1
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Sharma V, Mottafegh A, Joo JU, Kang JH, Wang L, Kim DP. Toward microfluidic continuous-flow and intelligent downstream processing of biopharmaceuticals. LAB ON A CHIP 2024; 24:2861-2882. [PMID: 38751338 DOI: 10.1039/d3lc01097j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2024]
Abstract
Biopharmaceuticals have emerged as powerful therapeutic agents, revolutionizing the treatment landscape for various diseases, including cancer, infectious diseases, autoimmune and genetic disorders. These biotherapeutics pave the way for precision medicine with their unique and targeted capabilities. The production of high-quality biologics entails intricate manufacturing processes, including cell culture, fermentation, purification, and formulation, necessitating specialized facilities and expertise. These complex processes are subject to rigorous regulatory oversight to evaluate the safety, efficacy, and quality of biotherapeutics prior to clinical approval. Consequently, these drugs undergo extensive purification unit operations to achieve high purity by effectively removing impurities and contaminants. The field of personalized precision medicine necessitates the development of novel and highly efficient technologies. Microfluidic technology addresses unmet needs by enabling precise and compact separation, allowing rapid, integrated and continuous purification modules. Moreover, the integration of intelligent biomanufacturing systems with miniaturized devices presents an opportunity to significantly enhance the robustness of complex downstream processing of biopharmaceuticals, with the benefits of automation and advanced control. This allows seamless data exchange, real-time monitoring, and synchronization of purification steps, leading to improved process efficiency, data management, and decision-making. Integrating autonomous systems into biopharmaceutical purification ensures adherence to regulatory standards, such as good manufacturing practice (GMP), positioning the industry to effectively address emerging market demands for personalized precision nano-medicines. This perspective review will emphasize on the significance, challenges, and prospects associated with the adoption of continuous, integrated, and intelligent methodologies in small-scale downstream processing for various types of biologics. By utilizing microfluidic technology and intelligent systems, purification processes can be enhanced for increased efficiency, cost-effectiveness, and regulatory compliance, shaping the future of biopharmaceutical production and enabling the development of personalized and targeted therapies.
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Affiliation(s)
- Vikas Sharma
- Center for Intelligent Microprocess of Pharmaceutical Synthesis, Department of Chemical Engineering, Pohang University of Science and Technology (POSTECH), Pohang 37673, Republic of Korea.
| | - Amirreza Mottafegh
- Center for Intelligent Microprocess of Pharmaceutical Synthesis, Department of Chemical Engineering, Pohang University of Science and Technology (POSTECH), Pohang 37673, Republic of Korea.
| | - Jeong-Un Joo
- Center for Intelligent Microprocess of Pharmaceutical Synthesis, Department of Chemical Engineering, Pohang University of Science and Technology (POSTECH), Pohang 37673, Republic of Korea.
| | - Ji-Ho Kang
- Center for Intelligent Microprocess of Pharmaceutical Synthesis, Department of Chemical Engineering, Pohang University of Science and Technology (POSTECH), Pohang 37673, Republic of Korea.
| | - Lei Wang
- School of Chemistry and Chemical Engineering, Harbin Institute of Technology, Harbin 150001, Heilongjiang, P. R. China
| | - Dong-Pyo Kim
- Center for Intelligent Microprocess of Pharmaceutical Synthesis, Department of Chemical Engineering, Pohang University of Science and Technology (POSTECH), Pohang 37673, Republic of Korea.
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2
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Zhang Q, Xie T, Yi X, Xing G, Feng S, Chen S, Li Y, Lin JM. Microfluidic Aqueous Two-Phase Focusing of Chemical Species for In Situ Subcellular Stimulation. ACS APPLIED MATERIALS & INTERFACES 2023; 15:45640-45650. [PMID: 37733946 DOI: 10.1021/acsami.3c09665] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/23/2023]
Abstract
Confinement of chemical species in a controllable micrometer-level (several to a dozen micrometers) space in an aqueous environment is essential for precisely manipulating chemical events in subcellular regions. However, rapid diffusion and hard-to-control micrometer-level fluids make it a tough challenge. Here, a versatile open microfluidic method based on an aqueous two-phase system (ATPS) is developed to restrict species inside an open space with micron-level width. Unequal standard chemical potentials of the chemical species in two phases and space-time correspondence in the microfluidic system prevent outward diffusion across the phase interface, retaining the target species inside its preferred phase flow and creating a sharp boundary with a dramatic concentration change. Then, the chemical flow (the preferred phase with target chemical species) is precisely manipulated by a microfluidic probe, which can be compressed to a micron-level width and aimed at an arbitrary position of the sample. As a demonstration of the feasibility and versatility of the strategy, chemical flow is successfully applied to subcellular regions of various kinds of living single cells. Subcellular regions are successfully labeled (cytomembrane and mitochondria) and damaged. Healing-regeneration behaviors of living single cells are triggered by subcellular damage and analyzed. The method is relatively general regarding the species of chemicals and biosamples, which could promote deeper cell research.
