1
|
Liao X, Zhang Y, Zhang Q, Zhou J, Ding T, Feng J. Advancing point-of-care microbial pathogens detection by material-functionalized microfluidic systems. Trends Food Sci Technol 2023. [DOI: 10.1016/j.tifs.2023.03.022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/30/2023]
|
2
|
Moustafa TE, Polanco ER, Belote RL, Judson-Torres RL, Zangle TA. Fabrication and validation of an LED array microscope for multimodal, quantitative imaging. HARDWAREX 2023; 13:e00399. [PMID: 36756350 PMCID: PMC9900438 DOI: 10.1016/j.ohx.2023.e00399] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/15/2022] [Revised: 01/11/2023] [Accepted: 01/21/2023] [Indexed: 06/18/2023]
Abstract
The combination of multiple imaging modalities in a single microscopy system can enable new insights into biological processes. In this work, we describe the construction and rigorous characterization of a custom microscope with multimodal imaging in a single, cost-effective system. Our design utilizes advances in LED technology, robotics, and open-source software, along with existing optical components and precision optomechanical parts to offer a modular and versatile design. This microscope is operated using software written in Arduino and Python and has the ability to run multi-day automated imaging experiments when placed inside of a cell culture incubator. Additionally, we provide and demonstrate methods to validate images taken in brightfield and darkfield, along with validation and optimization for differential phase contrast (DPC) quantitative phase imaging.
Collapse
Affiliation(s)
- Tarek E. Moustafa
- Department of Chemical Engineering, University of Utah, Salt Lake City, UT, USA
| | - Edward R. Polanco
- Department of Chemical Engineering, University of Utah, Salt Lake City, UT, USA
| | - Rachel L. Belote
- Huntsman Cancer Institute, University of Utah, Salt Lake City, UT, USA
| | - Robert L. Judson-Torres
- Huntsman Cancer Institute, University of Utah, Salt Lake City, UT, USA
- Department of Dermatology, University of Utah, Salt Lake City, UT, USA
| | - Thomas A. Zangle
- Department of Chemical Engineering, University of Utah, Salt Lake City, UT, USA
- Huntsman Cancer Institute, University of Utah, Salt Lake City, UT, USA
| |
Collapse
|
3
|
Buchanan BC, Yoon JY. Microscopic Imaging Methods for Organ-on-a-Chip Platforms. MICROMACHINES 2022; 13:328. [PMID: 35208453 PMCID: PMC8879989 DOI: 10.3390/mi13020328] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/13/2022] [Revised: 02/15/2022] [Accepted: 02/15/2022] [Indexed: 02/06/2023]
Abstract
Microscopic imaging is essential and the most popular method for in situ monitoring and evaluating the outcome of various organ-on-a-chip (OOC) platforms, including the number and morphology of mammalian cells, gene expression, protein secretions, etc. This review presents an overview of how various imaging methods can be used to image organ-on-a-chip platforms, including transillumination imaging (including brightfield, phase-contrast, and holographic optofluidic imaging), fluorescence imaging (including confocal fluorescence and light-sheet fluorescence imaging), and smartphone-based imaging (including microscope attachment-based, quantitative phase, and lens-free imaging). While various microscopic imaging methods have been demonstrated for conventional microfluidic devices, a relatively small number of microscopic imaging methods have been demonstrated for OOC platforms. Some methods have rarely been used to image OOCs. Specific requirements for imaging OOCs will be discussed in comparison to the conventional microfluidic devices and future directions will be introduced in this review.
Collapse
Affiliation(s)
| | - Jeong-Yeol Yoon
- Department of Biomedical Engineering, The University of Arizona, Tucson, AZ 85721, USA;
| |
Collapse
|
4
|
Samal P, Gubbins E, van Blitterswijk C, Truckenmüller R, Giselbrecht S. Thin fluorinated polymer film microcavity arrays for 3D cell culture and label-free automated feature extraction. Biomater Sci 2021; 9:7838-7850. [PMID: 34671787 DOI: 10.1039/d1bm00718a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
There is an increasing need for automated label-free morphometric analysis using brightfield microscopy images of 3D cell culture systems. This requires automated feature detection which can be achieved by improving the image contrast, e.g. by reducing the refractive index mismatch in the light path. Here, a novel microcavity platform fabricated using microthermoforming of thin fluorinated ethylene-propylene (FEP) films which match the refractive index of cell culture medium and provide a homogenous background signal intensity is described. FEP is chemically inert, mechanically stable and has been used as a substrate for light sheet microscopy. The microcavities promote formation of mouse embryonic stem cell (mESC) aggregates, which show axial elongation and germ layer specification similar to embryonic development. A label-free feature extraction pipeline based on a machine-learning plugin for FIJI is used to extract morphometric features from time-lapse imaging in a highly robust and reproducible manner. Lastly, the pipeline is utilized for testing the effect of the drug Latrunculin A on the mESC aggregates, highlighting the platform's potential for high-content screening (HCS) in drug discovery. This new microengineered tool is an important step towards label-free imaging of free-floating stem cell aggregates and paves the way for high-content drug testing and translational studies.
