1
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Lim J, Han W, Thang LTH, Lee YW, Shin JH. Customizable Nichrome Wire Heaters for Molecular Diagnostic Applications. BIOSENSORS 2024; 14:152. [PMID: 38534259 DOI: 10.3390/bios14030152] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/17/2024] [Revised: 03/09/2024] [Accepted: 03/19/2024] [Indexed: 03/28/2024]
Abstract
Accurate sample heating is vital for nucleic acid extraction and amplification, requiring a sophisticated thermal cycling process in nucleic acid detection. Traditional molecular detection systems with heating capability are bulky, expensive, and primarily designed for lab settings. Consequently, their use is limited where lab systems are unavailable. This study introduces a technique for performing the heating process required in molecular diagnostics applicable for point-of-care testing (POCT), by presenting a method for crafting customized heaters using freely patterned nichrome (NiCr) wire. This technique, fabricating heaters by arranging protrusions on a carbon black-polydimethylsiloxane (PDMS) cast and patterning NiCr wire, utilizes cost-effective materials and is not constrained by shape, thereby enabling customized fabrication in both two-dimensional (2D) and three-dimensional (3D). To illustrate its versatility and practicality, a 2D heater with three temperature zones was developed for a portable device capable of automatic thermocycling for polymerase chain reaction (PCR) to detect Escherichia coli (E. coli) O157:H7 pathogen DNA. Furthermore, the detection of the same pathogen was demonstrated using a customized 3D heater surrounding a microtube for loop-mediated isothermal amplification (LAMP). Successful DNA amplification using the proposed heater suggests that the heating technique introduced in this study can be effectively applied to POCT.
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Affiliation(s)
- Juhee Lim
- Industry 4.0 Convergence Bionics Engineering, Pukyong National University, Busan 48513, Republic of Korea
| | - Won Han
- Industry 4.0 Convergence Bionics Engineering, Pukyong National University, Busan 48513, Republic of Korea
| | - Le Tran Huy Thang
- Industry 4.0 Convergence Bionics Engineering, Pukyong National University, Busan 48513, Republic of Korea
| | - Yong Wook Lee
- Industry 4.0 Convergence Bionics Engineering, Pukyong National University, Busan 48513, Republic of Korea
- School of Electrical Engineering, Pukyong National University, Busan 48513, Republic of Korea
| | - Joong Ho Shin
- Industry 4.0 Convergence Bionics Engineering, Pukyong National University, Busan 48513, Republic of Korea
- Major of Biomedical Engineering, Division of Smart Healthcare, College of Information Technology and Convergence, Pukyong National University, Busan 48513, Republic of Korea
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2
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Yang B, Wang P, Li Z, You Q, Sekine S, Ma J, Zhuang S, Zhang D, Yamaguchi Y. Simultaneous amplification of DNA in a multiplex circular array shaped continuous flow PCR microfluidic chip for on-site detection of bacterial. LAB ON A CHIP 2023; 23:2633-2639. [PMID: 37170867 DOI: 10.1039/d3lc00274h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
Based on time to place conversion, continuous flow polymerase chain reaction (CF-PCR) can realize a rapid amplification of DNA by running the PCR reagent in a serpentine microchannel but a larger space is required for each sample, which greatly reduces the efficiency of the CF-PCR. Herein, we propose a multiplex circular array shaped CF-PCR microfluidic chip for on-site detection of bacteria. There were 12 serpentine microchannels which were distributed on the disc in an annular form, and each microchannel consisted of an inlet for sample injection, and an outlet for the detection of the PCR products based on fluorescence. Samples could be simultaneously driven into each inlet by a one-to-twelve diverter through a syringe. Moreover, the method of adding fluorescent dyes at the end of the microchannel can solve the inhibition effect of excessive fluorescent dyes on the PCR reaction. The process finished with simultaneous amplification of 12 different target genes from Porphyromonas gingivalis, Treponema denticola, Tannerella forsythia, and Escherichia coli, and on-site detection of their corresponding positives within 23 min. The fastest detectable PCR reaction time was 5.38 ± 0.2 min at a flow rate of 1 mL h-1. For E. coli, the minimum detectable concentration was 2.5 × 10-3 ng μL-1 in this microfluidic system. Such a system can increase the throughput of CF-PCR for point-of-care testing of pathogens.
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Affiliation(s)
- Bo Yang
- Engineering Research Center of Optical Instrument and System, Shanghai Environmental Biosafety Instruments and Equipment Engineering Technology Research Center, Key Lab of Optical Instruments and Equipment for Medical Engineering, Ministry of Education, Shanghai Key Lab of Modern Optical System, University of Shanghai for Science and Technology, Shanghai 200093, China.
| | - Ping Wang
- Department of Clinical Laboratory, Xinhua Hospital, Shanghai Jiao Tong University School of Medicine, 1665 Kongjiang Road, Shanghai 200092, China
| | - Zhenqing Li
- Engineering Research Center of Optical Instrument and System, Shanghai Environmental Biosafety Instruments and Equipment Engineering Technology Research Center, Key Lab of Optical Instruments and Equipment for Medical Engineering, Ministry of Education, Shanghai Key Lab of Modern Optical System, University of Shanghai for Science and Technology, Shanghai 200093, China.
| | - Qingxiang You
- Engineering Research Center of Optical Instrument and System, Shanghai Environmental Biosafety Instruments and Equipment Engineering Technology Research Center, Key Lab of Optical Instruments and Equipment for Medical Engineering, Ministry of Education, Shanghai Key Lab of Modern Optical System, University of Shanghai for Science and Technology, Shanghai 200093, China.