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Affiliation(s)
- Qiang Zhang
- Beijing Key Laboratory of Microanalytical Methods and Instrumentation, Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology (Ministry of Education), Department of Chemistry, Tsinghua University, Beijing 100084, China
| | - Tianze Xie
- Beijing Key Laboratory of Microanalytical Methods and Instrumentation, Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology (Ministry of Education), Department of Chemistry, Tsinghua University, Beijing 100084, China
| | - Xizhen Yi
- Beijing Key Laboratory of Microanalytical Methods and Instrumentation, Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology (Ministry of Education), Department of Chemistry, Tsinghua University, Beijing 100084, China
| | - Gaowa Xing
- Beijing Key Laboratory of Microanalytical Methods and Instrumentation, Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology (Ministry of Education), Department of Chemistry, Tsinghua University, Beijing 100084, China
| | - Shuo Feng
- Beijing Key Laboratory of Microanalytical Methods and Instrumentation, Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology (Ministry of Education), Department of Chemistry, Tsinghua University, Beijing 100084, China
| | - Shulang Chen
- Beijing Key Laboratory of Microanalytical Methods and Instrumentation, Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology (Ministry of Education), Department of Chemistry, Tsinghua University, Beijing 100084, China
| | - Yuxuan Li
- Beijing Key Laboratory of Microanalytical Methods and Instrumentation, Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology (Ministry of Education), Department of Chemistry, Tsinghua University, Beijing 100084, China
| | - Jin-Ming Lin
- Beijing Key Laboratory of Microanalytical Methods and Instrumentation, Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology (Ministry of Education), Department of Chemistry, Tsinghua University, Beijing 100084, China
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3
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Phakoukaki YV, O'Shaughnessy P, Angeli P. Flow patterns of ionic liquid based aqueous biphasic systems in small channels. Chem Eng Sci 2023. [DOI: 10.1016/j.ces.2022.118197] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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4
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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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5
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Pavlovic M, Antonietti M, Schmidt BVKJ, Zeininger L. Responsive Janus and Cerberus emulsions via temperature-induced phase separation in aqueous polymer mixtures. J Colloid Interface Sci 2020; 575:88-95. [PMID: 32361049 DOI: 10.1016/j.jcis.2020.04.067] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2020] [Revised: 04/16/2020] [Accepted: 04/17/2020] [Indexed: 12/14/2022]
Abstract
Complex aqueous emulsions represent a promising material platform for the encapsulation of cells, pharmaceuticals, or nutrients, for the fabrication of structured particles, as well as for mimicking the barrier-free compartmentalization of biomolecules found in living cells. Herein, we report a novel, simple, and scalable method of creating multicomponent aqueous droplets with highly uniform internal droplet morphologies that can be controllably altered after emulsification by making use of a thermal phase separation approach. Specifically, temperature-induced phase separation inside as-formed emulsion droplets comprising aqueous mixtures of two or more hydrophilic polymers allows for the generation of Janus and Cerberus emulsion droplets with adjustable internal morphologies that are solely controlled by a balance of interfacial tensions. We demonstrate our approach by applying both, microfluidic and scalable batch production, and present a detailed model study with predictive capabilities that enables fine-tuning and dynamically altering the droplet morphology as a function of types, molecular weights, and hydrophilicities of the polymers as well as the surfactant hydrophilic-lipophilic balance. The ability to rationally design complex aqueous emulsion droplets with previously unattainable dynamic control over their morphologies after emulsification entails the potential to design new responsive soft materials with implications for a variety of applications beyond encapsulation, including the design of complex adaptive and self-regulating materials, e.g. for chemical and biological sensing applications.
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Affiliation(s)
- Marko Pavlovic
- Department of Colloid Chemistry, Max Planck Institute of Colloids and Interfaces, Am Mühlenberg 1, 14476 Potsdam, Germany
| | - Markus Antonietti
- Department of Colloid Chemistry, Max Planck Institute of Colloids and Interfaces, Am Mühlenberg 1, 14476 Potsdam, Germany
| | | | - Lukas Zeininger
- Department of Colloid Chemistry, Max Planck Institute of Colloids and Interfaces, Am Mühlenberg 1, 14476 Potsdam, Germany.