Collapse
Affiliation(s)
- Pinak Samal
- MERLN Institute for Technology-Inspired Regenerative Medicine, Maastricht University, Universiteitssingel 40, 6229 ER Maastricht, The Netherlands.
| | - Eva Gubbins
- MERLN Institute for Technology-Inspired Regenerative Medicine, Maastricht University, Universiteitssingel 40, 6229 ER Maastricht, The Netherlands.
| | - Clemens van Blitterswijk
- MERLN Institute for Technology-Inspired Regenerative Medicine, Maastricht University, Universiteitssingel 40, 6229 ER Maastricht, The Netherlands.
| | - Roman Truckenmüller
- MERLN Institute for Technology-Inspired Regenerative Medicine, Maastricht University, Universiteitssingel 40, 6229 ER Maastricht, The Netherlands.
| | - Stefan Giselbrecht
- MERLN Institute for Technology-Inspired Regenerative Medicine, Maastricht University, Universiteitssingel 40, 6229 ER Maastricht, The Netherlands.
| |
Collapse
|
5
|
Han X, Zhang Y, Tian J, Wu T, Li Z, Xing F, Fu S. Polymer‐based microfluidic devices: A comprehensive review on preparation and applications. POLYM ENG SCI 2021. [DOI: 10.1002/pen.25831] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Affiliation(s)
- Xue Han
- School of Physics and Optoelectronic Engineering Shandong University of Technology Zibo China
| | - Yonghui Zhang
- School of Physics and Optoelectronic Engineering Shandong University of Technology Zibo China
| | - Jingkun Tian
- School of Physics and Optoelectronic Engineering Shandong University of Technology Zibo China
| | - Tiange Wu
- School of Physics and Optoelectronic Engineering Shandong University of Technology Zibo China
| | - Zongwen Li
- School of Physics and Optoelectronic Engineering Shandong University of Technology Zibo China
| | - Fei Xing
- School of Physics and Optoelectronic Engineering Shandong University of Technology Zibo China
| | - Shenggui Fu
- School of Physics and Optoelectronic Engineering Shandong University of Technology Zibo China
| |
Collapse
|
6
|
Shakeri A, Khan S, Didar TF. Conventional and emerging strategies for the fabrication and functionalization of PDMS-based microfluidic devices. LAB ON A CHIP 2021; 21:3053-3075. [PMID: 34286800 DOI: 10.1039/d1lc00288k] [Citation(s) in RCA: 86] [Impact Index Per Article: 28.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Microfluidics is an emerging and multidisciplinary field that is of great interest to manufacturers in medicine, biotechnology, and chemistry, as it provides unique tools for the development of point-of-care diagnostics, organs-on-chip systems, and biosensors. Polymeric microfluidics, unlike glass and silicon, offer several advantages such as low-cost mass manufacturing and a wide range of beneficial material properties, which make them the material of choice for commercial applications and high-throughput systems. Among polymers used for the fabrication of microfluidic devices, polydimethylsiloxane (PDMS) still remains the most widely used material in academia due to its advantageous properties, such as excellent transparency and biocompatibility. However, commercialization of PDMS has been a challenge mostly due to the high cost of the current fabrication strategies. Moreover, specific surface modification and functionalization steps are required to tailor the surface chemistry of PDMS channels (e.g. biomolecule immobilization, surface hydrophobicity and antifouling properties) with respect to the desired application. While significant research has been reported in the field of PDMS microfluidics, functionalization of PDMS surfaces remains a critical step in the fabrication process that is difficult to navigate. This review first offers a thorough illustration of existing fabrication methods for PDMS-based microfluidic devices, providing several recent advancements in this field with the aim of reducing the cost and time for mass production of these devices. Next, various conventional and emerging approaches for engineering the surface chemistry of PDMS are discussed in detail. We provide a wide range of functionalization techniques rendering PDMS microchannels highly biocompatible for physical or covalent immobilization of various biological entities while preventing non-specific interactions.