| | - Shinichi Sekine
- Department of Preventive Dentistry, Graduate School of Dentistry, Osaka University, Osaka 565-0871, Japan
| | - Junshan Ma
- Engineering Research Center of Optical Instrument and System, Shanghai Environmental Biosafety Instruments and Equipment Engineering Technology Research Center, Key Lab of Optical Instruments and Equipment for Medical Engineering, Ministry of Education, Shanghai Key Lab of Modern Optical System, University of Shanghai for Science and Technology, Shanghai 200093, China.
| | - Songlin Zhuang
- Engineering Research Center of Optical Instrument and System, Shanghai Environmental Biosafety Instruments and Equipment Engineering Technology Research Center, Key Lab of Optical Instruments and Equipment for Medical Engineering, Ministry of Education, Shanghai Key Lab of Modern Optical System, University of Shanghai for Science and Technology, Shanghai 200093, China.
| | - Dawei Zhang
- Engineering Research Center of Optical Instrument and System, Shanghai Environmental Biosafety Instruments and Equipment Engineering Technology Research Center, Key Lab of Optical Instruments and Equipment for Medical Engineering, Ministry of Education, Shanghai Key Lab of Modern Optical System, University of Shanghai for Science and Technology, Shanghai 200093, China.
| | - Yoshinori Yamaguchi
- Department of Applied Physics, Graduate School of Engineering, Osaka University, Osaka 565-0871, Japan.
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3
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Ren Y, Cao L, You M, Ji J, Gong Y, Ren H, Xu F, Guo H, Hu J, Li Z. “SMART” digital nucleic acid amplification technologies for lung cancer monitoring from early to advanced stages. Trends Analyt Chem 2022. [DOI: 10.1016/j.trac.2022.116774] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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4
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O'Connell KC, Lawless NK, Stewart BM, Landers JP. Dielectric heating of highly corrosive and oxidizing reagents on a hybrid glass microfiber-polymer centrifugal microfluidic device. LAB ON A CHIP 2022; 22:2549-2565. [PMID: 35674228 DOI: 10.1039/d2lc00221c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Many assays necessitate the use of highly concentrated acids, powerful oxidizing agents, or a combination of the two. Although microfluidic devices offer vast potential for rapid analytical interrogation at the point-of-need (PON), they cannot escape the fundamental requirement for reagent compatibility. Worse, many innovative protocols have been developed that would represent a significant improvement to current field-forward practices within their respective disciplines, but adoption falters due to chemical incompatibility with challenging reagents. Polymeric centrifugal microfluidic devices meet many of the needs for accommodating complex chemical or biochemical protocols in a multiplexed and automatable format. Yet, they also struggle to accommodate highly reactive chemical components long term. In this work, we report on a simple and inexpensive reagent storage strategy that bypasses the typical complexity involved with integration of liquid reagents on microfluidic devices. Moreover, we demonstrate microdevice compatibility and operation after six months of corrosive reagent storage as well as post dielectric heating. This new strategy allows for storage of multiple highly corrosive and oxidative reagents simultaneously, enhancing the possibilities for multistep assay integration at the PON for a diverse array of applications. Successful detection after one week of corrosive reagent storage of an illicit drug and neurotransmitter metabolite, for forensic and clinical applications, is demonstrated. Furthermore, environmental sample preparation via microwave-assisted wet acid digestion is performed on-disc and integrated with downstream detection. Quantitative detection of a heavy metal in soil is achieved by way of on-disc calibration and found to be accurate within 2.4% compared to a gold standard reference (ICP-OES).
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Affiliation(s)
- Killian C O'Connell
- Department of Chemistry, University of Virginia, Charlottesville, Virginia 22904, USA.
| | - Nicola K Lawless
- Department of Biology, University of Virginia, Charlottesville, Virginia 22904, USA
- Department of Cognitive Science, University of Virginia, Charlottesville, Virginia 22904, USA
| | - Brennan M Stewart
- Department of Biochemistry, University of Virginia, Charlottesville, Virginia 22904, USA
| | - James P Landers
- Department of Chemistry, University of Virginia, Charlottesville, Virginia 22904, USA.
- Department of Mechanical and Aerospace Engineering, University of Virginia, Charlottesville, Virginia 22904, USA
- Department of Pathology, University of Virginia, Charlottesville, Virginia 22904, USA
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5
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Oshimi K, Nishimura Y, Matsubara T, Tanaka M, Shikoh E, Zhao L, Zou Y, Komatsu N, Ikado Y, Takezawa Y, Kage-Nakadai E, Izutsu Y, Yoshizato K, Morita S, Tokunaga M, Yukawa H, Baba Y, Teki Y, Fujiwara M. Glass-patternable notch-shaped microwave architecture for on-chip spin detection in biological samples. LAB ON A CHIP 2022; 22:2519-2530. [PMID: 35510631 DOI: 10.1039/d2lc00112h] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
We report a notch-shaped coplanar microwave waveguide antenna on a glass plate designed for on-chip detection of optically detected magnetic resonance (ODMR) of fluorescent nanodiamonds (NDs). A lithographically patterned thin wire at the center of the notch area in the coplanar waveguide realizes a millimeter-scale ODMR detection area (1.5 × 2.0 mm2) and gigahertz-broadband characteristics with low reflection (∼8%). The ODMR signal intensity in the detection area is quantitatively predictable by numerical simulation. Using this chip device, we demonstrate a uniform ODMR signal intensity over the detection area for cells, tissue, and worms. The present demonstration of a chip-based microwave architecture will enable scalable chip integration of ODMR-based quantum sensing technology into various bioassay platforms.
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Affiliation(s)
- Keisuke Oshimi
- Department of Chemistry, Graduate School of Natural Science and Technology, Okayama University, Okayama 700-8530, Japan.
