Doua 69100 Villeurbanne France
| | - Maria J. Lopez-Martinez
- Instituto de Microelectronica de Barcelona, IMB-CNM (CSIC); Campus UAB 08193 Bellaterra Barcelona Spain
| | - Abdoullatif Baraket
- Institut de Sciences Analytiques (ISA); Université de Lyon; UMR 5280, 5 rue de la Doua 69100 Villeurbanne France
| | - Nadia Zine
- Institut de Sciences Analytiques (ISA); Université de Lyon; UMR 5280, 5 rue de la Doua 69100 Villeurbanne France
| | - Jaume Esteve
- Instituto de Microelectronica de Barcelona, IMB-CNM (CSIC); Campus UAB 08193 Bellaterra Barcelona Spain
| | - Jose A. Plaza
- Instituto de Microelectronica de Barcelona, IMB-CNM (CSIC); Campus UAB 08193 Bellaterra Barcelona Spain
| | - Naveed Ahmed
- Laboratoire d'Automatique et de Génie des Procédés (LAGEP); Université de Lyon; UMR 5007, 43 boulevard du 11 novembre 1918 69622 Villeurbanne France
| | - Abdelhamid Elaissari
- Laboratoire d'Automatique et de Génie des Procédés (LAGEP); Université de Lyon; UMR 5007, 43 boulevard du 11 novembre 1918 69622 Villeurbanne France
| | - Nicole Jaffrezic-Renault
- Institut de Sciences Analytiques (ISA); Université de Lyon; UMR 5280, 5 rue de la Doua 69100 Villeurbanne France
| | - Abdelhamid Errachid
- Institut de Sciences Analytiques (ISA); Université de Lyon; UMR 5280, 5 rue de la Doua 69100 Villeurbanne France
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6
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Integration of sample pretreatment, μPCR, and detection for a total genetic analysis microsystem. Mikrochim Acta 2013. [DOI: 10.1007/s00604-013-1128-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
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Alvankarian J, Bahadorimehr A, Yeop Majlis B. A pillar-based microfilter for isolation of white blood cells on elastomeric substrate. BIOMICROFLUIDICS 2013; 7:14102. [PMID: 24403994 PMCID: PMC3555971 DOI: 10.1063/1.4774068] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/05/2012] [Accepted: 12/17/2012] [Indexed: 05/12/2023]
Abstract
Our goal is to design, fabricate, and characterize a pillar-based microfluidic device for size-based separation of human blood cells on an elastomeric substrate with application in the low-cost rapid prototyping of lab-chip devices. The single inlet single outlet device is using parallel U-shape arrays of pillars with cutoff size of 5.5 μm for trapping white blood cells (WBCs) in a pillar chamber with internal dead-volume of less than 1.0 μl. The microstructures are designed to limit the elastomeric deformation against fluid pressures. Numerical analysis showed that at maximum pressure loss of 15 kPa which is lower than the device conformal bonding strength, the pillar elastomeric deformation is less than 5% for flow rates of up to 1.0 ml min(-1). Molding technique was employed for device prototyping using polyurethane methacrylate (PUMA) resin and polydimethylsiloxane (PDMS) mold. Characterization of the dual-layer device with beads and blood samples is performed. Tests with blood injection showed that ∼18%-25% of WBCs are trapped and ∼84%-89% of red blood cells (RBCs) are passed at flow rates of 15-50 μl min(-1) with a slight decrease of WBCs trap and improve of the RBCs pass at higher flow rates. Similar results were obtained by separation of mixed microspheres of different size injected at flow rates of up to 400 μl min(-1). Tests with blood samples stained by fluorescent gel demonstrated that the WBCs are accumulated in the arrays of pillars that later end up to blockage of the device. Filtration results of using elastomeric substrate present a good consistency with the trend of separation efficiencies of the similar silicon-based filters.
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Affiliation(s)
- Jafar Alvankarian
- Institute of Microengineering and Nanoelectronics, Universiti Kebangsaan Malaysia, 43600 Bangi, Selangor, Malaysia
| | - Alireza Bahadorimehr
- Institute of Microengineering and Nanoelectronics, Universiti Kebangsaan Malaysia, 43600 Bangi, Selangor, Malaysia
| | - Burhanuddin Yeop Majlis
- Institute of Microengineering and Nanoelectronics, Universiti Kebangsaan Malaysia, 43600 Bangi, Selangor, Malaysia
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Menegatti E, Berardi D, Messina M, Ferrante I, Giachino O, Spagnolo B, Restagno G, Cognolato L, Roccatello D. Lab-on-a-chip: emerging analytical platforms for immune-mediated diseases. Autoimmun Rev 2012; 12:814-20. [PMID: 23219952 DOI: 10.1016/j.autrev.2012.11.005] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Miniaturization of analytical procedures has a significant impact on diagnostic testing since it provides several advantages such as: reduced sample and reagent consumption, shorter analysis time and less sample handling. Lab-on-a-chip (LoC), usually silicon, glass, or silicon-glass, or polymer disposable cartridges, which are produced using techniques inherited from the microelectronics industry, could perform and integrate the operations needed to carry out biochemical analysis through the mechanical realization of a dedicated instrument. Analytical devices based on miniaturized platforms like LoC may provide an important contribution to the diagnosis of high prevalence and rare diseases. In this paper we review some of the uses of Lab-on-a-chip in the clinical diagnostics of immune-mediated diseases and we provide an overview of how specific applications of these technologies could improve and simplify several complex diagnostic procedures.
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Affiliation(s)
- Elisa Menegatti
- Department of Medicine and Experimental Oncology, Section of Clinical Pathology, University of Turin, Turin, Italy.
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10
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Polymer-Based Microfluidic Devices for Pharmacy, Biology and Tissue Engineering. Polymers (Basel) 2012. [DOI: 10.3390/polym4031349] [Citation(s) in RCA: 103] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
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11
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Surfactant addition and alternating current electrophoretic oscillation during size fractionation of nanoparticles in channels with two or three different height segments. J Chromatogr A 2011; 1218:9102-10. [PMID: 22055518 DOI: 10.1016/j.chroma.2011.10.005] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2011] [Revised: 10/01/2011] [Accepted: 10/03/2011] [Indexed: 11/21/2022]
Abstract
An array of parallel planar nanochannels containing two or three segments with varying inner heights was fabricated and used for size fractionation of inorganic and biological nanoparticles. A liquid suspension of the particles was simply drawn through the nanochannels via capillary action. Using fluorescently labeled 30 nm polyacrylonitrile beads, different trapping behaviors were compared using nanochannels with 200-45 nm and 208-54-30 nm height segments. Addition of sodium dodecyl sulfate (SDS) surfactant to the liquid suspension and application of an AC electric field were shown to aid in the prevention of channel clogging. After initial particle trapping at the segment interfaces, significant particle redistribution occurred when applying a sinusoidal 8V peak-to-peak oscillating voltage with a frequency of 150 Hz and DC offset of 4V. Using the 208-54-30 nm channels, 30 nm hepatitis B virus (HBV) capsids were divided into three fractions. When the AC electric field was applied to this trapped sample, all of the virus particles passed through the interfaces and accumulated at the channel ends.
