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Hou JF, Nayeem MOG, Caplan KA, Ruesch EA, Caban-Murillo A, Criado-Hidalgo E, Ornellas SB, Williams B, Pearce AA, Dagdeviren HE, Surets M, White JA, Shapiro MG, Wang F, Ramirez S, Dagdeviren C. An implantable piezoelectric ultrasound stimulator (ImPULS) for deep brain activation. Nat Commun 2024; 15:4601. [PMID: 38834558 PMCID: PMC11150473 DOI: 10.1038/s41467-024-48748-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2023] [Accepted: 05/13/2024] [Indexed: 06/06/2024] Open
Abstract
Precise neurostimulation can revolutionize therapies for neurological disorders. Electrode-based stimulation devices face challenges in achieving precise and consistent targeting due to the immune response and the limited penetration of electrical fields. Ultrasound can aid in energy propagation, but transcranial ultrasound stimulation in the deep brain has limited spatial resolution caused by bone and tissue scattering. Here, we report an implantable piezoelectric ultrasound stimulator (ImPULS) that generates an ultrasonic focal pressure of 100 kPa to modulate the activity of neurons. ImPULS is a fully-encapsulated, flexible piezoelectric micromachined ultrasound transducer that incorporates a biocompatible piezoceramic, potassium sodium niobate [(K,Na)NbO3]. The absence of electrochemically active elements poses a new strategy for achieving long-term stability. We demonstrated that ImPULS can i) excite neurons in a mouse hippocampal slice ex vivo, ii) activate cells in the hippocampus of an anesthetized mouse to induce expression of activity-dependent gene c-Fos, and iii) stimulate dopaminergic neurons in the substantia nigra pars compacta to elicit time-locked modulation of nigrostriatal dopamine release. This work introduces a non-genetic ultrasound platform for spatially-localized neural stimulation and exploration of basic functions in the deep brain.
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Affiliation(s)
- Jason F Hou
- Media Lab, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
| | | | - Kian A Caplan
- Department of Brain and Cognitive Sciences, McGovern Institute for Brain Research, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
| | - Evan A Ruesch
- Department of Psychological and Brain Sciences, The Center for Systems Neuroscience, Boston University, Boston, 02215, MA, USA
| | - Albit Caban-Murillo
- Department of Psychological and Brain Sciences, The Center for Systems Neuroscience, Boston University, Boston, 02215, MA, USA
| | - Ernesto Criado-Hidalgo
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA, 91125, USA
| | - Sarah B Ornellas
- Media Lab, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
| | - Brandon Williams
- Center for Systems Neuroscience, Neurophotonics Center, Department of Biomedical Engineering, Boston University, 610 Commonwealth Ave., Boston, MA, 02215, USA
| | - Ayeilla A Pearce
- Department of Brain and Cognitive Sciences, McGovern Institute for Brain Research, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
| | - Huseyin E Dagdeviren
- Department of Neurosurgery, Faculty of Medicine, Istanbul University, Istanbul, 34093, Turkey
| | - Michelle Surets
- Department of Psychological and Brain Sciences, The Center for Systems Neuroscience, Boston University, Boston, 02215, MA, USA
| | - John A White
- Center for Systems Neuroscience, Neurophotonics Center, Department of Biomedical Engineering, Boston University, 610 Commonwealth Ave., Boston, MA, 02215, USA
| | - Mikhail G Shapiro
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA, 91125, USA
| | - Fan Wang
- Department of Brain and Cognitive Sciences, McGovern Institute for Brain Research, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
| | - Steve Ramirez
- Department of Psychological and Brain Sciences, The Center for Systems Neuroscience, Boston University, Boston, 02215, MA, USA
| | - Canan Dagdeviren
- Media Lab, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA.
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2
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Yu L, Le Nagard L, Barkley S, Smith L, Fradin C. Experimental determination of the propulsion matrix of the body of helical Magnetospirillum magneticum cells. Phys Rev E 2022; 106:034407. [PMID: 36266829 DOI: 10.1103/physreve.106.034407] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2021] [Accepted: 06/07/2022] [Indexed: 06/16/2023]
Abstract
Helical-shaped magnetotactic bacteria provide a rare opportunity to precisely measure both the translational and rotational friction coefficients of micron-sized chiral particles. The possibility to align these cells with a uniform magnetic field allows clearly separating diffusion along and perpendicular to their longitudinal axis. Meanwhile, their corkscrew shape allows detecting rotations around their longitudinal axis, after which orientation correlation analysis can be used to retrieve rotational diffusion coefficients in the two principal directions. Using light microscopy, we measured the four principal friction coefficients of deflagellated Magnetospirillum magneticum cells, and compared our results to that expected for cylinders of comparable size. We show that for rotational motions, the overall dimensions of the cell body are what matters most, while the exact body shape has a larger influence on translational motions. To obtain a full characterization of the friction matrix of these elongated chiral particles, we also quantified the coupling between the rotation around and translation along the longitudinal axis of the cell. Our results suggest that for this bacterial species cell body rotation could significantly contribute to cellular propulsion.
