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Zhang J, Li M, Xu R, Kapur S, Bombard A, Song Y. Electrokinetics in antimicrobial resistance analysis: A review. Electrophoresis 2023; 44:323-336. [PMID: 35940104 DOI: 10.1002/elps.202200153] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2022] [Revised: 07/23/2022] [Accepted: 08/03/2022] [Indexed: 02/01/2023]
Abstract
Infections caused by antimicrobial resistance are a serious problem in the world. Currently, commercial devices for antimicrobial susceptibility testing and resistant bacteria identification are time-consuming. There is an urgent need to develop fast and accurate methods, especially in the process of sample pretreatment. Electrokinetic (EK) is a family of electric-field-based kinetic phenomena of fluid or embedded objects, and EK applications have been found in various fields. In this paper, EK bacteria manipulation, including enrichment and separation, is reviewed. Focus is given to the rapid electric-based minimum inhibitory concentration measurement. The future directions and major challenges in this field are also outlined.
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Affiliation(s)
- Junyan Zhang
- Department of Marine Engineering, Dalian Maritime University, Dalian, P. R. China
| | - Mengqi Li
- Department of Marine Engineering, Dalian Maritime University, Dalian, P. R. China
| | - Runxin Xu
- Department of Navigation, Dalian Maritime University, Dalian, P. R. China
| | - Suman Kapur
- Department of Biological Sciences, Birla Institute of Technology and Science, Pilani, Hyderabad Campus, Hyderabad, Telangana, India
| | - Antonio Bombard
- Physics and Chemistry Institute, Federal University of Itajubá, Itajubá, Brazil
| | - Yongxin Song
- Department of Marine Engineering, Dalian Maritime University, Dalian, P. R. China
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2
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Panklang N, Techaumnat B, Wisitsoraat A, Putaporntip C, Chotivanich K, Suzuki Y. A discrete dielectrophoresis device for the separation of malaria‐infected cells. Electrophoresis 2022; 43:1347-1356. [DOI: 10.1002/elps.202100271] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2021] [Revised: 03/07/2022] [Accepted: 03/11/2022] [Indexed: 11/06/2022]
Affiliation(s)
- Nitipong Panklang
- Department of Electrical Engineering Faculty of Engineering Chulalongkorn University Bangkok Thailand
| | - Boonchai Techaumnat
- Department of Electrical Engineering Faculty of Engineering Chulalongkorn University Bangkok Thailand
- Biomedical Engineering Research Center Faculty of Engineering Chulalongkorn University Bangkok Thailand
| | - Anurat Wisitsoraat
- Nanoelectronics and MEMS Laboratory National Electronics and Computer Technology Center Pathumthani Thailand
| | - Chaturong Putaporntip
- Molecular Biology of Malaria and Opportunistic Parasites Research Unit Department of Parasitology Faculty of Medicine Chulalongkorn University Bangkok Thailand
| | - Kesinee Chotivanich
- Department of Clinical Tropical Medicine Mahidol Oxford Tropical Medicine Research Unit Faculty of Tropical Medicine Mahidol University Bangkok Thailand
| | - Yuji Suzuki
- Department of Mechanical Engineering The University of Tokyo Tokyo Japan
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3
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Alias AB, Mishra S, Pendharkar G, Chen CS, Liu CH, Liu YJ, Yao DJ. Microfluidic Microalgae System: A Review. MOLECULES (BASEL, SWITZERLAND) 2022; 27:molecules27061910. [PMID: 35335274 PMCID: PMC8954360 DOI: 10.3390/molecules27061910] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/27/2022] [Revised: 03/07/2022] [Accepted: 03/09/2022] [Indexed: 01/14/2023]
Abstract
Microalgae that have recently captivated interest worldwide are a great source of renewable, sustainable and economical biofuels. The extensive potential application in the renewable energy, biopharmaceutical and nutraceutical industries have made them necessary resources for green energy. Microalgae can substitute liquid fossil fuels based on cost, renewability and environmental concern. Microfluidic-based systems outperform their competitors by executing many functions, such as sorting and analysing small volumes of samples (nanolitre to picolitre) with better sensitivities. In this review, we consider the developing uses of microfluidic technology on microalgal processes such as cell sorting, cultivation, harvesting and applications in biofuels and biosensing.
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Affiliation(s)
- Anand Baby Alias
- Institute of NanoEngineering and MicroSystems, National Tsing Hua University, Hsinchu 30013, Taiwan; (A.B.A.); (S.M.); (C.-H.L.)
| | - Shubhanvit Mishra
- Institute of NanoEngineering and MicroSystems, National Tsing Hua University, Hsinchu 30013, Taiwan; (A.B.A.); (S.M.); (C.-H.L.)
| | - Gaurav Pendharkar
- Department of Power Mechanical Engineering, National Tsing Hua University, Hsinchu 30013, Taiwan;
| | - Chi-Shuo Chen
- Department of Biomedical Engineering and Environmental Sciences, National Tsing Hua University, Hsinchu 30013, Taiwan;
| | - Cheng-Hsien Liu
- Institute of NanoEngineering and MicroSystems, National Tsing Hua University, Hsinchu 30013, Taiwan; (A.B.A.); (S.M.); (C.-H.L.)
- Department of Power Mechanical Engineering, National Tsing Hua University, Hsinchu 30013, Taiwan;
| | - Yi-Ju Liu
- Food Industry Research and Development Institute, Hsinchu 300193, Taiwan;
| | - Da-Jeng Yao
- Institute of NanoEngineering and MicroSystems, National Tsing Hua University, Hsinchu 30013, Taiwan; (A.B.A.); (S.M.); (C.-H.L.)