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12
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Jain A, Munn LL. Biomimetic postcapillary expansions for enhancing rare blood cell separation on a microfluidic chip. LAB ON A CHIP 2011; 11:2941-7. [PMID: 21773633 PMCID: PMC3743538 DOI: 10.1039/c1lc20401g] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
Blood cells naturally auto-segregate in postcapillary venules, with the erythrocytes (red blood cells, RBCs) aggregating near the axis of flow and the nucleated cells (NCs)--which include leukocytes, progenitor cells and, in cancer patients, circulating tumor cells--marginating toward the vessel wall. We have used this principle to design a microfluidic device that extracts nucleated cells (NCs) from whole blood. Fabricated using polydimethylsiloxane (PDMS) soft lithography, the biomimetic cell extraction device consists of rectangular microchannels that are 20-400 μm wide, 11 μm deep and up to 2 cm long. The key design feature is the use of repeated expansions/contractions of triangular geometry mimicking postcapillary venules, which enhance margination and optimize the extraction. The device operates on unprocessed whole blood and is able to extract 94 ± 4.5% of NCs with 45.75 ± 2.5-fold enrichment in concentration at a rate of 5 nl s(-1). The device eliminates the need to preprocess blood via centrifugation or RBC lysis, and is ready to be implemented as the initial stage of lab-on-a-chip devices that require enriched nucleated cells. The potential downstream applications are numerous, encompassing all preclinical and clinical assays that operate on enriched NC populations and include on-chip flow cytometry (A. Y. Fu et al., Anal. Chem., 2002, 74, 2451-2457; A. Y. Fu et al., Nat. Biotechnol., 1999, 17, 1109-1111), genetic analyses (M. M. Wang et al., Nat. Biotechnol., 2005, 23, 83-87; L. C. Waters et al., Anal. Chem., 1998, 70, 5172-5176) and circulating tumor cell extraction (S. Nagrath et al., Nature, 2007, 450, 1235-1241; S. L. Stott et al., Proc. Natl. Acad. Sci. U. S. A., 2010, 18392-18397; H. K. Lin et al., Clin. Cancer Res., 2010, 16, 5011-5018).
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Affiliation(s)
- Abhishek Jain
- Department of Biomedical Engineering, Boston University, 44 Cummington Street, Boston, 02119, USA. . harvard.edu; Tel: +1 617 726-4089
- Steele Lab for Tumor Biology, Massachusetts General Hospital and Harvard Medical School, 149 13th Street, Charlestown, MA 02129. ; Fax: +1 617 726 1962; Tel: +1 617 726-4085
| | - Lance L. Munn
- Steele Lab for Tumor Biology, Massachusetts General Hospital and Harvard Medical School, 149 13th Street, Charlestown, MA 02129. ; Fax: +1 617 726 1962; Tel: +1 617 726-4085
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13
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Sun T, Pawlowski S, Johnson ME. Highly efficient microscale purification of glycerophospholipids by microfluidic cell lysis and lipid extraction for lipidomics profiling. Anal Chem 2011; 83:6628-34. [PMID: 21766805 PMCID: PMC3165141 DOI: 10.1021/ac2011763] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
This article presents a novel method for small-scale lipidomics of bacterial cells by integrating extraction of glycerophospholipids on a microchip with a nanoelectrospray ionization quadrupole time-of-flight tandem mass spectrometer (nanoESI-Q-TOF MS/MS). The standard starting point for typical macroscale lipid analysis is a multiphase liquid-liquid extraction. Working with small populations of cells (1 to about 1000) requires a scaled down process in order to minimize dilution and facilitate the interface with microscale separation methods for sample cleanup and introduction to mass spectrometry. We have developed a microfluidic system that allows for lysis of bacterial cells, capture of lipids, and elution of captured lipids from a solid phase for microscale purification of lipids. The best on-chip extraction efficiency for glycerophospholipids was as high as 83.3% by integrating silica beads as the packing material with methanol as the eluent. A total of 10 successive measurements were evaluated indicating that the microchip packed with fresh silica beads is capable of being reused four times without any loss in the lipid extraction process. The initial screening based on high-resolution tandem mass spectrometry data along with a discovery profiling approach revealed the presence of 173 identified phospholipid species from microfluidic cell extracts. This work demonstrates the potential of incorporating microchip-based lipid extraction into cellular lipidomics research.
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Affiliation(s)
- Tao Sun
- Department of Chemistry and Biochemistry, Duquesne University, Pittsburgh, Pennsylvania 15282, USA.
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Park S, Zhang Y, Lin S, Wang TH, Yang S. Advances in microfluidic PCR for point-of-care infectious disease diagnostics. Biotechnol Adv 2011; 29:830-9. [PMID: 21741465 DOI: 10.1016/j.biotechadv.2011.06.017] [Citation(s) in RCA: 218] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2011] [Revised: 05/14/2011] [Accepted: 06/22/2011] [Indexed: 12/20/2022]
Abstract
Global burdens from existing or emerging infectious diseases emphasize the need for point-of-care (POC) diagnostics to enhance timely recognition and intervention. Molecular approaches based on PCR methods have made significant inroads by improving detection time and accuracy but are still largely hampered by resource-intensive processing in centralized laboratories, thereby precluding their routine bedside- or field-use. Microfluidic technologies have enabled miniaturization of PCR processes onto a chip device with potential benefits including speed, cost, portability, throughput, and automation. In this review, we provide an overview of recent advances in microfluidic PCR technologies and discuss practical issues and perspectives related to implementing them into infectious disease diagnostics.
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Affiliation(s)
- Seungkyung Park
- Department of Emergency Medicine, Johns Hopkins University, Baltimore, MD 21205, USA
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Abstract
We have developed a microfluidic device capable of fully integrated sample preparation and gene analysis from crude biosamples such as whole blood. Our platform takes the advantage of the silica superparamagnetic particle based solid phase extraction to develop an all-in-one scheme that performs cell lysis, DNA binding, washing, elution and the PCR in the same reaction chamber. The device also employs a unique reagent loading scheme, allowing efficient preparation of multiple reactions via a single injection channel. In addition, PCR is performed in a droplet-in-oil manner, eliminating the need for chamber sealing. The combination of these design features greatly reduces the complexity in implementing fully integrated lab-on-a-chip systems for genetic detection, facilitating parallel analysis of multiple samples or genes on a single microchip. The capability of the device is demonstrated by performing DNA isolation from the human whole blood sample and analyzing the Rsf-1 gene using the TaqMan probe based gene specific PCR assays.