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6
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Curtis A, Cheng JJ, Hui EE. Cell patterning by surface tension pinning in microfluidic channels. BIOMICROFLUIDICS 2020; 14:024102. [PMID: 32161633 PMCID: PMC7058426 DOI: 10.1063/1.5140990] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/05/2019] [Accepted: 02/14/2020] [Indexed: 05/15/2023]
Abstract
We present a simple method to pattern multiple cell populations inside a microfluidic channel. The microchannel is partially filled with a cell suspension, and the position of the liquid boundary remains pinned by surface tension. Cells then adhere only in the filled portion of the channel, producing a very sharp boundary. The process can be performed in an unmodified microfluidic channel with only a manual syringe and can be repeated multiple times to pattern cocultures or tricultures. We demonstrate the patterning method with two different mammalian cell types, 3T3 fibroblasts and NMuMG epithelial cells, and channel heights of 1.5 mm and 0.5 mm. We anticipate that this method will be useful for studies of cell-cell interactions where precise control of the fluidic microenvironment is required.
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Affiliation(s)
- Allison Curtis
- Department of Biomedical Engineering, University of California, Irvine, California 92697-2715, USA
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7
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Dincau B, Dressaire E, Sauret A. Pulsatile Flow in Microfluidic Systems. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2020; 16:e1904032. [PMID: 31657131 DOI: 10.1002/smll.201904032] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/24/2019] [Revised: 09/17/2019] [Indexed: 06/10/2023]
Abstract
This review describes the current knowledge and applications of pulsatile flow in microfluidic systems. Elements of fluid dynamics at low Reynolds number are first described in the context of pulsatile flow. Then the practical applications in microfluidic processes are presented: the methods to generate a pulsatile flow, the generation of emulsion droplets through harmonic flow rate perturbation, the applications in mixing and particle separation, and the benefits of pulsatile flow for clog mitigation. The second part of the review is devoted to pulsatile flow in biological applications. Pulsatile flows can be used for mimicking physiological systems, to alter or enhance cell cultures, and for bioassay automation. Pulsatile flows offer unique advantages over a steady flow, especially in microfluidic systems, but also require some new physical insights and more rigorous investigation to fully benefit future applications.
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Affiliation(s)
- Brian Dincau
- Department of Mechanical Engineering, University of California, Santa Barbara, Santa Barbara, CA, 93106, USA
| | - Emilie Dressaire
- Department of Mechanical Engineering, University of California, Santa Barbara, Santa Barbara, CA, 93106, USA
| | - Alban Sauret
- Department of Mechanical Engineering, University of California, Santa Barbara, Santa Barbara, CA, 93106, USA
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8
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Chao Y, Shum HC. Emerging aqueous two-phase systems: from fundamentals of interfaces to biomedical applications. Chem Soc Rev 2020; 49:114-142. [DOI: 10.1039/c9cs00466a] [Citation(s) in RCA: 138] [Impact Index Per Article: 34.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
This review summarizes recent advances of aqueous two-phase systems (ATPSs), particularly their interfaces, with a focus on biomedical applications.
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Affiliation(s)
- Youchuang Chao
- Department of Mechanical Engineering
- The University of Hong Kong
- China
| | - Ho Cheung Shum
- Department of Mechanical Engineering
- The University of Hong Kong
- China
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9
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McQueen L, Lai D. Ionic Liquid Aqueous Two-Phase Systems From a Pharmaceutical Perspective. Front Chem 2019; 7:135. [PMID: 30931300 PMCID: PMC6428778 DOI: 10.3389/fchem.2019.00135] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2018] [Accepted: 02/21/2019] [Indexed: 12/30/2022] Open
Abstract
Aqueous Two-Phase Systems (ATPSs) have been extensively studied for their ability to simultaneously separate and purify active pharmaceutical ingredients (APIs) and key intermediates with high yields and high purity. Depending on the ATPS composition, it can be adapted for the separation and purification of cells, nucleic acids, proteins, antibodies, and small molecules. This method has been shown to be scalable, allowing it to be used in the milliliter scale for early drug development to thousands of liters in manufacture for commercial supply. The benefits of ATPS in pharmaceutical separations is increasingly being recognized and investigated by larger pharmaceutical companies. ATPSs use identical instrumentation and similar methodology, therefore a change from traditional methods has a theoretical low barrier of adoption. The cost of typical components used to form an ATPS at large scale, particularly that of polymer-polymer systems, is the primary challenge to widespread use across industry. However, there are a few polymer-salt examples where the increase in yield at commercial scale justifies the cost of using ATPSs for macromolecule purification. More recently, Ionic Liquids (ILs) have been used for ATPS separations that is more sustainable as a solvent, and more economical than polymers often used in ATPSs for small molecule applications. Such IL-ATPSs still retain much of the attractive characteristics such as customizable chemical and physical properties, stability, safety, and most importantly, can provide higher yield separations of organic compounds, and efficient solvent recycling to lower financial and environmental costs of large scale manufacturing.