- Department of Power Mechanical Engineering, National Tsing Hua University, Hsinchu 30013, Taiwan;
- Correspondence:
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4
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Lapizco-Encinas BH. The latest advances on nonlinear insulator-based electrokinetic microsystems under direct current and low-frequency alternating current fields: a review. Anal Bioanal Chem 2021; 414:885-905. [PMID: 34664103 DOI: 10.1007/s00216-021-03687-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2021] [Revised: 09/17/2021] [Accepted: 09/21/2021] [Indexed: 12/11/2022]
Abstract
This review article presents an overview of the evolution of the field of insulator-based dielectrophoresis (iDEP); in particular, it focuses on insulator-based electrokinetic (iEK) systems stimulated with direct current and low-frequency(< 1 kHz) AC electric fields. The article covers the surge of iDEP as a research field where many different device designs were developed, from microchannels with arrays of insulating posts to devices with curved walls and nano- and micropipettes. All of these systems allowed for the manipulation and separation of a wide array of particles, ranging from macromolecules to microorganisms, including clinical and biomedical applications. Recent experimental reports, supported by important theoretical studies in the field of physics and colloids, brought attention to the effects of electrophoresis of the second kind in these systems. These recent findings suggest that DEP is not the main force behind particle trapping, as it was believed for the last two decades. This new research suggests that particle trapping, under DC and low-frequency AC potentials, mainly results from a balance between electroosmotic and electrophoretic effects (linear and nonlinear); although DEP is present in these systems, it is not a dominant force. Considering these recent studies, it is proposed to rename this field from DC-iDEP to DC-iEK (and low-frequency AC-iDEP to low-frequency AC-iEK). Whereas much research is still needed, this is an exciting time in the field of microscale EK systems, as these new findings seem to explain the challenges with modeling particle migration and trapping in iEK devices, and provide perhaps a better understanding of the mechanisms behind particle trapping.
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Affiliation(s)
- Blanca H Lapizco-Encinas
- Microscale Bioseparations Laboratory and Biomedical Engineering Department, Rochester Institute of Technology, Institute Hall (Bldg. 73), Room 3103, 160 Lomb Memorial Drive, Rochester, NY, 14623-5604, USA.
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5
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Ma Z, Zhao H, Shi L, Yu D, Guo X. Automatic medium exchange for micro-volume cell samples based on dielectrophoresis. Electrophoresis 2021; 42:1507-1515. [PMID: 33990980 DOI: 10.1002/elps.202000195] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2020] [Revised: 03/27/2021] [Accepted: 04/20/2021] [Indexed: 11/06/2022]
Abstract
Cell medium exchange is a crucial step for life science and medicine. However, conventional cell medium exchange methods, including centrifuging and filtering, show limited ability for micro-volume cell samples such as circulating tumor cell (CTC) and circulating fetal cell (CFC). In this paper, we proposed an automatic medium exchange method for micro-volume cell samples based on dielectrophoresis (DEP) in microfluidic chip. Fresh medium and cell suspension were introduced into the microfluidic channel as the laminar flow. Plane stair-shaped interdigital electrodes were employed to drive the cells from the cell suspension to fresh media directly by DEP force. Additionally, we characterized and optimized the cell medium exchange according to both the theory and experiments. In the end, we achieved a 96.9% harvest rate of medium exchange for 0.3 μL samples containing micro-volume cells. For implementing an automatic continuous cell medium exchange, the proposed method can be integrated into the automatic cell processing system conveniently. Furthermore, the proposed method is a great candidate in micro-volume cell analysis and processing, cell electroporation, single cell sequencing, and other scenarios.
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Affiliation(s)
- Zhouyang Ma
- College of Information Science and Technology, Beijing University of Chemical Technology, Beijing, P. R. China
| | - Hongwang Zhao
- School of Automobile and Traffic Engineering, Guilin University of Aerospace Technology, Guilin, Guangxi, P. R. China
| | - Liujia Shi
- State Key Laboratory of Space Medicine Fundamentals and Application, China Astronaut Research and Training Center, Beijing, P. R. China
| | - Duli Yu
- College of Information Science and Technology, Beijing University of Chemical Technology, Beijing, P. R. China.,Beijing Advance Innovation Center for Soft Matter Science and Engineering, Beijing, P. R. China
| | - Xiaoliang Guo
- College of Information Science and Technology, Beijing University of Chemical Technology, Beijing, P. R. China
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6
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Xuan X. Review of nonlinear electrokinetic flows in insulator-based dielectrophoresis: From induced charge to Joule heating effects. Electrophoresis 2021; 43:167-189. [PMID: 33991344 DOI: 10.1002/elps.202100090] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2021] [Revised: 05/08/2021] [Accepted: 05/11/2021] [Indexed: 01/03/2023]
Abstract
Insulator-based dielectrophoresis (iDEP) has been increasingly used for particle manipulation in various microfluidic applications. It exploits insulating structures to constrict and/or curve electric field lines to generate field gradients for particle dielectrophoresis. However, the presence of these insulators, especially those with sharp edges, causes two nonlinear electrokinetic flows, which, if sufficiently strong, may disturb the otherwise linear electrokinetic motion of particles and affect the iDEP performance. One is induced charge electroosmotic (ICEO) flow because of the polarization of the insulators, and the other is electrothermal flow because of the amplified Joule heating in the fluid around the insulators. Both flows vary nonlinearly with the applied electric field (either DC or AC) and exhibit in the form of fluid vortices, which have been utilized to promote some applications while being suppressed in others. The effectiveness of iDEP benefits from a comprehensive understanding of the nonlinear electrokinetic flows, which is complicated by the involvement of the entire iDEP device into electric polarization and thermal diffusion. This article is aimed to review the works on both the fundamentals and applications of ICEO and electrothermal flows in iDEP microdevices. A personal perspective of some future research directions in the field is also given.