- Department of Chemistry, Graduate School of Science, Osaka City University, Osaka 558-8585, Japan
| | - Yushi Nishimura
- Department of Chemistry, Graduate School of Science, Osaka City University, Osaka 558-8585, Japan
- Institute for Quantum Life Science, Quantum Life and Medical Science Directorate, National Institutes for Quantum Science and Technology, Chiba 263-8555, Japan
| | - Tsutomu Matsubara
- Department of Anatomy and Regenerative Biology, Graduate School of Medicine, Osaka City University, Osaka 545-8585, Japan
| | - Masuaki Tanaka
- Department of Electrical and Information Engineering, Graduate School of Engineering, Osaka City University, Osaka 558-8585, Japan
| | - Eiji Shikoh
- Department of Electrical and Information Engineering, Graduate School of Engineering, Osaka City University, Osaka 558-8585, Japan
| | - Li Zhao
- State Key Laboratory of Radiation Medicine and Protection, School for Radiological and Interdisciplinary Sciences (RAD-X) and Collaborative Innovation Center of Radiation Medicine of Jiangsu Higher Education Institutions, Soochow University, Suzhou 215123, P. R. China
| | - Yajuan Zou
- Department of Chemistry, Graduate School of Natural Science and Technology, Okayama University, Okayama 700-8530, Japan.
- Graduate School of Human and Environmental Studies, Kyoto University, Kyoto 606-8501, Japan
| | - Naoki Komatsu
- Graduate School of Human and Environmental Studies, Kyoto University, Kyoto 606-8501, Japan
| | - Yuta Ikado
- Department of Chemistry, Graduate School of Natural Science and Technology, Okayama University, Okayama 700-8530, Japan.
| | - Yuka Takezawa
- Department of Human Life Science, Graduate School of Food and Human Life Science, Osaka City University, Osaka 558-8585, Japan
| | - Eriko Kage-Nakadai
- Department of Human Life Science, Graduate School of Food and Human Life Science, Osaka City University, Osaka 558-8585, Japan
| | - Yumi Izutsu
- Department of Biology, Faculty of Science, Niigata University, Niigata 950-2181, Japan
| | - Katsutoshi Yoshizato
- Synthetic biology laboratory, Graduate school of medicine, Osaka City University, Osaka 545-8585, Japan
| | - Saho Morita
- Department of Biomolecular Engineering, Graduate School of Engineering, Nagoya University, Nagoya 464-8603, Japan
| | - Masato Tokunaga
- Department of Biomolecular Engineering, Graduate School of Engineering, Nagoya University, Nagoya 464-8603, Japan
| | - Hiroshi Yukawa
- Department of Biomolecular Engineering, Graduate School of Engineering, Nagoya University, Nagoya 464-8603, Japan
- Institute of Nano-Life-Systems, Institutes of Innovation for Future Society, Nagoya University, Nagoya 464-8603, Japan
- Institute for Quantum Life Science, Quantum Life and Medical Science Directorate, National Institutes for Quantum Science and Technology, Chiba 263-8555, Japan
| | - Yoshinobu Baba
- Department of Biomolecular Engineering, Graduate School of Engineering, Nagoya University, Nagoya 464-8603, Japan
- Institute of Nano-Life-Systems, Institutes of Innovation for Future Society, Nagoya University, Nagoya 464-8603, Japan
- Institute for Quantum Life Science, Quantum Life and Medical Science Directorate, National Institutes for Quantum Science and Technology, Chiba 263-8555, Japan
| | - Yoshio Teki
- Department of Chemistry, Graduate School of Science, Osaka City University, Osaka 558-8585, Japan
| | - Masazumi Fujiwara
- Department of Chemistry, Graduate School of Natural Science and Technology, Okayama University, Okayama 700-8530, Japan.
- Department of Chemistry, Graduate School of Science, Osaka City University, Osaka 558-8585, Japan
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6
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Dong X, Liu L, Tu Y, Zhang J, Miao G, Zhang L, Ge S, Xia N, Yu D, Qiu X. Rapid PCR powered by microfluidics: A quick review under the background of COVID-19 pandemic. Trends Analyt Chem 2021; 143:116377. [PMID: 34188341 PMCID: PMC8223007 DOI: 10.1016/j.trac.2021.116377] [Citation(s) in RCA: 50] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
PCR has been widely used in different fields including molecular biology, pathogen detection, medical diagnosis, food detection and etc. However, the difficulty of promoting PCR in on-site point-of-care testing reflects on challenges relative to its speed, convenience, complexity, and even cost. With the emerging state-of-art of microfluidics, rapid PCR can be achieved with more flexible ways in micro-reactors. PCR plays a critical role in the detection of SARS-CoV-2. Under this special background of COVID-19 pandemic, this review focuses on the latest rapid microfluidic PCR. Rapid PCR is concluded in two main features, including the reactor (type, size, material) and the implementation of thermal cycling. Especially, the compromise between speed and sensitivity with microfluidic PCR is explored based on the system ratio of (thermal cycling time)/(reactor size). Representative applications about the detection of pathogens and SARS-CoV-2 viruses based on rapid PCR or other isothermal amplification are discussed as well.