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Kim JA, Lee SH, Park H, Kim JH, Park TH. Microheater based on magnetic nanoparticle embedded PDMS. NANOTECHNOLOGY 2010; 21:165102. [PMID: 20351408 DOI: 10.1088/0957-4484/21/16/165102] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
A microheater was established by embedding magnetic nanoparticles into PDMS (MNP-PDMS). MNP-PDMS generated heat under an AC magnetic field and the temperature was controlled by varying the magnetic particle content and the magnetic field intensity. In this study, the MNP-PDMS chip was demonstrated to amplify the target DNA (732 bp) with > 90% efficiency compared to the conventional PCR thermocycler, and exhibited good performance in regards to temperature control. This system holds great promise for reliably controlling the temperature of thermal processes on an integrated microchip platform for biochemical applications.
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Affiliation(s)
- Jeong Ah Kim
- School of Chemical and Biological Engineering, Seoul National University, Seoul 151-744, Korea
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17
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Zhang C, Xing D. Single-Molecule DNA Amplification and Analysis Using Microfluidics. Chem Rev 2010; 110:4910-47. [DOI: 10.1021/cr900081z] [Citation(s) in RCA: 115] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- Chunsun Zhang
- MOE Key Laboratory of Laser Life Science & Institute of Laser Life Science, College of Biophotonics, South China Normal University, Guangzhou 510631, China
| | - Da Xing
- MOE Key Laboratory of Laser Life Science & Institute of Laser Life Science, College of Biophotonics, South China Normal University, Guangzhou 510631, China
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18
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Lien KY, Lee GB. Miniaturization of molecular biological techniques for gene assay. Analyst 2010; 135:1499-518. [PMID: 20390199 DOI: 10.1039/c000037j] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
The rapid diagnosis of various diseases is a critical advantage of many emerging biomedical tools. Due to advances in preventive medicine, tools for the accurate analysis of genetic mutation and associated hereditary diseases have attracted significant interests in recent years. The entire diagnostic process usually involves two critical steps, namely, sample pre-treatment and genetic analysis. The sample pre-treatment processes such as extraction and purification of the target nucleic acids prior to genetic analysis are essential in molecular diagnostics. The genetic analysis process may require specialized apparatus for nucleic acid amplification, sequencing and detection. Traditionally, pre-treatment of clinical biological samples (e.g. the extraction of deoxyribonucleic acid (DNA) or ribonucleic acid (RNA)) and the analysis of genetic polymorphisms associated with genetic diseases are typically a lengthy and costly process. These labor-intensive and time-consuming processes usually result in a high-cost per diagnosis and hinder their practical applications. Besides, the accuracy of the diagnosis may be affected owing to potential contamination from manual processing. Alternatively, due to significant advances in micro-electro-mechanical-systems (MEMS) and microfluidic technology, there are numerous miniature systems employed in biomedical applications, especially for the rapid diagnosis of genetic diseases. A number of advantages including automation, compactness, disposability, portability, lower cost, shorter diagnosis time, lower sample and reagent consumption, and lower power consumption can be realized by using these microfluidic-based platforms. As a result, microfluidic-based systems are becoming promising platforms for genetic analysis, molecular biology and for the rapid detection of genetic diseases. In this review paper, microfluidic-based platforms capable of identifying genetic sequences and diagnosis of genetic mutations are surveyed and reviewed. Some critical issues with the use of microfluidic-based systems for diagnosis of genetic diseases are also highlighted.
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Affiliation(s)
- Kang-Yi Lien
- Institute of Nanotechnology and Microsystems Engineering, National Cheng Kung University, Tainan, 701, Taiwan
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19
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An integrated microfluidic device for DNA purification and PCR amplification of STR fragments. Forensic Sci Int Genet 2010; 4:178-86. [DOI: 10.1016/j.fsigen.2009.02.010] [Citation(s) in RCA: 72] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2008] [Revised: 01/15/2009] [Accepted: 02/01/2009] [Indexed: 01/20/2023]
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20
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Huang CT, Li PN, Pai CY, Leu TS, Jen CP. Design and Simulation of a Microfluidic Blood-Plasma Separation Chip Using Microchannel Structures. SEP SCI TECHNOL 2010. [DOI: 10.1080/01496390903402125] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Affiliation(s)
- Ching-Te Huang
- a Department of Mechanical Engineering , National Chung Cheng University , Chia-Yi, Taiwan, R.O.C
| | - Po-Ni Li
- a Department of Mechanical Engineering , National Chung Cheng University , Chia-Yi, Taiwan, R.O.C
| | - Ching-Yi Pai
- b Department of Aeronautics and Astronautics , National Cheng Kung University , Tainan, Taiwan, R.O.C
| | - Tzong-Shyng Leu
- b Department of Aeronautics and Astronautics , National Cheng Kung University , Tainan, Taiwan, R.O.C
| | - Chun-Ping Jen
- a Department of Mechanical Engineering , National Chung Cheng University , Chia-Yi, Taiwan, R.O.C
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Han KH, Han SI, Frazier AB. Lateral displacement as a function of particle size using a piecewise curved planar interdigitated electrode array. LAB ON A CHIP 2009; 9:2958-64. [PMID: 19789750 DOI: 10.1039/b909753h] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
We describe the lateral displacement of a particle passing over a planar interdigitated electrode array at an angle as a function of the particle size. The lateral displacement was also measured as a function of the angle between the electrode and the direction of flow. A simplified line charge model was used for numerically estimating the lateral displacement of fluorescent polystyrene (PS) beads with three different diameters. Using the lateral displacement as a function of particle size, we developed a lateral dielectrophoretic (DEP) microseparator, which enables continuous discrimination of particles by size. The microchannel was divided into three regions, each with an electrode array placed at a different angle with respect to the direction of flow. The experiment using an admixture of 3-, 5-, and 10-microm PS beads showed that the lateral DEP microseparator could continuously separate out 99.86% of the 3-microm beads, 98.82% of the 5-microm beads, and 99.69% of the 10-microm beads, simply by using a 200-kHz 12-Vp-p AC voltage to create the lateral DEP force. The lateral DEP microseparator is thus a practical device for simultaneously separating particles according to size from a heterogeneous admixture.
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Affiliation(s)
- Ki-Ho Han
- School of Nano Engineering, Inje University, Obang-dong, Gimhae, GyongNam, 621-749, Republic of Korea.
