1
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Moon BU, Clime L, Hernandez-Castro JA, Brassard D, Nassif C, Malic L, Veres T. On-the-Fly Phase Transition and Density Changes of Aqueous Two-Phase Systems on a Centrifugal Microfluidic Platform. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2022; 38:79-85. [PMID: 34928624 DOI: 10.1021/acs.langmuir.1c01923] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
This paper describes on-the-fly physical property changes of aqueous two-phase systems (ATPS) in microfluidic devices. The properties and phases of the ATPS are modulated on-demand by using a centrifugal microfluidic device filled with poly(ethylene glycol) (PEG) and dextran (DEX) solutions. By use of the centrifugal force and active pneumatic controls provided by a centrifugal microfluidic platform (CMP), PEG-DEX mixtures are manipulated and processed inside simple thermoplastic microfluidic devices. First, we experimentally demonstrate an on-chip ATPS transition from two phases to a single phase and vice versa by dynamically changing the concentration of the solution to bring ATPS across the binodal curve. We also demonstrate a density modulation scheme by introducing an ATPS solution mixed with sodium diatrizoate hydrate, which allows to increase the liquid density. By adding precisely metered volumes of water, we spontaneously change the density of the solution on the CMP and show that density marker microbeads fall into the solution according to their corresponding densities. The measured densities of ATPS show a good agreement with densities of microbeads and analytical plots. The results presented in this paper highlight the tremendous potential of CMPs for performing complex on-chip processing of ATPS. We anticipate that this method will be useful in applications such as microparticle-based plasma protein analysis and blood cell fractionation.
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Affiliation(s)
- Byeong-Ui Moon
- Life Sciences Division, National Research Council of Canada, 75 de Mortagne Boulevard, Boucherville, QC J4B 6Y4, Canada
| | - Liviu Clime
- Life Sciences Division, National Research Council of Canada, 75 de Mortagne Boulevard, Boucherville, QC J4B 6Y4, Canada
| | | | - Daniel Brassard
- Life Sciences Division, National Research Council of Canada, 75 de Mortagne Boulevard, Boucherville, QC J4B 6Y4, Canada
| | - Christina Nassif
- Life Sciences Division, National Research Council of Canada, 75 de Mortagne Boulevard, Boucherville, QC J4B 6Y4, Canada
| | - Lidija Malic
- Life Sciences Division, National Research Council of Canada, 75 de Mortagne Boulevard, Boucherville, QC J4B 6Y4, Canada
| | - Teodor Veres
- Life Sciences Division, National Research Council of Canada, 75 de Mortagne Boulevard, Boucherville, QC J4B 6Y4, Canada
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2
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Ahmed T, Yamanishi C, Kojima T, Takayama S. Aqueous Two-Phase Systems and Microfluidics for Microscale Assays and Analytical Measurements. ANNUAL REVIEW OF ANALYTICAL CHEMISTRY (PALO ALTO, CALIF.) 2021; 14:231-255. [PMID: 33950741 DOI: 10.1146/annurev-anchem-091520-101759] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Phase separation is a common occurrence in nature. Synthetic and natural polymers, salts, ionic liquids, surfactants, and biomacromolecules phase separate in water, resulting in an aqueous two-phase system (ATPS). This review discusses the properties, handling, and uses of ATPSs. These systems have been used for protein, nucleic acid, virus, and cell purification and have in recent years found new uses for small organics, polysaccharides, extracellular vesicles, and biopharmaceuticals. Analytical biochemistry applications such as quantifying protein-protein binding, probing for conformational changes, or monitoring enzyme activity have been performed with ATPSs. Not only are ATPSs biocompatible, they also retain their properties at the microscale, enabling miniaturization experiments such as droplet microfluidics, bacterial quorum sensing, multiplexed and point-of-care immunoassays, and cell patterning. ATPSs include coacervates and may find wider interest in the context of intracellular phase separation and origin of life. Recent advances in fundamental understanding and in commercial application are also considered.
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Affiliation(s)
- Tasdiq Ahmed
- Walter H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory School of Medicine, Atlanta, Georgia 30332, USA;
| | - Cameron Yamanishi
- Walter H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory School of Medicine, Atlanta, Georgia 30332, USA;
| | - Taisuke Kojima
- Walter H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory School of Medicine, Atlanta, Georgia 30332, USA;
| | - Shuichi Takayama
- Walter H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory School of Medicine, Atlanta, Georgia 30332, USA;
- Parker H. Petit Institute of Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, Georgia 30332, USA
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3
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Tongdee M, Yamanishi C, Maeda M, Kojima T, Dishinger J, Chantiwas R, Takayama S. One-incubation one-hour multiplex ELISA enabled by aqueous two-phase systems. Analyst 2021; 145:3517-3527. [PMID: 32248215 DOI: 10.1039/d0an00383b] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
This work describes a convenient one-hour enzyme-linked immunosorbent assay (ELISA) formulated with conventional antibodies and horseradish peroxidase (HRP) reagents. The method utilizes aqueous two-phase system (ATPS) droplet formation based on poly(ethylene glycol) (PEG)-containing sample solution-triggered rehydration of dehydrated dextran (DEX) spots that contain all antibody reagents. Key advances in this paper include development of a formulation that allows a quick 1-hour overall incubation time and a procedure where inclusion of the HRP reagent in the PEG solution reduces the number of washing and incubation steps required to perform this assay. As an assay application, a 5-plex cytokine test compares cytokine secretion of differentially-treated human ThP-1 macrophages. Given the use of only readily available reagents and a common Western blot imaging system for the readout, this method is envisioned to be broadly applicable to a variety of multiplex immunoassays. To facilitate broader use, companion image processing software as an ImageJ plugin is also described and provided.