Collapse
Affiliation(s)
- Amid Shakeri
- Department of Mechanical Engineering, McMaster University, 1280 Main Street West, Hamilton, ON L8S 4L7, Canada.
| | - Shadman Khan
- School of Biomedical Engineering, McMaster University, 1280 Main Street West, Hamilton, ON L8S 4L8, Canada
| | - Tohid F Didar
- Department of Mechanical Engineering, McMaster University, 1280 Main Street West, Hamilton, ON L8S 4L7, Canada.
- School of Biomedical Engineering, McMaster University, 1280 Main Street West, Hamilton, ON L8S 4L8, Canada
| |
Collapse
|
7
|
Microfabricated Devices for Confocal Microscopy on Biological Samples. Methods Mol Biol 2021. [PMID: 34028712 DOI: 10.1007/978-1-0716-1402-0_4] [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
Microfabricated devices have found applications in a range of biomedical research problems in recent years, with thousands of research papers published and multiple commercial devices now available. This chapter is intended to provide an overview of the available options for devices compatible with confocal microscopy, including an overview of fabrication techniques and some examples of device use. Although there are times when off-the-shelf devices are well suited for the problem at hand, in some cases customized devices are necessary or more convenient. Protocols for researchers who wish to make their own devices are outlined below; although fabricating templates for devices requires some specialized equipment, making PDMS or hydrogel devices from templates can be done in a standard laboratory setting.
Collapse
|
8
|
Han X, Su Y, White H, O'Neill KM, Morgan NY, Christensen R, Potarazu D, Vishwasrao HD, Xu S, Sun Y, Huang SY, Moyle MW, Dai Q, Pommier Y, Giniger E, Albrecht DR, Probst R, Shroff H. A polymer index-matched to water enables diverse applications in fluorescence microscopy. LAB ON A CHIP 2021; 21:1549-1562. [PMID: 33629685 PMCID: PMC8058278 DOI: 10.1039/d0lc01233e] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
We demonstrate diffraction-limited and super-resolution imaging through thick layers (tens-hundreds of microns) of BIO-133, a biocompatible, UV-curable, commercially available polymer with a refractive index (RI) matched to water. We show that cells can be directly grown on BIO-133 substrates without the need for surface passivation and use this capability to perform extended time-lapse volumetric imaging of cellular dynamics 1) at isotropic resolution using dual-view light-sheet microscopy, and 2) at super-resolution using instant structured illumination microscopy. BIO-133 also enables immobilization of 1) Drosophila tissue, allowing us to track membrane puncta in pioneer neurons, and 2) Caenorhabditis elegans, which allows us to image and inspect fine neural structure and to track pan-neuronal calcium activity over hundreds of volumes. Finally, BIO-133 is compatible with other microfluidic materials, enabling optical and chemical perturbation of immobilized samples, as we demonstrate by performing drug and optogenetic stimulation on cells and C. elegans.
Collapse
Affiliation(s)
- Xiaofei Han
- Laboratory of High Resolution Optical Imaging, National Institute of Biomedical Imaging and Bioengineering, National Institutes of Health, Bethesda, MD 20892, USA. and Department of Automation, Tsinghua University, Beijing, 100084, China.
| | - Yijun Su
- Laboratory of High Resolution Optical Imaging, National Institute of Biomedical Imaging and Bioengineering, National Institutes of Health, Bethesda, MD 20892, USA. and Advanced Imaging and Microscopy Resource, National Institutes of Health, Bethesda, MD 20892, USA
| | - Hamilton White
- Department of Biomedical Engineering, Worcester Polytechnic Institute, 100 Institute Road, Worcester, MA 01609, USA. and Department of Neurobiology, University of Massachusetts Medical School, Worcester, MA 01655, USA
| | - Kate M O'Neill
- National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892, USA and Institute for Physical Science and Technology, University of Maryland College Park, College Park, MD 20742, USA
| | - Nicole Y Morgan
- National Institute of Biomedical Imaging and Bioengineering, National Institutes of Health, Bethesda, MD 20892, USA
| | - Ryan Christensen
- Laboratory of High Resolution Optical Imaging, National Institute of Biomedical Imaging and Bioengineering, National Institutes of Health, Bethesda, MD 20892, USA.
| | - Deepika Potarazu
- Laboratory of High Resolution Optical Imaging, National Institute of Biomedical Imaging and Bioengineering, National Institutes of Health, Bethesda, MD 20892, USA.