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22
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Chung CK, Chang HC, Shih TR, Lin SL, Hsiao EJ, Chen YS, Chang EC, Chen CC, Lin CC. Water-assisted CO2 laser ablated glass and modified thermal bonding for capillary-driven bio-fluidic application. Biomed Microdevices 2009; 12:107-14. [DOI: 10.1007/s10544-009-9365-x] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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23
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Immunomagnetic bead-based cell concentration microdevice for dilute pathogen detection. Biomed Microdevices 2009; 10:909. [PMID: 18677651 DOI: 10.1007/s10544-008-9206-3] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
A cell concentration microdevice for immunomagnetic pathogen isolation from a dilute sample is presented. Cells are driven by integrated on-chip pumps through a fluidized bed of immobilized immunomagnetic beads. Off-chip polymerase chain reaction and capillary electrophoretic analysis are used to determine capture efficiencies of E. coli and to optimize the system. Beads are immobilized after each split in a bifurcated channel system to ensure a balanced distribution of beads in all the capture channels. The addition of a pumping flutter step to repeatedly drive sample through the bead bed was found to enhance capture. Capture efficiencies of 70% and a limit of detection of 2 cfu/microL were achieved; specific capture of E. coli at a concentration of 100 cfu/microL in a 100-fold background of S. aureus is shown. This capture/concentration system is an important step in overcoming the macro-to-micro interface challenge in the development of microdevices for pathogen detection.
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24
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Law WS, Li SFY, Kricka LJ. Detection of enteropathogenic Escherichia coli by microchip capillary electrophoresis. Methods Mol Biol 2009; 509:169-179. [PMID: 19212722 DOI: 10.1007/978-1-59745-372-1_12] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
There is always a need to detect the presence of microorganisms, either as contaminants in food and pharmaceutical industries or bioindicators for disease diagnosis. Hence, it is important to develop efficient, rapid, and simple methods to detect microorganisms. Traditional culturing method is unsatisfactory due to its long incubation time. Molecular methods, although capable of providing a high degree of specificity, are not always useful in providing quick tests of presence or absence of microorganisms. Microchip elec-trophoresis has been recently employed to address problems associated with the detection of microorganisms due to its high versatility, selectivity, sensitivity, and short analysis times. In this work, the potential of PDMS-based microchip electrophoresis in the identification and characterization of microorganism was evaluated. Enteropathogenic E. coli (EPEC) was selected as the model microorganism. To obtain repeat-able separations, sample pretreatment was found to be essential. Microchip electrophoresis with laser-induced fluorescence detection could potentially revolutionize certain aspects of microbiology involving diagnosis, profiling of pathogens, environmental analysis, and many others areas of study.
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Affiliation(s)
- Wai S Law
- Department of Chemistry, National University of Singapore, Singapore, Republic of Singapore
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25
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Hsiung LC, Yang CH, Chiu CL, Chen CL, Wang Y, Lee H, Cheng JY, Ho MC, Wo AM. A planar interdigitated ring electrode array via dielectrophoresis for uniform patterning of cells. Biosens Bioelectron 2008; 24:875-81. [DOI: 10.1016/j.bios.2008.07.027] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2008] [Revised: 06/27/2008] [Accepted: 07/09/2008] [Indexed: 10/21/2022]
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26
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Hwang KY, Lim HK, Jung SY, Namkoong K, Kim JH, Huh N, Ko C, Park JC. Bacterial DNA Sample Preparation from Whole Blood Using Surface-Modified Si Pillar Arrays. Anal Chem 2008; 80:7786-91. [DOI: 10.1021/ac8012048] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Kyu-Youn Hwang
- Bio & Health Lab., Samsung Advanced Institute of Technology (SAIT), Mt. 14-1, Nongseo-Dong, Giheung-Gu, Yongin-Si, Gyeonggi-Do, South Korea, 449-712
| | - Hee-Kyun Lim
- Bio & Health Lab., Samsung Advanced Institute of Technology (SAIT), Mt. 14-1, Nongseo-Dong, Giheung-Gu, Yongin-Si, Gyeonggi-Do, South Korea, 449-712
| | - Seong-Young Jung
- Bio & Health Lab., Samsung Advanced Institute of Technology (SAIT), Mt. 14-1, Nongseo-Dong, Giheung-Gu, Yongin-Si, Gyeonggi-Do, South Korea, 449-712
| | - Kak Namkoong
- Bio & Health Lab., Samsung Advanced Institute of Technology (SAIT), Mt. 14-1, Nongseo-Dong, Giheung-Gu, Yongin-Si, Gyeonggi-Do, South Korea, 449-712
| | - Joon-Ho Kim
- Bio & Health Lab., Samsung Advanced Institute of Technology (SAIT), Mt. 14-1, Nongseo-Dong, Giheung-Gu, Yongin-Si, Gyeonggi-Do, South Korea, 449-712
| | - Nam Huh
- Bio & Health Lab., Samsung Advanced Institute of Technology (SAIT), Mt. 14-1, Nongseo-Dong, Giheung-Gu, Yongin-Si, Gyeonggi-Do, South Korea, 449-712
| | - Christopher Ko
- Bio & Health Lab., Samsung Advanced Institute of Technology (SAIT), Mt. 14-1, Nongseo-Dong, Giheung-Gu, Yongin-Si, Gyeonggi-Do, South Korea, 449-712
| | - Jae-Chan Park
- Bio & Health Lab., Samsung Advanced Institute of Technology (SAIT), Mt. 14-1, Nongseo-Dong, Giheung-Gu, Yongin-Si, Gyeonggi-Do, South Korea, 449-712
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27
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Yuen PK. SmartBuild-a truly plug-n-play modular microfluidic system. LAB ON A CHIP 2008; 8:1374-8. [PMID: 18651081 DOI: 10.1039/b805086d] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
In this Technical Note, for the first time, a truly "plug-n-play" modular microfluidic system (SmartBuild Plug-n-Play Modular Microfluidic System) is presented for designing and building integrated modular microfluidic systems for biological and chemical applications. The modular microfluidic system can be built by connecting multiple microfluidic components together to form a larger integrated system. The SmartBuild System comprises of a motherboard with interconnect channels/grooves, fitting components, microchannel inserts with different configurations and microchips/modules with different functionalities. Also, heaters, micropumps and valving systems can be designed and used in the system. Examples of an integrated mixing system and reaction systems are presented here to demonstrate the versatility of the SmartBuild System.
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Affiliation(s)
- Po Ki Yuen
- Science and Technology, Corning Incorporated, Corning, New York, 14831-0001, USA.
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28
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Hu JE, Erickson JS, Taitt CR, Lin B, Ligler AG, Blaney KM, Malanoski AP, Ligler FS. A Parametric Study of Sample Lysis and DNA Purification Techniques for Use in Automated Devices. ANAL LETT 2008. [DOI: 10.1080/00032710802162186] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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29
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Wang F, Yang M, Burns MA. Microfabricated valveless devices for thermal bioreactions based on diffusion-limited evaporation. LAB ON A CHIP 2008; 8:88-97. [PMID: 18094766 PMCID: PMC2752386 DOI: 10.1039/b711770a] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Microfluidic devices that reduce evaporative loss during thermal bioreactions such as PCR without microvalves have been developed by relying on the principle of diffusion-limited evaporation. Both theoretical and experimental results demonstrate that the sample evaporative loss can be reduced by more than 20 times using long narrow diffusion channels on both sides of the reaction region. In order to further suppress the evaporation, the driving force for liquid evaporation is reduced by two additional techniques: decreasing the interfacial temperature using thermal isolation and reducing the vapor concentration gradient by replenishing water vapor in the diffusion channels. Both thermal isolation and vapor replenishment techniques can limit the sample evaporative loss to approximately 1% of the reaction content.