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Affiliation(s)
- Mintra Tongdee
- Department of Chemistry and Center of Excellence for Innovation in Chemistry and Flow Innovation-Research for Science and Technology Laboratories (FIRST Labs), Faculty of Science, Mahidol University, Rama VI Rd., Bangkok 10400, Thailand and Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta 30332, Georgia, USA
| | - Cameron Yamanishi
- Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta 30332, Georgia, USA
| | - Midori Maeda
- Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta 30332, Georgia, USA
| | - Taisuke Kojima
- Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta 30332, Georgia, USA
| | | | - Rattikan Chantiwas
- Department of Chemistry and Center of Excellence for Innovation in Chemistry and Flow Innovation-Research for Science and Technology Laboratories (FIRST Labs), Faculty of Science, Mahidol University, Rama VI Rd., Bangkok 10400, Thailand
| | - Shuichi Takayama
- Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta 30332, Georgia, USA
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4
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Moon BU, Malic L, Morton K, Jeyhani M, Elmanzalawy A, Tsai SSH, Veres T. Evaporation-Driven Water-in-Water Droplet Formation. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2020; 36:14333-14341. [PMID: 33179927 DOI: 10.1021/acs.langmuir.0c02683] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
We present new observations of aqueous two-phase system (ATPS) thermodynamic and interfacial phenomena that occur inside sessile droplets due to water evaporation. Sessile droplets that contain polymeric solutions, which are initially in equilibrium in a single phase, are observed at their three-phase liquid-solid-air contact line. As evaporation of a sessile droplet proceeds, we find that submicron secondary water-in-water (W/W) droplets emerge spontaneously at the edges of the mother sessile droplet due to the resulting phase separation from water evaporation. To understand this phenomenon, we first study the secondary W/W droplet formation process on different substrate materials, namely, glass, polycarbonate (PC), thermoplastic elastomer (TPE), poly(dimethylsiloxane)-coated glass slide (PDMS substrate), and Teflon-coated glass slide (Teflon substrate), and show that secondary W/W droplet formation arises only in lower-contact-angle substrates near the three-phase contact line. Next, we characterize the size of the emergent secondary W/W droplets as a function of time. We observe that W/W drops are formed, coalesced, aligned, and trapped along the contact line of the mother droplet. We demonstrate that this W/W multiple emulsion system can be used to encapsulate magnetic particles and blood cells, and achieve size-based separation. Finally, we show the applicability of this system for protein sensing. This is the first experimental observation of evaporation-induced secondary W/W droplet generation in a sessile droplet. We anticipate that the phenomena described here may be applicable to some biological assay applications, for example, biomarker detection, protein sensing, and point-of-care diagnostic testing.
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Affiliation(s)
- Byeong-Ui Moon
- Life Sciences Division, National Research Council of Canada, Boucherville, Quebec J4B 6Y4, Canada
| | - Lidija Malic
- Life Sciences Division, National Research Council of Canada, Boucherville, Quebec J4B 6Y4, Canada
| | - Keith Morton
- Life Sciences Division, National Research Council of Canada, Boucherville, Quebec J4B 6Y4, Canada
| | - Morteza Jeyhani
- Department of Mechanical and Industrial Engineering, Ryerson University, Toronto M5B 2K3, Canada
- Keenan Research Centre for Biomedical Science, St. Michael's Hospital, Toronto M5B 2K3, Canada
- Institute for Biomedical Engineering, Science and Technology (iBEST), a partnership between Ryerson University and St. Michael's Hospital, Toronto M5B 1W8, Canada
| | - Abdelrahman Elmanzalawy
- Life Sciences Division, National Research Council of Canada, Boucherville, Quebec J4B 6Y4, Canada
| | - Scott S H Tsai
- Department of Mechanical and Industrial Engineering, Ryerson University, Toronto M5B 2K3, Canada
- Keenan Research Centre for Biomedical Science, St. Michael's Hospital, Toronto M5B 2K3, Canada
- Institute for Biomedical Engineering, Science and Technology (iBEST), a partnership between Ryerson University and St. Michael's Hospital, Toronto M5B 1W8, Canada
| | - Teodor Veres
- Life Sciences Division, National Research Council of Canada, Boucherville, Quebec J4B 6Y4, Canada
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Yamanishi C, Oliver CR, Kojima T, Takayama S. Stigmatic Microscopy Enables Low-Cost, 3D, Microscale Particle Imaging Velocimetry in Rehydrating Aqueous Two-Phase Systems. Front Chem 2019; 7:311. [PMID: 31179265 PMCID: PMC6538919 DOI: 10.3389/fchem.2019.00311] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2018] [Accepted: 04/18/2019] [Indexed: 11/13/2022] Open
Abstract
This paper describes the construction of a novel stigmatic microscope and image analysis algorithm to simultaneously analyze convective mixing both inside and outside of rehydrating μL-scale aqueous two-phase system (ATPS) droplets. Stigmatic microscopy is inexpensive and advantageous because it modifies the point-spread function of fluorescent particles to enable measurement of their 3D positions from single 2D images, without needing to take slices. In one application of the technique, the convection patterns captured clarify how different ATPS formulations succeed or fail to exclude cells for patterning. Particle flow traces reveal speed and directionality of circulation, indicating temporary eddies at the outer edge of the rehydrating droplet. In another application, the speed of circulation during rehydration was analyzed for different ATPS formulations and the results used to develop a new fast ELISA procedure. While this paper focuses on ATPS rehydration, the microscope and algorithm should be applicable to a broad range of microfluidic flows where microscale 3D convection is important.
