1
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Romero Deza AA, Schaumburg F, Berli CLA. Valveless On-Chip Aliquoting for Molecular Diagnosis. MICROMACHINES 2023; 14:1425. [PMID: 37512736 PMCID: PMC10386703 DOI: 10.3390/mi14071425] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/25/2023] [Revised: 07/09/2023] [Accepted: 07/13/2023] [Indexed: 07/30/2023]
Abstract
The detection of nucleic acids as specific markers of infectious diseases is commonly implemented in molecular biology laboratories. The translation of these benchtop assays to a lab-on-a-chip format demands huge efforts of integration and automation. The present work is motivated by a strong requirement often posed by molecular assays that combine isothermal amplification and CRISPR/Cas-based detection: after amplification, a 2-8 microliter aliquot of the reaction products must be taken for the subsequent reaction. In order to fulfill this technical problem, we have designed and prototyped a microfluidic device that is able to meter and aliquot in the required range during the stepped assay. The operation is achieved by integrating a porous material that retains the desired amount of liquid after removing the excess reaction products, an innovative solution that avoids valving and external actuation. The prototypes were calibrated and experimentally tested to demonstrate the overall performance (general fluidics, metering, aliquoting, mixing and reaction). The proposed aliquoting method is fully compatible with additional functions, such as sample concentration or reagent storage, and could be further employed in alternative applications beyond molecular diagnosis.
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Affiliation(s)
| | - Federico Schaumburg
- Predio CCT CONICET Santa Fe, INTEC (Universidad Nacional del Litoral-CONICET), RN 168, Santa Fe 3000, Argentina
| | - Claudio L A Berli
- Predio CCT CONICET Santa Fe, INTEC (Universidad Nacional del Litoral-CONICET), RN 168, Santa Fe 3000, Argentina
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2
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Vasina M, Kovar D, Damborsky J, Ding Y, Yang T, deMello A, Mazurenko S, Stavrakis S, Prokop Z. In-depth analysis of biocatalysts by microfluidics: An emerging source of data for machine learning. Biotechnol Adv 2023; 66:108171. [PMID: 37150331 DOI: 10.1016/j.biotechadv.2023.108171] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2023] [Revised: 05/04/2023] [Accepted: 05/04/2023] [Indexed: 05/09/2023]
Abstract
Nowadays, the vastly increasing demand for novel biotechnological products is supported by the continuous development of biocatalytic applications which provide sustainable green alternatives to chemical processes. The success of a biocatalytic application is critically dependent on how quickly we can identify and characterize enzyme variants fitting the conditions of industrial processes. While miniaturization and parallelization have dramatically increased the throughput of next-generation sequencing systems, the subsequent characterization of the obtained candidates is still a limiting process in identifying the desired biocatalysts. Only a few commercial microfluidic systems for enzyme analysis are currently available, and the transformation of numerous published prototypes into commercial platforms is still to be streamlined. This review presents the state-of-the-art, recent trends, and perspectives in applying microfluidic tools in the functional and structural analysis of biocatalysts. We discuss the advantages and disadvantages of available technologies, their reproducibility and robustness, and readiness for routine laboratory use. We also highlight the unexplored potential of microfluidics to leverage the power of machine learning for biocatalyst development.
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Affiliation(s)
- Michal Vasina
- Loschmidt Laboratories, Department of Experimental Biology and RECETOX, Faculty of Science, Masaryk University, 602 00 Brno, Czech Republic; International Clinical Research Centre, St. Anne's University Hospital, 656 91 Brno, Czech Republic
| | - David Kovar
- Loschmidt Laboratories, Department of Experimental Biology and RECETOX, Faculty of Science, Masaryk University, 602 00 Brno, Czech Republic; International Clinical Research Centre, St. Anne's University Hospital, 656 91 Brno, Czech Republic
| | - Jiri Damborsky
- Loschmidt Laboratories, Department of Experimental Biology and RECETOX, Faculty of Science, Masaryk University, 602 00 Brno, Czech Republic; International Clinical Research Centre, St. Anne's University Hospital, 656 91 Brno, Czech Republic
| | - Yun Ding
- Institute for Chemical and Bioengineering, ETH Zürich, 8093 Zürich, Switzerland
| | - Tianjin Yang
- Institute for Chemical and Bioengineering, ETH Zürich, 8093 Zürich, Switzerland; Department of Biochemistry, University of Zurich, 8057 Zurich, Switzerland
| | - Andrew deMello
- Institute for Chemical and Bioengineering, ETH Zürich, 8093 Zürich, Switzerland
| | - Stanislav Mazurenko
- Loschmidt Laboratories, Department of Experimental Biology and RECETOX, Faculty of Science, Masaryk University, 602 00 Brno, Czech Republic; International Clinical Research Centre, St. Anne's University Hospital, 656 91 Brno, Czech Republic.
| | - Stavros Stavrakis
- Institute for Chemical and Bioengineering, ETH Zürich, 8093 Zürich, Switzerland.
| | - Zbynek Prokop
- Loschmidt Laboratories, Department of Experimental Biology and RECETOX, Faculty of Science, Masaryk University, 602 00 Brno, Czech Republic; International Clinical Research Centre, St. Anne's University Hospital, 656 91 Brno, Czech Republic.
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3
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Huang C, Guo F, Wang H, Olivares J, Dalton Iii J, Belyanina O, Wattam AR, Cucinell CA, Dickerman AW, Qin QM, Han A, de Figueiredo P. An automated system for interrogating the evolution of microbial endosymbiosis. LAB ON A CHIP 2023; 23:671-683. [PMID: 36227118 DOI: 10.1039/d2lc00602b] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Inter-kingdom endosymbiotic interactions between bacteria and eukaryotic cells are critical to human health and disease. However, the molecular mechanisms that drive the emergence of endosymbiosis remain obscure. Here, we describe the development of a microfluidic system, named SEER (S̲ystem for the E̲volution of E̲ndosymbiotic R̲elationships), that automates the evolutionary selection of bacteria with enhanced intracellular survival and persistence within host cells, hallmarks of endosymbiosis. Using this system, we show that a laboratory strain of Escherichia coli that initially possessed limited abilities to survive within host cells, when subjected to SEER selection, rapidly evolved to display a 55-fold enhancement in intracellular survival. Notably, molecular dissection of the evolved strains revealed that a single-point mutation in a flexible loop of CpxR, a gene regulator that controls bacterial stress responses, substantially contributed to this intracellular survival. Taken together, these results establish SEER as the first microfluidic system for investigating the evolution of endosymbiosis, show the importance of CpxR in endosymbiosis, and set the stage for evolving bespoke inter-kingdom endosymbiotic systems with novel or emergent properties.
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Affiliation(s)
- Can Huang
- Department of Electrical and Computer Engineering, Texas A&M University, College Station, TX 77843, USA
| | - Fengguang Guo
- Department of Microbial Pathogenesis and Immunology, Texas A&M Health Science Center, Bryan, TX 77843, USA.
| | - Han Wang
- Department of Biomedical Engineering, School of Medicine, Tsinghua University, 100084, Beijing, China
| | - Jasmine Olivares
- Department of Microbial Pathogenesis and Immunology, Texas A&M Health Science Center, Bryan, TX 77843, USA.
| | - James Dalton Iii
- Department of Microbial Pathogenesis and Immunology, Texas A&M Health Science Center, Bryan, TX 77843, USA.
| | - Olga Belyanina
- Department of Microbial Pathogenesis and Immunology, Texas A&M Health Science Center, Bryan, TX 77843, USA.
| | - Alice R Wattam
- Biocomplexity Institute and Initiative, University of Virginia, Charlottesville, VA 22904, USA
| | - Clark A Cucinell
- Biocomplexity Institute and Initiative, University of Virginia, Charlottesville, VA 22904, USA
| | - Allan W Dickerman
- Biocomplexity Institute and Initiative, University of Virginia, Charlottesville, VA 22904, USA
| | - Qing-Ming Qin
- Department of Microbial Pathogenesis and Immunology, Texas A&M Health Science Center, Bryan, TX 77843, USA.
| | - Arum Han
- Department of Electrical and Computer Engineering, Texas A&M University, College Station, TX 77843, USA
- Department of Biomedical Engineering, Texas A&M University, College Station, TX 77843, USA
- Artie McFerrin Department of Chemical Engineering, Texas A&M University, College Station, TX, 77843, USA
| | - Paul de Figueiredo
- Department of Microbial Pathogenesis and Immunology, Texas A&M Health Science Center, Bryan, TX 77843, USA.