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Affiliation(s)
- Fang Wang
- Department of Chemical Engineering, University of Michigan, Ann Arbor, MI 48109
| | - Ming Yang
- Department of Chemical Engineering, University of Michigan, Ann Arbor, MI 48109
| | - Mark A. Burns
- Department of Chemical Engineering, University of Michigan, Ann Arbor, MI 48109
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI 48109
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30
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Nevill JT, Cooper R, Dueck M, Breslauer DN, Lee LP. Integrated microfluidic cell culture and lysis on a chip. LAB ON A CHIP 2007; 7:1689-95. [PMID: 18030388 DOI: 10.1039/b711874k] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
We present an integrated microfluidic cell culture and lysis platform for automated cell analysis that improves on systems which require multiple reagents and manual procedures. Through the combination of previous technologies developed in our lab (namely, on-chip cell culture and electrochemical cell lysis) we have designed, fabricated, and characterized an integrated microfluidic platform capable of culturing HeLa, MCF-7, Jurkat, and CHO-K1 cells for up to five days and subsequently lysing the cells without the need to add lysing reagents. On-demand lysis was accomplished by local hydroxide ion generation within microfluidic chambers, releasing both proteinacious (GFP) and genetic (Hoescht-stained DNA) material. Sample proteins exposed to the electrochemical lysis conditions were immunodetectable (p53) and their enzymatic activity (HRP) was investigated.
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Affiliation(s)
- J Tanner Nevill
- Biomolecular Nanotechnology Center, Berkeley Sensor & Actuator Center, Department of Bioengineering, University of California, UCSF/UCB Joint Graduate Group in Bioengineering, Berkeley, CA, USA
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31
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Chen L, Manz A, Day PJR. Total nucleic acid analysis integrated on microfluidic devices. LAB ON A CHIP 2007; 7:1413-23. [PMID: 17960265 DOI: 10.1039/b708362a] [Citation(s) in RCA: 100] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
The design and integration of microfluidic devices for on-chip amplification of nucleic acids from various biological samples has undergone extensive development. The actual benefit to the biological community is far from clear, with a growing, but limited, number of application successes in terms of a full on-chip integrated analysis. Several advances have been made, particularly with the integration of amplification and detection, where amplification is most often the polymerase chain reaction. Full integration including sample preparation remains a major obstacle for achieving a quantitative analysis. We review the recently described devices incorporating in vitro gene amplification and compare devices relative to each other and in terms of fully achieving a miniaturised total analysis system (micro-TAS).
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Affiliation(s)
- Lin Chen
- Institute for Analytical Sciences, Bunsen-Kirchhoff Str. 11, D-44139 Dortmund, Germany
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32
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Grodzinski P, Liu R, Yang J, Ward MD. Microfluidic system integration in sample preparation chip-sets - a summary. CONFERENCE PROCEEDINGS : ... ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL CONFERENCE 2007; 2004:2615-8. [PMID: 17270811 DOI: 10.1109/iembs.2004.1403751] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
An increasing complexity of microfluidic chips and systems used for biochemical assay applications calls for the development of new strategies towards their functionality integration in order to achieve optimum assay performance. Approaches to an integration of microfluidic chips into diagnostic fluidic systems are reviewed with the emphasis on the selection of assay application, integration scheme, interfacing, and fabrication platform. In particular, we discuss a system containing polymer microfluidic chip-sets capable of cell pre-concentration from a complex sample matrix using immunomagnetic separations.
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Blattert C, Jurischka R, Tahhan I, Schoth A, Kerth P, Menz W. Separation of blood in microchannel bends. CONFERENCE PROCEEDINGS : ... ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL CONFERENCE 2007; 2004:2627-30. [PMID: 17270814 DOI: 10.1109/iembs.2004.1403754] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Most clinical chemistry tests are performed on cell-free serum or plasma. Therefore micro assay devices for blood tests require integrated on-chip microfluidics for separation of plasma or serum from blood. This is achieved by a new blood separation technique based on a microchannel bend structure developed within the collaborative microtele-biochip muTBC) project co-funded by the German Ministry for education and research (BMBF). Different prototype polymer chips have been manufactured with an UV-LIGA process and hot embossing technology. The separation efficiency of these chips has been determined with samples of human whole blood as well as diluted blood samples. The results show different separation efficiencies up to 90% for blood cells and plasma depending on microchannel geometry as well as cell concentration. As compared to present microfluidic devices for the separation of blood cells like filters or filtration by diffusion the microchannel bend is an integrated on-chip blood separation method, which combines the advantages of rapid separation times and a simple geometry.
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Affiliation(s)
- C Blattert
- Inst. fuer Mikrosystemtechnik, Freiburg Univ., Germany
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34
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Arifin DR, Yeo LY, Friend JR. Microfluidic blood plasma separation via bulk electrohydrodynamic flows. BIOMICROFLUIDICS 2007; 1:14103. [PMID: 19693352 PMCID: PMC2709949 DOI: 10.1063/1.2409629] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/09/2006] [Accepted: 11/21/2006] [Indexed: 05/02/2023]
Abstract
An effective mechanism for rapid and efficient microfluidic particle trapping and concentration is proposed without requiring any mechanically moving parts. When a voltage beyond the threshold atmospheric ionization value is applied on a sharp electrode tip mounted at an angle above a microfluidic liquid chamber, the bulk electrohydrodynamic air thrust that is generated results in interfacial shear and, hence, primary azimuthal liquid surface recirculation. This discharge driven vortex mechanism, in turn, causes a secondary bulk meridional liquid recirculation, which produces an inward radial force near the bottom of the chamber. Particles suspended in the liquid are then rapidly convected by the bulk recirculation toward the bottom, where the inward radial force causes them to spiral in a helical swirl-like fashion toward a stagnation point. In particular, we show that these flows, similar to Batchelor flows occurring in a cylindrical liquid column between a stationary and rotating disk, can be used for the separation of red blood cells from blood plasma in a miniaturized device.
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Affiliation(s)
- Dian R Arifin
- MicroNanophysics Research Laboratory, Department of Mechanical Engineering,Monash University, Clayton, VIC 3800, Australia
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35
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Liu RH, Lee AP. PCR in Integrated Microfluidic Systems. INTEGRATED BIOCHIPS FOR DNA ANALYSIS 2007. [PMCID: PMC7124038 DOI: 10.1007/978-0-387-76759-8_7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Miniaturized integrated DNA analysis systems offer the potential to provide unprecedented advances in cost and speed relative to current benchtop-scale instrumentation by allowing rapid bioanalysis assays to be performed in a portable self contained device format that can be inexpensively mass-produced. The polymerase chain reaction (PCR) has been a natural focus of many of these miniaturization efforts, owing to its capability to efficiently replicate target regions of interest from small quantities template DNA. Scale-down of PCR has proven to be particularly challenging, however, due to an unfavorable combination of relatively severe temperature extremes (resulting in the need to repeatedly heat minute aqueous sample volumes to temperatures in the vicinity of 95°C with minimal evaporation) and high surface area to volume conditions imposed by nanoliter reactor geometries (often leading to inhibition of the reaction by nonspecific adsorption of reagents at the reactor walls). Despite these daunting challenges, considerable progress has been made in the development of microfluidic devices capable of performing increasingly sophisticated PCR-based bioassays. This chapter reviews the progress that has been made to date and assesses the outlook for future advances.