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Affiliation(s)
- Xiaobin Dong
- Institute of Microfluidic Chip Development in Biomedical Engineering, College of Information Science and Technology, Beijing University of Chemical Technology, Beijing, 100029, China
| | - Luyao Liu
- Institute of Microfluidic Chip Development in Biomedical Engineering, College of Information Science and Technology, Beijing University of Chemical Technology, Beijing, 100029, China
| | - Yunping Tu
- Institute of Microfluidic Chip Development in Biomedical Engineering, College of Information Science and Technology, Beijing University of Chemical Technology, Beijing, 100029, China
| | - Jing Zhang
- Institute of Microfluidic Chip Development in Biomedical Engineering, College of Information Science and Technology, Beijing University of Chemical Technology, Beijing, 100029, China
| | - Guijun Miao
- Institute of Microfluidic Chip Development in Biomedical Engineering, College of Information Science and Technology, Beijing University of Chemical Technology, Beijing, 100029, China
| | - Lulu Zhang
- Institute of Microfluidic Chip Development in Biomedical Engineering, College of Information Science and Technology, Beijing University of Chemical Technology, Beijing, 100029, China
| | - Shengxiang Ge
- National Institute of Diagnostics and Vaccine Development in Infectious Diseases, Xiamen University, Xiamen, 361005, China
| | - Ningshao Xia
- National Institute of Diagnostics and Vaccine Development in Infectious Diseases, Xiamen University, Xiamen, 361005, China
| | - Duli Yu
- Institute of Microfluidic Chip Development in Biomedical Engineering, College of Information Science and Technology, Beijing University of Chemical Technology, Beijing, 100029, China
- Beijing Advanced Innovation Center for Soft Matter Science and Engineering, Beijing, 100029, China
| | - Xianbo Qiu
- Institute of Microfluidic Chip Development in Biomedical Engineering, College of Information Science and Technology, Beijing University of Chemical Technology, Beijing, 100029, China
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7
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Microfluidic Modules Integrated with Microwave Components-Overview of Applications from the Perspective of Different Manufacturing Technologies. SENSORS 2021; 21:s21051710. [PMID: 33801309 PMCID: PMC7958350 DOI: 10.3390/s21051710] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/30/2020] [Revised: 02/05/2021] [Accepted: 02/25/2021] [Indexed: 12/14/2022]
Abstract
The constant increase in the number of microfluidic-microwave devices can be explained by various advantages, such as relatively easy integration of various microwave circuits in the device, which contains microfluidic components. To achieve the aforementioned solutions, four trends of manufacturing appear—manufacturing based on epoxy-glass laminates, polymer materials (mostly common in use are polydimethylsiloxane (PDMS) and polymethyl 2-methylpropenoate (PMMA)), glass/silicon substrates, and Low-Temperature Cofired Ceramics (LTCCs). Additionally, the domains of applications the microwave-microfluidic devices can be divided into three main fields—dielectric heating, microwave-based detection in microfluidic devices, and the reactors for microwave-enhanced chemistry. Such an approach allows heating or delivering the microwave power to the liquid in the microchannels, as well as the detection of its dielectric parameters. This article consists of a literature review of exemplary solutions that are based on the above-mentioned technologies with the possibilities, comparison, and exemplary applications based on each aforementioned technology.
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8
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Progress in molecular detection with high-speed nucleic acids thermocyclers. J Pharm Biomed Anal 2020; 190:113489. [DOI: 10.1016/j.jpba.2020.113489] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2020] [Revised: 07/17/2020] [Accepted: 07/20/2020] [Indexed: 12/26/2022]
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9
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Design and Comparison of Resonant and Non-Resonant Single-Layer Microwave Heaters for Continuous Flow Microfluidics in Silicon-Glass Technology. ENERGIES 2020. [DOI: 10.3390/en13102635] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
This paper presents a novel concept for the co-design of microwave heaters and microfluidic channels for sub-microliter volumes in continuous flow microfluidics. Based on the novel co-design concept, two types of heaters are presented, co-designed and manufactured in high-resistivity silicon-glass technology, resulting in a building block for consumable and mass-producible micro total analysis systems. Resonant and non-resonant co-planar waveguide transmission line heaters are investigated for heating of sub-micro-liter liquid volumes in a channel section at 25 GHz. The heating rates of 16 and 24 °C/s are obtained with power levels of 32 dBm for the through line and the open-ended line microwave heater, respectively. The heating uniformity of developed devices is evaluated with a Rhodamine B and deionized water mixture on a micrometer scale using the microwave-optical measurement setup. Measurement results showed a good agreement with simulations and demonstrated the potential of microwave heating for microfluidics.
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10
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Novel Fabrication Process for Integration of Microwave Sensors in Microfluidic Channels. MICROMACHINES 2020; 11:mi11030320. [PMID: 32204493 PMCID: PMC7143474 DOI: 10.3390/mi11030320] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/20/2020] [Revised: 03/13/2020] [Accepted: 03/17/2020] [Indexed: 12/20/2022]
Abstract
This paper presents a novel fabrication process that allows integration of polydimethylsiloxane (PDMS)-based microfluidic channels and metal electrodes on a wafer with a micrometer-range alignment accuracy. This high level of alignment accuracy enables integration of microwave and microfluidic technologies, and furthermore accurate microwave dielectric characterization of biological liquids and chemical compounds on a nanoliter scale. The microfluidic interface between the pump feed lines and the fluidic channels was obtained using magnets fluidic connection. The tube-channel interference and the fluidic channel-wafer adhesion was evaluated, and up to a pressure of 700 mBar no leakage was observed. The developed manufacturing process was tested on a design of a microwave-microfluidic capacitive sensor. An interdigital capacitor (IDC) and a microfluidic channel were manufactured with an alignment accuracy of 2.5 μm. The manufactured IDC sensor was used to demonstrate microwave dielectric sensing on deionized water and saline solutions with concentrations of 0.1, 0.5, 1, and 2.5 M.
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11
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Miao G, Zhang L, Zhang J, Ge S, Xia N, Qian S, Yu D, Qiu X. Free convective PCR: From principle study to commercial applications-A critical review. Anal Chim Acta 2020; 1108:177-197. [PMID: 32222239 DOI: 10.1016/j.aca.2020.01.069] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2019] [Revised: 01/28/2020] [Accepted: 01/29/2020] [Indexed: 12/11/2022]
Abstract
Polymerase chain reaction (PCR) is an extremely important tool for molecular diagnosis, as it can specifically amplify nucleic acid templates for sensitive detection. As another division of PCR, free convective PCR was invented in 2001, which can be performed in a capillary tube pseudo-isothermally within a significantly short time. Convective PCR thermal cycling is implemented by inducing thermal convection inside the capillary tube, which stratifies the reaction into spatially separate and stable melting, annealing, and extension zones created by the temperature gradient. Convective PCR is a promising tool that can be used for nucleic acid diagnosis as a point-of-care test (POCT) due to the significantly simplified heating strategy, reduced cost, and shortened detection time without sacrificing sensitivity and accuracy. Here, we review the history of free convective PCR from its invention to development and its commercial applications.