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Affiliation(s)
- Liu Yu
- Department of Physics and Astronomy, McMaster University, 1280 Main Street W, Hamilton, Ontario L8S4M1, Canada
| | - Lucas Le Nagard
- Department of Physics and Astronomy, McMaster University, 1280 Main Street W, Hamilton, Ontario L8S4M1, Canada
| | - Solomon Barkley
- Department of Physics and Astronomy, McMaster University, 1280 Main Street W, Hamilton, Ontario L8S4M1, Canada
| | - Lauren Smith
- Department of Physics and Astronomy, McMaster University, 1280 Main Street W, Hamilton, Ontario L8S4M1, Canada
| | - Cécile Fradin
- Department of Physics and Astronomy, McMaster University, 1280 Main Street W, Hamilton, Ontario L8S4M1, Canada
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3
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Density fluctuations, homeostasis, and reproduction effects in bacteria. Commun Biol 2022; 5:397. [PMID: 35484403 PMCID: PMC9050864 DOI: 10.1038/s42003-022-03348-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2021] [Accepted: 04/10/2022] [Indexed: 12/02/2022] Open
Abstract
Single-cells grow by increasing their biomass and size. Here, we report that while mass and size accumulation rates of single Escherichia coli cells are exponential, their density and, thus, the levels of macromolecular crowding fluctuate during growth. As such, the average rates of mass and size accumulation of a single cell are generally not the same, but rather cells differentiate into increasing one rate with respect to the other. This differentiation yields a density homeostasis mechanism that we support mathematically. Further, we observe that density fluctuations can affect the reproduction rates of single cells, suggesting a link between the levels of macromolecular crowding with metabolism and overall population fitness. We detail our experimental approach and the “invisible” microfluidic arrays that enabled increased precision and throughput. Infections and natural communities start from a few cells, thus, emphasizing the significance of density-fluctuations when taking non-genetic variability into consideration. Quantitative imaging, invisible microfluidics, and mathematical models demonstrate how the density of single E. coli cells fluctuates during the cell cycle, unmasking key homeostasis and population fitness effects.
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4
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Matson MM, Cepeda MM, Zhang A, Case AE, Kavvas ES, Wang X, Carroll AL, Tagkopoulos I, Atsumi S. Adaptive laboratory evolution for improved tolerance of isobutyl acetate in Escherichia coli. Metab Eng 2021; 69:50-58. [PMID: 34763090 DOI: 10.1016/j.ymben.2021.11.002] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2021] [Revised: 10/14/2021] [Accepted: 11/04/2021] [Indexed: 02/08/2023]
Abstract
Previously, Escherichia coli was engineered to produce isobutyl acetate (IBA). Titers greater than the toxicity threshold (3 g/L) were achieved by using layer-assisted production. To avoid this costly and complex method, adaptive laboratory evolution (ALE) was applied to E. coli for improved IBA tolerance. Over 37 rounds of selective pressure, 22 IBA-tolerant mutants were isolated. Remarkably, these mutants not only tolerate high IBA concentrations, they also produce higher IBA titers. Using whole-genome sequencing followed by CRISPR/Cas9 mediated genome editing, the mutations (SNPs in metH, rho and deletion of arcA) that confer improved tolerance and higher titers were elucidated. The improved IBA titers in the evolved mutants were a result of an increased supply of acetyl-CoA and altered transcriptional machinery. Without the use of phase separation, a strain capable of 3.2-fold greater IBA production than the parent strain was constructed by combing select beneficial mutations. These results highlight the impact improved tolerance has on the production capability of a biosynthetic system.
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Affiliation(s)
- Morgan M Matson
- Department of Chemistry, University of California, Davis, CA, 95616, USA
| | - Mateo M Cepeda
- Department of Chemistry, University of California, Davis, CA, 95616, USA
| | - Angela Zhang
- Department of Chemistry, University of California, Davis, CA, 95616, USA
| | - Anna E Case
- Department of Chemistry, University of California, Davis, CA, 95616, USA
| | - Erol S Kavvas
- Genome Center, University of California, Davis, CA, 95616, USA
| | - Xiaokang Wang
- Genome Center, University of California, Davis, CA, 95616, USA; Department of Biomedical Engineering, University of California, Davis, CA 95616, USA
| | - Austin L Carroll
- Department of Chemistry, University of California, Davis, CA, 95616, USA
| | - Ilias Tagkopoulos
- Genome Center, University of California, Davis, CA, 95616, USA; Department of Computer Science, University of California, Davis, CA, 95616, USA
| | - Shota Atsumi
- Department of Chemistry, University of California, Davis, CA, 95616, USA.
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5
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Zhang F, Jiang C, Li Y, Niu X, Long T, He C, Ding J, Li L, Li L. Investigation of Artifacts and Optimization in Proton Resonance Frequency Thermometry Towards Heating Risk Monitoring of Implantable Medical Devices in Magnetic Resonance Imaging. IEEE Trans Biomed Eng 2021; 68:3638-3646. [PMID: 34003743 DOI: 10.1109/tbme.2021.3081599] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
OBJECTIVE Artifacts limit the application of proton resonance frequency (PRF) thermometry for on-site, individualized heating evaluations of implantable medical devices such as deep brain stimulation (DBS) for use in magnetic resonance imaging (MRI). Its properties are unclear and the research on how to choose an unaffected measurement region is insufficient. METHODS The properties of PRF signals around the metallic DBS electrode were investigated through simulations and phantom experiments considering electromagnetic interferences from material susceptibility and the radio frequency (RF) interactions. A threshold method on phase difference Δϕ was used to define a measurement area to estimate heating at the electrode surface. Its performance was compared to that of the Bayesian magnitude method and probe measurements. RESULTS The B0 magnetic field inhomogeneity due to the electrode susceptibility was the main influencing factor on PRF compared to the RF artifact. Δϕ around the electrode followed normal distribution but was distorted. Underestimation occurred at places with high temperature rises. The noise was increased and could be well estimated from magnitude images using a modified NEMA method. The Δϕ-threshold method based on this knowledge outperformed the Bayesian magnitude method by more than 42% in estimation error of the electrode heating. CONCLUSION The findings favor the use of PRF with the proposed approach as a reliable method for electrode heating estimation. SIGNIFICANCE This study clarified the influence of device artifacts and could improve the performance of PRF thermometry for individualized heating assessments of patients with implants under MRI.