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Affiliation(s)
- Robin Hui Liu
- Osmetech Molecular Diagnostics, Pasadena, California USA
| | - Abraham P. Lee
- University of California at Irvine, Irvine, California USA
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36
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Song H, Li HW, Munson MS, Van Ha TG, Ismagilov RF. On-chip titration of an anticoagulant argatroban and determination of the clotting time within whole blood or plasma using a plug-based microfluidic system. Anal Chem 2006; 78:4839-49. [PMID: 16841902 PMCID: PMC1851927 DOI: 10.1021/ac0601718] [Citation(s) in RCA: 116] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
This paper describes extending plug-based microfluidics to handling complex biological fluids such as blood, solving the problem of injecting additional reagents into plugs, and applying this system to measuring of clotting time in small volumes of whole blood and plasma. Plugs are droplets transported through microchannels by fluorocarbon fluids. A plug-based microfluidic system was developed to titrate an anticoagulant (argatroban) into blood samples and to measure the clotting time using the activated partial thromboplastin time (APTT) test. To carry out these experiments, the following techniques were developed for a plug-based system: (i) using Teflon AF coating on the microchannel wall to enable formation of plugs containing blood and transport of the solid fibrin clots within plugs, (ii) using a hydrophilic glass capillary to enable reliable merging of a reagent from an aqueous stream into plugs, (iii) using bright-field microscopy to detect the formation of a fibrin clot within plugs and using fluorescent microscopy to detect the production of thrombin using a fluorogenic substrate, and (iv) titration of argatroban (0-1.5 microg/mL) into plugs and measurement of the resulting APTTs at room temperature (23 degrees C) and physiological temperature (37 degrees C). APTT measurements were conducted with normal pooled plasma (platelet-poor plasma) and with donor's blood samples (both whole blood and platelet-rich plasma). APTT values and APTT ratios measured by the plug-based microfluidic device were compared to the results from a clinical laboratory at 37 degrees C. APTT obtained from the on-chip assay were about double those from the clinical laboratory but the APTT ratios from these two methods agreed well with each other.
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37
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Liu RH, Dill K, Fuji HS, McShea A. Integrated microfluidic biochips for DNA microarray analysis. Expert Rev Mol Diagn 2006; 6:253-61. [PMID: 16512784 DOI: 10.1586/14737159.6.2.253] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
A fully integrated and self-contained microfluidic biochip device has been developed to automate the fluidic handling steps required to perform a gene expression study of the human leukemia cell line (K-562). The device consists of a DNA microarray semiconductor chip with 12,000 features and a microfluidic cartridge that consists of microfluidic pumps, mixers, valves, fluid channels and reagent storage chambers. Microarray hybridization and subsequent fluidic handling and reactions (including a number of washing and labeling steps) were performed in this fully automated and miniature device before fluorescent image scanning of the microarray chip. Electrochemical micropumps were integrated in the cartridge to provide pumping of liquid solutions. A micromixing technique based on gas bubbling generated by electrochemical micropumps was developed. Low-cost check valves were implemented in the cartridge to prevent cross-talk of the stored reagents. A single-color transcriptional analysis of K-562 cells with a series of calibration controls (spiked-in controls) was performed to characterize this new platform with regard to sensitivity, specificity and dynamic range. The device detected sample RNAs with a concentration as low as 0.375 pM. Detection was quantitative over more than 3 orders of magnitude. Experiments also demonstrated that chip-to-chip variability was low, indicating that the integrated microfluidic devices eliminate manual fluidic handling steps that can be a significant source of variability in genomic analysis.
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38
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Thorslund S, Klett O, Nikolajeff F, Markides K, Bergquist J. A hybrid poly(dimethylsiloxane) microsystem for on-chip whole blood filtration optimized for steroid screening. Biomed Microdevices 2006; 8:73-9. [PMID: 16491334 DOI: 10.1007/s10544-006-6385-7] [Citation(s) in RCA: 80] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Miniaturized biochemical devices in glass, silicon and polymer materials are starting to find their way from the academic laboratories to real-life applications. However, most attention has been given to miniaturize the downstream functions of various microfluidic systems, leaving the sample introduction and preparation steps to more conventional, bulkier solutions. For point-of-care diagnostics in particular, it becomes crucial to be able to handle complex human samples in a miniaturized format.In this work, we report on a microsystem for on-chip sample preparation that is able to remove blood cells from whole blood. The hybrid system consists of a commercially available membrane filter incorporated into a poly(dimethylsiloxane) (PDMS) casted device. Membrane materials were evaluated on the bases of low nonspecific adsorption of free and protein-bound testosterone as analyte substance. The hybrid system including a hydrophilic polypropylene filter successfully removed blood cells from diluted human whole blood. Surface oxidation was sufficient to make the plasma filtrate flow through the membrane filter and the channel system by capillary force alone and thus no external pumping source was needed.
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Affiliation(s)
- Sara Thorslund
- Department of Engineering Sciences, Angström Laboratory, Uppsala University, Box 534, SE-751 21 Uppsala, Sweden
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39
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Consolandi C, Severgnini M, Frosini A, Caramenti G, De Fazio M, Ferrara F, Zocco A, Fischetti A, Palmieri M, De Bellis G. Polymerase chain reaction of 2-kb cyanobacterial gene and human anti-alpha1-chymotrypsin gene from genomic DNA on the In-Check single-use microfabricated silicon chip. Anal Biochem 2006; 353:191-7. [PMID: 16620755 DOI: 10.1016/j.ab.2006.03.019] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2006] [Revised: 03/06/2006] [Accepted: 03/09/2006] [Indexed: 11/25/2022]
Abstract
The microfabricated chip is a promising format for automating and miniaturizing the multiple steps of genotyping. We tested an innovative silicon biochip (In-Check Lab-on-Chip; STMicroelectronics, Agrate Brianza, Italy) designed for polymerase chain reaction (PCR) analysis of complex biological samples. The chip is mounted on a 1x3-in(2). plastic slide that provides the necessary mechanical, thermal, electrical, and fluidic connections. A temperature control system drives the chip to the desired temperatures, and a graphical user interface allows experimenters to define cycling conditions and monitor reactions in real time. During thermal cycling, we recorded a cooling rate of 3.2 degrees C/s and a heating rate of 11 degrees C/s. The temperature maintained at each thermal plateau was within 0.13 degrees C of the programmed temperature at three sensors. From 0.5 ng/microl genomic DNA, the In-Check device successfully amplified the 2060-bp cyanobacterial 16S rRNA gene and the 330-bp human anti-alpha(1)-chymotrypsin gene. The shortest PCR protocol that produced an amplicon by capillary electrophoresis comprised 30 cycles and was 22.5 min long. These thermal cycling characteristics suggest that the In-Check device will permit future development of a genotyping lab-on-a-chip device, yielding results in a short time from a limited amount of biological starting material.