- Department of Veterinary Pathobiology, Texas A&M University, College Station, TX 77843, USA
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4
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Abe T, Oh-hara S, Ukita Y. Integration of reinforcement learning to realize functional variability of microfluidic systems. BIOMICROFLUIDICS 2022; 16:024106. [PMID: 35356131 PMCID: PMC8934189 DOI: 10.1063/5.0087079] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/01/2022] [Accepted: 03/04/2022] [Indexed: 05/12/2023]
Abstract
In this article, we present a proof-of-concept for microfluidic systems with high functional variability using reinforcement learning. By mathematically defining the objective of tasks, we demonstrate that the system can autonomously learn to behave according to its objectives. We applied Q-learning to a peristaltic micropump and showed that two different tasks can be performed on the same platform: adjusting the flow rate of the pump and manipulating the position of the particles. First, we performed typical micropumping with flow rate control. In this task, the system is rewarded according to the deviation between the average flow rate generated by the micropump and the target value. Therefore, the objective of the system is to maintain the target flow rate via an operation of the pump. Next, we demonstrate the micromanipulation of a small object (microbead) on the same platform. The objective was to manipulate the microbead position to the target area, and the system was rewarded for the success of the task. These results confirmed that the system learned to control the flow rate and manipulate the microbead to any randomly chosen target position. In particular, the manipulation technique is a new technology that does not require the use of structures such as wells or weirs. Therefore, this concept not only adds flexibility to the system but also contributes to the development of novel control methods to realize highly versatile microfluidic systems.
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Affiliation(s)
- Takaaki Abe
- Department of Engineering, Integrated Graduate School of Medicine, Engineering, and Agricultural Sciences, University of Yamanashi, 4-3-11 Takeda, Kofu 400-8510, Japan
| | - Shinsuke Oh-hara
- Graduate Faculty of Interdisciplinary Research, University of Yamanashi, 4-3-11 Takeda, Kofu 400-8510, Japan
| | - Yoshiaki Ukita
- Graduate Faculty of Interdisciplinary Research, University of Yamanashi, 4-3-11 Takeda, Kofu 400-8510, Japan
- Author to whom correspondence should be addressed:
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5
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Battat S, Weitz DA, Whitesides GM. An outlook on microfluidics: the promise and the challenge. LAB ON A CHIP 2022; 22:530-536. [PMID: 35048918 DOI: 10.1039/d1lc00731a] [Citation(s) in RCA: 73] [Impact Index Per Article: 36.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
This perspective considers ways in which the field of microfluidics can increase its impact by improving existing technologies and enabling new functionalities. We highlight applications where microfluidics has made or can make important contributions, including diagnostics, food safety, and the production of materials. The success of microfluidics assumes several forms, including fundamental innovations in fluid mechanics that enable the precise manipulation of fluids at small scales and the development of portable microfluidic chips for commercial purposes. We identify outstanding technical challenges whose resolution could increase the accessibility of microfluidics to users with both scientific and non-technical backgrounds. They include the simplification of procedures for sample preparation, the identification of materials for the production of microfluidic devices in both laboratory and commercial settings, and the replacement of auxiliary equipment with automated components for the operation of microfluidic devices.
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Affiliation(s)
- Sarah Battat
- John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts 02138, USA.
| | - David A Weitz
- John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts 02138, USA.
- Department of Physics, Harvard University, Cambridge, Massachusetts 02138, USA
| | - George M Whitesides
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138, USA.
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6
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Shao C, Chi J, Shang L, Fan Q, Ye F. Droplet microfluidics-based biomedical microcarriers. Acta Biomater 2022; 138:21-33. [PMID: 34718181 DOI: 10.1016/j.actbio.2021.10.037] [Citation(s) in RCA: 29] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2021] [Revised: 10/20/2021] [Accepted: 10/21/2021] [Indexed: 12/21/2022]
Abstract
Droplet microfluidic technology provides a new platform for controllable generation of microdroplets and droplet-derived materials. In particular, because of the ability in high-throughput production and accurate control of the size, structure, and function of these materials, droplet microfluidics presents unique advantages in the preparation of functional microcarriers, i.e., microsized liquid containers or solid particles that serve as substrates of biomolecules or cells. These microcarriers could be extensively applied in the areas of cell culture, tissue engineering, and drug delivery. In this review, we focus on the fabrication of microcarriers from droplet microfluidics, and discuss their applications in the biomedical field. We start with the basic principle of droplet microfluidics, including droplet generation regimes and its control methods. We then introduce the fabrication of biomedical microcarriers based on single, double, and multiple emulsion droplets, and emphasize the various applications of microcarriers in biomedical field, especially in 3D cell culture, drug development and biomedical detection. Finally, we conclude this review by discussing the limitations and challenges of droplet microfluidics in preparing microcarriers. STATEMENT OF SIGNIFICANCE: Because of its precise control and high throughput, droplet microfluidics has been employed to generate functional microcarriers, which have been widely used in the areas of drug development, tissue engineering, and regenerative medicine. This review is significant because it emphasizes recent progress in research on droplet microfluidics in the preparation and application of biomedical microcarriers. In addition, this review suggests research directions for the future development of biomedical microcarriers based on droplet microfluidics by presenting existing shortcomings and challenges.
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7
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Abstract
Lab-on-a-chip devices leverage microfluidic technologies to enable chemical and biological processes at small scales. However, existing microfluidic channel networks are typically designed for the implementation of a single function or a well-defined protocol and do not allow the flexibility and real-time experimental decision-making essential to many scientific applications. In this Perspective, we highlight that reconfigurability and programmability of microfluidic platforms can support new functionalities that are beyond the reach of current lab-on-a-chip systems. We describe the ideal fully reconfigurable microfluidic device that can change its shape and function dynamically, which would allow researchers to tune a microscale experiment with the capacity to make real-time decisions. We review existing technologies that can dynamically control microscale flows, suggest additional physical mechanisms that could be leveraged towards the goal of reconfigurable microfluidics and highlight the importance of these efforts for the broad scientific community.
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8
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Kerk YJ, Jameel A, Xing X, Zhang C. Recent advances of integrated microfluidic suspension cell culture system. ENGINEERING BIOLOGY 2021; 5:103-119. [PMID: 36970555 PMCID: PMC9996741 DOI: 10.1049/enb2.12015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2021] [Revised: 09/29/2021] [Accepted: 09/30/2021] [Indexed: 11/19/2022] Open
Abstract
Microfluidic devices with superior microscale fluid manipulation ability and large integration flexibility offer great advantages of high throughput, parallelisation and multifunctional automation. Such features have been extensively utilised to facilitate cell culture processes such as cell capturing and culturing under controllable and monitored conditions for cell-based assays. Incorporating functional components and microfabricated configurations offered different levels of fluid control and cell manipulation strategies to meet diverse culture demands. This review will discuss the advances of single-phase flow and droplet-based integrated microfluidic suspension cell culture systems and their applications for accelerated bioprocess development, high-throughput cell selection, drug screening and scientific research to insight cell biology. Challenges and future prospects for this dynamically developing field are also highlighted.