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Affiliation(s)
- Cameron Yamanishi
- The Wallace H Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory School of Medicine, Atlanta, GA, United States
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI, United States
| | - C. Ryan Oliver
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI, United States
- Department of Internal Medicine, University of Michigan, Ann Arbor, MI, United States
| | - Taisuke Kojima
- The Wallace H Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory School of Medicine, Atlanta, GA, United States
| | - Shuichi Takayama
- The Wallace H Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory School of Medicine, Atlanta, GA, United States
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI, United States
- The Parker H Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, GA, United States
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6
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Kojima T, Lin CC, Takayama S, Fan SK. Determination of Aqueous Two-Phase System Binodals and Tie-Lines by Electrowetting-on-Dielectric Droplet Manipulation. Chembiochem 2019; 20:270-275. [PMID: 30394637 PMCID: PMC6452887 DOI: 10.1002/cbic.201800553] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2018] [Indexed: 01/12/2023]
Abstract
Handling the aqueous two-phase systems (ATPSs) formed by liquid-liquid phase separation (LLPS) relies on the accurate construction of binodal curves and tie-lines, which delineate the polymer concentrations required for phase separation and depict the properties of the resulting phases, respectively. Various techniques to determine the binodal curves and tie-lines of ATPSs exist, but most rely on manually pipetting relatively large volumes of fluids in a slow and tedious manner. We describe a method to determine ATPS binodals and tie-lines that overcomes these disadvantages: microscale droplet manipulation by electrowetting-on-dielectric (EWOD). EWOD enables automated handling of droplets in an optically transparent platform that allows for in situ droplet observation. Separated phases are clearly visible, and the volumes of each phase are readily determined. Additionally, in considering the molecular crowding present in living cells, this work examines the role of a macromolecule in prompting LLPS. These results show that EWOD-driven droplet manipulation effectively interrogates the phase dynamics of ATPSs and macromolecular crowding in LLPS.
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Affiliation(s)
- Taisuke Kojima
- The Wallace H Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory School of Medicine, 950 Atlantic Drive NW, Atalanta 30332 (USA)
| | - Chu-Chi Lin
- Department of Mechanical Engineering, National Taiwan University, No.1, Sec. 4, Roosevelt Rd., Taipei 10617 (Taiwan)
| | - Shuichi Takayama
- The Wallace H Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory School of Medicine, 950 Atlantic Drive NW, Atalanta 30332 (USA)
| | - Shih-Kang Fan
- Department of Mechanical Engineering, National Taiwan University, No.1, Sec. 4, Roosevelt Rd., Taipei 10617 (Taiwan)
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7
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van Kooten XF, Bercovici M, Kaigala GV. Extraction of electrokinetically separated analytes with on-demand encapsulation. LAB ON A CHIP 2018; 18:3588-3597. [PMID: 30358796 DOI: 10.1039/c8lc00912k] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Microchip electrokinetic methods are capable of increasing the sensitivity of molecular assays by enriching and purifying target analytes. However, their use is currently limited to assays that can be performed under a high external electric field, as spatial separation and focusing is lost when the electric field is removed. We present a novel method that uses two-phase encapsulation to overcome this limitation. The method uses passive filling and pinning of an oil phase in hydrophobic channels to encapsulate electrokinetically separated and focused analytes with a brief pressure pulse. The resulting encapsulated sample droplet maintains its concentration over long periods of time without requiring an electric field and can be manipulated for further analysis, either on- or off-chip. We demonstrate the method by encapsulating DNA oligonucleotides in a 240 pL aqueous segment after isotachophoresis (ITP) focusing, and show that the concentration remains at 60% of the initial value for tens of minutes, a 22-fold increase over free diffusion after 20 minutes. Furthermore, we demonstrate manipulation of a single droplet by selectively encapsulating amplicon after ITP purification from a polymerase chain reaction (PCR) mix, and performing parallel off-chip detection reactions using the droplet. We provide geometrical design guidelines for devices implementing the encapsulation method, and show how the method can be scaled to multiple analyte zones.