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Affiliation(s)
- Clarissa Consolandi
- Institute of Biomedical Technologies, National Research Council, ITB-CNR, Via Fratelli Cervi 93, I-20090 Segrate, MI, Italy.
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40
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Lee TMH, Hsing IM. DNA-based bioanalytical microsystems for handheld device applications. Anal Chim Acta 2006; 556:26-37. [PMID: 17723328 PMCID: PMC7094345 DOI: 10.1016/j.aca.2005.05.075] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2005] [Revised: 05/23/2005] [Accepted: 05/25/2005] [Indexed: 11/29/2022]
Abstract
This article reviews and highlights the current development of DNA-based bioanalytical microsystems for point-of-care diagnostics and on-site monitoring of food and water. Recent progresses in the miniaturization of various biological processing steps for the sample preparation, DNA amplification (polymerase chain reaction), and product detection are delineated in detail. Product detection approaches utilizing "portable" detection signals and electrochemistry-based methods are emphasized in this work. The strategies and challenges for the integration of individual processing module on the same chip are discussed.
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Affiliation(s)
- Thomas Ming-Hung Lee
- Department of Chemical Engineering, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong
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41
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Kuhnline CD, Gangel MG, Hulvey MK, Martin RS. Detecting thiols in a microchip device using micromolded carbon ink electrodes modified with cobalt phthalocyanine. Analyst 2006; 131:202-7. [PMID: 16440083 DOI: 10.1039/b511153f] [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: 11/21/2022]
Abstract
This paper describes the fabrication and evaluation of a chemically modified carbon ink microelectrode to detect thiols of biological interest. The detection of thiols, such as homocysteine and cysteine, is necessary to monitor various disease states. The biological implications of these thiols generate the need for miniaturized detection systems that enable portable monitoring as well as quantitative results. In this work, we utilize a microchip device that incorporates a micromolded carbon ink electrode modified with cobalt phthalocyanine to detect thiols. Cobalt phthalocyanine (CoPC) is an electrocatalyst that lowers the potential needed for the oxidation of thiols. The CoPC/carbon ink composition was optimized for the micromolding method and the resulting microelectrode was characterized with microchip-based flow injection analysis. It was found that CoPC lowers the overpotential for thiols but, as compared to direct amperometric detection, a pulsed detection scheme was needed to constantly regenerate the electrocatalyst surface, leading to improved peak reproducibility and limits of detection. Using the pulsed method, cysteine exhibited a linear response between 10-250 microM (r(2) = 0.9991) with a limit of detection (S/N = 3) of 7.5 microM, while homocysteine exhibited a linear response between 10-500 microM (r(2) = 0.9967) with a limit of detection of 6.9 microM. Finally, to demonstrate the ability to measure thiols in a biological sample using a microchip device, the CoPC-modified microelectrode was utilized for the detection of cysteine in the presence of rabbit erythrocytes.
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Zhang L, Dang F, Kaji N, Baba Y. Fast extraction, amplification and analysis of genes from human blood. J Chromatogr A 2005; 1106:175-80. [PMID: 16337635 DOI: 10.1016/j.chroma.2005.10.071] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2005] [Revised: 10/21/2005] [Accepted: 10/27/2005] [Indexed: 11/30/2022]
Abstract
In order to shorten the time spent on the sample preparation for gene analysis, a novel method was proposed through the combination of fast DNA extraction and purification by Generation capture disk, amplification by capillary polymerase chain reaction, and confirmation of amplification products by microchip electrophoresis. With this method, 3 microL blood was enough to obtain adequate target fragments in human genes. Under the optimal conditions in each step, the sample preparation for eight fragments in beta-globin gene and four fragments in ras gene could be finished within 20 min. Since all the experiments were performed on commercial instruments, this method showed a wide range of applicability. In addition, other advantages such as fast speed and low consumption of samples were demonstrated. All these merits proved that such a combination method was of great potential for the clinical diagnostics.
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Affiliation(s)
- Lihua Zhang
- Department of Molecular and Pharmaceutical Biotechnology, Graduate School of Pharmaceutical Sciences, The University of Tokushima, CREST, Japan Science and Technology Corporation (JST), Tokushima 770-8505, Japan
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Zhang C, Xu J, Ma W, Zheng W. PCR microfluidic devices for DNA amplification. Biotechnol Adv 2005; 24:243-84. [PMID: 16326063 DOI: 10.1016/j.biotechadv.2005.10.002] [Citation(s) in RCA: 444] [Impact Index Per Article: 23.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2005] [Revised: 10/02/2005] [Accepted: 10/24/2005] [Indexed: 11/23/2022]
Abstract
The miniaturization of biological and chemical analytical devices by micro-electro-mechanical-systems (MEMS) technology has posed a vital influence on such fields as medical diagnostics, microbial detection and other bio-analysis. Among many miniaturized analytical devices, the polymerase chain reaction (PCR) microchip/microdevices are studied extensively, and thus great progress has been made on aspects of on-chip micromachining (fabrication, bonding and sealing), choice of substrate materials, surface chemistry and architecture of reaction vessel, handling of necessary sample fluid, controlling of three or two-step temperature thermocycling, detection of amplified nucleic acid products, integration with other analytical functional units such as sample preparation, capillary electrophoresis (CE), DNA microarray hybridization, etc. However, little has been done on the review of above-mentioned facets of the PCR microchips/microdevices including the two formats of flow-through and stationary chamber in spite of several earlier reviews [Zorbas, H. Miniature continuous-flow polymerase chain reaction: a breakthrough? Angew Chem Int Ed 1999; 38 (8):1055-1058; Krishnan, M., Namasivayam, V., Lin, R., Pal, R., Burns, M.A. Microfabricated reaction and separation systems. Curr Opin Biotechnol 2001; 12:92-98; Schneegabeta, I., Köhler, J.M. Flow-through polymerase chain reactions in chip themocyclers. Rev Mol Biotechnol 2001; 82:101-121; deMello, A.J. DNA amplification: does 'small' really mean 'efficient'? Lab Chip 2001; 1: 24N-29N; Mariella, Jr. R. MEMS for bio-assays. Biomed Microdevices 2002; 4 (2):77-87; deMello AJ. Microfluidics: DNA amplification moves on. Nature 2003; 422:28-29; Kricka, L.J., Wilding, P. Microchip PCR. Anal BioAnal Chem 2003; 377:820-825]. In this review, we survey the advances of the above aspects among the PCR microfluidic devices in detail. Finally, we also illuminate the potential and practical applications of PCR microfluidics to some fields such as microbial detection and disease diagnosis, based on the DNA/RNA templates used in PCR microfluidics. It is noted, especially, that this review is to help a novice in the field of on-chip PCR amplification to more easily find the original papers, because this review covers almost all of the papers related to on-chip PCR microfluidics.