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Affiliation(s)
- Yi Jing Kerk
- Institute of Biochemical EngineeringDepartment of Chemical Engineering, Tsinghua UniversityBeijingChina
| | - Aysha Jameel
- Institute of Biochemical EngineeringDepartment of Chemical Engineering, Tsinghua UniversityBeijingChina
- MOE Key Laboratory of Industrial BiocatalysisDepartment of Chemical Engineering, Tsinghua UniversityBeijingChina
| | - Xin‐Hui Xing
- Institute of Biochemical EngineeringDepartment of Chemical Engineering, Tsinghua UniversityBeijingChina
- MOE Key Laboratory of Industrial BiocatalysisDepartment of Chemical Engineering, Tsinghua UniversityBeijingChina
- Center for Synthetic and Systems BiologyTsinghua UniversityBeijingChina
| | - Chong Zhang
- Institute of Biochemical EngineeringDepartment of Chemical Engineering, Tsinghua UniversityBeijingChina
- MOE Key Laboratory of Industrial BiocatalysisDepartment of Chemical Engineering, Tsinghua UniversityBeijingChina
- Center for Synthetic and Systems BiologyTsinghua UniversityBeijingChina
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9
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Abe T, Oh-hara S, Ukita Y. Adoption of reinforcement learning for the intelligent control of a microfluidic peristaltic pump. BIOMICROFLUIDICS 2021; 15:034101. [PMID: 33986901 PMCID: PMC8106535 DOI: 10.1063/5.0032377] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/07/2020] [Accepted: 04/22/2021] [Indexed: 05/26/2023]
Abstract
We herein report a study on the intelligent control of microfluidic systems using reinforcement learning. Integrated microvalves are utilized to realize a variety of microfluidic functional modules, such as switching of flow pass, micropumping, and micromixing. The application of artificial intelligence to control microvalves can potentially contribute to the expansion of the versatility of microfluidic systems. As a preliminary attempt toward this motivation, we investigated the application of a reinforcement learning algorithm to microperistaltic pumps. First, we assumed a Markov property for the operation of diaphragms in the microperistaltic pump. Thereafter, components of the Markov decision process were defined for adaptation to the micropump. To acquire the pumping sequence, which maximizes the flow rate, the reward was defined as the obtained flow rate in a state transition of the microvalves. The present system successfully empirically determines the optimal sequence, which considers the physical characteristics of the components of the system that the authors did not recognize. Therefore, it was proved that reinforcement learning could be applied to microperistaltic pumps and is promising for the operation of larger and more complex microsystems.
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Affiliation(s)
- Takaaki Abe
- Department of Engineering, Integrated Graduate School of Medicine, Engineering, and Agricultural Sciences, University of Yamanashi, 4-3-11 Takeda, Kofu 400-8510, Japan
| | - Shinsuke Oh-hara
- Graduate Faculty of Interdisciplinary Research, University of Yamanashi, 4-3-11 Takeda, Kofu 400-8510, Japan
| | - Yoshiaki Ukita
- Graduate Faculty of Interdisciplinary Research, University of Yamanashi, 4-3-11 Takeda, Kofu 400-8510, Japan
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10
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Affiliation(s)
- Martin Mayer
- Wilhelm-Ostwald-Institut für Physikalische und Theoretische Chemie, Universität Leipzig, Linnéstraße 2, 04103 Leipzig, Germany
| | - Knut R. Asmis
- Wilhelm-Ostwald-Institut für Physikalische und Theoretische Chemie, Universität Leipzig, Linnéstraße 2, 04103 Leipzig, Germany
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11
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Han SJ, Kwon S, Kim KS. Challenges of applying multicellular tumor spheroids in preclinical phase. Cancer Cell Int 2021; 21:152. [PMID: 33663530 PMCID: PMC7934264 DOI: 10.1186/s12935-021-01853-8] [Citation(s) in RCA: 157] [Impact Index Per Article: 52.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2020] [Accepted: 02/24/2021] [Indexed: 02/07/2023] Open
Abstract
The three-dimensional (3D) multicellular tumor spheroids (MCTs) model is becoming an essential tool in cancer research as it expresses an intermediate complexity between 2D monolayer models and in vivo solid tumors. MCTs closely resemble in vivo solid tumors in many aspects, such as the heterogeneous architecture, internal gradients of signaling factors, nutrients, and oxygenation. MCTs have growth kinetics similar to those of in vivo tumors, and the cells in spheroid mimic the physical interaction of the tumors, such as cell-to-cell and cell-to-extracellular matrix interactions. These similarities provide great potential for studying the biological properties of tumors and a promising platform for drug screening and therapeutic efficacy evaluation. However, MCTs are not well adopted as preclinical tools for studying tumor behavior and therapeutic efficacy up to now. In this review, we addressed the challenges with MCTs application and discussed various efforts to overcome the challenges.
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Affiliation(s)
- Se Jik Han
- Department of Biomedical Engineering, Graduate School, Kyung Hee University, Seoul, 02447, Korea
- Department of Biomedical Engineering, College of Medicine, Kyung Hee University, Seoul, 02447, Korea
| | - Sangwoo Kwon
- Department of Biomedical Engineering, College of Medicine, Kyung Hee University, Seoul, 02447, Korea
| | - Kyung Sook Kim
- Department of Biomedical Engineering, College of Medicine, Kyung Hee University, Seoul, 02447, Korea.
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12
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Taylor DP, Kaigala GV. Reconfigurable microfluidics: real-time shaping of virtual channels through hydrodynamic forces. LAB ON A CHIP 2020; 20:1720-1728. [PMID: 32253402 DOI: 10.1039/d0lc00197j] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
To break the current paradigm in microfluidics that directly links device design to functionality, we introduce microfluidic "virtual channels" that can be dynamically shaped in real-time. A virtual channel refers to a flow path within a microfluidic flow cell, guiding an injected reagent along a user-defined trajectory solely by hydrodynamic forces. Virtual channels dynamically reproduce key microfluidic functionality: directed transport of minute volumes of liquid, splitting, merging and mixing of flows. Virtual channels can be formed directly on standard biological substrates, which we demonstrate by sequential immunodetection at arrays of individual reaction sites on a glass slide and by alternating between local and global processing of surface-adherent cell-block sections. This approach is simple, versatile and generic enough to form the basis of a new class of microfluidic techniques.
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Affiliation(s)
- David P Taylor
- Laboratory of Microsystems LMIS4, Ecole Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland
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13
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Abstract
Microfluidic devices developed over the past decade feature greater intricacy, increased performance requirements, new materials, and innovative fabrication methods. Consequentially, new algorithmic and design approaches have been developed to introduce optimization and computer-aided design to microfluidic circuits: from conceptualization to specification, synthesis, realization, and refinement. The field includes the development of new description languages, optimization methods, benchmarks, and integrated design tools. Here, recent advancements are reviewed in the computer-aided design of flow-, droplet-, and paper-based microfluidics. A case study of the design of resistive microfluidic networks is discussed in detail. The review concludes with perspectives on the future of computer-aided microfluidics design, including the introduction of cloud computing, machine learning, new ideation processes, and hybrid optimization.
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Affiliation(s)
- Elishai Ezra Tsur
- Neuro-Biomorphic Engineering Lab (NBEL), Department of Mathematics and Computer Science, The Open University of Israel, Ra'anana 4353701, Israel;
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14
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Mathur L, Ballinger M, Utharala R, Merten CA. Microfluidics as an Enabling Technology for Personalized Cancer Therapy. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2020; 16:e1904321. [PMID: 31747127 DOI: 10.1002/smll.201904321] [Citation(s) in RCA: 45] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/05/2019] [Revised: 10/14/2019] [Indexed: 05/26/2023]
Abstract
Tailoring patient-specific treatments for cancer is necessary in order to achieve optimal results but requires new diagnostic approaches at affordable prices. Microfluidics has immense potential to provide solutions for this, as it enables the processing of samples that are not available in large quantities (e.g., cells from patient biopsies), is cost efficient, provides a high level of automation, and allows the set-up of complex models for cancer studies. In this review, individual solutions in the fields of genetics, circulating tumor cell monitoring, biomarker analysis, phenotypic drug sensitivity tests, and systems providing controlled environments for disease modeling are discussed. An overview on how these early stage achievements can be combined or developed further is showcased, and the required translational steps before microfluidics becomes a routine tool for clinical applications are critically discussed.