| | - Harshad D Vishwasrao
- Advanced Imaging and Microscopy Resource, National Institutes of Health, Bethesda, MD 20892, USA
| | - Stephen Xu
- Laboratory of High Resolution Optical Imaging, National Institute of Biomedical Imaging and Bioengineering, National Institutes of Health, Bethesda, MD 20892, USA.
| | - Yilun Sun
- Developmental Therapeutics Branch and Laboratory of Molecular Pharmacology, Center for Cancer Research, National Institutes of Health, Bethesda, MD 20892, USA
| | - Shar-Yin Huang
- Developmental Therapeutics Branch and Laboratory of Molecular Pharmacology, Center for Cancer Research, National Institutes of Health, Bethesda, MD 20892, USA
| | - Mark W Moyle
- Department of Neuroscience and Department of Cell Biology, Yale University School of Medicine, New Haven, CT 06536, USA
| | - Qionghai Dai
- Department of Automation, Tsinghua University, Beijing, 100084, China.
| | - Yves Pommier
- Developmental Therapeutics Branch and Laboratory of Molecular Pharmacology, Center for Cancer Research, National Institutes of Health, Bethesda, MD 20892, USA
| | - Edward Giniger
- National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892, USA
| | - Dirk R Albrecht
- Department of Biomedical Engineering, Worcester Polytechnic Institute, 100 Institute Road, Worcester, MA 01609, USA. and Department of Biology and Biotechnology, Worcester Polytechnic Institute, 100 Institute Road, Worcester, MA 01609, USA
| | - Roland Probst
- ACUITYnano, Innovation in Biomedical Imaging, North Bethesda, MD 20850, USA
| | - Hari Shroff
- Laboratory of High Resolution Optical Imaging, National Institute of Biomedical Imaging and Bioengineering, National Institutes of Health, Bethesda, MD 20892, USA. and Advanced Imaging and Microscopy Resource, National Institutes of Health, Bethesda, MD 20892, USA and Marine Biological Laboratory Fellows Program, Woods Hole, MA 02543, USA
| |
Collapse
|
9
|
Fabrication and Bonding of Refractive Index Matched Microfluidics for Precise Measurements of Cell Mass. Polymers (Basel) 2021; 13:polym13040496. [PMID: 33562507 PMCID: PMC7915968 DOI: 10.3390/polym13040496] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2020] [Revised: 01/26/2021] [Accepted: 02/02/2021] [Indexed: 12/23/2022] Open
Abstract
The optical properties of polymer materials used for microfluidic device fabrication can impact device performance when used for optical measurements. In particular, conventional polymer materials used for microfluidic devices have a large difference in refractive index relative to aqueous media generally used for biomedical applications. This can create artifacts when used for microscopy-based assays. Fluorination can reduce polymer refractive index, but at the cost of reduced adhesion, creating issues with device bonding. Here, we present a novel fabrication technique for bonding microfluidic devices made of NOA1348, which is a fluorinated, UV-curable polymer with a refractive index similar to that of water, to a glass substrate. This technique is compatible with soft lithography techniques, making this approach readily integrated into existing microfabrication workflows. We also demonstrate that this material is compatible with quantitative phase imaging, which we used to validate the refractive index of the material post-fabrication. Finally, we demonstrate the use of this material with a novel image processing approach to precisely quantify the mass of cells in the microchannel without the use of cell segmentation or tracking. The novel image processing approach combined with this low refractive index material eliminates an important source of error, allowing for high-precision measurements of cell mass with a coefficient of variance of 1%.
Collapse
|
10
|
Sticker D, Geczy R, Häfeli UO, Kutter JP. Thiol-Ene Based Polymers as Versatile Materials for Microfluidic Devices for Life Sciences Applications. ACS APPLIED MATERIALS & INTERFACES 2020; 12:10080-10095. [PMID: 32048822 DOI: 10.1021/acsami.9b22050] [Citation(s) in RCA: 54] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
While there is a steady growth in the number of microfluidics applications, the search for an optimal material that delivers the diverse characteristics needed for the numerous tasks is still nowhere close to being settled. Often overlooked and still underrepresented, the thiol-ene family of polymer materials has an enormous potential for applications in organs-on-a-chip, droplet productions, microanalytics, and point of care testing. In this review, the main characteristics of the thiol-ene materials are given, and advantages and drawbacks with respect to their potential in microfluidic chip fabrication are critically assessed. Select applications, which exploit the versatility of the thiol-ene polymers, are presented and discussed. It is concluded that, in particular, the rapid prototyping possibility combined with the material's resulting mechanical strength, solvent resistance, and biocompatibility, as well as the inherently easy surface functionalization, are strong factors to make thiol-ene polymers strong contenders for promising future materials for many biological, clinical, and technical lab-on-a-chip applications.