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Affiliation(s)
- Lisa McQueen
- Drug Product Design and Development, GlaxoSmithKline, Collegeville, PA, United States
| | - David Lai
- Product and Process Engineering, GlaxoSmithKline, Collegeville, PA, United States.,Advanced Manufacturing Technologies, GlaxoSmithKline, Collegeville, PA, United States
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10
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Vossoughi A, Matthew HWT. Encapsulation of mesenchymal stem cells in glycosaminoglycans-chitosan polyelectrolyte microcapsules using electrospraying technique: Investigating capsule morphology and cell viability. Bioeng Transl Med 2018; 3:265-274. [PMID: 30377665 PMCID: PMC6195902 DOI: 10.1002/btm2.10111] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2018] [Revised: 08/08/2018] [Accepted: 08/11/2018] [Indexed: 12/18/2022] Open
Abstract
Polyelectrolyte microcapsules are modular constructs which facilitate cell handling and assembly of cell‐based tissue constructs. In this study, an electrospray (ES) encapsulation apparatus was developed for the encapsulation of mesenchymal stem cells (MSCs). Ionic complexation between glycosaminoglycans (GAGs) and chitosan formed a polyelectrolyte complex membrane at the interface. To optimize the capsules, the effect of voltage, needle size and GAG formulation on capsule size were investigated. It was observed that by increasing the voltage and decreasing the needle size, the capsule size would decrease but at voltages above 12 kV, capsule size distribution broadened significantly which yields lower circularity. Increase in GAG viscosity resulted in larger microcapsules and cell viability exhibited no significant changes during the encapsulation procedure. These results suggest that ES is a highly efficient, and scalable approach to the encapsulation of MSCs for subsequent use in bioprinting and other modular tissue engineering or regenerative medicine applications.
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Affiliation(s)
- Amin Vossoughi
- Dept. of Chemical Engineering and Material Science Wayne State University Detroit MI 48202
| | - Howard W T Matthew
- Dept. of Chemical Engineering and Material Science Wayne State University Detroit MI 48202
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11
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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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12
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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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13
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14
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Hennek JW, Kumar AA, Wiltschko AB, Patton MR, Lee SYR, Brugnara C, Adams RP, Whitesides GM. Diagnosis of iron deficiency anemia using density-based fractionation of red blood cells. LAB ON A CHIP 2016; 16:3929-3939. [PMID: 27713998 DOI: 10.1039/c6lc00875e] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Iron deficiency anemia (IDA) is a nutritional disorder that impacts over one billion people worldwide; it may cause permanent cognitive impairment in children, fatigue in adults, and suboptimal outcomes in pregnancy. IDA can be diagnosed by detection of red blood cells (RBCs) that are characteristically small (microcytic) and deficient in hemoglobin (hypochromic), typically by examining the results of a complete blood count performed by a hematology analyzer. These instruments are expensive, not portable, and require trained personnel; they are, therefore, unavailable in many low-resource settings. This paper describes a low-cost and rapid method to diagnose IDA using aqueous multiphase systems (AMPS)-thermodynamically stable mixtures of biocompatible polymers and salt that spontaneously form discrete layers having sharp steps in density. AMPS are preloaded into a microhematocrit tube and used with a drop of blood from a fingerstick. After only two minutes in a low-cost centrifuge, the tests (n = 152) were read by eye with a sensitivity of 84% (72-93%) and a specificity of 78% (68-86%), corresponding to an area under the curve (AUC) of 0.89. The AMPS test outperforms diagnosis by hemoglobin alone (AUC = 0.73) and is comparable to methods used in clinics like reticulocyte hemoglobin concentration (AUC = 0.91). Standard machine learning tools were used to analyze images of the resulting tests captured by a standard desktop scanner to 1) slightly improve diagnosis of IDA-sensitivity of 90% (83-96%) and a specificity of 77% (64-87%), and 2) predict several important red blood cell parameters, such as mean corpuscular hemoglobin concentration. These results suggest that the use of AMPS combined with machine learning provides an approach to developing point-of-care hematology.
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Affiliation(s)
| | | | - Alex B Wiltschko
- School of Engineering and Applied Sciences, USA and Department of Neurobiology, Harvard Medical School, USA
| | | | | | - Carlo Brugnara
- Department of Laboratory Medicine, Boston Children's Hospital and Department of Pathology, Harvard Medical School, USA.