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Affiliation(s)
- Xiangchun Xuan
- Department of Mechanical Engineering, Clemson University, Clemson, South Carolina, USA
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7
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Subramanian S, Huiszoon RC, Chu S, Bentley WE, Ghodssi R. Microsystems for biofilm characterization and sensing - A review. Biofilm 2020; 2:100015. [PMID: 33447801 PMCID: PMC7798443 DOI: 10.1016/j.bioflm.2019.100015] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2019] [Revised: 11/11/2019] [Accepted: 11/26/2019] [Indexed: 11/30/2022] Open
Abstract
Biofilms are the primary cause of clinical bacterial infections and are impervious to typical amounts of antibiotics, necessitating very high doses for elimination. Therefore, it is imperative to have suitable methods for characterization to develop novel methods of treatment that can complement or replace existing approaches using significantly lower doses of antibiotics. This review presents some of the current developments in microsystems for characterization and sensing of bacterial biofilms. Initially, we review current standards for studying biofilms that are based on invasive and destructive end-point biofilm characterization. Additionally, biofilm formation and growth is extremely sensitive to various growth and environmental parameters that cause large variability in biofilms between repeated experiments, making it very difficult to compare experimental repeats and characterize the temporal characteristics of these organisms. To address these challenges, recent developments in the field have moved toward systems and miniature devices that can aid in the non-invasive characterization of bacterial biofilms. Our review focuses on several types of microsystems for biofilm evaluation including optical, electrochemical, and mechanical systems. This review will show how these devices can lead to better understanding of the physiology and function of these communities of bacteria, which can eventually lead to the development of novel treatments that do not rely on high-dosage antibiotics.
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Affiliation(s)
- Sowmya Subramanian
- MEMS Sensors and Actuators Laboratory, University of Maryland, College Park, MD, USA
- Department of Electrical and Computer Engineering, University of Maryland, College Park, MD, USA
- Institute for Systems Research, University of Maryland, College Park, MD, USA
| | - Ryan C. Huiszoon
- MEMS Sensors and Actuators Laboratory, University of Maryland, College Park, MD, USA
- Institute for Systems Research, University of Maryland, College Park, MD, USA
- Fischell Department of Bioengineering, University of Maryland, College Park, MD, USA
- Robert E. Fischell Institute for Biomedical Devices, University of Maryland, College Park, MD, USA
| | - Sangwook Chu
- MEMS Sensors and Actuators Laboratory, University of Maryland, College Park, MD, USA
- Institute for Systems Research, University of Maryland, College Park, MD, USA
- Robert E. Fischell Institute for Biomedical Devices, University of Maryland, College Park, MD, USA
| | - William E. Bentley
- Fischell Department of Bioengineering, University of Maryland, College Park, MD, USA
- Robert E. Fischell Institute for Biomedical Devices, University of Maryland, College Park, MD, USA
| | - Reza Ghodssi
- MEMS Sensors and Actuators Laboratory, University of Maryland, College Park, MD, USA
- Department of Electrical and Computer Engineering, University of Maryland, College Park, MD, USA
- Institute for Systems Research, University of Maryland, College Park, MD, USA
- Fischell Department of Bioengineering, University of Maryland, College Park, MD, USA
- Robert E. Fischell Institute for Biomedical Devices, University of Maryland, College Park, MD, USA
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8
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Çağlayan Z, Demircan Yalçın Y, Külah H. A Prominent Cell Manipulation Technique in BioMEMS: Dielectrophoresis. MICROMACHINES 2020; 11:E990. [PMID: 33153069 PMCID: PMC7693018 DOI: 10.3390/mi11110990] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Revised: 10/22/2020] [Accepted: 10/28/2020] [Indexed: 12/17/2022]
Abstract
BioMEMS, the biological and biomedical applications of micro-electro-mechanical systems (MEMS), has attracted considerable attention in recent years and has found widespread applications in disease detection, advanced diagnosis, therapy, drug delivery, implantable devices, and tissue engineering. One of the most essential and leading goals of the BioMEMS and biosensor technologies is to develop point-of-care (POC) testing systems to perform rapid prognostic or diagnostic tests at a patient site with high accuracy. Manipulation of particles in the analyte of interest is a vital task for POC and biosensor platforms. Dielectrophoresis (DEP), the induced movement of particles in a non-uniform electrical field due to polarization effects, is an accurate, fast, low-cost, and marker-free manipulation technique. It has been indicated as a promising method to characterize, isolate, transport, and trap various particles. The aim of this review is to provide fundamental theory and principles of DEP technique, to explain its importance for the BioMEMS and biosensor fields with detailed references to readers, and to identify and exemplify the application areas in biosensors and POC devices. Finally, the challenges faced in DEP-based systems and the future prospects are discussed.
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Affiliation(s)
- Zeynep Çağlayan
- Department of Electrical and Electronics Engineering, Middle East Technical University, Ankara 06800, Turkey; (Z.Ç.); (Y.D.Y.)
- METU MEMS Research and Application Center, Ankara 06800, Turkey
| | - Yağmur Demircan Yalçın
- Department of Electrical and Electronics Engineering, Middle East Technical University, Ankara 06800, Turkey; (Z.Ç.); (Y.D.Y.)
- Mikro Biyosistemler Electronics Inc., Ankara 06530, Turkey
| | - Haluk Külah
- Department of Electrical and Electronics Engineering, Middle East Technical University, Ankara 06800, Turkey; (Z.Ç.); (Y.D.Y.)