Collapse
Affiliation(s)
- Drago Sticker
- Department of Pharmacy, Faculty of Health and Medical Sciences, University of Copenhagen, 2100 Copenhagen, Denmark
| | - Reka Geczy
- Department of Pharmacy, Faculty of Health and Medical Sciences, University of Copenhagen, 2100 Copenhagen, Denmark
- Faculty of Pharmaceutical Sciences, University of British Columbia, Vancouver, British Columbia V6T 1Z3, Canada
| | - Urs O Häfeli
- Department of Pharmacy, Faculty of Health and Medical Sciences, University of Copenhagen, 2100 Copenhagen, Denmark
- Faculty of Pharmaceutical Sciences, University of British Columbia, Vancouver, British Columbia V6T 1Z3, Canada
| | - Jörg P Kutter
- Department of Pharmacy, Faculty of Health and Medical Sciences, University of Copenhagen, 2100 Copenhagen, Denmark
| |
Collapse
|
11
|
Iacono ST, Jennings AR. Recent Studies on Fluorinated Silica Nanometer-Sized Particles. NANOMATERIALS (BASEL, SWITZERLAND) 2019; 9:E684. [PMID: 31052570 PMCID: PMC6567222 DOI: 10.3390/nano9050684] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/09/2019] [Revised: 04/18/2019] [Accepted: 04/23/2019] [Indexed: 11/16/2022]
Abstract
Since initially being reported, fluorinated silica nanometer-sized particles (F-SiNPs) have gained much interest in the scientific community, due to their unique properties. These properties, include, low surface energies, increased mechanical strength, thermal robustness, and chemical resistance, and are a direct result of the incorporation of fluorine with a nanometer-sized silica network. This review aims to summarize the synthetic methods that have, and are still, being utilized to prepare these specialized materials. Following this, applications for F-SiNPs, with an emphasis on recent examples, will be presented in further detail.
Collapse
Affiliation(s)
- Scott T Iacono
- Department of Chemistry and Chemistry Research Center, United States Air Force Academy, 2355 Fairchild Dr, Colorado Springs, CO 80840, USA.
| | - Abby R Jennings
- Department of Chemistry and Chemistry Research Center, United States Air Force Academy, 2355 Fairchild Dr, Colorado Springs, CO 80840, USA.
| |
Collapse
|
12
|
Polanco ER, Western N, Zangle TA. Fabrication of Refractive-index-matched Devices for Biomedical Microfluidics. J Vis Exp 2018:58296. [PMID: 30247465 PMCID: PMC6235158 DOI: 10.3791/58296] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
The use of microfluidic devices has emerged as a defining tool for biomedical applications. When combined with modern microscopy techniques, these devices can be implemented as part of a robust platform capable of making simultaneous complementary measurements. The primary challenge created by the combination of these two techniques is the mismatch in refractive index between the materials traditionally used to make microfluidic devices and the aqueous solutions typically used in biomedicine. This mismatch can create optical artifacts near the channel or device edges. One solution is to reduce the refractive index of the material used to fabricate the device by using a fluorinated polymer such as MY133-V2000 whose refractive index is similar to that of water (n = 1.33). Here, the construction of a microfluidic device made out of MY133-V2000 using soft lithography techniques is demonstrated, using O2 plasma in conjunction with an acrylic holder to increase the adhesion between the MY133-V2000 fabricated device and the polydimethylsiloxane (PDMS) substrate. The device is then tested by incubating it filled with cell culture media for 24 h to demonstrate the ability of the device to maintain cell culture conditions during the course of a typical imaging experiment. Finally, quantitative phase microscopy (QPM) is used to measure the distribution of mass within the live adherent cells in the microchannel. This way, the increased precision, enabled by fabricating the device from a low index of refraction polymer such as MY133-V2000 in lieu of traditional soft lithography materials such as PDMS, is demonstrated. Overall, this approach for fabricating microfluidic devices can be readily integrated into existing soft lithography workflows in order to reduce optical artifacts and increase measurement precision.
Collapse
Affiliation(s)
| | | | - Thomas A Zangle
- Department of Chemical Engineering, University of Utah; Huntsman Cancer Institute, University of Utah;
| |
Collapse
|