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Affiliation(s)
- Xander F van Kooten
- IBM Research - Zurich, Rüschlikon, Switzerland. and Technion - Israel Institute of Technology, Haifa, Israel.
| | - Moran Bercovici
- Technion - Israel Institute of Technology, Haifa, Israel. and The University of Texas at Austin, Austin, Texas, USA
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8
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Kojima T, Takayama S. Membraneless Compartmentalization Facilitates Enzymatic Cascade Reactions and Reduces Substrate Inhibition. ACS APPLIED MATERIALS & INTERFACES 2018; 10:32782-32791. [PMID: 30179001 PMCID: PMC6258206 DOI: 10.1021/acsami.8b07573] [Citation(s) in RCA: 66] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Living cells possess membraneless organelles formed by liquid-liquid phase separation. With the aim of better understanding the general functions of membraneless microcompartments, this paper constructs acellular multicompartment reaction systems using an aqueous multiphase system. Membraneless coacervate droplets are placed within a molecularly crowded environment, where a larger dextran (DEX) droplet is submerged in a polyethylene glycol (PEG) solution. The coacervate droplets are capable of sequestering reagents and enzymes with a long retention time, and demonstrate multistep cascading reactions through the liquid-liquid interfaces. The ability to change phase dynamics is also demonstrated through salt-mediated dissolution of coacervate droplets, which leads to the release and mixing of separately sequestered reagents and enzymes. Finally, as phase-separated materials in membraneless organelles are often substrates and substrate analogues for the enzymes sequestered or excluded in the organelles, this paper explores the interaction between DEX and dextranase, an enzyme that hydrolyzes DEX. The results reveal that dextranase suffers from substrate inhibition when partitioned directly in a DEX phase but that this inhibition can be mitigated and reactions greatly accelerated by compartmentalization of dextranase inside a coacervate droplet that is adjacent to, but phase-separated from, the DEX phase. The insight that compartmentalization of enzymes can accelerate reactions by mitigating substrate inhibition is particularly novel and is an example where artificial membraneless organelle-like systems may provide new insights into physiological cell functions.
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Affiliation(s)
- Taisuke Kojima
- The Wallace H Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory School of Medicine, Atlanta, GA 30332 USA
| | - Shuichi Takayama
- The Wallace H Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory School of Medicine, Atlanta, GA 30332 USA
- The Parker H Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta GA 30332 USA
- To whom correspondence should be addressed: Prof. Shuichi Takayama, EBB Building, 950 Atlantic Drive NW, Georgia Institute of Technology, GA, USA 30332,
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9
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Moore CL, Taylor EM, Ball KK, Bernock LJ, Griffin RJ, Jung S, Shoeib A, Borrelli MJ. Quantitative microinjection using fluorescence calibration of streaming microdroplets on a superhydrophobic surface. Exp Cell Res 2018; 370:426-433. [PMID: 29981341 DOI: 10.1016/j.yexcr.2018.07.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2018] [Revised: 07/02/2018] [Accepted: 07/03/2018] [Indexed: 10/28/2022]
Abstract
A simple and reproducible procedure was developed to measure the volume of liquid microinjected into cells. A calibration curve of droplet fluorescence intensity versus volume was constructed by injecting a fluorescent dextran solution through a 125-150 µm diameter micropipette into an oil-filled culture dish to create a spray of varied-sized droplets. The droplets retained a spherical shape because they were in an oil medium and they settled onto a glass surface coated with a superhydrophobic surface. Fluorescent micrographs of the droplets were obtained and analyzed with Image-J software to quantify the fluorescence intensity and radius of each spherical droplet to produce the calibration curve. Subsequently, Dut-145 human prostate carcinoma cells were microinjected with the same fluorescent dextran solution and fluorescent micrographs of the cells were obtained using the identical exposure conditions used to photograph the droplets. The measured fluorescence intensity of the microinjected cells was entered into the formula for the regression line that was fit to the calibration curve allowing determination of the volume of solution injected into each cell. Thus, a mixture consisting of known concentrations of a test material of test material (macromolecules, drugs, etc.) and a fluorescent dextran, volumetric, tracer can be used to quantify the relationship between the amount of a microinjected material and subsequent effects on cells.
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Affiliation(s)
- Christopher L Moore
- Departments of Radiology, Center for Advanced Surface Engineering, Arkansas Nanomedicine Center, University of Arkansas for Medical Sciences, 4301 West Markham Street, Little Rock, AR 72205, USA.
| | - Erin M Taylor
- Departments of Radiology, Center for Advanced Surface Engineering, Arkansas Nanomedicine Center, University of Arkansas for Medical Sciences, 4301 West Markham Street, Little Rock, AR 72205, USA.
| | - Kelly K Ball
- Departments of Radiology, Center for Advanced Surface Engineering, Arkansas Nanomedicine Center, University of Arkansas for Medical Sciences, 4301 West Markham Street, Little Rock, AR 72205, USA.
| | - Laura J Bernock
- Departments of Radiology, Center for Advanced Surface Engineering, Arkansas Nanomedicine Center, University of Arkansas for Medical Sciences, 4301 West Markham Street, Little Rock, AR 72205, USA.
| | - Robert J Griffin
- Departments of Radiation Oncology, Center for Advanced Surface Engineering, Arkansas Nanomedicine Center, University of Arkansas for Medical Sciences, 4301 West Markham Street, Little Rock, AR 72205, USA.
| | - Seunghyun Jung
- Departments of Radiology, Center for Advanced Surface Engineering, Arkansas Nanomedicine Center, University of Arkansas for Medical Sciences, 4301 West Markham Street, Little Rock, AR 72205, USA.
| | - Amal Shoeib
- Departments of Radiology, Center for Advanced Surface Engineering, Arkansas Nanomedicine Center, University of Arkansas for Medical Sciences, 4301 West Markham Street, Little Rock, AR 72205, USA.
| | - Michael J Borrelli
- Departments of Radiology, Center for Advanced Surface Engineering, Arkansas Nanomedicine Center, University of Arkansas for Medical Sciences, 4301 West Markham Street, Little Rock, AR 72205, USA.