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6
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Hassan SU, Tariq A, Noreen Z, Donia A, Zaidi SZJ, Bokhari H, Zhang X. Capillary-Driven Flow Microfluidics Combined with Smartphone Detection: An Emerging Tool for Point-of-Care Diagnostics. Diagnostics (Basel) 2020; 10:E509. [PMID: 32708045 PMCID: PMC7459612 DOI: 10.3390/diagnostics10080509] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2020] [Revised: 07/20/2020] [Accepted: 07/20/2020] [Indexed: 12/20/2022] Open
Abstract
Point-of-care (POC) or near-patient testing allows clinicians to accurately achieve real-time diagnostic results performed at or near to the patient site. The outlook of POC devices is to provide quicker analyses that can lead to well-informed clinical decisions and hence improve the health of patients at the point-of-need. Microfluidics plays an important role in the development of POC devices. However, requirements of handling expertise, pumping systems and complex fluidic controls make the technology unaffordable to the current healthcare systems in the world. In recent years, capillary-driven flow microfluidics has emerged as an attractive microfluidic-based technology to overcome these limitations by offering robust, cost-effective and simple-to-operate devices. The internal wall of the microchannels can be pre-coated with reagents, and by merely dipping the device into the patient sample, the sample can be loaded into the microchannel driven by capillary forces and can be detected via handheld or smartphone-based detectors. The capabilities of capillary-driven flow devices have not been fully exploited in developing POC diagnostics, especially for antimicrobial resistance studies in clinical settings. The purpose of this review is to open up this field of microfluidics to the ever-expanding microfluidic-based scientific community.
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Affiliation(s)
- Sammer-Ul Hassan
- Bioengineering Research Group, Faculty of Engineering and Physical Sciences, University of Southampton, Southampton SO17 1BJ, UK
- Institute for Life Sciences, University of Southampton, Southampton SO17 1BJ, UK
| | - Aamira Tariq
- Department of Biosciences, Comsats University Islamabad Campus, Islamabad, Pakistan
| | - Zobia Noreen
- Department of Biosciences, Comsats University Islamabad Campus, Islamabad, Pakistan
| | - Ahmed Donia
- Department of Biosciences, Comsats University Islamabad Campus, Islamabad, Pakistan
| | - Syed Z J Zaidi
- Institute of Chemical Engineering and Technology, University of the Punjab, Lahore, Pakistan
| | - Habib Bokhari
- Department of Biosciences, Comsats University Islamabad Campus, Islamabad, Pakistan
| | - Xunli Zhang
- Bioengineering Research Group, Faculty of Engineering and Physical Sciences, University of Southampton, Southampton SO17 1BJ, UK
- Institute for Life Sciences, University of Southampton, Southampton SO17 1BJ, UK
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7
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Roh YH, Moon JY, Hong EJ, Kim HU, Shim MS, Bong KW. Microfluidic fabrication of biocompatible poly(N-vinylcaprolactam)-based microcarriers for modulated thermo-responsive drug release. Colloids Surf B Biointerfaces 2018; 172:380-386. [PMID: 30193197 DOI: 10.1016/j.colsurfb.2018.08.059] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2018] [Revised: 08/16/2018] [Accepted: 08/27/2018] [Indexed: 11/27/2022]
Abstract
Various thermo-responsive polymers have been developed for controlled drug delivery upon the local application of external heat. The development of thermo-responsive polymers with high biocompatibility and tunable thermo-sensitivity is crucial for safe and efficient therapeutic application. In this study, thermo-responsive drug carriers featuring tunable thermo-sensitivities were synthesized using biocompatible poly(N-vinyl caprolactam) (PVCL) and stop-flow lithography. The PVCL-based particles showed selective drug release depending on temperature, illustrating their feasibility for on-demand controlled drug delivery. The volume phase transition temperature (VPTT) of the PVCL-based particles can be adjusted to vary from room temperature to body temperature by controlling their monomer compositions. In addition, modulated drug release was achieved by constructing multicompartments of different thermo-sensitivities within the PVCL particles. To accomplish thermo-responsive anticancer therapy, doxorubicin (DOX) was encapsulated into the PVCL particles as an anticancer drug. The DOX-loaded PVCL particles exhibited both thermo-responsive drug release and anticancer activity. This study demonstrates that thermo-responsive PVCL particles are highly promising carriers for safe and targeted anticancer therapy.
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Affiliation(s)
- Yoon Ho Roh
- Department of Chemical and Biological Engineering, Korea University, 145, Anam-ro, Seongbuk-gu, Seoul, 02841, Republic of Korea
| | - Ju Yeon Moon
- Department of Chemical and Biological Engineering, Korea University, 145, Anam-ro, Seongbuk-gu, Seoul, 02841, Republic of Korea
| | - Eun Ji Hong
- Division of Bioengineering, Incheon National University, 119, Academy-ro, Yeonsu-gu, Incheon, 22012, Republic of Korea
| | - Hyeon Ung Kim
- Department of Chemical and Biological Engineering, Korea University, 145, Anam-ro, Seongbuk-gu, Seoul, 02841, Republic of Korea
| | - Min Suk Shim
- Division of Bioengineering, Incheon National University, 119, Academy-ro, Yeonsu-gu, Incheon, 22012, Republic of Korea.
| | - Ki Wan Bong
- Department of Chemical and Biological Engineering, Korea University, 145, Anam-ro, Seongbuk-gu, Seoul, 02841, Republic of Korea.