| | | | - George M Whitesides
- Department of Chemistry and Chemical Biology, USA and Wyss Institute for Biologically Inspired Engineering, USA
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15
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Soares RRG, Silva DFC, Fernandes P, Azevedo AM, Chu V, Conde JP, Aires-Barros MR. Miniaturization of aqueous two-phase extraction for biological applications: From micro-tubes to microchannels. Biotechnol J 2016; 11:1498-1512. [PMID: 27624685 DOI: 10.1002/biot.201600356] [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] [Received: 05/25/2016] [Revised: 07/20/2016] [Accepted: 07/25/2016] [Indexed: 01/26/2023]
Abstract
Aqueous two-phase extraction (ATPE) is a biocompatible liquid-liquid (L-L) separation technique that has been under research for several decades towards the purification of biomolecules, ranging from small metabolites to large animal cells. More recently, with the emergence of rapid-prototyping techniques for fabrication of microfluidic structures with intricate designs, ATPE gained an expanded range of applications utilizing physical phenomena occurring exclusively at the microscale. Today, research is being carried simultaneously in two different volume ranges, mL-scale (microtubes) and nL-scale (microchannels). The objective of this review is to give insight into the state of the art at both microtube and microchannel-scale and to analyze whether miniaturization is currently a competing or divergent technology in a field of applications including bioseparation, bioanalytics, enhanced fermentation processes, catalysis, high-throughput screening and physical/chemical compartmentalization. From our perspective, both approaches are worthy of investigation and, depending on the application, it is likely that either (i) one of the approaches will eventually become obsolete in particular research areas such as purification at the preparative scale or high-throughput screening applications; or (ii) both approaches will function as complementing techniques within the bioanalytics field.
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Affiliation(s)
- Ruben R G Soares
- Instituto de Engenharia de Sistemas e Computadores - Microsistemas e Nanotecnologias (INESC MN) and IN - Institute of Nanoscience and Nanotechnology, Lisbon, Portugal.,IBB - Institute for Bioengineering and Biosciences, Instituto Superior Técnico, Universidade de Lisboa, Lisbon, Portugal
| | - Daniel F C Silva
- Instituto de Engenharia de Sistemas e Computadores - Microsistemas e Nanotecnologias (INESC MN) and IN - Institute of Nanoscience and Nanotechnology, Lisbon, Portugal.,IBB - Institute for Bioengineering and Biosciences, Instituto Superior Técnico, Universidade de Lisboa, Lisbon, Portugal
| | - Pedro Fernandes
- IBB - Institute for Bioengineering and Biosciences, Instituto Superior Técnico, Universidade de Lisboa, Lisbon, Portugal.,Department of Bioengineering, Instituto Superior Técnico, Universidade de Lisboa, Lisbon, Portugal
| | - Ana M Azevedo
- IBB - Institute for Bioengineering and Biosciences, Instituto Superior Técnico, Universidade de Lisboa, Lisbon, Portugal.,Department of Bioengineering, Instituto Superior Técnico, Universidade de Lisboa, Lisbon, Portugal
| | - Virginia Chu
- Instituto de Engenharia de Sistemas e Computadores - Microsistemas e Nanotecnologias (INESC MN) and IN - Institute of Nanoscience and Nanotechnology, Lisbon, Portugal
| | - João P Conde
- Instituto de Engenharia de Sistemas e Computadores - Microsistemas e Nanotecnologias (INESC MN) and IN - Institute of Nanoscience and Nanotechnology, Lisbon, Portugal.,Department of Bioengineering, Instituto Superior Técnico, Universidade de Lisboa, Lisbon, Portugal
| | - M Raquel Aires-Barros
- IBB - Institute for Bioengineering and Biosciences, Instituto Superior Técnico, Universidade de Lisboa, Lisbon, Portugal.,Department of Bioengineering, Instituto Superior Técnico, Universidade de Lisboa, Lisbon, Portugal
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16
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Zaslavsky BY, Uversky VN, Chait A. Analytical applications of partitioning in aqueous two-phase systems: Exploring protein structural changes and protein–partner interactions in vitro and in vivo by solvent interaction analysis method. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2016; 1864:622-44. [DOI: 10.1016/j.bbapap.2016.02.017] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/13/2016] [Revised: 02/16/2016] [Accepted: 02/21/2016] [Indexed: 12/29/2022]
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17
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Moon BU, Jones SG, Hwang DK, Tsai SSH. Microfluidic generation of aqueous two-phase system (ATPS) droplets by controlled pulsating inlet pressures. LAB ON A CHIP 2015; 15:2437-44. [PMID: 25906146 DOI: 10.1039/c5lc00217f] [Citation(s) in RCA: 68] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
We present a technique that generates droplets using ultralow interfacial tension aqueous two-phase systems (ATPS). Our method combines a classical microfluidic flow focusing geometry with precisely controlled pulsating inlet pressure, to form monodisperse ATPS droplets. The dextran (DEX) disperse phase enters through the central inlet with variable on-off pressure cycles controlled by a pneumatic solenoid valve. The continuous phase polyethylene glycol (PEG) solution enters the flow focusing junction through the cross channels at a fixed flow rate. The on-off cycles of the applied pressure, combined with the fixed flow rate cross flow, make it possible for the ATPS jet to break up into droplets. We observe different droplet formation regimes with changes in the applied pressure magnitude and timing, and the continuous phase flow rate. We also develop a scaling model to predict the size of the generated droplets, and the experimental results show a good quantitative agreement with our scaling model. Additionally, we demonstrate the potential for scaling-up of the droplet production rate, with a simultaneous two-droplet generating geometry. We anticipate that this simple and precise approach to making ATPS droplets will find utility in biological applications where the all-biocompatibility of ATPS is desirable.