- METU MEMS Research and Application Center, Ankara 06800, Turkey
- Mikro Biyosistemler Electronics Inc., Ankara 06530, Turkey
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9
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One-Step Hot Microembossing for Fabrication of Paper-Based Microfluidic Chips in 10 Seconds. Polymers (Basel) 2020; 12:polym12112493. [PMID: 33120953 PMCID: PMC7692775 DOI: 10.3390/polym12112493] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2020] [Revised: 10/23/2020] [Accepted: 10/26/2020] [Indexed: 12/12/2022] Open
Abstract
In recent years, microfluidic paper-based analytical devices (µPADs) have been developed because they are simple, inexpensive and power-free for low-cost chemical, biological and environmental detection. Moreover, paper is lightweight; easy to stack, store and transport; biodegradable; biocompatible; good for colorimetric tests; flammable for easy disposal of used paper-based diagnostic devices by incineration; and can be chemically modified. Different methods have been demonstrated to fabricate µPADs such as solid wax printing, craft cutting, photolithography, etc. In this study, one-step hot microembossing was proposed and demonstrated to fabricate µPADs. The processing parameters like embossing temperature, pressure and time were systematically investigated. It was found that, at 55 °C embossing temperature, the embossing pressure ranging from 10 to 14 MPa could be applied and the embossing time was only 5 s. This led to the overall processing time for fabrication of µPADs within 10 s. Glucose detection was conducted using the µPADs as fabricated, and a linear relationship was obtained between 5 and 50 mM.
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10
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Waheed W, Alazzam A, Al-Khateeb AN, Abu-Nada E. Multiple Particle Manipulation under Dielectrophoresis Effect: Modeling and Experiments. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2020; 36:3016-3028. [PMID: 32142298 DOI: 10.1021/acs.langmuir.0c00187] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
The dissipative particle dynamics (DPD) technique was employed to design multiple microfluidic devices for investigating the motion of bioparticles at low Reynolds numbers. A DPD in-house FORTRAN code was developed to simulate the trajectories of two microparticles in the presence of hydrodynamic and transverse deflecting force fields via considering interparticle interaction forces. The particle-particle interactions were described by using a simplified version of the Morse potential. The transverse deflecting force considered in this microfluidic application was the dielectrophoresis (DEP) force. Multiple microfluidic devices with different configurations of microelectrodes were numerically designed to investigate the dielectrophoretic behavior of bioparticles for their trajectories and the focusing of bioparticles into a single stream in the middle of the microchannel. The DPD simulation results were verified and validated against previously reported numerical and experimental works in the literature. The computationally designed microdevices were fabricated by employing standard lithographic techniques, and experiments were conducted via taking red blood cells as the representative bioparticles. The experimental results for the trajectories and focusing showed good agreement with the numerical results.
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Affiliation(s)
- Waqas Waheed
- Department of Mechanical Engineering, Khalifa University of Science and Technology, Abu Dhabi 127788, UAE
| | - Anas Alazzam
- Department of Mechanical Engineering, Khalifa University of Science and Technology, Abu Dhabi 127788, UAE
- System on Chip Center, Khalifa University of Science and Technology, Abu Dhabi 127788, UAE
| | - Ashraf N Al-Khateeb
- Department of Aerospace Engineering, Khalifa University of Science and Technology, Abu Dhabi 127788, UAE
| | - Eiyad Abu-Nada
- Department of Mechanical Engineering, Khalifa University of Science and Technology, Abu Dhabi 127788, UAE
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11
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Characterization of the Dielectrophoretic Response of Different Candida Strains Using 3D Carbon Microelectrodes. MICROMACHINES 2020; 11:mi11030255. [PMID: 32121163 PMCID: PMC7143313 DOI: 10.3390/mi11030255] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/03/2020] [Revised: 02/23/2020] [Accepted: 02/26/2020] [Indexed: 02/08/2023]
Abstract
Bloodstream infection with Candida fungal cells remains one of the most life-threatening complications among hospitalized patients around the world. Although most of the cases are still due to Candida albicans, the rising incidence of infections caused by other Candida strains that may not respond to traditional anti-fungal treatments merits the development of a method for species-specific isolation of Candida. To this end, here we present the characterization of the dielectrophoresis (DEP) response of Candida albicans, Candida tropicalis and Candida parapsilosis. We complement such characterization with a study of the Candida cells morphology. The Candida strains exhibited subtle differences in their morphology and dimensions. All the Candida strains exhibited positive DEP in the range 10-500 kHz, although the strength of the DEP response was different for each Candida strain at different frequencies. Only Candida tropicalis showed positive DEP at 750 kHz. The current results show potential for manipulation and enrichment of a specific Candida strain at specific DEP conditions towards aiding in the rapid identification of Candida strains to enable the effective and timely treatment of Candida infections.
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12
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Analysis of Bacteriophages with Insulator-Based Dielectrophoresis. MICROMACHINES 2019; 10:mi10070450. [PMID: 31277396 PMCID: PMC6680707 DOI: 10.3390/mi10070450] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/23/2019] [Revised: 06/28/2019] [Accepted: 06/30/2019] [Indexed: 02/07/2023]
Abstract
Bacterial viruses or phages have great potential in the medical and agricultural fields as alternatives to antibiotics to control nuisance populations of pathogenic bacteria. However, current analysis and purification protocols for phages tend to be resource intensive and have numbers of limitations, such as impacting phage viability. The present study explores the potential of employing the electrokinetic technique of insulator-based dielectrophoresis (iDEP) for virus assessment, separation and enrichment. In particular, the application of the parameter "trapping value" (Tv) is explored as a standardized iDEP signature for each phage species. The present study includes mathematical modeling with COMSOL Multiphysics and extensive experimentation. Three related, but genetically and structurally distinct, phages were studied: Salmonella enterica phage SPN3US, Pseudomonas aeruginosa phage ϕKZ and P. chlororaphis phage 201ϕ2-1. This is the first iDEP study on bacteriophages with large and complex virions and the results illustrate their virions can be successfully enriched with iDEP systems and still retain infectivity. In addition, our results indicate that characterization of the negative dielectrophoretic response of a phage in terms of Tv could be used for predicting individual virus behavior in iDEP systems. The findings reported here can contribute to the establishment of protocols to analyze, purify and/or enrich samples of known and unknown phages.