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8
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Wu H, Chen X, Gao X, Zhang M, Wu J, Wen W. High-Throughput Generation of Durable Droplet Arrays for Single-Cell Encapsulation, Culture, and Monitoring. Anal Chem 2018; 90:4303-4309. [DOI: 10.1021/acs.analchem.8b00048] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Affiliation(s)
- Han Wu
- Materials Genome Institute, Shanghai University, Shanghai 200444, China
- College of Science, Shanghai University, Shanghai 200444, China
| | - Xinlian Chen
- Materials Genome Institute, Shanghai University, Shanghai 200444, China
| | - Xinghua Gao
- Materials Genome Institute, Shanghai University, Shanghai 200444, China
| | - Mengying Zhang
- Materials Genome Institute, Shanghai University, Shanghai 200444, China
- College of Science, Shanghai University, Shanghai 200444, China
| | - Jinbo Wu
- Materials Genome Institute, Shanghai University, Shanghai 200444, China
| | - Weijia Wen
- Materials Genome Institute, Shanghai University, Shanghai 200444, China
- Department of Physics, The Hong Kong University of Science and Technology, Hong Kong, China
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9
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Kim M, Bae J, Kim T. Long-Term and Programmable Bacterial Subculture in Completely Automated Microchemostats. Anal Chem 2017; 89:9676-9684. [DOI: 10.1021/acs.analchem.7b01076] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Affiliation(s)
- Minseok Kim
- Department
of Mechanical Engineering, and ‡Department of Biomedical Engineering, Ulsan National Institute of Science and Technology, 50 UNIST-gil, Ulsan 44919, Republic of Korea
| | - Juyeol Bae
- Department
of Mechanical Engineering, and ‡Department of Biomedical Engineering, Ulsan National Institute of Science and Technology, 50 UNIST-gil, Ulsan 44919, Republic of Korea
| | - Taesung Kim
- Department
of Mechanical Engineering, and ‡Department of Biomedical Engineering, Ulsan National Institute of Science and Technology, 50 UNIST-gil, Ulsan 44919, Republic of Korea
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10
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Hou X, Zhang YS, Trujillo-de Santiago G, Alvarez MM, Ribas J, Jonas SJ, Weiss PS, Andrews AM, Aizenberg J, Khademhosseini A. Interplay between materials and microfluidics. NATURE REVIEWS. MATERIALS 2017; 2:17016. [PMID: 38993477 PMCID: PMC11237287 DOI: 10.1038/natrevmats.2017.16] [Citation(s) in RCA: 176] [Impact Index Per Article: 25.1] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/13/2024]
Abstract
Developments in the field of microfluidics have triggered technological revolutions in many disciplines, including chemical synthesis, electronics, diagnostics, single-cell analysis, micro- and nanofabrication, and pharmaceutics. In many of these areas, rapid growth is driven by the increasing synergy between fundamental materials development and new microfluidic capabilities. In this Review, we critically evaluate both how recent advances in materials fabrication have expanded the frontiers of microfluidic platforms and how the improved microfluidic capabilities are, in turn, furthering materials design. We discuss how various inorganic and organic materials enable the fabrication of systems with advanced mechanical, optical, chemical, electrical and biointerfacial properties - in particular, when these materials are combined into new hybrids and modular configurations. The increasing sophistication of microfluidic techniques has also expanded the range of resources available for the fabrication of new materials, including particles and fibres with specific functionalities, 3D (bio)printed composites and organoids. Together, these advances lead to complex, multifunctional systems, which have many interesting potential applications, especially in the biomedical and bioengineering domains. Future exploration of the interactions between materials science and microfluidics will continue to enrich the diversity of applications across engineering as well as the physical and biomedical sciences.