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Affiliation(s)
- Byeong-Ui Moon
- Ryerson University, Mechanical and Industrial Engineering, Toronto, Canada.
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18
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Das D, Duraiswamy S, Yi Z, Chan V, Yang C. Continuous Droplet-Based Liquid-Liquid Extraction of Phenol from Oil. SEP SCI TECHNOL 2015. [DOI: 10.1080/01496395.2014.978466] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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19
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Kumar AA, Lim C, Moreno Y, Mace CR, Syed A, Van Tyne D, Wirth DF, Duraisingh MT, Whitesides GM. Enrichment of reticulocytes from whole blood using aqueous multiphase systems of polymers. Am J Hematol 2015; 90:31-6. [PMID: 25263455 DOI: 10.1002/ajh.23860] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2014] [Accepted: 09/24/2014] [Indexed: 01/10/2023]
Abstract
This paper demonstrates the enrichment of reticulocytes by centrifuging whole blood through aqueous multiphase systems (AMPSs)-immiscible phases of solutions of polymers that form step-gradients in density. The interfaces of an AMPS concentrate cells; this concentration facilitates the extraction of blood enriched for reticulocytes. AMPS enrich reticulocytes from blood from both healthy and hemochromatosis donors. Varying the osmolality and density of the phases of AMPS provides different levels of enrichment and yield of reticulocytes. A maximum enrichment of reticulocytemia of 64 ± 3% was obtained from donors with hemochromatosis. When used on peripheral blood from normal donors, AMPS can provide a higher yield of enriched reticulocytes and a higher proportion of reticulocytes expressing CD71 than differential centrifugation followed by centrifugation over Percoll. Blood enriched for reticulocytes by AMPS could be useful for research on malaria. Several species of malaria parasites show a preference to invade young erythrocytes and reticulocytes; this preference complicates in vitro cultivation of these species in human blood. Plasmodium knowlesi malaria parasites invade normal human blood enriched for reticulocytes by AMPSs at a rate 2.2 times greater (P < 0.01) than they invade unenriched blood. Parasite invasion in normal blood enriched by AMPS was 1.8 times greater (P < 0.05) than in blood enriched to a similar reticulocytemia by differential centrifugation followed by centrifugation over Percoll. The enrichment of reticulocytes that are invaded by malaria parasites demonstrates that AMPSs can provide a label-free method to enrich cells for biological research.
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Affiliation(s)
- Ashok A. Kumar
- School of Engineering and Applied Sciences; Harvard University; Cambridge Massachusetts
| | - Caeul Lim
- Harvard School of Public Health; Harvard University; Boston Massachusetts
| | - Yovany Moreno
- Harvard School of Public Health; Harvard University; Boston Massachusetts
| | - Charles R. Mace
- Department of Chemistry and Chemical Biology; Harvard University; Cambridge Massachusetts
| | - Abeer Syed
- Department of Chemistry and Chemical Biology; Harvard University; Cambridge Massachusetts
| | - Daria Van Tyne
- Harvard School of Public Health; Harvard University; Boston Massachusetts
| | - Dyann F. Wirth
- Harvard School of Public Health; Harvard University; Boston Massachusetts
| | | | - George M. Whitesides
- Department of Chemistry and Chemical Biology; Harvard University; Cambridge Massachusetts
- Wyss Institute for Biologically Inspired Engineering; Harvard University; Cambridge Massachusetts
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20
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Oil–water biphasic parallel flow for the precise patterning of metals and cells. Biomed Microdevices 2013; 16:245-53. [DOI: 10.1007/s10544-013-9828-y] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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21
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Tarn MD, Lopez-Martinez MJ, Pamme N. On-chip processing of particles and cells via multilaminar flow streams. Anal Bioanal Chem 2013; 406:139-61. [DOI: 10.1007/s00216-013-7363-6] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2013] [Revised: 09/09/2013] [Accepted: 09/10/2013] [Indexed: 10/26/2022]
Affiliation(s)
- Mark D Tarn
- Department of Chemistry, The University of Hull, Cottingham Road, Hull, HU6 7RX, UK
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22
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DelNero P, Song YH, Fischbach C. Microengineered tumor models: insights & opportunities from a physical sciences-oncology perspective. Biomed Microdevices 2013; 15:583-593. [PMID: 23559404 PMCID: PMC3714360 DOI: 10.1007/s10544-013-9763-y] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Prevailing evidence has established the fundamental role of microenvironmental conditions in tumorigenesis. However, the ability to identify, interrupt, and translate the underlying cellular and molecular mechanisms into meaningful therapies remains limited, due in part to a lack of organotypic culture systems that accurately recapitulate tumor physiology. Integration of tissue engineering with microfabrication technologies has the potential to address this challenge and mimic tumor heterogeneity with pathological fidelity. Specifically, this approach allows recapitulating global changes of tissue-level phenomena, while also controlling microscale variability of various conditions including spatiotemporal presentation of soluble signals, biochemical and physical characteristics of the extracellular matrix, and cellular composition. Such platforms have continued to elucidate the role of the microenvironment in cancer pathogenesis and significantly improve drug discovery and screening, particularly for therapies that target tumor-enabling stromal components. This review discusses some of the landmark efforts in the field of micro-tumor engineering with a particular emphasis on deregulated tissue organization and mass transport phenomena in the tumor microenvironment.