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Affiliation(s)
- Guijun Miao
- Institute of Microfluidic Chip Development in Biomedical Engineering, College of Information Science and Technology, Beijing University of Chemical Technology, Beijing, 100029, China.
| | - Lulu Zhang
- Institute of Microfluidic Chip Development in Biomedical Engineering, College of Information Science and Technology, Beijing University of Chemical Technology, Beijing, 100029, China.
| | - Jing Zhang
- Institute of Microfluidic Chip Development in Biomedical Engineering, College of Information Science and Technology, Beijing University of Chemical Technology, Beijing, 100029, China.
| | - Shengxiang Ge
- National Institute of Diagnostics and Vaccine Development in Infectious Diseases, Xiamen University, Xiamen, 361005, China.
| | - Ningshao Xia
- National Institute of Diagnostics and Vaccine Development in Infectious Diseases, Xiamen University, Xiamen, 361005, China.
| | - Shizhi Qian
- Department of Mechanical and Aerospace Engineering, Old Dominion University, Norfolk, VA, 23529, USA.
| | - Duli Yu
- Institute of Microfluidic Chip Development in Biomedical Engineering, College of Information Science and Technology, Beijing University of Chemical Technology, Beijing, 100029, China; Beijing Advanced Innovation Center for Soft Matter Science and Engineering, Beijing, 100029, China.
| | - Xianbo Qiu
- Institute of Microfluidic Chip Development in Biomedical Engineering, College of Information Science and Technology, Beijing University of Chemical Technology, Beijing, 100029, China.
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12
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Ultrafast Photonic PCR Based on Photothermal Nanomaterials. Trends Biotechnol 2020; 38:637-649. [PMID: 31918858 DOI: 10.1016/j.tibtech.2019.12.006] [Citation(s) in RCA: 65] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2019] [Revised: 12/04/2019] [Accepted: 12/06/2019] [Indexed: 12/17/2022]
Abstract
Over the past few decades, PCR has been the gold standard for detecting nucleic acids (NAs) in various biomedical fields. However, there are several limitations associated with conventional PCR, such as complicated operation, need for bulky equipment, and, in particular, long thermocycling time. Emerging nanomaterials with photothermal effects have shown great potential for developing a new generation of PCR: ultrafast photonic PCR. Here, we review recent applications of photothermal nanomaterials in ultrafast photonic PCR. First, we introduce emerging photothermal nanomaterials and their light-to-heat energy conversion process in photonic PCR. We then review different photothermal nanomaterial-based photonic PCRs and compare their merits and drawbacks. Finally, we summarize existing challenges with photonic PCR and hypothesize its promising future research directions.
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13
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Sun J, Vanloon J, Yan H. Influence of microwave irradiation on DNA hybridization and polymerase reactions. Tetrahedron Lett 2019. [DOI: 10.1016/j.tetlet.2019.151060] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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14
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Lee SH, Park SM, Kim BN, Kwon OS, Rho WY, Jun BH. Emerging ultrafast nucleic acid amplification technologies for next-generation molecular diagnostics. Biosens Bioelectron 2019; 141:111448. [PMID: 31252258 DOI: 10.1016/j.bios.2019.111448] [Citation(s) in RCA: 53] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2019] [Revised: 05/31/2019] [Accepted: 06/17/2019] [Indexed: 02/07/2023]
Abstract
Over the last decade, nucleic acid amplification tests (NAATs) including polymerase chain reaction (PCR) were an indispensable methodology for diagnosing cancers, viral and bacterial infections owing to their high sensitivity and specificity. Because the NAATs can recognize and discriminate even a few copies of nucleic acid (NA) and species-specific NA sequences, NAATs have become the gold standard in a wide range of applications. However, limitations of NAAT approaches have recently become more apparent by reason of their lengthy run time, large reaction volume, and complex protocol. To meet the current demands of clinicians and biomedical researchers, new NAATs have developed to achieve ultrafast sample-to-answer protocols for the point-of-care testing (POCT). In this review, ultrafast NA-POCT platforms are discussed, outlining their NA amplification principles as well as delineating recent advances in ultrafast NAAT applications. The main focus is to provide an overview of NA-POCT platforms in regard to sample preparation of NA, NA amplification, NA detection process, interpretation of the analysis, and evaluation of the platform design. Increasing importance will be given to innovative, ultrafast amplification methods and tools which incorporate artificial intelligence (AI)-associated data analysis processes and mobile-healthcare networks. The future prospects of NA POCT platforms are promising as they allow absolute quantitation of NA in individuals which is essential to precision medicine.
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Affiliation(s)
- Sang Hun Lee
- Department of Bioengineering, University of California Berkeley, CA, USA
| | | | - Brian N Kim
- Department of Electrical and Computer Engineering, University of Central Florida, FL, USA
| | - Oh Seok Kwon
- Infectious Disease Research Center, Korea Research Institute of Bioscience & Biotechnology, Daejeon, South Korea
| | - Won-Yep Rho
- School of International Engineering and Science, Chonbuk National University, Jeonju, South Korea
| | - Bong-Hyun Jun
- Department of Bioscience and Biotechnology, Konkuk University, South Korea.