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Affiliation(s)
- Xu Hou
- Biomaterials Innovation Research Center, Division of Engineering in Medicine, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Cambridge, Massachusetts 02139, USA
- Harvard-MIT Division of Health Sciences and Technology, Cambridge, Massachusetts 02139, USA
- College of Chemistry and Chemical Engineering, Xiamen University
- College of Physical Science and Technology, Xiamen University
- Pen-Tung Sah Institute of Micro-Nano Science and Technology, State Key Laboratory of Physical Chemistry of Solid Surfaces, Collaborative Innovation Center of Chemistry for Energy Materials, Xiamen University, Xiamen, Fujian 361005, China
| | - Yu Shrike Zhang
- Biomaterials Innovation Research Center, Division of Engineering in Medicine, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Cambridge, Massachusetts 02139, USA
- Harvard-MIT Division of Health Sciences and Technology, Cambridge, Massachusetts 02139, USA
- Wyss Institute for Biologically Inspired Engineering, Harvard University, Cambridge, Massachusetts 02138, USA
| | - Grissel Trujillo-de Santiago
- Biomaterials Innovation Research Center, Division of Engineering in Medicine, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Cambridge, Massachusetts 02139, USA
- Harvard-MIT Division of Health Sciences and Technology, Cambridge, Massachusetts 02139, USA
- Microsystems Technologies Laboratories, Massachusetts Institute of Technology (MIT), Cambridge, Massachusetts 02139, USA
- Centro de Biotecnología-FEMSA, Tecnológico de Monterrey at Monterrey, CP 64849, Monterrey, Nuevo León, México
| | - Mario Moisés Alvarez
- Biomaterials Innovation Research Center, Division of Engineering in Medicine, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Cambridge, Massachusetts 02139, USA
- Harvard-MIT Division of Health Sciences and Technology, Cambridge, Massachusetts 02139, USA
- Microsystems Technologies Laboratories, Massachusetts Institute of Technology (MIT), Cambridge, Massachusetts 02139, USA
- Centro de Biotecnología-FEMSA, Tecnológico de Monterrey at Monterrey, CP 64849, Monterrey, Nuevo León, México
| | - João Ribas
- Biomaterials Innovation Research Center, Division of Engineering in Medicine, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Cambridge, Massachusetts 02139, USA
- Harvard-MIT Division of Health Sciences and Technology, Cambridge, Massachusetts 02139, USA
- Doctoral Programme in Experimental Biology and Biomedicine, Institute for Interdisciplinary Research, University of Coimbra, Coimbra 3030-789, Portugal
| | - Steven J Jonas
- Department of Pediatrics, David Geffen School of Medicine, Eli and Edythe Broad Center of Regenerative Medicine and Stem Cell Research, and Children's Discovery and Innovation Institute, University of California, Los Angeles
- California NanoSystems Institute and Departments of Chemistry and Biochemistry, and of Materials Science and Engineering, University of California, Los Angeles
| | - Paul S Weiss
- Wyss Institute for Biologically Inspired Engineering, Harvard University, Cambridge, Massachusetts 02138, USA
- California NanoSystems Institute and Departments of Chemistry and Biochemistry, and of Materials Science and Engineering, University of California, Los Angeles
| | - Anne M Andrews
- California NanoSystems Institute and Departments of Psychiatry and Biobehavioral Sciences, and of Chemistry and Biochemistry, University of California, Los Angeles, California 90095, USA
| | - Joanna Aizenberg
- Wyss Institute for Biologically Inspired Engineering, Harvard University, Cambridge, Massachusetts 02138, USA
- John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts 02138, USA
| | - Ali Khademhosseini
- Biomaterials Innovation Research Center, Division of Engineering in Medicine, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Cambridge, Massachusetts 02139, USA
- Harvard-MIT Division of Health Sciences and Technology, Cambridge, Massachusetts 02139, USA
- Microsystems Technologies Laboratories, Massachusetts Institute of Technology (MIT), Cambridge, Massachusetts 02139, USA
- Department of Bioindustrial Technologies, College of Animal Bioscience and Technology, Konkuk University, Seoul 143-701, Republic of Korea
- Department of Physics, King Abdulaziz University, Jeddah 21589, Saudi Arabia
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11
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Kelley SO. New Technologies for Rapid Bacterial Identification and Antibiotic Resistance Profiling. SLAS Technol 2016; 22:113-121. [PMID: 27879409 DOI: 10.1177/2211068216680207] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
Conventional approaches to bacterial identification and drug susceptibility testing typically rely on culture-based approaches that take 2 to 7 days to return results. The long turnaround times contribute to the spread of infectious disease, negative patient outcomes, and the misuse of antibiotics that can contribute to antibiotic resistance. To provide new solutions enabling faster bacterial analysis, a variety of approaches are under development that leverage single-cell analysis, microfluidic concentration and detection strategies, and ultrasensitive readout mechanisms. This review discusses recent advances in this area and the potential of new technologies to enable more effective management of infectious disease.
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Affiliation(s)
- Shana O Kelley
- 1 Department of Pharmaceutical Sciences, Leslie Dan Faculty of Pharmacy, University of Toronto, Toronto, ON, Canada.,2 Department of Chemistry, Faculty of Arts and Science, University of Toronto, Toronto, ON, Canada.,3 Institute for Biomaterials and Biomedical Engineering, University of Toronto, Toronto, ON, Canada.,4 Department of Biochemistry, Faculty of Medicine, University of Toronto, Toronto, ON, Canada
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12
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Dai J, Hamon M, Jambovane S. Microfluidics for Antibiotic Susceptibility and Toxicity Testing. Bioengineering (Basel) 2016; 3:bioengineering3040025. [PMID: 28952587 PMCID: PMC5597268 DOI: 10.3390/bioengineering3040025] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2016] [Revised: 09/30/2016] [Accepted: 09/30/2016] [Indexed: 12/23/2022] Open
Abstract
The recent emergence of antimicrobial resistance has become a major concern for worldwide policy makers as very few new antibiotics have been developed in the last twenty-five years. To prevent the death of millions of people worldwide, there is an urgent need for a cheap, fast and accurate set of tools and techniques that can help to discover and develop new antimicrobial drugs. In the past decade, microfluidic platforms have emerged as potential systems for conducting pharmacological studies. Recent studies have demonstrated that microfluidic platforms can perform rapid antibiotic susceptibility tests to evaluate antimicrobial drugs’ efficacy. In addition, the development of cell-on-a-chip and organ-on-a-chip platforms have enabled the early drug testing, providing more accurate insights into conventional cell cultures on the drug pharmacokinetics and toxicity, at the early and cheaper stage of drug development, i.e., prior to animal and human testing. In this review, we focus on the recent developments of microfluidic platforms for rapid antibiotics susceptibility testing, investigating bacterial persistence and non-growing but metabolically active (NGMA) bacteria, evaluating antibiotic effectiveness on biofilms and combinatorial effect of antibiotics, as well as microfluidic platforms that can be used for in vitro antibiotic toxicity testing.