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Chao Y, Mak SY, Rahman S, Zhu S, Shum HC. Generation of High-Order All-Aqueous Emulsion Drops by Osmosis-Driven Phase Separation. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2018; 14:e1802107. [PMID: 30118584 DOI: 10.1002/smll.201802107] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/02/2018] [Revised: 07/28/2018] [Indexed: 05/14/2023]
Abstract
Droplets containing ternary mixtures can spontaneously phase-separate into high-order structures upon a change in composition, which provides an alternative strategy to form multiphase droplets. However, existing strategies always involve nonaqueous solvents that limit the potential applications of the resulting multiple droplets, such as encapsulation of biomolecules. Here, a robust approach to achieve high-order emulsion drops with an all-aqueous nature from two aqueous phases by osmosis-induced phase separation on a microfluidic platform is presented. This technique is enabled by the existence of an interface of the two aqueous phases and phase separation caused by an osmolality difference between the two phases. The complexity of emulsion drops induced by phase separation could be controlled by varying the initial concentration of solutes and is systematically illustrated in a state diagram. In particular, this technique is utilized to successfully achieve high-order all-aqueous droplets in a different aqueous two-phase system. The proposed method is simple since it only requires two initial aqueous solutions for generating multilayered, organic-solvent-free all-aqueous emulsion drops, and thus these multiphase emulsion drops can be further tailored to serve as highly biocompatible material templates.
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Affiliation(s)
- Youchuang Chao
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong, China
- HKU-Shenzhen Institute of Research and Innovation (HKU-SIRI), Shenzhen, Guangdong, 518000, China
| | - Sze Yi Mak
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong, China
- HKU-Shenzhen Institute of Research and Innovation (HKU-SIRI), Shenzhen, Guangdong, 518000, China
| | - Shakurur Rahman
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong, China
| | - Shipei Zhu
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong, China
| | - Ho Cheung Shum
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong, China
- HKU-Shenzhen Institute of Research and Innovation (HKU-SIRI), Shenzhen, Guangdong, 518000, China
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11
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Ruthven M, Ko KR, Agarwal R, Frampton JP. Microscopic evaluation of aqueous two-phase system emulsion characteristics enables rapid determination of critical polymer concentrations for solution micropatterning. Analyst 2018; 142:1938-1945. [PMID: 28487922 DOI: 10.1039/c7an00255f] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Aqueous two-phase systems have emerged as valuable tools for microscale analysis of cell growth and many other biotechnology applications. The most critical step in developing an aqueous two-phase system for a specific application is identifying the critical concentrations at which the polymer solutions phase-separate. Current techniques for determining these critical concentrations rely on laborious methods, highly specialized assays or computational methods that make this step difficult for non-specialists. To overcome these limitations, we present a simplified assay that uses only readily accessible laboratory instruments and consumables (e.g., multichannel micropipettes, 96-well plates and a simple compound microscope) to determine the critical concentrations of aqueous two-phase system-forming polymers. We demonstrate that formulations selected from phase diagrams that describe these critical concentrations can be applied for solution micropatterning of cells.
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12
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13
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Bleier BJ, Anna SL, Walker LM. Microfluidic Droplet-Based Tool To Determine Phase Behavior of a Fluid System with High Composition Resolution. J Phys Chem B 2018; 122:4067-4076. [DOI: 10.1021/acs.jpcb.8b01013] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Affiliation(s)
- Blake J. Bleier
- Department of Chemical Engineering, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, United States
| | - Shelley L. Anna
- Department of Chemical Engineering, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, United States
| | - Lynn M. Walker
- Department of Chemical Engineering, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, United States
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14
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Teixeira AG, Agarwal R, Ko KR, Grant‐Burt J, Leung BM, Frampton JP. Emerging Biotechnology Applications of Aqueous Two-Phase Systems. Adv Healthc Mater 2018; 7:e1701036. [PMID: 29280350 DOI: 10.1002/adhm.201701036] [Citation(s) in RCA: 54] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2017] [Revised: 10/30/2017] [Indexed: 02/06/2023]
Abstract
Liquid-liquid phase separation between aqueous solutions containing two incompatible polymers, a polymer and a salt, or a polymer and a surfactant, has been exploited for a wide variety of biotechnology applications throughout the years. While many applications for aqueous two-phase systems fall within the realm of separation science, the ability to partition many different materials within these systems, coupled with recent advances in materials science and liquid handling, has allowed bioengineers to imagine new applications. This progress report provides an overview of the history and key properties of aqueous two-phase systems to lend context to how these materials have progressed to modern applications such as cellular micropatterning and bioprinting, high-throughput 3D tissue assembly, microscale biomolecular assay development, facilitation of cell separation and microcapsule production using microfluidic devices, and synthetic biology. Future directions and present limitations and design considerations of this adaptable and promising toolkit for biomolecule and cellular manipulation are further evaluated.