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Malecha K, Jasińska L, Grytsko A, Drzozga K, Słobodzian P, Cabaj J. Monolithic Microwave-Microfluidic Sensors Made with Low Temperature Co-Fired Ceramic (LTCC) Technology. SENSORS 2019; 19:s19030577. [PMID: 30704068 PMCID: PMC6386962 DOI: 10.3390/s19030577] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/02/2019] [Revised: 01/22/2019] [Accepted: 01/28/2019] [Indexed: 12/26/2022]
Abstract
This paper compares two types of microfluidic sensors that are designed for operation in ISM (Industrial, Scientific, Medical) bands at microwave frequencies of 2.45 GHz and 5.8 GHz. In the case of the first sensor, the principle of operation is based on the resonance phenomenon in a microwave circuit filled with a test sample. The second sensor is based on the interferometric principle and makes use of the superposition of two coherent microwave signals, where only one goes through a test sample. Both sensors are monolithic structures fabricated using low temperature co-fired ceramics (LTCCs). The LTCC-based microwave-microfluidic sensor properties are examined and compared by measuring their responses for various concentrations of two types of test fluids: one is a mixture of water/ethanol, and the other is dopamine dissolved in a buffer solution. The experiments show a linear response for the LTCC-based microwave-microfluidic sensors as a function of the concentration of the components in both test fluids.
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Affiliation(s)
- Karol Malecha
- Faculty of Microsystem Electronics and Photonics, Wrocław University of Science and Technology, Wybrzeże Wyspiańskiego 27, 50-370 Wrocław, Poland.
| | - Laura Jasińska
- Faculty of Microsystem Electronics and Photonics, Wrocław University of Science and Technology, Wybrzeże Wyspiańskiego 27, 50-370 Wrocław, Poland.
| | - Anna Grytsko
- Faculty of Electronics, Wrocław University of Science and Technology, Wybrzeże Wyspiańskiego 27, 50-370 Wrocław, Poland.
| | - Kamila Drzozga
- Faculty of Chemistry, Wrocław University of Science and Technology, Wybrzeże Wyspiańskiego 27, 50-370 Wrocław, Poland.
| | - Piotr Słobodzian
- Faculty of Electronics, Wrocław University of Science and Technology, Wybrzeże Wyspiańskiego 27, 50-370 Wrocław, Poland.
| | - Joanna Cabaj
- Faculty of Chemistry, Wrocław University of Science and Technology, Wybrzeże Wyspiańskiego 27, 50-370 Wrocław, Poland.
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Sreejith KR, Ooi CH, Jin J, Dao DV, Nguyen NT. Digital polymerase chain reaction technology - recent advances and future perspectives. LAB ON A CHIP 2018; 18:3717-3732. [PMID: 30402632 DOI: 10.1039/c8lc00990b] [Citation(s) in RCA: 70] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Digital polymerase chain reaction (dPCR) technology has remained a "hot topic" in the last two decades due to its potential applications in cell biology, genetic engineering, and medical diagnostics. Various advanced techniques have been reported on sample dispersion, thermal cycling and output monitoring of digital PCR. However, a fully automated, low-cost and handheld digital PCR platform has not been reported in the literature. This paper attempts to critically evaluate the recent developments in techniques for sample dispersion, thermal cycling and output evaluation for dPCR. The techniques are discussed in terms of hardware simplicity, portability, cost-effectiveness and suitability for automation. The present paper also discusses the research gaps observed in each step of dPCR and concludes with possible improvements toward portable, low-cost and automatic digital PCR systems.
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Affiliation(s)
- Kamalalayam Rajan Sreejith
- Queensland Micro- and Nanotechnology Centre, Griffith University, 170 Kessels Road, 4111 Queensland, Australia.
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17
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Ding XF, Wu Y, Qu WR, Fan M, Zhao YQ. Quinacrine pretreatment reduces microwave-induced neuronal damage by stabilizing the cell membrane. Neural Regen Res 2018; 13:449-455. [PMID: 29623929 PMCID: PMC5900507 DOI: 10.4103/1673-5374.228727] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Quinacrine, widely used to treat parasitic diseases, binds to cell membranes. We previously found that quinacrine pretreatment reduced microwave radiation damage in rat hippocampal neurons, but the molecular mechanism remains poorly understood. Considering the thermal effects of microwave radiation and the protective effects of quinacrine on heat damage in cells, we hypothesized that quinacrine would prevent microwave radiation damage to cells in a mechanism associated with cell membrane stability. To test this, we used retinoic acid to induce PC12 cells to differentiate into neuron-like cells. We then pretreated the neurons with quinacrine (20 and 40 mM) and irradiated them with 50 mW/cm2 microwaves for 3 or 6 hours. Flow cytometry, atomic force microscopy and western blot assays revealed that irradiated cells pretreated with quinacrine showed markedly less apoptosis, necrosis, and membrane damage, and greater expression of heat shock protein 70, than cells exposed to microwave irradiation alone. These results suggest that quinacrine stabilizes the neuronal membrane structure by upregulating the expression of heat shock protein 70, thus reducing neuronal injury caused by microwave radiation.
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Affiliation(s)
- Xue-Feng Ding
- Department of Cognitive Sciences, Beijing Institute of Basic Medical Sciences, Beijing, China
| | - Yan Wu
- Department of Cognitive Sciences, Beijing Institute of Basic Medical Sciences, Beijing, China
| | - Wen-Rui Qu
- Hand & Foot Surgery and Reparative & Reconstructive Surgery Center, Orthopedic Hospital of the Second Hospital of Jilin University, Changchun, Jilin Province, China
| | - Ming Fan
- Department of Cognitive Sciences, Beijing Institute of Basic Medical Sciences, Beijing, China
| | - Yong-Qi Zhao
- Department of Cognitive Sciences, Beijing Institute of Basic Medical Sciences, Beijing, China
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18
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Pillet F, Gibot L, Catrain A, Kolosnjaj-Tabi J, Courtois K, Chretiennot T, Bellard E, Tarayre J, Golzio M, Vezinet R, Rols MP. High power electromagnetic pulse applicators for evaluation of biological effects induced by electromagnetic radiation waves. RSC Adv 2018; 8:16319-16329. [PMID: 35542224 PMCID: PMC9080243 DOI: 10.1039/c8ra00330k] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2018] [Accepted: 04/25/2018] [Indexed: 11/21/2022] Open
Abstract
Micro applicators for real-time observation of electromagnetic radiation waves effects on giant unilamellar vesicles and mammalian cells.