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Affiliation(s)
- Jing Dai
- Department of Electrical and Computer Engineering, Texas A&M University, College Station, TX 77843, USA.
| | - Morgan Hamon
- Renal Regeneration Laboratory, VAGLAHS at Sepulveda, North Hills, CA 91343, USA.
- David Geffen School of Medicine, University of California at Los Angeles, Los Angeles, CA 90095, USA.
| | - Sachin Jambovane
- Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory (PNNL), Richland, WA 99354, USA.
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13
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Baker JD, Kysela DT, Zhou J, Madren SM, Wilkens AS, Brun YV, Jacobson SC. Programmable, Pneumatically Actuated Microfluidic Device with an Integrated Nanochannel Array To Track Development of Individual Bacteria. Anal Chem 2016; 88:8476-83. [PMID: 27314919 DOI: 10.1021/acs.analchem.6b00889] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
We describe a microfluidic device with an integrated nanochannel array to trap individual bacteria and monitor growth and reproduction of lineages over multiple generations. Our poly(dimethylsiloxane) device comprises a pneumatically actuated nanochannel array that includes 1280 channels with widths from 600 to 1000 nm to actively trap diverse bacteria. Integrated pumps and valves perform on-chip fluid and cell manipulations that provide dynamic control of cell loading and nutrient flow, permitting chemostatic growth for extended periods of time (typically 12 to 20 h). Nanochannels confine bacterial growth to a single dimension, facilitating high-resolution, time-lapse imaging and tracking of individual cells. We use the device to monitor the growth of single bacterial cells that undergo symmetric (Bacillus subtilis) and asymmetric (Caulobacter crescentus) division and reconstruct their lineages to correlate growth measurements through time and among related cells. Furthermore, we monitor the motility state of single B. subtilis cells across multiple generations by the expression of a fluorescent reporter protein and observe that the state of the epigenetic switch is correlated over five generations. Our device allows imaging of cellular lineages with high spatiotemporal resolution to facilitate the analysis of biological processes spanning multiple generations.
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Affiliation(s)
- Joshua D Baker
- Department of Chemistry and ‡Department of Biology, Indiana University , Bloomington, Indiana 47405, United States
| | - David T Kysela
- Department of Chemistry and ‡Department of Biology, Indiana University , Bloomington, Indiana 47405, United States
| | - Jinsheng Zhou
- Department of Chemistry and ‡Department of Biology, Indiana University , Bloomington, Indiana 47405, United States
| | - Seth M Madren
- Department of Chemistry and ‡Department of Biology, Indiana University , Bloomington, Indiana 47405, United States
| | - Andrew S Wilkens
- Department of Chemistry and ‡Department of Biology, Indiana University , Bloomington, Indiana 47405, United States
| | - Yves V Brun
- Department of Chemistry and ‡Department of Biology, Indiana University , Bloomington, Indiana 47405, United States
| | - Stephen C Jacobson
- Department of Chemistry and ‡Department of Biology, Indiana University , Bloomington, Indiana 47405, United States
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15
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Geng T, Bredeweg EL, Szymanski CJ, Liu B, Baker SE, Orr G, Evans JE, Kelly RT. Compartmentalized microchannel array for high-throughput analysis of single cell polarized growth and dynamics. Sci Rep 2015; 5:16111. [PMID: 26530004 PMCID: PMC4632079 DOI: 10.1038/srep16111] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2015] [Accepted: 10/08/2015] [Indexed: 12/01/2022] Open
Abstract
Interrogating polarized growth is technologically challenging due to extensive cellular branching and uncontrollable environmental conditions in conventional assays. Here we present a robust and high-performance microfluidic system that enables observations of polarized growth with enhanced temporal and spatial control over prolonged periods. The system has built-in tunability and versatility to accommodate a variety of scientific applications requiring precisely controlled environments. Using the model filamentous fungus, Neurospora crassa, our microfluidic system enabled direct visualization and analysis of cellular heterogeneity in a clonal fungal cell population, nuclear distribution and dynamics at the subhyphal level, and quantitative dynamics of gene expression with single hyphal compartment resolution in response to carbon source starvation and exchange. Although the microfluidic device is demonstrated on filamentous fungi, the technology is immediately extensible to a wide array of other biosystems that exhibit similar polarized cell growth, with applications ranging from bioenergy production to human health.
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Affiliation(s)
- Tao Geng
- Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, Richland, WA, USA
| | - Erin L Bredeweg
- Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, Richland, WA, USA
| | - Craig J Szymanski
- Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, Richland, WA, USA
| | - Bingwen Liu
- Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, Richland, WA, USA
| | - Scott E Baker
- Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, Richland, WA, USA
| | - Galya Orr
- Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, Richland, WA, USA
| | - James E Evans
- Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, Richland, WA, USA
| | - Ryan T Kelly
- Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, Richland, WA, USA
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Li B, Qiu Y, Glidle A, Cooper J, Shi H, Yin H. Single cell growth rate and morphological dynamics revealing an "opportunistic" persistence. Analyst 2015; 139:3305-13. [PMID: 24733150 DOI: 10.1039/c4an00170b] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Bacteria persistence is a well-known phenomenon, where a small fraction of cells in an isogenic population are able to survive high doses of antibiotic treatment. Since the persistence is often associated with single cell behaviour, the ability to study the dynamic response of individual cells to antibiotics is critical. In this work, we developed a gradient microfluidic system that enables long-term tracking of single cell morphology under a wide range of inhibitor concentrations. From time-lapse images, we calculated bacterial growth rates based on the variations in cell mass and in cell number. Using E. coli and Comamonas denitrificans to amoxicillin inhibition as model systems, we found the IC50 determined via both methods are in a good agreement. Importantly, the growth rates together with morphological dynamics of individual cells has led to the discovery of a new form of persistence to amoxicillin. Normal cells that are sensitive to amoxicillin gain persistence or recover from the killing process, if they have had an opportunity to utilise the cytoplasm released from lysed cells close-by. We term this acquired persistence in normal growing cells "opportunistic persistence". This finding might shed new insights into biofilm resistance and the effect of antibiotics on environmental microbes.