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Affiliation(s)
- Alyne G. Teixeira
- School of Biomedical Engineering Dalhousie University 5981 University Avenue Halifax NS B3H 4R2 Canada
| | - Rishima Agarwal
- School of Biomedical Engineering Dalhousie University 5981 University Avenue Halifax NS B3H 4R2 Canada
| | - Kristin Robin Ko
- School of Biomedical Engineering Dalhousie University 5981 University Avenue Halifax NS B3H 4R2 Canada
| | - Jessica Grant‐Burt
- School of Biomedical Engineering Dalhousie University 5981 University Avenue Halifax NS B3H 4R2 Canada
| | - Brendan M. Leung
- School of Biomedical Engineering Dalhousie University 5981 University Avenue Halifax NS B3H 4R2 Canada
- Department of Applied Oral Science Dalhousie University 5981 University Avenue Halifax NS B3H 4R2 Canada
| | - John P. Frampton
- School of Biomedical Engineering Dalhousie University 5981 University Avenue Halifax NS B3H 4R2 Canada
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15
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Kojima T, Hirai K, Zhou Y, Weerappuli P, Takayama S, Kotov NA. Nanoparticle Assemblies into Luminescent Dendrites in Shrinking Microdroplets. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2016; 32:12468-12475. [PMID: 27571169 DOI: 10.1021/acs.langmuir.6b01960] [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
The self-assembly of nanoparticles (NPs) is essential for emerging dispersion-based energy-conscious technologies. Of particular interest are micro- and macro-scale self-organizing superstructures that can bridge 2D/3D processing scales. Here we report the spontaneous assembly of CdTe NPs within an aqueous microdroplet suspended in soybean oil. The gradual diffusion of the water into the surrounding medium results in shrinking of the microdroplet, and a concomitant formation of branched assemblies from CdTe NPs that evolve in size from ∼50 μm to ∼1000 μm. The fractal dimension of NP assemblies increases from ∼1.7 to ∼1.9 during the assembly process. We found that constituents of the soybean oil enter the aqueous solution across the microdroplet interface and affect NP assembly. The obtained NP dendrites can be further altered morphologically by illumination with light that results in the disassembly of the NP dendrites. The use of this microheterogeneous dispersion platform with partially soluble hydrophilic and hydrophobic solvents highlights the sensitivity of the NP assembly process to environment and presents an opportunity to explore droplet-confined NP assembly.
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Affiliation(s)
| | | | | | - Priyan Weerappuli
- Department of Biomedical Engineering, Wayne State University , Detroit, Michigan 48202, United States
| | - Shuichi Takayama
- Michigan Center for Integrative Research in Critical Care , Ann Arbor, Michigan 48109, United States
| | - Nicholas A Kotov
- Michigan Center for Integrative Research in Critical Care , Ann Arbor, Michigan 48109, United States
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16
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Eiden L, Yamanishi C, Takayama S, Dishinger JF. Aqueous Two-Phase System Rehydration of Antibody–Polymer Microarrays Enables Convenient Compartmentalized Multiplex Immunoassays. Anal Chem 2016; 88:11328-11334. [DOI: 10.1021/acs.analchem.6b02960] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Affiliation(s)
- Lisa Eiden
- PHASIQ, Inc., Ann Arbor, Michigan 48109, United States
| | - Cameron Yamanishi
- Department
of Biomedical Engineering, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Shuichi Takayama
- Department
of Biomedical Engineering, University of Michigan, Ann Arbor, Michigan 48109, United States
- Department
of Macromolecular Science and Engineering, University of Michigan, Ann Arbor, Michigan 48109, United States
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17
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Vázquez-Villegas P, Ouellet E, González C, Ruiz-Ruiz F, Rito-Palomares M, Haynes CA, Aguilar O. A microdevice assisted approach for the preparation, characterization and selection of continuous aqueous two-phase systems: from micro to bench-scale. LAB ON A CHIP 2016; 16:2662-2672. [PMID: 27302418 DOI: 10.1039/c6lc00333h] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Aqueous two-phase systems (ATPS) have emerged as an alternative strategy for the recovery and purification of a wide variety of biological products. Typical process development requires a large screening of experimental conditions towards industrial adoption where continuous processes are preferred. In this work, it was proved that under certain flow conditions, ATPS could be formed continuously inside a microchannel, starting from stocks of phase components. Staggered herringbone chaotic micromixers included within the device sequentially and rapidly prepare two-phase systems across an entire range of useful phase compositions. Two-phase diagrams (binodal curves) were easily plotted using the cloud-point method for systems of different components and compared with previously reported curves for each system, proving that phase formation inside the device correlated with the previously reported diagrams. A proof of concept for sample partitioning in such a microdevice was performed with two different experimental models: BSA and red blood cells. Finally, the microdevice was employed to obtain information about the recovery and partition coefficient of invertase from a real complex mixture of proteins (yeast extract) to design a process for the recovery of the enzyme selecting a suitable system and composition to perform the process at bench-scale.
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Affiliation(s)
- Patricia Vázquez-Villegas
- Escuela de Ingeniería y Ciencias, Tecnologico de Monterrey, Ave. Eugenio Garza Sada 2501, Monterrey, N.L. 64849, Mexico.
| | - Eric Ouellet
- Michael Smith Laboratories, University of British Columbia, Vancouver, BC, V6T 1Z4 Canada
| | - Claudia González
- Escuela de Ingeniería y Ciencias, Tecnologico de Monterrey, Ave. Eugenio Garza Sada 2501, Monterrey, N.L. 64849, Mexico.
| | - Federico Ruiz-Ruiz
- Escuela de Ingeniería y Ciencias, Tecnologico de Monterrey, Ave. Eugenio Garza Sada 2501, Monterrey, N.L. 64849, Mexico.
| | - Marco Rito-Palomares
- Escuela de Ingeniería y Ciencias, Tecnologico de Monterrey, Ave. Eugenio Garza Sada 2501, Monterrey, N.L. 64849, Mexico.
| | - Charles A Haynes
- Michael Smith Laboratories, University of British Columbia, Vancouver, BC, V6T 1Z4 Canada
| | - Oscar Aguilar
- Escuela de Ingeniería y Ciencias, Tecnologico de Monterrey, Ave. Eugenio Garza Sada 2501, Monterrey, N.L. 64849, Mexico.