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Affiliation(s)
- Chunsun Zhang
- Micro-Energy System Laboratory, Guangzhou Institute of Energy Conversion, The Chinese Academy of Sciences, No. 1 Nengyuan Road, Wushan, Tianhe District, Guangzhou 510640, PR China
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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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Ferrari M, Cremonesi L, Bonini P, Stenirri S, Foglieni B. Molecular diagnostics by microelectronic microchips. Expert Rev Mol Diagn 2005; 5:183-92. [PMID: 15833048 DOI: 10.1586/14737159.5.2.183] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Molecular diagnostics is being revolutionized by the development of highly advanced technologies for DNA and RNA testing. One of the most important challenges is the integration of microelectronics to microchip-based nucleic acid technologies. The specific characteristics of these microsystems make the miniaturization and automation of any step of a molecular diagnostic procedure possible. This review describes the application of microelectronics to all the processes involved in a genetic test, particularly to sample preparation, DNA amplification and sequence variation detection.
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Affiliation(s)
- Maurizio Ferrari
- IRCCS Ospedale San Raffaele, Head of the Clinical Molecular Biology & Cytogenetics Laboratory, Diagnostica e Ricerca San Raffaele SPA, and Unit of Genomics for Diagnosis of Human Pathologies, via Olgettina 60, 20132 Milan, Italy.
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Panaro NJ, Lou XJ, Fortina P, Kricka LJ, Wilding P. Micropillar array chip for integrated white blood cell isolation and PCR. ACTA ACUST UNITED AC 2005; 21:157-62. [PMID: 15748689 DOI: 10.1016/j.bioeng.2004.11.001] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2004] [Revised: 11/10/2004] [Accepted: 11/23/2004] [Indexed: 11/25/2022]
Abstract
We report the fabrication of silicon chips containing a row of 667 pillars, 10 by 20 microm in cross-section, etched to a depth of 80 microm with adjacent pillars being separated by 3.5 microm. The chips were used to separate white blood cells from whole blood in less than 2 min and for subsequent PCR of a genomic target (eNOS). Chip fluid dynamics were validated experimentally using CoventorWare microfluidic simulation software. The amplicon concentrations were determined using microchip capillary electrophoresis and were >40% of that observed in conventional PCR tubes for chips with and without pillars. Reproducible on-chip PCR was achieved using white blood cell preparations isolated from whole human blood pumped through the chip.
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Affiliation(s)
- Nicholas J Panaro
- Department of Pathology and Laboratory Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
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Fiorini GS, Chiu DT. Disposable microfluidic devices: fabrication, function, and application. Biotechniques 2005; 38:429-46. [PMID: 15786809 DOI: 10.2144/05383rv02] [Citation(s) in RCA: 245] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
This review article describes recent developments in microfluidics, with special emphasis on disposable plastic devices. Included is an overview of the common methods used in the fabrication of polymer microfluidic systems, including replica and injection molding, embossing, and laser ablation. Also described are the different methods by which on-chip operations--such as the pumping and valving of fluid flow, the mixing of different reagents, and the separation and detection of different chemical species--have been implemented in a microfluidic format. Finally, a few select biotechnological applications of microfluidics are presented to illustrate both the utility of this technology and its potential for development in the future.
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Cheng JY, Hsieh CJ, Chuang YC, Hsieh JR. Performing microchannel temperature cycling reactions using reciprocating reagent shuttling along a radial temperature gradient. Analyst 2005; 130:931-40. [PMID: 15912243 DOI: 10.1039/b501061f] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
This study develops a novel temperature cycling strategy for executing temperature cycling reactions in laser-etched poly(methylmethacrylate) (PMMA) microfluidic chips. The developed microfluidic chip is circular in shape and is clamped in contact with a circular ITO heater chip of an equivalent diameter. Both chips are fabricated using an economic and versatile laser scribing process. Using this arrangement, a self-sustained radial temperature gradient is generated within the microfluidic chip without the need to thermally isolate the different temperature zones. This study demonstrates the temperature cycling capabilities of the reported microfluidic device by a polymerase chain reaction (PCR) process using ribulose 1,5-bisphosphate carboxylase large subunit (rbcL) gene as a template. The temperature ramping rate of the sample inside the microchannel is determined from the spectral change of a thermochromic liquid crystal (TLC) solution pumped into the channel. The present results confirm that a rapid thermal cycling effect is achieved despite the low thermal conductivity of the PMMA substrate. Using IR thermometry, it is found that the radial temperature gradient of the chip is approximately 2 degrees C mm(-1). The simple system presented in this study has considerable potential for miniaturizing complex integrated reactions requiring different cycling parameters.
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Affiliation(s)
- Ji-Yen Cheng
- Research Center for Applied Sciences, 128 Sec. 2 Academia Rd., Taipei 11529, Taiwan.
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Shevkoplyas SS, Yoshida T, Munn LL, Bitensky MW. Biomimetic autoseparation of leukocytes from whole blood in a microfluidic device. Anal Chem 2005; 77:933-7. [PMID: 15679363 PMCID: PMC3022340 DOI: 10.1021/ac049037i] [Citation(s) in RCA: 167] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Leukocytes comprise less than 1% of all blood cells. Enrichment of their number, starting from a sample of whole blood, is the required first step of many clinical and basic research assays. We created a microfluidic device that takes advantage of the intrinsic features of blood flow in the microcirculation, such as plasma skimming and leukocyte margination, to separate leukocytes directly from whole blood. It consists of a simple network of rectangular microchannels designed to enhance lateral migration of leukocytes and their subsequent extraction from the erythrocyte-depleted region near the sidewalls. A single pass through the device produces a 34-fold enrichment of the leukocyte-to-erythrocyte ratio. It operates on microliter samples of whole blood, provides positive, continuous flow selection of leukocytes, and requires neither preliminary labeling of cells nor input of energy (except for a small pressure gradient to support the flow of blood). This effortless, efficient, and inexpensive technology can be used as a lab-on-a-chip component for initial whole blood sample preparation. Its integration into microanalytical devices that require leukocyte enrichment will enable accelerated transition of these devices into the field for point-of-care clinical testing.
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Affiliation(s)
| | | | - Lance L. Munn
- To whom correspondence should be addressed. E-mail: (S.S.S.) ; (L.L.M.) ; (M.W.B.)
| | - Mark W. Bitensky
- To whom correspondence should be addressed. E-mail: (S.S.S.) ; (L.L.M.) ; (M.W.B.)
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