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Affiliation(s)
- Bing Li
- Environmental Simulation and Pollution Control State-key Joint Laboratory, School of Environment, Tsinghua University, Beijing 100084, China.
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Long Z, Olliver A, Brambilla E, Sclavi B, Lagomarsino MC, Dorfman KD. Measuring bacterial adaptation dynamics at the single-cell level using a microfluidic chemostat and time-lapse fluorescence microscopy. Analyst 2014; 139:5254-62. [PMID: 25137302 DOI: 10.1039/c4an00877d] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We monitored the dynamics of cell dimensions and reporter GFP expression in individual E. coli cells growing in a microfluidic chemostat using time-lapse fluorescence microscopy. This combination of techniques allows us to study the dynamical responses of single bacterial cells to nutritional shift-down or shift-up for longer times and with more precision over the chemical environment than similar experiments performed on conventional agar pads. We observed two E. coli strains containing different promoter-reporter gene constructs and measured how both their cell dimensions and the GFP expression change after nutritional upshift and downshift. As expected, both strains have similar adaptation dynamics for cell size rearrangement. However, the strain with a ribosomal RNA promoter dependent reporter has a faster GFP production rate than the strain with a constitutive promoter reporter. As a result, the mean GFP concentration in the former strain changes rapidly with the nutritional shift, while that in the latter strain remains relatively stable. These findings characterize the present microfluidic chemostat as a versatile platform for measuring single-cell bacterial dynamics and physiological transitions.
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Affiliation(s)
- Zhicheng Long
- Department of Chemical Engineering and Materials Science, University of Minnesota - Twin Cities, 421 Washington Ave. SE, Minneapolis, MN 55455, USA.
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Li B, Qiu Y, Glidle A, McIlvenna D, Luo Q, Cooper J, Shi HC, Yin H. Gradient microfluidics enables rapid bacterial growth inhibition testing. Anal Chem 2014; 86:3131-7. [PMID: 24548044 PMCID: PMC3988682 DOI: 10.1021/ac5001306] [Citation(s) in RCA: 64] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2013] [Accepted: 02/18/2014] [Indexed: 11/28/2022]
Abstract
Bacterial growth inhibition tests have become a standard measure of the adverse effects of inhibitors for a wide range of applications, such as toxicity testing in the medical and environmental sciences. However, conventional well-plate formats for these tests are laborious and provide limited information (often being restricted to an end-point assay). In this study, we have developed a microfluidic system that enables fast quantification of the effect of an inhibitor on bacteria growth and survival, within a single experiment. This format offers a unique combination of advantages, including long-term continuous flow culture, generation of concentration gradients, and single cell morphology tracking. Using Escherichia coli and the inhibitor amoxicillin as one model system, we show excellent agreement between an on-chip single cell-based assay and conventional methods to obtain quantitative measures of antibiotic inhibition (for example, minimum inhibition concentration). Furthermore, we show that our methods can provide additional information, over and above that of the standard well-plate assay, including kinetic information on growth inhibition and measurements of bacterial morphological dynamics over a wide range of inhibitor concentrations. Finally, using a second model system, we show that this chip-based systems does not require the bacteria to be labeled and is well suited for the study of naturally occurring species. We illustrate this using Nitrosomonas europaea, an environmentally important bacteria, and show that the chip system can lead to a significant reduction in the period required for growth and inhibition measurements (<4 days, compared to weeks in a culture flask).
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Affiliation(s)
- Bing Li
- Environmental
Simulation and Pollution Control State-Key Joint Laboratory, School
of Environment, Tsinghua University, Beijing 100084, China
| | - Yong Qiu
- Environmental
Simulation and Pollution Control State-Key Joint Laboratory, School
of Environment, Tsinghua University, Beijing 100084, China
| | - Andrew Glidle
- Division
of Biomedical Engineering, School of Engineering, University of Glasgow, Glasgow G12 8LT, U.K.
| | - David McIlvenna
- Division
of Biomedical Engineering, School of Engineering, University of Glasgow, Glasgow G12 8LT, U.K.
| | - Qian Luo
- State
Key Laboratory of Environmental Aquatic Chemistry, Research Center
for Eco-Environmental Sciences, Chinese
Academy of Sciences, Beijing 100085, China
| | - Jon Cooper
- Division
of Biomedical Engineering, School of Engineering, University of Glasgow, Glasgow G12 8LT, U.K.
| | - Han-Chang Shi
- Environmental
Simulation and Pollution Control State-Key Joint Laboratory, School
of Environment, Tsinghua University, Beijing 100084, China
| | - Huabing Yin
- Division
of Biomedical Engineering, School of Engineering, University of Glasgow, Glasgow G12 8LT, U.K.