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18
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Moon BU, Hwang DK, Tsai SSH. Shrinking, growing, and bursting: microfluidic equilibrium control of water-in-water droplets. LAB ON A CHIP 2016; 16:2601-2608. [PMID: 27314278 DOI: 10.1039/c6lc00576d] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
We demonstrate the dynamic control of aqueous two phase system (ATPS) droplets in shrinking, growing, and dissolving conditions. The ATPS droplets are formed passively in a flow focusing microfluidic channel, where the dextran-rich (DEX) and polyethylene glycol-rich (PEG) solutions are introduced as disperse and continuous phases, respectively. To vary the ATPS equilibrium condition, we infuse into a secondary inlet the PEG phase from a different polymer concentration ATPS. We find that the resulting alteration of the continuous PEG phase can cause droplets to shrink or grow by approximately 45 and 30%, respectively. This volume change is due to water exchange between the disperse DEX and continuous PEG phases, as the system tends towards new equilibria. We also develop a simple model, based on the ATPS binodal curve and tie lines, that predicts the amount of droplet shrinkage or growth, based on the change in the continuous phase PEG concentration. We observe a good agreement between our experimental results and the model. Additionally, we find that when the continuous phase PEG concentration is reduced such that PEG and DEX phases no longer phase separate, the ATPS droplets are dissolved into the continuous phase. We apply this method to controllably release encapsulated microparticles and cells, and we find that their release occurs within 10 seconds. Our approach uses the dynamic equilibrium of ATPS to control droplet size along the microfluidic channel. By modulating the ATPS equilibrium, we are able to shrink, grow, and dissolve ATPS droplets in situ. We anticipate that this approach may find utility in many biomedical settings, for example, in drug and cell delivery and release applications.
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Affiliation(s)
- Byeong-Ui Moon
- Department of Mechanical and Industrial Engineering, Ryerson University, Toronto, Canada. and Keenan Research Centre for Biomedical Science, St. Michael's Hospital, Toronto, Canada and Institute for Biomedical Engineering, Science and Technology (iBEST), A partnership between Ryerson University and St. Michael's Hospital, Toronto, Canada
| | - Dae Kun Hwang
- Department of Mechanical and Industrial Engineering, Ryerson University, Toronto, Canada. and Keenan Research Centre for Biomedical Science, St. Michael's Hospital, Toronto, Canada and Department of Chemical Engineering, Ryerson University, Toronto, Canada
| | - Scott S H Tsai
- Department of Mechanical and Industrial Engineering, Ryerson University, Toronto, Canada. and Keenan Research Centre for Biomedical Science, St. Michael's Hospital, Toronto, Canada and Institute for Biomedical Engineering, Science and Technology (iBEST), A partnership between Ryerson University and St. Michael's Hospital, Toronto, Canada
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19
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Aqueous Two Phase System Assisted Self-Assembled PLGA Microparticles. Sci Rep 2016; 6:27736. [PMID: 27279329 PMCID: PMC4899744 DOI: 10.1038/srep27736] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2016] [Accepted: 05/20/2016] [Indexed: 11/18/2022] Open
Abstract
Here, we produce poly(lactide-co-glycolide) (PLGA) based microparticles with varying morphologies, and temperature responsive properties utilizing a Pluronic F127/dextran aqueous two-phase system (ATPS) assisted self-assembly. The PLGA polymer, when emulsified in Pluronic F127/dextran ATPS, forms unique microparticle structures due to ATPS guided-self assembly. Depending on the PLGA concentration, the particles either formed a core-shell or a composite microparticle structure. The microparticles facilitate the simultaneous incorporation of both hydrophobic and hydrophilic molecules, due to their amphiphilic macromolecule composition. Further, due to the lower critical solution temperature (LCST) properties of Pluronic F127, the particles exhibit temperature responsiveness. The ATPS based microparticle formation demonstrated in this study, serves as a novel platform for PLGA/polymer based tunable micro/nano particle and polymersome development. The unique properties may be useful in applications such as theranostics, synthesis of complex structure particles, bioreaction/mineralization at the two-phase interface, and bioseparations.
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20
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Soares RRG, Azevedo AM, Van Alstine JM, Aires-Barros MR. Partitioning in aqueous two-phase systems: Analysis of strengths, weaknesses, opportunities and threats. Biotechnol J 2015. [PMID: 26213222 DOI: 10.1002/biot.201400532] [Citation(s) in RCA: 72] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
For half a century aqueous two-phase systems (ATPSs) have been applied for the extraction and purification of biomolecules. In spite of their simplicity, selectivity, and relatively low cost they have not been significantly employed for industrial scale bioprocessing. Recently their ability to be readily scaled and interface easily in single-use, flexible biomanufacturing has led to industrial re-evaluation of ATPSs. The purpose of this review is to perform a SWOT analysis that includes a discussion of: (i) strengths of ATPS partitioning as an effective and simple platform for biomolecule purification; (ii) weaknesses of ATPS partitioning in regard to intrinsic problems and possible solutions; (iii) opportunities related to biotechnological challenges that ATPS partitioning may solve; and (iv) threats related to alternative techniques that may compete with ATPS in performance, economic benefits, scale up and reliability. This approach provides insight into the current status of ATPS as a bioprocessing technique and it can be concluded that most of the perceived weakness towards industrial implementation have now been largely overcome, thus paving the way for opportunities in fermentation feed clarification, integration in multi-stage operations and in single-step purification processes.