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Affiliation(s)
- Lukas Mathur
- European Molecular Biology Laboratory (EMBL), Genome Biology Unit, Meyerhofstrasse 1, 69117, Heidelberg, Germany
| | - Martine Ballinger
- European Molecular Biology Laboratory (EMBL), Genome Biology Unit, Meyerhofstrasse 1, 69117, Heidelberg, Germany
| | - Ramesh Utharala
- European Molecular Biology Laboratory (EMBL), Genome Biology Unit, Meyerhofstrasse 1, 69117, Heidelberg, Germany
| | - Christoph A Merten
- European Molecular Biology Laboratory (EMBL), Genome Biology Unit, Meyerhofstrasse 1, 69117, Heidelberg, Germany
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15
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Hamdani HEL, Amane MEL, Duhayon C. Preparation, spectral, structural, thermal and anticancer molecular docking studies of bis-(theophyllinato)-tetraaquocobalt(II) complex. J Mol Struct 2019. [DOI: 10.1016/j.molstruc.2019.04.063] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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16
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Aksoy B, Besse N, Boom RJ, Hoogenberg BJ, Blom M, Shea H. Latchable microfluidic valve arrays based on shape memory polymer actuators. LAB ON A CHIP 2019; 19:608-617. [PMID: 30662992 DOI: 10.1039/c8lc01024b] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
We report arrays of latching microfluidic valves based on shape memory polymers (SMPs), and show their applications as reagent mixers and as peristaltic pumps. The valve design takes advantage of the SMP's multiple stable shapes and over a hundred-fold stiffness change with temperature to enable a) permanent zero-power latching in either open or closed positions (>15 h), as well as b) extended cyclic operation (>3000 cycles). The moving element in the valves consists of a tri-layer with a 50 μm thick central SMP layer, 25 μm thick patterned carbon-silicone (CB/PDMS) heaters underneath, and a 38 μm thick styrene ethylene butylene styrene (SEBS) impermeable film on top. Each valve of the array is individually addressable by synchronizing its integrated local Joule heating with a single external pressure supply. This architecture significantly reduces the device footprint and eliminates the need for multiplexing in microfluidic large scale integration (mLSI) systems.
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Affiliation(s)
- Bekir Aksoy
- Soft Transducers Laboratory (LMTS), Ecole Polytechnique Fédérale de Lausanne (EPFL), 2000 Neuchâtel, Switzerland.
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17
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Worms on a Chip. Bioanalysis 2019. [DOI: 10.1007/978-981-13-6229-3_6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022] Open
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18
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Sinha N, Subedi N, Tel J. Integrating Immunology and Microfluidics for Single Immune Cell Analysis. Front Immunol 2018; 9:2373. [PMID: 30459757 PMCID: PMC6232771 DOI: 10.3389/fimmu.2018.02373] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2018] [Accepted: 09/24/2018] [Indexed: 12/16/2022] Open
Abstract
The field of immunoengineering aims to develop novel therapies and modern vaccines to manipulate and modulate the immune system and applies innovative technologies toward improved understanding of the immune system in health and disease. Microfluidics has proven to be an excellent technology for analytics in biology and chemistry. From simple microsystem chips to complex microfluidic designs, these platforms have witnessed an immense growth over the last decades with frequent emergence of new designs. Microfluidics provides a highly robust and precise tool which led to its widespread application in single-cell analysis of immune cells. Single-cell analysis allows scientists to account for the heterogeneous behavior of immune cells which often gets overshadowed when conventional bulk study methods are used. Application of single-cell analysis using microfluidics has facilitated the identification of several novel functional immune cell subsets, quantification of signaling molecules, and understanding of cellular communication and signaling pathways. Single-cell analysis research in combination with microfluidics has paved the way for the development of novel therapies, point-of-care diagnostics, and even more complex microfluidic platforms that aid in creating in vitro cellular microenvironments for applications in drug and toxicity screening. In this review, we provide a comprehensive overview on the integration of microsystems and microfluidics with immunology and focus on different designs developed to decode single immune cell behavior and cellular communication. We have categorized the microfluidic designs in three specific categories: microfluidic chips with cell traps, valve-based microfluidics, and droplet microfluidics that have facilitated the ongoing research in the field of immunology at single-cell level.
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Affiliation(s)
- Nidhi Sinha
- Laboratory of Immunoengineering, Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven, Netherlands
- Institute for Complex Molecular Systems, Eindhoven University of Technology, Eindhoven, Netherlands
| | - Nikita Subedi
- Laboratory of Immunoengineering, Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven, Netherlands
- Institute for Complex Molecular Systems, Eindhoven University of Technology, Eindhoven, Netherlands
| | - Jurjen Tel
- Laboratory of Immunoengineering, Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven, Netherlands
- Institute for Complex Molecular Systems, Eindhoven University of Technology, Eindhoven, Netherlands
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Microfluidic Transfection for High-Throughput Mammalian Protein Expression. Methods Mol Biol 2018. [PMID: 30242688 DOI: 10.1007/978-1-4939-8730-6_13] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
Abstract
Mammalian synthetic biology and cell biology would greatly benefit from improved methods for highly parallel transfection, culturing, and interrogation of mammalian cells. Transfection is routinely performed on high-throughput microarrays, but this setup requires manual cell culturing and precludes precise control over the cell environment. As an alternative, microfluidic transfection devices streamline cell loading and culturing. Up to 280 transfections can be implemented on the chip at high efficiency. The culturing environment is tightly regulated and chambers physically separate the transfection reactions, preventing cross-contamination. Unlike typical biological assays that rely on end-point measurements, the microfluidic chip can be integrated with high-content imaging, enabling the evaluation of cellular behavior and protein expression dynamics over time.
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20
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Wang Q, Xu Y, Zuo S, Yao H, Ho TY, Li B, Schlichtmann U, Cai Y. Pressure-Aware Control Layer Optimization for Flow-Based Microfluidic Biochips. IEEE TRANSACTIONS ON BIOMEDICAL CIRCUITS AND SYSTEMS 2017; 11:1488-1499. [PMID: 29293429 DOI: 10.1109/tbcas.2017.2766210] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Flow-based microfluidic biochips are attracting increasing attention with successful biomedical applications. One critical issue with flow-based microfluidic biochips is the large number of microvalves that require peripheral control pins. Even using the broadcasting addressing scheme, i.e., one control pin controls multiple microvalves simultaneously, thousands of microvalves would still require hundreds of control prins, which is unrealistic. To address this critical challenge in control scalability, the control-layer multiplexer is introduced to effectively reduce the number of control pins into log scale of the number of microvalves. There are two practical design issues with the control-layer multiplexer: (1) the reliability issue caused by the frequent control-valve switching, and (2) the pressure degradation problem caused by the control-valve switching without pressure refreshing from the pressure source. This paper addresses these two design issues by the proposed Hamming-distance-based switching sequence optimization method and the XOR-based pressure refreshing method. Simulation results demonstrate the effectiveness and efficiency of the proposed methods with an average 77.2% (maximum 89.6%) improvement in total pressure refreshing cost, and an average 88.5% (maximum 90.0%) improvement in pressure deviation.
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21
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Szydzik C, Gavela AF, Herranz S, Roccisano J, Knoerzer M, Thurgood P, Khoshmanesh K, Mitchell A, Lechuga LM. An automated optofluidic biosensor platform combining interferometric sensors and injection moulded microfluidics. LAB ON A CHIP 2017; 17:2793-2804. [PMID: 28682395 DOI: 10.1039/c7lc00524e] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
A primary limitation preventing practical implementation of photonic biosensors within point-of-care platforms is their integration with fluidic automation subsystems. For most diagnostic applications, photonic biosensors require complex fluid handling protocols; this is especially prominent in the case of competitive immunoassays, commonly used for detection of low-concentration, low-molecular weight biomarkers. For this reason, complex automated microfluidic systems are needed to realise the full point-of-care potential of photonic biosensors. To fulfil this requirement, we propose an on-chip valve-based microfluidic automation module, capable of automating such complex fluid handling. This module is realised through application of a PDMS injection moulding fabrication technique, recently described in our previous work, which enables practical fabrication of normally closed pneumatically actuated elastomeric valves. In this work, these valves are configured to achieve multiplexed reagent addressing for an on-chip diaphragm pump, providing the sample and reagent processing capabilities required for automation of cyclic competitive immunoassays. Application of this technique simplifies fabrication and introduces the potential for mass production, bringing point-of-care integration of complex automated microfluidics into the realm of practicality. This module is integrated with a highly sensitive, label-free bimodal waveguide photonic biosensor, and is demonstrated in the context of a proof-of-concept biosensing assay, detecting the low-molecular weight antibiotic tetracycline.