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13
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Ko C, Li D, Malekanfard A, Wang Y, Fu L, Xuan X. Electroosmotic flow of non‐Newtonian fluids in a constriction microchannel. Electrophoresis 2018; 40:1387-1394. [DOI: 10.1002/elps.201800315] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2018] [Revised: 10/04/2018] [Accepted: 10/04/2018] [Indexed: 11/06/2022]
Affiliation(s)
- Chien‐Hsuan Ko
- Department of Mechanical Engineering Clemson University Clemson SC USA
- Graduate Institute of Materials Engineering National Pingtung University of Science and Technology Taiwan
| | - Di Li
- Department of Mechanical Engineering Clemson University Clemson SC USA
| | | | - Yao‐Nan Wang
- Department of Vehicle Engineering National Pingtung University of Science and Technology Pingtung Taiwan
| | - Lung‐Ming Fu
- Graduate Institute of Materials Engineering National Pingtung University of Science and Technology Taiwan
- Department of Engineering Science National Cheng Kung University Tainan Taiwan
| | - Xiangchun Xuan
- Department of Mechanical Engineering Clemson University Clemson SC USA
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14
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Bonezzi J, Luitel T, Boika A. Electrokinetic Manipulation of Silver and Platinum Nanoparticles and Their Stochastic Electrochemical Detection. Anal Chem 2017; 89:8614-8619. [DOI: 10.1021/acs.analchem.7b02807] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Affiliation(s)
- Jason Bonezzi
- Department of Chemistry, The University of Akron, 190 East Buchtel Common, Akron, Ohio 44325, United States
| | - Tulashi Luitel
- Department of Chemistry, The University of Akron, 190 East Buchtel Common, Akron, Ohio 44325, United States
| | - Aliaksei Boika
- Department of Chemistry, The University of Akron, 190 East Buchtel Common, Akron, Ohio 44325, United States
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15
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Fernandez RE, Rohani A, Farmehini V, Swami NS. Review: Microbial analysis in dielectrophoretic microfluidic systems. Anal Chim Acta 2017; 966:11-33. [PMID: 28372723 PMCID: PMC5424535 DOI: 10.1016/j.aca.2017.02.024] [Citation(s) in RCA: 90] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2016] [Revised: 02/03/2017] [Accepted: 02/20/2017] [Indexed: 12/13/2022]
Abstract
Infections caused by various known and emerging pathogenic microorganisms, including antibiotic-resistant strains, are a major threat to global health and well-being. This highlights the urgent need for detection systems for microbial identification, quantification and characterization towards assessing infections, prescribing therapies and understanding the dynamic cellular modifications. Current state-of-the-art microbial detection systems exhibit a trade-off between sensitivity and assay time, which could be alleviated by selective and label-free microbial capture onto the sensor surface from dilute samples. AC electrokinetic methods, such as dielectrophoresis, enable frequency-selective capture of viable microbial cells and spores due to polarization based on their distinguishing size, shape and sub-cellular compositional characteristics, for downstream coupling to various detection modalities. Following elucidation of the polarization mechanisms that distinguish bacterial cells from each other, as well as from mammalian cells, this review compares the microfluidic platforms for dielectrophoretic manipulation of microbials and their coupling to various detection modalities, including immuno-capture, impedance measurement, Raman spectroscopy and nucleic acid amplification methods, as well as for phenotypic assessment of microbial viability and antibiotic susceptibility. Based on the urgent need within point-of-care diagnostics towards reducing assay times and enhancing capture of the target organism, as well as the emerging interest in isolating intact microbials based on their phenotype and subcellular features, we envision widespread adoption of these label-free and selective electrokinetic techniques.
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Affiliation(s)
- Renny E Fernandez
- Department of Electrical and Computer Engineering, University of Virginia, Charlottesville, VA 22904, USA
| | - Ali Rohani
- Department of Electrical and Computer Engineering, University of Virginia, Charlottesville, VA 22904, USA
| | - Vahid Farmehini
- Department of Electrical and Computer Engineering, University of Virginia, Charlottesville, VA 22904, USA
| | - Nathan S Swami
- Department of Electrical and Computer Engineering, University of Virginia, Charlottesville, VA 22904, USA.
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Siebman C, Velev OD, Slaveykova VI. Alternating Current-Dielectrophoresis Collection and Chaining of Phytoplankton on Chip: Comparison of Individual Species and Artificial Communities. BIOSENSORS 2017; 7:E4. [PMID: 28067772 PMCID: PMC5371777 DOI: 10.3390/bios7010004] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/06/2016] [Revised: 12/21/2016] [Accepted: 12/28/2016] [Indexed: 01/26/2023]
Abstract
The capability of alternating current (AC) dielectrophoresis (DEP) for on-chip capture and chaining of the three species representative of freshwater phytoplankton was evaluated. The effects of the AC field intensity, frequency and duration on the chaining efficiency and chain lengths of green alga Chlamydomonas reinhardtii, cyanobacterium Synechocystis sp. and diatom Cyclotella meneghiniana were characterized systematically. C. reinhardtii showed an increase of the chaining efficiency from 100 Hz to 500 kHz at all field intensities; C. meneghiniana presented a decrease of chaining efficiency from 100 Hz to 1 kHz followed by a significant increase from 1 kHz to 500 kHz, while Synechocystis sp. exhibited low chaining tendency at all frequencies and all field intensities. The experimentally-determined DEP response and cell alignment of each microorganism were in agreement with their effective polarizability. Mixtures of cells in equal proportion or 10-times excess of Synechocystis sp. showed important differences in terms of chaining efficiency and length of the chains compared with the results obtained when the cells were alone in suspension. While a constant degree of chaining was observed with the mixture of C. reinhardtii and C. meneghiniana, the presence of Synechocystis sp. in each mixture suppressed the formation of chains for the two other phytoplankton species. All of these results prove the potential of DEP to discriminate different phytoplankton species depending on their effective polarizability and to enable their manipulation, such as specific collection or separation in freshwater.