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Affiliation(s)
- Flavien Pillet
- Institut de Pharmacologie et de Biologie Structurale, IPBS
- Université de Toulouse
- CNRS
- UPS
- Toulouse
| | - Laure Gibot
- Institut de Pharmacologie et de Biologie Structurale, IPBS
- Université de Toulouse
- CNRS
- UPS
- Toulouse
| | | | - Jelena Kolosnjaj-Tabi
- Institut de Pharmacologie et de Biologie Structurale, IPBS
- Université de Toulouse
- CNRS
- UPS
- Toulouse
| | - Kristelle Courtois
- Institut de Pharmacologie et de Biologie Structurale, IPBS
- Université de Toulouse
- CNRS
- UPS
- Toulouse
| | | | - Elisabeth Bellard
- Institut de Pharmacologie et de Biologie Structurale, IPBS
- Université de Toulouse
- CNRS
- UPS
- Toulouse
| | | | - Muriel Golzio
- Institut de Pharmacologie et de Biologie Structurale, IPBS
- Université de Toulouse
- CNRS
- UPS
- Toulouse
| | | | - Marie-Pierre Rols
- Institut de Pharmacologie et de Biologie Structurale, IPBS
- Université de Toulouse
- CNRS
- UPS
- Toulouse
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19
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Microfluidical Microwave Reactor for Synthesis of Gold Nanoparticles. MICROMACHINES 2017; 8:mi8110318. [PMID: 30400507 PMCID: PMC6189920 DOI: 10.3390/mi8110318] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/08/2017] [Revised: 10/23/2017] [Accepted: 10/23/2017] [Indexed: 11/16/2022]
Abstract
Microwave treatment can reduce the time of selected syntheses, for instance of gold nanoparticles (AuNPs), from several hours to a few minutes. We propose a microfluidic structure for enhancing the rate of chemical reactions using microwave energy. This reactor is designed to control microwave energy with much higher accuracy than in standard devices. Thanks to this, the influence of microwave irradiation on the rate of chemical reactions can be investigated. The reactor consists of a transmission line surrounded by ground metallization. In order to deliver microwave energy to the fluid under test efficiently, matching networks are used and optimized by means of numerical methods. The monolithic device is fabricated in the low temperature co-fired ceramics (LTCC) technology. This material exhibits excellent microwave performance and is resistant to many chemical substances as well as high temperatures. Fabrication of the devices is described in detail. Measurements of microwave parameters are performed and differences between simulation and experiment results are discussed. Finally, the usefulness of the proposed device is proved in exemplary synthesis.
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20
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Qiu X, Zhang S, Mei L, Wu D, Guo Q, Li K, Ge S, Ye X, Xia N, Mauk MG. Characterization and analysis of real-time capillary convective PCR toward commercialization. BIOMICROFLUIDICS 2017; 11:024103. [PMID: 28798846 PMCID: PMC5533481 DOI: 10.1063/1.4977841] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/07/2017] [Accepted: 02/20/2017] [Indexed: 05/30/2023]
Abstract
Almost all the reported capillary convective polymerase chain reaction (CCPCR) systems to date are still limited to research use stemming from unresolved issues related to repeatability, reliability, convenience, and sensitivity. To move CCPCR technology forward toward commercialization, a couple of critical strategies and innovations are discussed here. First, single- and dual-end heating strategies are analyzed and compared between each other. Especially, different solutions for dual-end heating are proposed and discussed, and the heat transfer and fluid flow inside the capillary tube with an optimized dual-end heating strategy are analyzed and modeled. Second, real-time CCPCR is implemented with light-emitting diode and photodiode, and the real-time fluorescence detection method is compared with the post-amplification end-point detection method based on a dipstick assay. Thirdly, to reduce the system complexity, e.g., to simplify parameter tuning of the feedback control, an internal-model-control-based proportional-integral-derivative controller is adopted for accurate temperature control. Fourth, as a proof of concept, CCPCR with pre-loaded dry storage of reagent inside the capillary PCR tube is evaluated to better accommodate to point-of-care diagnosis. The critical performances of improved CCPCR, especially with sensitivity, repeatability, and reliability, have been thoroughly analyzed with different experiments using influenza A (H1N1) virus as the detection sample.