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Affiliation(s)
- C Szydzik
- School of Engineering, RMIT University, Melbourne, Australia
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22
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Silva R, Bhatia S, Densmore D. A reconfigurable continuous-flow fluidic routing fabric using a modular, scalable primitive. LAB ON A CHIP 2016; 16:2730-2741. [PMID: 27345339 DOI: 10.1039/c6lc00477f] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Microfluidic devices, by definition, are required to move liquids from one physical location to another. Given a finite and frequently fixed set of physical channels to route fluids, a primitive design element that allows reconfigurable routing of that fluid from any of n input ports to any n output ports will dramatically change the paradigms by which these chips are designed and applied. Furthermore, if these elements are "regular" regarding their design, the programming and fabrication of these elements becomes scalable. This paper presents such a design element called a transposer. We illustrate the design, fabrication and operation of a single transposer. We then scale this design to create a programmable fabric towards a general-purpose, reconfigurable microfluidic platform analogous to the Field Programmable Gate Array (FPGA) found in digital electronics.
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Affiliation(s)
- Ryan Silva
- Boston University Department of Electrical and Computer Engineering, 8 Saint Mary's St., Boston, USA. and Biological Design Center, 610 Commonwealth Avenue, Boston, USA
| | - Swapnil Bhatia
- Boston University Department of Electrical and Computer Engineering, 8 Saint Mary's St., Boston, USA. and Biological Design Center, 610 Commonwealth Avenue, Boston, USA
| | - Douglas Densmore
- Boston University Department of Electrical and Computer Engineering, 8 Saint Mary's St., Boston, USA. and Biological Design Center, 610 Commonwealth Avenue, Boston, USA
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23
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Selections from the current literature. J Am Dent Assoc 2016. [DOI: 10.1016/j.adaj.2016.05.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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24
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Lam RHW, Cui X, Guo W, Thorsen T. High-throughput dental biofilm growth analysis for multiparametric microenvironmental biochemical conditions using microfluidics. LAB ON A CHIP 2016; 16:1652-62. [PMID: 27045372 DOI: 10.1039/c6lc00072j] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Dental biofilm formation is not only a precursor to tooth decay, but also induces more serious systematic health problems such as cardiovascular disease and diabetes. Understanding the conditions promoting colonization and subsequent biofilm development involving complex bacteria coaggregation is particularly important. In this paper, we report a high-throughput microfluidic 'artificial teeth' device offering controls of multiple microenvironmental factors (e.g. nutrients, growth factors, dissolved gases, and seeded cell populations) for quantitative characteristics of long-term dental bacteria growth and biofilm development. This 'artificial teeth' device contains multiple (up to 128) incubation chambers to perform parallel cultivation and analyses (e.g. biofilm thickness, viable-dead cell ratio, and spatial distribution of multiple bacterial species) of bacteria samples under a matrix of different combinations of microenvironmental factors, further revealing possible developmental mechanisms of dental biofilms. Specifically, we applied the 'artificial teeth' to investigate the growth of two key dental bacteria, Streptococci species and Fusobacterium nucleatum, in the biofilm under different dissolved gas conditions and sucrose concentrations. Together, this high-throughput microfluidic platform can provide extended applications for general biofilm research, including screening of the biofilm properties developing under combinations of specified growth parameters such as seeding bacteria populations, growth medium compositions, medium flow rates and dissolved gas levels.
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Affiliation(s)
- Raymond H W Lam
- Department of Mechanical and Biomedical Engineering, City University of Hong Kong, Hong Kong. and Centre for Robotics and Automation, City University of Hong Kong, Hong Kong and Centre for Biosystems, Neuroscience and Nanotechnology, City University of Hong Kong, Hong Kong
| | - Xin Cui
- Department of Mechanical and Biomedical Engineering, City University of Hong Kong, Hong Kong.
| | - Weijin Guo
- Department of Mechanical and Biomedical Engineering, City University of Hong Kong, Hong Kong.
| | - Todd Thorsen
- Department of Mechanical Engineering, Massachusetts Institute of Technology, Boston, USA.
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A High-Throughput Microfluidic Platform for Mammalian Cell Transfection and Culturing. Sci Rep 2016; 6:23937. [PMID: 27030663 PMCID: PMC4814922 DOI: 10.1038/srep23937] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2015] [Accepted: 03/16/2016] [Indexed: 11/28/2022] Open
Abstract
Mammalian synthetic biology could be augmented through the development of high-throughput microfluidic systems that integrate cellular transfection, culturing, and imaging. We created a microfluidic chip that cultures cells and implements 280 independent transfections at up to 99% efficiency. The chip can perform co-transfections, in which the number of cells expressing each protein and the average protein expression level can be precisely tuned as a function of input DNA concentration and synthetic gene circuits can be optimized on chip. We co-transfected four plasmids to test a histidine kinase signaling pathway and mapped the dose dependence of this network on the level of one of its constituents. The chip is readily integrated with high-content imaging, enabling the evaluation of cellular behavior and protein expression dynamics over time. These features make the transfection chip applicable to high-throughput mammalian protein and synthetic biology studies.
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26
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Gao Y, Tian J, Wu J, Cao W, Zhou B, Shen R, Wen W. Digital microfluidic programmable stencil (dMPS) for protein and cell patterning. RSC Adv 2016. [DOI: 10.1039/c6ra17633j] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Patterning biomolecules and cells on substrates is usually a prerequisite for biological analysis and cell studies.
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Affiliation(s)
- Yibo Gao
- Environmental Science Programs
- Hong Kong University of Science and Technology
- Kowloon
- Hong Kong
- Department of Physics
| | - Jingxuan Tian
- Department of Physics
- Hong Kong University of Science and Technology
- Kowloon
- Hong Kong
| | - Jinbo Wu
- Materials Genome Institute
- Shanghai University
- Shanghai 200444
- PR China
| | - Wenbin Cao
- Department of Physics
- Hong Kong University of Science and Technology
- Kowloon
- Hong Kong
| | - Bingpu Zhou
- Institute of Applied Physics and Materials Engineering
- Faculty of Science and Technology
- University of Macau
- Taipa
- PR China
| | - Rong Shen
- Institute of Physics
- Chinese Academy of Sciences
- Beijing
- PR China
| | - Weijia Wen
- Environmental Science Programs
- Hong Kong University of Science and Technology
- Kowloon
- Hong Kong
- Department of Physics
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27
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Volpetti F, Garcia-Cordero J, Maerkl SJ. A microfluidic platform for high-throughput multiplexed protein quantitation. PLoS One 2015; 10:e0117744. [PMID: 25680117 PMCID: PMC4334502 DOI: 10.1371/journal.pone.0117744] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2014] [Accepted: 12/31/2014] [Indexed: 11/18/2022] Open
Abstract
We present a high-throughput microfluidic platform capable of quantitating up to 384 biomarkers in 4 distinct samples by immunoassay. The microfluidic device contains 384 unit cells, which can be individually programmed with pairs of capture and detection antibody. Samples are quantitated in each unit cell by four independent MITOMI detection areas, allowing four samples to be analyzed in parallel for a total of 1,536 assays per device. We show that the device can be pre-assembled and stored for weeks at elevated temperature and we performed proof-of-concept experiments simultaneously quantitating IL-6, IL-1β, TNF-α, PSA, and GFP. Finally, we show that the platform can be used to identify functional antibody combinations by screening 64 antibody combinations requiring up to 384 unique assays per device.