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Affiliation(s)
- Coralie Siebman
- Environmental Biogeochemistry and Ecotoxicology, Department F.-A. Forel for Environmental and Aquatic Sciences, Earth and Environmental Science, Faculty of Sciences, University of Geneva, 66 Boulevard Carl-Vogt, CH-1211 Genève 4, Switzerland.
| | - Orlin D Velev
- Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, NC 27695-7905, USA.
| | - Vera I Slaveykova
- Environmental Biogeochemistry and Ecotoxicology, Department F.-A. Forel for Environmental and Aquatic Sciences, Earth and Environmental Science, Faculty of Sciences, University of Geneva, 66 Boulevard Carl-Vogt, CH-1211 Genève 4, Switzerland.
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17
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Siebman C, Velev OD, Slaveykova VI. Two-Dimensional Algal Collection and Assembly by Combining AC-Dielectrophoresis with Fluorescence Detection for Contaminant-Induced Oxidative Stress Sensing. BIOSENSORS 2015; 5:319-36. [PMID: 26083806 PMCID: PMC4493552 DOI: 10.3390/bios5020319] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/13/2015] [Revised: 05/31/2015] [Accepted: 06/05/2015] [Indexed: 12/23/2022]
Abstract
An alternative current (AC) dielectrophoretic lab-on-chip setup was evaluated as a rapid tool of capture and assembly of microalga Chlamydomonas reinhardtii in two-dimensional (2D) close-packed arrays. An electric field of 100 V·cm⁻¹, 100 Hz applied for 30 min was found optimal to collect and assemble the algae into single-layer structures of closely packed cells without inducing cellular oxidative stress. Combined with oxidative stress specific staining and fluorescence microscopy detection, the capability of using the 2D whole-cell assembly on-chip to follow the reactive oxygen species (ROS) production and oxidative stress during short-term exposure to several environmental contaminants, including mercury, methylmercury, copper, copper oxide nanoparticles (CuO-NPs), and diuron was explored. The results showed significant increase of the cellular ROS when C. reinhardtii was exposed to high concentrations of methylmercury, CuO-NPs, and 10⁻⁵ M Cu. Overall, this study demonstrates the potential of combining AC-dielectrophoretically assembled two-dimensional algal structures with cell metabolic analysis using fluorescence staining, as a rapid analytical tool for probing the effect of contaminants in highly impacted environment.
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Affiliation(s)
- Coralie Siebman
- Environmental Biogeochemistry and Ecotoxicology, Institute F.-A. Forel, Earth and Environmental Science, Faculty of Sciences, University of Geneva, 10 route de Suisse, Versoix CH-1290, Switzerland.
| | - Orlin D Velev
- Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, NC 27695, USA.
| | - Vera I Slaveykova
- Environmental Biogeochemistry and Ecotoxicology, Institute F.-A. Forel, Earth and Environmental Science, Faculty of Sciences, University of Geneva, 10 route de Suisse, Versoix CH-1290, Switzerland.
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18
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Allahrabbi N, Chia YSM, Saifullah MSM, Lim KM, Yung LYL. A hybrid dielectrophoretic system for trapping of microorganisms from water. BIOMICROFLUIDICS 2015; 9:034110. [PMID: 26180567 PMCID: PMC4474952 DOI: 10.1063/1.4922276] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/20/2015] [Accepted: 05/28/2015] [Indexed: 05/24/2023]
Abstract
Assessment of the microbial safety of water resources is among the most critical issues in global water safety. As the current detection methods have limitations such as high cost and long process time, new detection techniques have transpired among which microfluidics is the most attractive alternative. Here, we show a novel hybrid dielectrophoretic (DEP) system to separate and detect two common waterborne pathogens, Escherichia coli (E. coli), a bacterium, and Cryptosporidium parvum (C. parvum), a protozoan parasite, from water. The hybrid DEP system integrates a chemical surface coating with a microfluidic device containing inter-digitated microelectrodes to impart positive dielectrophoresis for enhanced trapping of the cells. Trimethoxy(3,3,3-trifluoropropyl) silane, (3-aminopropyl)triethoxysilane, and polydiallyl dimethyl ammonium chloride (p-DADMAC) were used as surface coatings. Static cell adhesion tests showed that among these coatings, the p-DADMAC-coated glass surface provided the most effective cell adhesion for both the pathogens. This was attributed to the positively charged p-DADMAC-coated surface interacting electrostatically with the negatively charged cells suspended in water leading to increased cell trapping efficiency. The trapping efficiency of E. coli and C. parvum increased from 29.0% and 61.3% in an uncoated DEP system to 51.9% and 82.2% in the hybrid DEP system, respectively. The hybrid system improved the cell trapping by encouraging the formation of cell pearl-chaining. The increment in trapping efficiency in the hybrid DEP system was achieved at an optimal frequency of 1 MHz and voltage of 2.5 Vpp for C. parvum and 2 Vpp for E. coli, the latter is lower than 2.5 Vpp and 7 Vpp, respectively, utilized for obtaining similar efficiency in an uncoated DEP system.