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Affiliation(s)
- Ruben R G Soares
- IBB - Institute for Bioengineering and Biosciences, Department of Bioengineering, Instituto Superior Técnico, Universidade de Lisboa, Lisbon, Portugal
| | - Ana M Azevedo
- IBB - Institute for Bioengineering and Biosciences, Department of Bioengineering, Instituto Superior Técnico, Universidade de Lisboa, Lisbon, Portugal
| | - James M Van Alstine
- Division of Industrial Biotechnology, School of Biotechnology, Royal Institute of Technology, Stockholm, Sweden.,JMVA Biotech, Stockholm, Sweden
| | - M Raquel Aires-Barros
- IBB - Institute for Bioengineering and Biosciences, Department of Bioengineering, Instituto Superior Técnico, Universidade de Lisboa, Lisbon, Portugal.
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21
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Breisig H, Wessling M. Droplet formation and shrinking in aqueous two-phase systems using a membrane emulsification method. BIOMICROFLUIDICS 2015; 9:044122. [PMID: 26339321 PMCID: PMC4552692 DOI: 10.1063/1.4929519] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/03/2015] [Accepted: 08/12/2015] [Indexed: 06/05/2023]
Abstract
Using a membrane emulsification method based on porous hollow-fiber membranes in combination with an aqueous two-phase system (ATPS), we are able to produce "water-in-water" droplets with narrow-dispersed size distributions. The equilibrium phases of the aqueous two-phase system polyethylene glycol-dipotassium hydrogen phosphate are used for this purpose. The droplet diameter of a given fluid system is determined by the flow rates of the continuous and disperse phase as well as the hollow fiber dimensions. When diluting the disperse phase and thus moving the ATPS system out of equilibrium, the droplet size can be further reduced in comparison to the equilibrium case. Generally, droplets formed with this method have diameters 20%-60% larger than the inner hollow fiber diameter. The new strategy of diluting the disperse phase allows the production of droplet diameter below the inner diameter of the membrane.
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22
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Tsumoto K, Arai M, Nakatani N, Watanabe SN, Yoshikawa K. Does DNA exert an active role in generating cell-sized spheres in an aqueous solution with a crowding binary polymer? Life (Basel) 2015; 5:459-66. [PMID: 25809964 PMCID: PMC4390863 DOI: 10.3390/life5010459] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2014] [Accepted: 02/02/2015] [Indexed: 11/18/2022] Open
Abstract
We report the spontaneous generation of a cell-like morphology in an environment crowded with the polymers dextran and polyethylene glycol (PEG) in the presence of DNA. DNA molecules were selectively located in the interior of dextran-rich micro-droplets, when the composition of an aqueous two-phase system (ATPS) was near the critical condition of phase-segregation. The resulting micro-droplets could be controlled by the use of optical tweezers. As an example of laser manipulation, the dynamic fusion of two droplets is reported, which resembles the process of cell division in time-reverse. A hypothetical scenario for the emergence of a primitive cell with DNA is briefly discussed.
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Affiliation(s)
- Kanta Tsumoto
- Graduate School of Engineering, Mie University, Mie, 514-8507, Japan.
| | - Masafumi Arai
- Faculty of Life and Medical Sciences, Doshisha University, Kyotanabe, 610-0394, Japan.
| | - Naoki Nakatani
- Faculty of Life and Medical Sciences, Doshisha University, Kyotanabe, 610-0394, Japan.
| | - Shun N Watanabe
- Faculty of Life and Medical Sciences, Doshisha University, Kyotanabe, 610-0394, Japan.
| | - Kenichi Yoshikawa
- Faculty of Life and Medical Sciences, Doshisha University, Kyotanabe, 610-0394, Japan.
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23
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Eslami F, Elliott JAW. Role of Precipitating Solute Curvature on Microdrops and Nanodrops during Concentrating Processes: The Nonideal Ostwald–Freundlich Equation. J Phys Chem B 2014; 118:14675-86. [DOI: 10.1021/jp5063786] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Fatemeh Eslami
- Department of Chemical and
Materials Engineering, University of Alberta, Edmonton AB, Canada T6G 2V4
| | - Janet A. W. Elliott
- Department of Chemical and
Materials Engineering, University of Alberta, Edmonton AB, Canada T6G 2V4
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24
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Eslami F, Elliott JAW. Stability Analysis of Microdrops during Concentrating Processes. J Phys Chem B 2014; 118:3630-41. [DOI: 10.1021/jp4072229] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Fatemeh Eslami
- Department of Chemical and
Materials Engineering, University of Alberta, Edmonton, Alberta, Canada T6G 2V4
| | - Janet A. W. Elliott
- Department of Chemical and
Materials Engineering, University of Alberta, Edmonton, Alberta, Canada T6G 2V4
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