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Affiliation(s)
- Francesca Volpetti
- Institute of Bioengineering, School of Engineering, Ecole Polytechnique Federale de Lausanne, Lausanne, Switzerland
| | - Jose Garcia-Cordero
- Institute of Bioengineering, School of Engineering, Ecole Polytechnique Federale de Lausanne, Lausanne, Switzerland
| | - Sebastian J. Maerkl
- Institute of Bioengineering, School of Engineering, Ecole Polytechnique Federale de Lausanne, Lausanne, Switzerland
- * E-mail:
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28
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29
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Huang H, Densmore D. Integration of microfluidics into the synthetic biology design flow. LAB ON A CHIP 2014; 14:3459-74. [PMID: 25012162 DOI: 10.1039/c4lc00509k] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
One goal of synthetic biology is to design and build genetic circuits in living cells for a range of applications. Major challenges in these efforts include increasing the scalability and robustness of engineered biological systems and streamlining and automating the synthetic biology workflow of specification-design-assembly-verification. We present here a summary of the advances in microfluidic technology, particularly microfluidic large scale integration, that can be used to address the challenges facing each step of the synthetic biology workflow. Microfluidic technologies allow precise control over the flow of biological content within microscale devices, and thus may provide more reliable and scalable construction of synthetic biological systems. The integration of microfluidics and synthetic biology has the capability to produce rapid prototyping platforms for characterization of genetic devices, testing of biotherapeutics, and development of biosensors.
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Affiliation(s)
- Haiyao Huang
- Department of Electrical and Computer Engineering, Boston University, Boston, MA 02215, USA.
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30
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Automated long-term monitoring of parallel microfluidic operations applying a machine vision-assisted positioning method. ScientificWorldJournal 2014; 2014:608184. [PMID: 25133248 PMCID: PMC4124227 DOI: 10.1155/2014/608184] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2014] [Accepted: 06/25/2014] [Indexed: 01/13/2023] Open
Abstract
As microfluidics has been applied extensively in many cell and biochemical applications, monitoring the related processes is an important requirement. In this work, we design and fabricate a high-throughput microfluidic device which contains 32 microchambers to perform automated parallel microfluidic operations and monitoring on an automated stage of a microscope. Images are captured at multiple spots on the device during the operations for monitoring samples in microchambers in parallel; yet the device positions may vary at different time points throughout operations as the device moves back and forth on a motorized microscopic stage. Here, we report an image-based positioning strategy to realign the chamber position before every recording of microscopic image. We fabricate alignment marks at defined locations next to the chambers in the microfluidic device as reference positions. We also develop image processing algorithms to recognize the chamber positions in real-time, followed by realigning the chambers to their preset positions in the captured images. We perform experiments to validate and characterize the device functionality and the automated realignment operation. Together, this microfluidic realignment strategy can be a platform technology to achieve precise positioning of multiple chambers for general microfluidic applications requiring long-term parallel monitoring of cell and biochemical activities.
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31
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Amin AM, Thakur R, Madren S, Chuang HS, Thottethodi M, Vijaykumar TN, Wereley ST, Jacobson SC. Software-programmable continuous-flow multi-purpose lab-on-a-chip. MICROFLUIDICS AND NANOFLUIDICS 2013; 15:647-659. [PMID: 24436691 PMCID: PMC3889662 DOI: 10.1007/s10404-013-1180-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
Current lab-on-a-chip (LoC) devices are assay-specific and are custom-built for each single experiment. Performing an experiment requires scientists or engineers to go through the time-consuming process of designing, fabricating, and testing a chip before conducting the actual experiment. This prolonged cycle can take months to complete, increasing effort and cost and reducing productivity. Similarly, minor modifications to an assay protocol re-incur the overheads of the design cycle. In this paper, we develop a multi-purpose, software-programmableLab-on-a-Chip (SPLoC), where the user simply writes or downloads a program for each experiment. We describe the components necessary to realize the SPLoC, which include a high-level programming language, an abstract instruction set, a runtime and control system, and a microfluidic device. We describe two key features of our high-level language compiler, and describe a novel variable-volume variable-ratio mixer. Finally, we demonstrate our SPLoC on four diverse, real-world assays.
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Affiliation(s)
- Ahmed M Amin
- Microfluidic Innovations, West Lafayette, IN 47906, USA
| | - Raviraj Thakur
- Birck Nanotechnology Center, School of Mechanical Engineering, Purdue University, West Lafayette, IN 47907, USA
| | - Seth Madren
- Department of Chemistry, Indiana University, Bloomington, IN 47405, USA
| | - Han-Sheng Chuang
- Department of Biomedical Engineering, National Cheng Kung University, Tainan, Taiwan
| | - Mithuna Thottethodi
- School of Electrical and Computer N.Engineering, Purdue University, West Lafayette, IN 47907, USA
| | - T N Vijaykumar
- School of Electrical and Computer N.Engineering, Purdue University, West Lafayette, IN 47907, USA
| | - Steven T Wereley
- Birck Nanotechnology Center, School of Mechanical Engineering, Purdue University, West Lafayette, IN 47907, USA
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32
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Araci IE, Brisk P. Recent developments in microfluidic large scale integration. Curr Opin Biotechnol 2013; 25:60-8. [PMID: 24484882 DOI: 10.1016/j.copbio.2013.08.014] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2013] [Revised: 08/21/2013] [Accepted: 08/22/2013] [Indexed: 11/30/2022]
Abstract
In 2002, Thorsen et al. integrated thousands of micromechanical valves on a single microfluidic chip and demonstrated that the control of the fluidic networks can be simplified through multiplexors [1]. This enabled realization of highly parallel and automated fluidic processes with substantial sample economy advantage. Moreover, the fabrication of these devices by multilayer soft lithography was easy and reliable hence contributed to the power of the technology; microfluidic large scale integration (mLSI). Since then, mLSI has found use in wide variety of applications in biology and chemistry. In the meantime, efforts to improve the technology have been ongoing. These efforts mostly focus on; novel materials, components, micromechanical valve actuation methods, and chip architectures for mLSI. In this review, these technological advances are discussed and, recent examples of the mLSI applications are summarized.
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Affiliation(s)
- Ismail Emre Araci
- Department of Bioengineering, Stanford University, Stanford and Howard Hughes Medical Institute, CA 94305, USA.
| | - Philip Brisk
- Department of Computer Science and Engineering, Bourns College of Engineering, University of California, Riverside, CA 92521, USA
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33
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Yu F, Horowitz MA, Quake SR. Microfluidic serial digital to analog pressure converter for arbitrary pressure generation and contamination-free flow control. LAB ON A CHIP 2013; 13:1911-8. [PMID: 23529280 DOI: 10.1039/c3lc41394b] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
Multilayer microfluidics based on PDMS (polydimethylsiloxane) soft lithography have offered parallelism and integration for biological and chemical sciences, where reduction in reaction volume and consistency of controlled variables across experiments translate into reduced cost, increased quantity and quality of data. One issue with push up or push down microfluidic control concept is the inability to provide multiple control pressures without adding more complex and expensive external pressure controls. We present here a microfluidic serial DAC (Digital to Analog Converter) that can be integrated with any PDMS device to expand the device's functionality by effectively adding an on-chip pressure regulator. The microfluidic serial DAC can be used with any incompressible fluids and operates in a similar fashion compared to an electronic serial DAC. It can be easily incorporated into any existing multilayer microfluidic devices, and the output pressure that the device generates could be held for extensive times. We explore in this paper various factors that affect resolution, speed, and linearity of the DAC output. As an application, we demonstrate microfluidic DAC's ability for on-chip manipulation of flow resistance when integrated with a simple flow network. In addition, we illustrate an added advantage of using the microfluidic serial DAC in preventing back flow and possible contamination.
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Affiliation(s)
- Feiqiao Yu
- Departments of Bioengineering and Applied Physics, Stanford University and Howard Hughes Medical Institute, Stanford, California 94305, USA
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34
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Naito T, Arayanarakool R, Le Gac S, Yasui T, Kaji N, Tokeshi M, van den Berg A, Baba Y. Temperature-driven self-actuated microchamber sealing system for highly integrated microfluidic devices. LAB ON A CHIP 2013; 13:452-458. [PMID: 23235490 DOI: 10.1039/c2lc41030c] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
We present here a novel microchamber sealing valve that is self-actuated by a pressure change during the temperature change in the thermal activation of reactions. Actuation of our valve requires only the use of the same heating device as employed for the reactions. A thermoplastic UV-curable polymer is used as a device material; the polymer allows realization of the temperature-driven valve actuation as well as the fabrication of multi-layered devices. The self-actuated valve achieves effective sealing of the microchamber for the polymerase chain reaction (PCR) even at 90 °C, which is essential for developing highly parallel PCR array devices without the need for complicated peripherals to control the valve operation.