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Affiliation(s)
| | - Yi Shi Michelle Chia
- Department of Chemical and Biomolecular Engineering, National University of Singapore , 10 Kent Ridge Crescent, Singapore 119260, Republic of Singapore
| | - Mohammad S M Saifullah
- Institute of Materials Research and Engineering , ASTAR (Agency for Science, Technology and Research), 3 Research Link, Singapore 117602, Republic of Singapore
| | - Kian-Meng Lim
- Department of Mechanical Engineering, National University of Singapore , 9 Engineering Drive 1, Singapore 117576, Republic of Singapore
| | - Lin Yue Lanry Yung
- Department of Chemical and Biomolecular Engineering, National University of Singapore , 10 Kent Ridge Crescent, Singapore 119260, Republic of Singapore
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19
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High resolution scanning electron microscopy of cells using dielectrophoresis. PLoS One 2014; 9:e104109. [PMID: 25089528 PMCID: PMC4121316 DOI: 10.1371/journal.pone.0104109] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2014] [Accepted: 07/08/2014] [Indexed: 12/02/2022] Open
Abstract
Ultrastructural analysis of cells can reveal valuable information about their morphological, physiological, and biochemical characteristics. Scanning electron microscopy (SEM) has been widely used to provide high-resolution images from the surface of biological samples. However, samples need to be dehydrated and coated with conductive materials for SEM imaging. Besides, immobilizing non-adherent cells during processing and analysis is challenging and requires complex fixation protocols. In this work, we developed a novel dielectrophoresis based microfluidic platform for interfacing non-adherent cells with high-resolution SEM at low vacuum mode. The system enables rapid immobilization and dehydration of samples without deposition of chemical residues over the cell surface. Moreover, it enables the on-chip chemical stimulation and fixation of immobilized cells with minimum dislodgement. These advantages were demonstrated for comparing the morphological changes of non-budding and budding yeast cells following Lyticase treatment.
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Fatoyinbo HO, McDonnell MC, Hughes MP. Dielectrophoretic sample preparation for environmental monitoring of microorganisms: Soil particle removal. BIOMICROFLUIDICS 2014; 8:044115. [PMID: 25379100 PMCID: PMC4189292 DOI: 10.1063/1.4892036] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/02/2014] [Accepted: 07/22/2014] [Indexed: 05/04/2023]
Abstract
Detection of pathogens from environmental samples is often hampered by sensors interacting with environmental particles such as soot, pollen, or environmental dust such as soil or clay. These particles may be of similar size to the target bacterium, preventing removal by filtration, but may non-specifically bind to sensor surfaces, fouling them and causing artefactual results. In this paper, we report the selective manipulation of soil particles using an AC electrokinetic microfluidic system. Four heterogeneous soil samples (smectic clay, kaolinitic clay, peaty loam, and sandy loam) were characterised using dielectrophoresis to identify the electrical difference to a target organism. A flow-cell device was then constructed to evaluate dielectrophoretic separation of bacteria and clay in a continous flow through mode. The average separation efficiency of the system across all soil types was found to be 68.7% with a maximal separation efficiency for kaolinitic clay at 87.6%. This represents the first attempt to separate soil particles from bacteria using dielectrophoresis and indicate that the technique shows significant promise; with appropriate system optimisation, we believe that this preliminary study represents an opportunity to develop a simple yet highly effective sample processing system.
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Affiliation(s)
- Henry O Fatoyinbo
- Centre for Biomedical Engineering, Department of Mechanical Engineering Sciences, University of Surrey , Guildford, Surrey GU2 7XH, United Kingdom
| | | | - Michael P Hughes
- Centre for Biomedical Engineering, Department of Mechanical Engineering Sciences, University of Surrey , Guildford, Surrey GU2 7XH, United Kingdom
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Gallo-Villanueva RC, Sano MB, Lapizco-Encinas BH, Davalos RV. Joule heating effects on particle immobilization in insulator-based dielectrophoretic devices. Electrophoresis 2014; 35:352-61. [PMID: 24002905 PMCID: PMC4114348 DOI: 10.1002/elps.201300171] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2013] [Revised: 07/31/2013] [Accepted: 08/01/2013] [Indexed: 11/10/2022]
Abstract
In this work, the temperature effects due to Joule heating obtained by application of a direct current electric potential were investigated for a microchannel with cylindrical insulating posts employed for insulator-based dielectrophoresis. The conductivity of the suspending medium, the local electric field, and the gradient of the squared electric field, which directly affect the magnitude of the dielectrophoretic force exerted on particles, were computationally simulated employing COMSOL Multiphysics. It was observed that a temperature gradient is formed along the microchannel, which redistributes the conductivity of the suspending medium leading to an increase of the dielectrophoretic force toward the inlet of the channel while decreasing toward the outlet. Experimental results are in good agreement with simulations on the particle-trapping zones anticipated. This study demonstrates the importance of considering Joule heating effects when designing insulator-based dielectrophoresis systems.