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Affiliation(s)
- Xianbo Qiu
- Institute of Microfluidic Chip Development in Biomedical Engineering, College of Information Science and Technology, Beijing University of Chemical Technology, Beijing 100029, China
| | - Shiyin Zhang
- National Institute of Diagnostics and Vaccine Development in Infectious Diseases, Xiamen University, Xiamen 361005, China
| | - Lanju Mei
- Institute of Micro/Nanotechnology, Old Dominion University, Norfolk, Virginia 23529, USA
| | - Di Wu
- Institute of Microfluidic Chip Development in Biomedical Engineering, College of Information Science and Technology, Beijing University of Chemical Technology, Beijing 100029, China
| | - Qi Guo
- Institute of Microfluidic Chip Development in Biomedical Engineering, College of Information Science and Technology, Beijing University of Chemical Technology, Beijing 100029, China
| | - Ke Li
- Beijing Wantai Biological Pharmacy Enterprise Co., Ltd., Beijing 102206, China
| | - Shengxiang Ge
- National Institute of Diagnostics and Vaccine Development in Infectious Diseases, Xiamen University, Xiamen 361005, China
| | - Xiangzhong Ye
- Beijing Wantai Biological Pharmacy Enterprise Co., Ltd., Beijing 102206, China
| | - Ningshao Xia
- National Institute of Diagnostics and Vaccine Development in Infectious Diseases, Xiamen University, Xiamen 361005, China
| | - Michael G Mauk
- Department of Mechanical Engineering and Applied Mechanics, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
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21
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Qiu X, Ge S, Gao P, Li K, Yang Y, Zhang S, Ye X, Xia N, Qian S. A Low-Cost and Fast Real-Time PCR System Based on Capillary Convection. SLAS Technol 2016; 22:13-17. [PMID: 27272156 DOI: 10.1177/2211068216652847] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
A low-cost and fast real-time PCR system in a pseudo-isothermal manner with disposable capillary tubes based on thermal convection for point-of-care diagnostics is developed and tested. Once stable temperature gradient along the capillary tube has been established, a continuous circulatory flow or thermal convection inside the capillary tube will repeatedly transport PCR reagents through temperature zones associated with the DNA denaturing, annealing, and extension stages of the reaction. To establish stable temperature gradient along the capillary tube, a dual-temperature heating strategy with top and bottom heaters is adopted here. A thermal waveguide is adopted for precise maintenance of the temperature of the top heater. An optimized optical network is developed for monitoring up to eight amplification units for real-time fluorescence detection. The system performance was demonstrated with repeatable detection of influenza A (H1N1) virus nucleic acid targets with a limit of detection of 1.0 TCID50/mL within 30 min.
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Affiliation(s)
- Xianbo Qiu
- 1 College of Information Science and Technology, Beijing University of Chemical Technology, Beijing, China
| | - Shengxiang Ge
- 2 National Institute of Diagnostics and Vaccine Development in Infectious Diseases, Xiamen University, Xiamen, China
| | - Pengfei Gao
- 1 College of Information Science and Technology, Beijing University of Chemical Technology, Beijing, China
| | - Ke Li
- 3 Beijing Wantai Biological Pharmacy Enterprise Co. Ltd., Beijing, China
| | - Yongliang Yang
- 1 College of Information Science and Technology, Beijing University of Chemical Technology, Beijing, China
| | - Shiyin Zhang
- 2 National Institute of Diagnostics and Vaccine Development in Infectious Diseases, Xiamen University, Xiamen, China
| | - Xiangzhong Ye
- 3 Beijing Wantai Biological Pharmacy Enterprise Co. Ltd., Beijing, China
| | - Ningshao Xia
- 2 National Institute of Diagnostics and Vaccine Development in Infectious Diseases, Xiamen University, Xiamen, China
| | - Shizhi Qian
- 4 Institute of Micro/Nanotechnology, Old Dominion University, Norfolk, VA, USA
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22
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Acoustothermal heating of polydimethylsiloxane microfluidic system. Sci Rep 2015; 5:11851. [PMID: 26138310 PMCID: PMC4490350 DOI: 10.1038/srep11851] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2015] [Accepted: 06/05/2015] [Indexed: 12/20/2022] Open
Abstract
We report an observation of rapid (exceeding 2,000 K/s) heating of polydimethylsiloxane (PDMS), one of the most popular microchannel materials, under cyclic loadings at high (~MHz) frequencies. A microheater was developed based on the finding. The heating mechanism utilized vibration damping in PDMS induced by sound waves that were generated and precisely controlled using a conventional surface acoustic wave (SAW) microfluidic system. The refraction of SAW into the PDMS microchip, called the leaky SAW, takes a form of bulk wave and rapidly heats the microchannels in a volumetric manner. The penetration depths were measured to range from 210 μm to 1290 μm, enough to cover most sizes of microchannels. The energy conversion efficiency was SAW frequency-dependent and measured to be the highest at around 30 MHz. Independent actuation of each interdigital transducer (IDT) enabled independent manipulation of SAWs, permitting spatiotemporal control of temperature on the microchip. All the advantages of this microheater facilitated a two-step continuous flow polymerase chain reaction (CFPCR) to achieve the billion-fold amplification of a 134 bp DNA amplicon in less than 3 min.
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23
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Schrell AM, Roper MG. Frequency-encoded laser-induced fluorescence for multiplexed detection in infrared-mediated quantitative PCR. Analyst 2015; 139:2695-701. [PMID: 24448431 DOI: 10.1039/c3an02334f] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A frequency-modulated fluorescence encoding method was used as a means to increase the number of fluorophores monitored during infrared-mediated polymerase chain reaction. Laser lines at 488 nm and 561 nm were modulated at 73 and 137 Hz, respectively, exciting fluorescence from the dsDNA intercalating dye, EvaGreen, and the temperature insensitive dye, ROX. Emission was collected in a color-blind manner using a single photomultiplier tube for detection and demodulated by frequency analysis. The resulting frequency domain signal resolved the contribution from the two fluorophores as well as the background from the IR lamp. The detection method was successfully used to measure amplification of DNA samples containing 10(4)-10(7) starting copies of template producing an amplification efficiency of 96%. The utility of this methodology was further demonstrated by simultaneous amplification of two genes from human genomic DNA using different color TaqMan probes. This method of multiplexing fluorescence detection with IR-qPCR is ideally suited as it allows isolation of the signals of interest from the background in the frequency domain and is expected to further reduce the complexity of multiplexed microfluidic IR-qPCR instrumentation.
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Affiliation(s)
- Adrian M Schrell
- Department of Chemistry and Biochemistry, Florida State University, 95 Chieftain Way, Dittmer Building, Tallahassee, FL 32306, USA.
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