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Affiliation(s)
- Peter DelNero
- Department of Biomedical Engineering, Cornell University, Ithaca, NY, 14853, USA
| | - Young Hye Song
- Department of Biomedical Engineering, Cornell University, Ithaca, NY, 14853, USA
| | - Claudia Fischbach
- Department of Biomedical Engineering, Cornell University, Ithaca, NY, 14853, USA.
- Kavli Institute at Cornell for Nanoscale Science, Cornell University, Ithaca, NY, 14853, USA.
- , 157 Weill Hall, Ithaca, NY, 14853, USA.
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Boreyko JB, Mruetusatorn P, Retterer ST, Collier CP. Aqueous two-phase microdroplets with reversible phase transitions. LAB ON A CHIP 2013; 13:1295-301. [PMID: 23381219 DOI: 10.1039/c3lc41122b] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
Aqueous two-phase systems contained within microdroplets enable a bottom-up approach to mimicking the dynamic microcompartmentation of biomaterial that naturally occurs within the cytoplasm of cells. Here, we demonstrate the generation of femtolitre aqueous two-phase droplets within a microfluidic oil channel. Gated pressure pulses were used to generate individual, stationary two-phase microdroplets with a well-defined time zero for carrying out controlled and sequential phase transformations over time. Reversible phase transitions between single-phase, two-phase, and core-shell microbead states were obtained via evaporation-induced dehydration and water rehydration. In contrast to other microfluidic aqueous two-phase droplets, which require continuous flows and high-frequency droplet formation, our system enables the controlled isolation and reversible transformation of a single microdroplet and is expected to be useful for future studies in dynamic microcompartmentation and affinity partitioning.
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Affiliation(s)
- Jonathan B Boreyko
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, TN 37831-6493, USA
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Frampton JP, White JB, Abraham AT, Takayama S. Cell co-culture patterning using aqueous two-phase systems. J Vis Exp 2013. [PMID: 23567187 DOI: 10.3791/50304] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
Cell patterning technologies that are fast, easy to use and affordable will be required for the future development of high throughput cell assays, platforms for studying cell-cell interactions and tissue engineered systems. This detailed protocol describes a method for generating co-cultures of cells using biocompatible solutions of dextran (DEX) and polyethylene glycol (PEG) that phase-separate when combined above threshold concentrations. Cells can be patterned in a variety of configurations using this method. Cell exclusion patterning can be performed by printing droplets of DEX on a substrate and covering them with a solution of PEG containing cells. The interfacial tension formed between the two polymer solutions causes cells to fall around the outside of the DEX droplet and form a circular clearing that can be used for migration assays. Cell islands can be patterned by dispensing a cell-rich DEX phase into a PEG solution or by covering the DEX droplet with a solution of PEG. Co-cultures can be formed directly by combining cell exclusion with DEX island patterning. These methods are compatible with a variety of liquid handling approaches, including manual micropipetting, and can be used with virtually any adherent cell type.
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Affiliation(s)
- John P Frampton
- Department of Biomedical Engineering, University of Michigan, Michigan, USA
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Bathany C, Park J, Cho YK, Takayama S. Dehydrated aqueous two-phase system micro-domains retain their shape upon rehydration to allow patterned reagent delivery to cells. J Mater Chem B 2013; 1:6020-6026. [DOI: 10.1039/c3tb21004a] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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Geschiere SD, Ziemecka I, van Steijn V, Koper GJM, Esch JHV, Kreutzer MT. Slow growth of the Rayleigh-Plateau instability in aqueous two phase systems. BIOMICROFLUIDICS 2012; 6:22007-2200711. [PMID: 22536307 PMCID: PMC3331863 DOI: 10.1063/1.3700117] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/23/2011] [Accepted: 03/18/2012] [Indexed: 05/11/2023]
Abstract
This paper studies the Rayleigh-Plateau instability for co-flowing immiscible aqueous polymer solutions in a microfluidic channel. Careful vibration-free experiments with controlled actuation of the flow allowed direct measurement of the growth rate of this instability. Experiments for the well-known aqueous two phase system (ATPS, or aqueous biphasic systems) of dextran and polyethylene glycol solutions exhibited a growth rate of 1 s(-1), which was more than an order of magnitude slower than an analogous experiment with two immiscible Newtonian fluids with viscosities and interfacial tension that closely matched the ATPS experiment. Viscoelastic effects and adhesion to the walls were ruled out as explanations for the observed behavior. The results are remarkable because all current theory suggests that such dilute polymer solutions should break up faster, not slower, than the analogous Newtonian case. Microfluidic uses of aqueous two phase systems include separation of labile biomolecules but have hitherto be limited because of the difficulty in making droplets. The results of this work teach how to design devices for biological microfluidic ATPS platforms.