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Affiliation(s)
| | - Michael B. Sano
- School of Biomedical Engineering and Sciences, Virginia Tech
– Wake Forest University, Blacksburg, VA, USA
| | - Blanca H. Lapizco-Encinas
- Microscale Bioseparations Laboratory and Department of Chemical and
Biomedical Engineering, Rochester Institute of Technology, Rochester, NY, USA
| | - Rafael V. Davalos
- School of Biomedical Engineering and Sciences, Virginia Tech
– Wake Forest University, Blacksburg, VA, USA
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22
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Dubose J, Lu X, Patel S, Qian S, Woo Joo S, Xuan X. Microfluidic electrical sorting of particles based on shape in a spiral microchannel. BIOMICROFLUIDICS 2014; 8:014101. [PMID: 24753722 PMCID: PMC3977798 DOI: 10.1063/1.4862355] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/02/2013] [Accepted: 01/06/2014] [Indexed: 05/11/2023]
Abstract
Shape is an intrinsic marker of cell cycle, an important factor for identifying a bioparticle, and also a useful indicator of cell state for disease diagnostics. Therefore, shape can be a specific marker in label-free particle and cell separation for various chemical and biological applications. We demonstrate in this work a continuous-flow electrical sorting of spherical and peanut-shaped particles of similar volumes in an asymmetric double-spiral microchannel. It exploits curvature-induced dielectrophoresis to focus particles to a tight stream in the first spiral without any sheath flow and subsequently displace them to shape-dependent flow paths in the second spiral without any external force. We also develop a numerical model to simulate and understand this shape-based particle sorting in spiral microchannels. The predicted particle trajectories agree qualitatively with the experimental observation.
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Affiliation(s)
- John Dubose
- Department of Mechanical Engineering, Clemson University, Clemson, South Carolina 29634-0921, USA
| | - Xinyu Lu
- Department of Mechanical Engineering, Clemson University, Clemson, South Carolina 29634-0921, USA
| | - Saurin Patel
- Department of Mechanical Engineering, Clemson University, Clemson, South Carolina 29634-0921, USA
| | - Shizhi Qian
- Institute of Micro/Nanotechnology, Old Dominion University, Norfolk, Virginia 23529, USA
| | - Sang Woo Joo
- School of Mechanical Engineering, Yeungnam University, Gyongsan 712-719, South Korea
| | - Xiangchun Xuan
- Department of Mechanical Engineering, Clemson University, Clemson, South Carolina 29634-0921, USA
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23
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Suscillon C, Velev OD, Slaveykova VI. Alternating current-dielectrophoresis driven on-chip collection and chaining of green microalgae in freshwaters. BIOMICROFLUIDICS 2013; 7:24109. [PMID: 24404014 PMCID: PMC3643985 DOI: 10.1063/1.4801870] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/18/2013] [Accepted: 04/01/2013] [Indexed: 05/03/2023]
Abstract
The capability of the AC dielectrophoresis (DEP) for on-chip capture and chaining of microalgae suspended in freshwaters was evaluated. The effects of freshwater composition as well as the electric field voltage, frequency, and duration, on the dielectrophoretic response of microalga Chlamydomonas reinhardtii were characterized systematically. Highest efficiency of cell alignment in one-dimensional arrays, determined by the percentage of cells in chain and the chain length, was obtained at AC-field of 20 V mm(-1) and 1 kHz applied for 600 s. The DEP response and cell alignment of C. reinhardtii in water sampled from lake, pond, and river, as well as model media were affected by the chemical composition of the media. In the model media, the efficiency of DEP chaining was negatively correlated to the conductivity of the cell suspensions, being higher in suspensions with low conductivity. The cells suspended in freshwaters, however, showed anomalously high chaining at long exposure times. High concentrations of nitrate and dissolved organic matter decrease cell chaining efficiency, while phosphate and citrate concentrations increase it and favor formation of longer chains. Importantly, the application of AC-field had no effect on algal autofluorescence, cell membrane damage, or oxidative stress damages in C. reinhardtii.
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Affiliation(s)
- Coralie Suscillon
- Aquatic Biogeochemistry and Ecotoxicology, Institute F.-A. Forel, Earth and Environmental Science, Faculty of Sciences, University of Geneva, 10, route de Suisse, CH-1290 Versoix, Switzerland
| | - Orlin D Velev
- Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, North Carolina 27695-7905, USA
| | - Vera I Slaveykova
- Aquatic Biogeochemistry and Ecotoxicology, Institute F.-A. Forel, Earth and Environmental Science, Faculty of Sciences, University of Geneva, 10, route de Suisse, CH-1290 Versoix, Switzerland
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24
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Lopez-de la Fuente MS, Moncada-Hernandez H, Perez-Gonzalez VH, Lapizco-Encinas BH, Martinez-Chapa SO. An electric stimulation system for electrokinetic particle manipulation in microfluidic devices. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2013; 84:035103. [PMID: 23556848 DOI: 10.1063/1.4793559] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Microfluidic devices have grown significantly in the number of applications. Microfabrication techniques have evolved considerably; however, electric stimulation systems for microdevices have not advanced at the same pace. Electric stimulation of micro-fluidic devices is an important element in particle manipulation research. A flexible stimulation instrument is desired to perform configurable, repeatable, automated, and reliable experiments by allowing users to select the stimulation parameters. The instrument presented here is a configurable and programmable stimulation system for electrokinetic-driven microfluidic devices; it consists of a processor, a memory system, and a user interface to deliver several types of waveforms and stimulation patterns. It has been designed to be a flexible, highly configurable, low power instrument capable of delivering sine, triangle, and sawtooth waveforms with one single frequency or two superimposed frequencies ranging from 0.01 Hz to 40 kHz, and an output voltage of up to 30 Vpp. A specific stimulation pattern can be delivered over a single time period or as a sequence of different signals for different time periods. This stimulation system can be applied as a research tool where manipulation of particles suspended in liquid media is involved, such as biology, medicine, environment, embryology, and genetics. This system has the potential to lead to new schemes for laboratory procedures by allowing application specific and user defined electric stimulation. The development of this device is a step towards portable and programmable instrumentation for electric stimulation on electrokinetic-based microfluidic devices, which are meant to be integrated with lab-on-a-chip devices.
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Affiliation(s)
- M S Lopez-de la Fuente
- Electrical and Computer Engineering, Tecnologico de Monterrey, Nuevo Leon 64849, Mexico.
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