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Cattoni DI, Fiche JB, Valeri A, Mignot T, Nöllmann M. Super-resolution imaging of bacteria in a microfluidics device. PLoS One 2013; 8:e76268. [PMID: 24146850 PMCID: PMC3797773 DOI: 10.1371/journal.pone.0076268] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2013] [Accepted: 08/22/2013] [Indexed: 11/18/2022] Open
Abstract
Bacteria have evolved complex, highly-coordinated, multi-component cellular engines to achieve high degrees of efficiency, accuracy, adaptability, and redundancy. Super-resolution fluorescence microscopy methods are ideally suited to investigate the internal composition, architecture, and dynamics of molecular machines and large cellular complexes. These techniques require the long-term stability of samples, high signal-to-noise-ratios, low chromatic aberrations and surface flatness, conditions difficult to meet with traditional immobilization methods. We present a method in which cells are functionalized to a microfluidics device and fluorophores are injected and imaged sequentially. This method has several advantages, as it permits the long-term immobilization of cells and proper correction of drift, avoids chromatic aberrations caused by the use of different filter sets, and allows for the flat immobilization of cells on the surface. In addition, we show that different surface chemistries can be used to image bacteria at different time-scales, and we introduce an automated cell detection and image analysis procedure that can be used to obtain cell-to-cell, single-molecule localization and dynamic heterogeneity as well as average properties at the super-resolution level.
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Affiliation(s)
- Diego I. Cattoni
- Centre de Biochimie Structurale, Centre National de la Recherche Scientifique, Unité Mixte de Recherche 5048, Montpellier, France
- Institut Nationale de la Santé et la Recherche Médicale, Unité 1054, Montpellier, France
- Universités Montpellier I et II, Montpellier, France
| | - Jean-Bernard Fiche
- Centre de Biochimie Structurale, Centre National de la Recherche Scientifique, Unité Mixte de Recherche 5048, Montpellier, France
- Institut Nationale de la Santé et la Recherche Médicale, Unité 1054, Montpellier, France
- Universités Montpellier I et II, Montpellier, France
| | - Alessandro Valeri
- Centre de Biochimie Structurale, Centre National de la Recherche Scientifique, Unité Mixte de Recherche 5048, Montpellier, France
- Institut Nationale de la Santé et la Recherche Médicale, Unité 1054, Montpellier, France
- Universités Montpellier I et II, Montpellier, France
| | - Tâm Mignot
- Laboratoire de Chimie Bactérienne, Centre National de la Recherche Scientifique, Aix-Marseille University, Unité Mixte de Recherche 7283, Marseille, France
| | - Marcelo Nöllmann
- Centre de Biochimie Structurale, Centre National de la Recherche Scientifique, Unité Mixte de Recherche 5048, Montpellier, France
- Institut Nationale de la Santé et la Recherche Médicale, Unité 1054, Montpellier, France
- Universités Montpellier I et II, Montpellier, France
- * E-mail:
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Nghe P, Boulineau S, Gude S, Recouvreux P, van Zon JS, Tans SJ. Microfabricated polyacrylamide devices for the controlled culture of growing cells and developing organisms. PLoS One 2013; 8:e75537. [PMID: 24086559 PMCID: PMC3782435 DOI: 10.1371/journal.pone.0075537] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2013] [Accepted: 08/19/2013] [Indexed: 01/09/2023] Open
Abstract
The ability to spatially confine living cells or small organisms while dynamically controlling their aqueous environment is important for a host of microscopy applications. Here, we show how polyacrylamide layers can be patterned to construct simple microfluidic devices for this purpose. We find that polyacrylamide gels can be molded like PDMS into micron-scale structures that can enclose organisms, while being permeable to liquids, and transparent to allow for microscopic observation. We present a range of chemostat-like devices to observe bacterial and yeast growth, and C. elegans nematode development. The devices can integrate PDMS layers and allow for temporal control of nutrient conditions and the presence of drugs on a minute timescale. We show how spatial confinement of motile C. elegans enables for time-lapse microscopy in a parallel fashion.
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Rodriguez-Rodriguez R, Muñoz-Berbel X, Demming S, Büttgenbach S, Herrera MD, Llobera A. Cell-based microfluidic device for screening anti-proliferative activity of drugs in vascular smooth muscle cells. Biomed Microdevices 2013; 14:1129-40. [PMID: 22773184 DOI: 10.1007/s10544-012-9679-y] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
This paper presents a microfluidic device consisting of five parallel microchambers with integrated readout-grid for the screening of anti-proliferative activity of drugs in vascular smooth muscle cells (VSMC). A two-level SU-8 master was fabricated and replicated with poly(dimethylsiloxane), PDMS, using standard soft-lithographic methods. The relative small height (4-10 μm) of the integrated grid allowed the identification of single-cells or cell groups and the monitoring of their motility, morphology and size with time, without disturbing their proliferation pattern. This is of particular interest when considering VSMC which, apart of being crucial in the atherosclerotic process, do not proliferate in a single layer but in a non-homogenous hill and valley phenotype. The performance of the microfluidic device has been validated by comparison with conventional culturing methods, proving that the cell proliferation remains unaffected by the microchamber structure (with the integrated grid) and the experimental conditions. Finally, the microfluidic device was also used to evaluate the anti-proliferative activity of curcumin and colchicine in VSMC. With this cellular type, the anti-proliferative activity of curcumin (IC(50) =35 ± 5 μM) was found to be much lower than colchicine (IC(50) =3.2 ± 1.2 μM). These results demonstrate the good performance of the microfluidic device in the evaluation of the anti-proliferative activity (or cytotoxicity) of drugs.
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Affiliation(s)
- R Rodriguez-Rodriguez
- School of Pharmacy, Department of Pharmacology, Universidad de Sevilla, Sevilla, Spain
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22
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A microfluidic photolithography for controlled encapsulation of single cells inside hydrogel microstructures. Sci China Chem 2012. [DOI: 10.1007/s11426-012-4538-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
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