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Affiliation(s)
- Toyohiro Naito
- Department of Applied Chemistry, Graduate School of Engineering, Nagoya University, FIRST Chikusa-ku, Nagoya, Japan.
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35
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Kovarik ML, Ornoff DM, Melvin AT, Dobes NC, Wang Y, Dickinson AJ, Gach PC, Shah PK, Allbritton NL. Micro total analysis systems: fundamental advances and applications in the laboratory, clinic, and field. Anal Chem 2013; 85:451-72. [PMID: 23140554 PMCID: PMC3546124 DOI: 10.1021/ac3031543] [Citation(s) in RCA: 170] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
- Michelle L. Kovarik
- Department of Chemistry, University of North Carolina, Chapel Hill, North Carolina 27599
| | - Douglas M. Ornoff
- Department of Pharmacology, University of North Carolina, Chapel Hill, North Carolina 27599
| | - Adam T. Melvin
- Department of Chemistry, University of North Carolina, Chapel Hill, North Carolina 27599
| | - Nicholas C. Dobes
- Department of Chemistry, University of North Carolina, Chapel Hill, North Carolina 27599
| | - Yuli Wang
- Department of Chemistry, University of North Carolina, Chapel Hill, North Carolina 27599
| | - Alexandra J. Dickinson
- Department of Chemistry, University of North Carolina, Chapel Hill, North Carolina 27599
| | - Philip C. Gach
- Department of Chemistry, University of North Carolina, Chapel Hill, North Carolina 27599
| | - Pavak K. Shah
- Department of Biomedical Engineering, University of North Carolina, Chapel Hill, NC 27599 and North Carolina State University, Raleigh, NC 27695
| | - Nancy L. Allbritton
- Department of Chemistry, University of North Carolina, Chapel Hill, North Carolina 27599
- Department of Pharmacology, University of North Carolina, Chapel Hill, North Carolina 27599
- Department of Biomedical Engineering, University of North Carolina, Chapel Hill, NC 27599 and North Carolina State University, Raleigh, NC 27695
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36
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Tehranirokh M, Kouzani AZ, Francis PS, Kanwar JR. Microfluidic devices for cell cultivation and proliferation. BIOMICROFLUIDICS 2013; 7:51502. [PMID: 24273628 PMCID: PMC3829894 DOI: 10.1063/1.4826935] [Citation(s) in RCA: 84] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/11/2013] [Accepted: 09/24/2013] [Indexed: 05/07/2023]
Abstract
Microfluidic technology provides precise, controlled-environment, cost-effective, compact, integrated, and high-throughput microsystems that are promising substitutes for conventional biological laboratory methods. In recent years, microfluidic cell culture devices have been used for applications such as tissue engineering, diagnostics, drug screening, immunology, cancer studies, stem cell proliferation and differentiation, and neurite guidance. Microfluidic technology allows dynamic cell culture in microperfusion systems to deliver continuous nutrient supplies for long term cell culture. It offers many opportunities to mimic the cell-cell and cell-extracellular matrix interactions of tissues by creating gradient concentrations of biochemical signals such as growth factors, chemokines, and hormones. Other applications of cell cultivation in microfluidic systems include high resolution cell patterning on a modified substrate with adhesive patterns and the reconstruction of complicated tissue architectures. In this review, recent advances in microfluidic platforms for cell culturing and proliferation, for both simple monolayer (2D) cell seeding processes and 3D configurations as accurate models of in vivo conditions, are examined.
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37
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Manina G, McKinney JD. A single-cell perspective on non-growing but metabolically active (NGMA) bacteria. Curr Top Microbiol Immunol 2013; 374:135-61. [PMID: 23793585 DOI: 10.1007/82_2013_333] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
A long-standing and fundamental problem in microbiology is the non-trivial discrimination between live and dead cells. The existence of physically intact and possibly viable bacterial cells that fail to replicate during a more or less protracted period of observation, despite environmental conditions that are ostensibly propitious for growth, has been extensively documented in many different organisms. In clinical settings, non-culturable cells may contribute to non-apparent infections capable of reactivating after months or years of clinical latency, a phenomenon that has been well documented in the specific case of Mycobacterium tuberculosis. The prevalence of these silent but potentially problematic bacterial reservoirs has been highlighted by classical approaches such as limiting culture dilution till extinction of growing cells, followed by resuscitation of apparently "viable but non-culturable" (VBNC) subpopulations. Although these assays are useful to demonstrate the presence of VBNC cells in a population, they are effectively retrospective and are not well suited to the analysis of non-replicating cells per se. Here, we argue that research on a closely related problem, which we shall refer to as the "non-growing but metabolically active" state, is poised to advance rapidly thanks to the recent development of novel technologies and methods for real-time single-cell analysis. In particular, the combination of fluorescent reporter dyes and strains, microfluidic and microelectromechanical systems, and time-lapse fluorescence microscopy offers tremendous and largely untapped potential for future exploration of the physiology of non-replicating cells.
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Affiliation(s)
- Giulia Manina
- School of Life Sciences, Swiss Federal Institute of Technology in Lausanne (EPFL), 1015, Lausanne, Switzerland,
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Madren SM, Hoffman MD, Brown PJ, Kysela DT, Brun YV, Jacobson SC. Microfluidic device for automated synchronization of bacterial cells. Anal Chem 2012; 84:8571-8. [PMID: 23030473 PMCID: PMC3484264 DOI: 10.1021/ac301565g] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
We report the development of an automated microfluidic "baby machine" to synchronize the bacterium Caulobacter crescentus on-chip and to move the synchronized populations downstream for analysis. The microfluidic device is fabricated from three layers of poly(dimethylsiloxane) and has integrated pumps and valves to control the movement of cells and media. This synchronization method decreases incubation time and media consumption and improves synchrony quality compared to the conventional plate-release technique. Synchronized populations are collected from the device at intervals as short as 10 min and at any time over four days. Flow cytometry and fluorescence cell tracking are used to determine synchrony quality, and cell populations synchronized in minimal growth medium with 0.2% glucose (M2G) and peptone yeast extract (PYE) medium contain >70% and >80% swarmer cells, respectively. Our on-chip method overcomes limitations with conventional physical separation methods that consume large volumes of media, require manual manipulations, have lengthy incubation times, are limited to one collection, and lack precise temporal control of collection times.
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Affiliation(s)
- Seth M. Madren
- Department of Chemistry, Indiana University, Bloomington, IN 47405-7102
| | | | - Pamela J.B. Brown
- Department of Biology, Indiana University, Bloomington, IN 47405-3700
| | - David T. Kysela
- Department of Biology, Indiana University, Bloomington, IN 47405-3700
| | - Yves V. Brun
- Department of Biology, Indiana University, Bloomington, IN 47405-3700
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Kim SJ, Lai D, Park JY, Yokokawa R, Takayama S. Microfluidic automation using elastomeric valves and droplets: reducing reliance on external controllers. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2012; 8:2925-34. [PMID: 22761019 PMCID: PMC3463711 DOI: 10.1002/smll.201200456] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/29/2012] [Revised: 05/02/2012] [Indexed: 05/04/2023]
Abstract
This paper gives an overview of elastomeric valve- and droplet-based microfluidic systems designed to minimize the need of external pressure to control fluid flow. This Concept article introduces the working principle of representative components in these devices along with relevant biochemical applications. This is followed by providing a perspective on the roles of different microfluidic valves and systems through comparison of their similarities and differences with transistors (valves) and systems in microelectronics. Despite some physical limitation of drawing analogies from electronic circuits, automated microfluidic circuit design can gain insights from electronic circuits to minimize external control units, while implementing high-complexity and high-throughput analysis.