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Mace CR, Akbulut O, Kumar AA, Shapiro ND, Derda R, Patton MR, Whitesides GM. Aqueous multiphase systems of polymers and surfactants provide self-assembling step-gradients in density. J Am Chem Soc 2012; 134:9094-7. [PMID: 22594904 DOI: 10.1021/ja303183z] [Citation(s) in RCA: 93] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
This Communication demonstrates the generation of over 300 phase-separated systems-ranging from two to six phases-from mixtures of aqueous solutions of polymers and surfactants. These aqueous multiphase systems (MuPSs) form self-assembling, thermodynamically stable step-gradients in density using a common solvent, water. The steps in density between phases of a MuPS can be very small (Δρ ≈ 0.001 g/cm(3)), do not change over time, and can be tuned by the addition of co-solutes. We use two sets of similar objects, glass beads and pellets of different formulations of Nylon, to demonstrate the ability of MuPSs to separate mixtures of objects by differences in density. The stable interfaces between phases facilitate the convenient collection of species after separation. These results suggest that the stable, sharp step-gradients in density provided by MuPSs can enable new classes of fractionations and separations based on density.
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Affiliation(s)
- Charles R Mace
- Department of Chemistry & Chemical Biology, Harvard University, Cambridge, Massachusetts 02138, United States
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Fang Y, Frampton JP, Raghavan S, Sabahi-Kaviani R, Luker G, Deng CX, Takayama S. Rapid generation of multiplexed cell cocultures using acoustic droplet ejection followed by aqueous two-phase exclusion patterning. Tissue Eng Part C Methods 2012; 18:647-57. [PMID: 22356298 DOI: 10.1089/ten.tec.2011.0709] [Citation(s) in RCA: 76] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
The development of tools for patterning cocultures of cells is a fundamental interest among cell biologists and tissue engineers. Although a variety of systems exist for micropatterning cells, the methods used to generate cell micropatterns are often cumbersome and difficult to adapt for tissue engineering purposes. This study combines acoustic droplet ejection and aqueous two-phase system exclusion patterning to introduce a method for patterning cocultures of cells in multiplexed arrays. This new method uses focused acoustic radiation pressure to eject discrete droplets of uniform size from the surface of a dextran solution containing cells. The size of droplets is controlled by adjusting ultrasound parameters, such as pulse, duration, and amplitude. The ejected dextran droplets are captured on a cell culture substrate that is manipulated by a computer-controlled 3D positioning system according to predesigned patterns. Polyethylene glycol solution containing an additional cell type is then added to the culture dish to produce a two-phase system capable of depositing different types of cells around the initial pattern of cells. We demonstrate that our method can produce patterns of islands or lines with two or more cell types. Further, we demonstrate that patterns can be multiplexed for studies involving combinations of multiple cell types. This method offers a tool to transfer cell-containing samples in a contact-free, nozzle-less manner, avoiding sample cross-contamination. It can be used to pattern cell cocultures without complicated fabrication of culture substrates. These capabilities were used to examine the response of cancer cells to the presence of a ligand (CXCL12) secreted from surrounding cocultured cells.
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Affiliation(s)
- Yu Fang
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI 48104, USA
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Lai D, Frampton JP, Sriram H, Takayama S. Rounded multi-level microchannels with orifices made in one exposure enable aqueous two-phase system droplet microfluidics. LAB ON A CHIP 2011; 11:3551-4. [PMID: 21892481 DOI: 10.1039/c1lc20560a] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
Exposure of a negative photoresist-coated glass slide with diffused light from the backside through a mask with disconnected features provides multi-level rounded channels with narrow orifices in one exposure. Using these structures, we construct microfluidic systems capable of creating aqueous two-phase system droplets where one aqueous phase forms droplets and the other aqueous phase forms the surrounding matrix. Unlike water-in-oil droplet systems, aqueous two-phase systems can have very low interfacial tensions that prevent spontaneous droplet formation. The multi-level channels fabricated by backside lithography satisfy two conflicting needs: (i) the requirement to have narrowed channels for efficient valve closure by channel deformation and (ii) the need to have wide channels to reduce the flow velocity, thus reducing the capillary number and enhancing droplet formation.
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Affiliation(s)
- David Lai
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI, USA
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