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Affiliation(s)
- Sung-Jin Kim
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI, 48109, USA
| | - David Lai
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI, 48109, USA
| | - Joong Yull Park
- School of Mechanical Engineering, Chung-Ang University, Seoul, Republic of Korea
| | - Ryuji Yokokawa
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI, 48109, USA
- Department of Microengineering, Kyoto University, Yoshida-honmachi, Sakyo, Kyoto, 606-8501 JAPAN
| | - Shuichi Takayama
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI, 48109, USA
- Department of Macromolecular Science and Engineering, University of Michigan, Ann Arbor, MI, 48109, USA; Division of Nano-Bio and Chemical Engineering WCU Project, UNIST, Ulsan, Republic of Korea
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A programmable droplet-based microfluidic device applied to multiparameter analysis of single microbes and microbial communities. Proc Natl Acad Sci U S A 2012; 109:7665-70. [PMID: 22547789 DOI: 10.1073/pnas.1106752109] [Citation(s) in RCA: 165] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
We present a programmable droplet-based microfluidic device that combines the reconfigurable flow-routing capabilities of integrated microvalve technology with the sample compartmentalization and dispersion-free transport that is inherent to droplets. The device allows for the execution of user-defined multistep reaction protocols in 95 individually addressable nanoliter-volume storage chambers by consecutively merging programmable sequences of picoliter-volume droplets containing reagents or cells. This functionality is enabled by "flow-controlled wetting," a droplet docking and merging mechanism that exploits the physics of droplet flow through a channel to control the precise location of droplet wetting. The device also allows for automated cross-contamination-free recovery of reaction products from individual chambers into standard microfuge tubes for downstream analysis. The combined features of programmability, addressability, and selective recovery provide a general hardware platform that can be reprogrammed for multiple applications. We demonstrate this versatility by implementing multiple single-cell experiment types with this device: bacterial cell sorting and cultivation, taxonomic gene identification, and high-throughput single-cell whole genome amplification and sequencing using common laboratory strains. Finally, we apply the device to genome analysis of single cells and microbial consortia from diverse environmental samples including a marine enrichment culture, deep-sea sediments, and the human oral cavity. The resulting datasets capture genotypic properties of individual cells and illuminate known and potentially unique partnerships between microbial community members.
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Lecault V, White AK, Singhal A, Hansen CL. Microfluidic single cell analysis: from promise to practice. Curr Opin Chem Biol 2012; 16:381-90. [PMID: 22525493 DOI: 10.1016/j.cbpa.2012.03.022] [Citation(s) in RCA: 159] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2012] [Accepted: 03/23/2012] [Indexed: 11/28/2022]
Abstract
Methods for single-cell analysis are critical to revealing cell-to-cell variability in biological systems, especially in cases where relevant minority cell populations can be obscured by population-averaged measurements. However, to date single cell studies have been limited by the cost and throughput required to examine large numbers of cells and the difficulties associated with analyzing small amounts of starting material. Microfluidic approaches are well suited to resolving these issues by providing increased senstitivity, economy of scale, and automation. After many years of development microfluidic systems are now finding traction in a variety of single-cell analytics including gene expression measurements, protein analysis, signaling response, and growth dynamics. With newly developed tools now being applied in fields ranging from human haplotyping and drug discovery to stem cell and cancer research, the long-heralded promise of microfluidic single cell analysis is now finally being realized.
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Affiliation(s)
- Véronique Lecault
- Centre for High-Throughput Biology, University of British Columbia, 2185 East Mall, Vancouver, British Columbia, V6T 1Z4, Canada
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Ranga A, Lutolf MP. High-throughput approaches for the analysis of extrinsic regulators of stem cell fate. Curr Opin Cell Biol 2012; 24:236-44. [DOI: 10.1016/j.ceb.2012.01.006] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2012] [Accepted: 01/12/2012] [Indexed: 01/10/2023]
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Banerjee A, Kreit E, Liu Y, Heikenfeld J, Papautsky I. Reconfigurable virtual electrowetting channels. LAB ON A CHIP 2012; 12:758-764. [PMID: 22159496 DOI: 10.1039/c2lc20842c] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Lab-on-a-chip systems rely on several microfluidic paradigms. The first uses a fixed layout of continuous microfluidic channels. Such lab-on-a-chip systems are almost always application specific and far from a true "laboratory." The second involves electrowetting droplet movement (digital microfluidics), and allows two-dimensional computer control of fluidic transport and mixing. The merging of the two paradigms in the form of programmable electrowetting channels takes advantage of both the "continuous" functionality of rigid channels based on which a large number of applications have been developed to date and the "programmable" functionality of digital microfluidics that permits electrical control of on-chip functions. In this work, we demonstrate for the first time programmable formation of virtual microfluidic channels and their continuous operation with pressure driven flows using an electrowetting platform. Experimental, theoretical, and numerical analyses of virtual channel formation with biologically relevant electrolyte solutions and electrically-programmable reconfiguration are presented. We demonstrate that the "wall-less" virtual channels can be formed reliably and rapidly, with propagation rates of 3.5-3.8 mm s(-1). Pressure driven transport in these virtual channels at flow rates up to 100 μL min(-1) is achievable without distortion of the channel shape. We further demonstrate that these virtual channels can be switched on-demand between multiple inputs and outputs. Ultimately, we envision a platform that would provide rapid prototyping of microfluidic concepts and would be capable of a vast library of functions and benefitting applications from clinical diagnostics in resource-limited environments to rapid system prototyping to high throughput pharmaceutical applications.
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Affiliation(s)
- Ananda Banerjee
- BioMicroSystems Laboratory, School of Electronic and Computing Systems, University of Cincinnati, Cincinnati, OH 45221, USA
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Kovarik ML, Gach PC, Ornoff DM, Wang Y, Balowski J, Farrag L, Allbritton NL. Micro total analysis systems for cell biology and biochemical assays. Anal Chem 2012; 84:516-40. [PMID: 21967743 PMCID: PMC3264799 DOI: 10.1021/ac202611x] [Citation(s) in RCA: 180] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Michelle L. Kovarik
- Department of Chemistry, University of North Carolina, Chapel Hill, North Carolina 27599
| | - Phillip C. Gach
- Department of Chemistry, University of North Carolina, Chapel Hill, North Carolina 27599
| | - Douglas M. Ornoff
- Department of Chemistry, University of North Carolina, Chapel Hill, North Carolina 27599
- Department of Pharmacology, University of North Carolina, Chapel Hill, North Carolina 27599
| | - Yuli Wang
- Department of Chemistry, University of North Carolina, Chapel Hill, North Carolina 27599
| | - Joseph Balowski
- Department of Chemistry, University of North Carolina, Chapel Hill, North Carolina 27599
| | - Lila Farrag
- School of Medicine, University of North Carolina, Chapel Hill, North Carolina 27599
| | - Nancy L. Allbritton
- Department of Chemistry, University of North Carolina, Chapel Hill, North Carolina 27599
- Department of Biomedical Engineering, University of North Carolina, Chapel Hill, NC 27599 and North Carolina State University, Raleigh, NC 27695
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Pollack MG, Pamula VK, Srinivasan V, Eckhardt AE. Applications of electrowetting-based digital microfluidics in clinical diagnostics. Expert Rev Mol Diagn 2011; 11:393-407. [PMID: 21545257 DOI: 10.1586/erm.11.22] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Digital microfluidics based on electrowetting is a type of microfluidic platform in which liquids are processed as individual unit-sized droplets that are dispensed from a source, merged together, split apart or transported between locations on demand. These devices are implemented using arrays of surface electrodes to control the shape and position of droplets through the electrowetting effect. A major thrust of digital microfluidics research has been the development of integrated lab-on-a-chip devices to perform clinical in vitro diagnostic assays. A variety of preparatory and analytical processes have been implemented and feasibility has been demonstrated for test types ranging from clinical chemistries to immunoassays, nucleic acid tests and cell-based assays. In this article, the current state and future potential of digital microfluidics for clinical diagnostic testing is reviewed and evaluated.
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Affiliation(s)
- Michael G Pollack
- Advanced Liquid Logic, Inc., PO Box 14025, Research Triangle Park, NC 27709, USA.
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