1
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Daly AC. Granular Hydrogels in Biofabrication: Recent Advances and Future Perspectives. Adv Healthc Mater 2024; 13:e2301388. [PMID: 37317658 DOI: 10.1002/adhm.202301388] [Citation(s) in RCA: 13] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2023] [Revised: 06/10/2023] [Indexed: 06/16/2023]
Abstract
Granular hydrogels, which are formed by densely packing microgels, are promising materials for bioprinting due to their extrudability, porosity, and modularity. However, the multidimensional parameter space involved in granular hydrogel design makes material optimization challenging. For example, design inputs such as microgel morphology, packing density, or stiffness can influence multiple rheological properties that govern printability and the behavior of encapsulated cells. This review provides an overview of fabrication methods for granular hydrogels, and then examines how important design inputs can influence material properties associated with printability and cellular responses across multiple scales. Recent applications of granular design principles in bioink engineering are described, including the development of granular support hydrogels for embedded printing. Further, the paper provides an overview of how key physical properties of granular hydrogels can influence cellular responses, highlighting the advantages of granular materials for promoting cell and tissue maturation after the printing process. Finally, potential future directions for advancing the design of granular hydrogels for bioprinting are discussed.
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Affiliation(s)
- Andrew C Daly
- Biomedical Engineering, University of Galway, Galway, H91 TK33, Ireland
- CÚRAM the Science Foundation Ireland Research Centre for Medical Devices, University of Galway, Galway, H91 TK33, Ireland
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2
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Feliciano AJ, Alaoui Selsouli Y, Habibovic P, Birgani ZNT, Moroni L, Baker MB. Granular polyrotaxane microgels as injectable hydrogels for corneal tissue regeneration. Biomater Sci 2024; 12:4993-5009. [PMID: 39169887 DOI: 10.1039/d4bm00409d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/23/2024]
Abstract
Corneal diseases, a leading cause of global vision impairment, present challenges in treatment due to corneal tissue donor scarcity and transplant rejection. Hydrogel biomaterials in the form of corneal implants for tissue regeneration, while promising, have faced obstacles related to cellular and tissue integration. This study develops and investigates the potential of granular polyrotaxane (GPR) hydrogels as a scaffold for corneal keratocyte growth and transparent tissue generation. Employing host-guest driven supramolecular interactions, we developed injectable, cytocompatible hydrogels. By optimizing cyclodextrin (CD) concentrations in thiol-ene crosslinked PEG microgels, we observed improved mechanical properties and thermoresponsiveness while preserving injectability. These microgels, adaptable for precise defect filling, 3D printing or tissue culture facilitate enhanced cellular integration with corneal keratocytes and exhibit tissue-like structures in culture. Our findings demonstrate the promise of GPR hydrogels as a minimally invasive avenue for corneal tissue regeneration. These results have the potential to address transplantation challenges, enhance clinical outcomes, and restore vision.
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Affiliation(s)
- Antonio J Feliciano
- Department of Complex Tissue Regeneration, Maastricht University, MERLN Institute for Technology-Inspired Regenerative Medicine, Maastricht, the Netherlands.
| | - Yousra Alaoui Selsouli
- Department of Instructive Biomaterial Engineering, Maastricht University, MERLN Institute for Technology-Inspired Regenerative Medicine, Maastricht, the Netherlands
| | - Pamela Habibovic
- Department of Instructive Biomaterial Engineering, Maastricht University, MERLN Institute for Technology-Inspired Regenerative Medicine, Maastricht, the Netherlands
| | - Zeinab Niloofar Tahmasebi Birgani
- Department of Complex Tissue Regeneration, Maastricht University, MERLN Institute for Technology-Inspired Regenerative Medicine, Maastricht, the Netherlands.
- Department of Instructive Biomaterial Engineering, Maastricht University, MERLN Institute for Technology-Inspired Regenerative Medicine, Maastricht, the Netherlands
| | - Lorenzo Moroni
- Department of Complex Tissue Regeneration, Maastricht University, MERLN Institute for Technology-Inspired Regenerative Medicine, Maastricht, the Netherlands.
| | - Matthew B Baker
- Department of Complex Tissue Regeneration, Maastricht University, MERLN Institute for Technology-Inspired Regenerative Medicine, Maastricht, the Netherlands.
- Department of Instructive Biomaterial Engineering, Maastricht University, MERLN Institute for Technology-Inspired Regenerative Medicine, Maastricht, the Netherlands
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3
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Xu X, Tang Q, Gao Y, Chen S, Yu Y, Qian H, McClements DJ, Cao C, Yuan B. Recent developments in the fabrication of food microparticles and nanoparticles using microfluidic systems. Crit Rev Food Sci Nutr 2024:1-15. [PMID: 38520155 DOI: 10.1080/10408398.2024.2329967] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/25/2024]
Abstract
Microfluidics is revolutionizing the production of microparticles and nanoparticles, offering precise control over dimensions and internal structure. This technology facilitates the creation of colloidal delivery systems capable of encapsulating and releasing nutraceuticals. Nutraceuticals, often derived from food-grade ingredients, can be used for developing functional foods. This review focuses on the principles and applications of microfluidic systems in crafting colloidal delivery systems for nutraceuticals. It explores the foundational principles behind the development of microfluidic devices for nutraceutical encapsulation and delivery. Additionally, it examines the prospects and challenges with using microfluidics for functional food development. Microfluidic systems can be employed to form emulsions, liposomes, microgels and microspheres, by manipulating minute volumes of fluids flowing within microchannels. This versatility can enhance the dispersibility, stability, and bioavailability of nutraceuticals. However, challenges as scaling up production, fabrication complexity, and microchannel clogging hinder the widespread application of microfluidic technologies. In conclusion, this review highlights the potential role of microfluidics in design and fabrication of nutraceutical delivery systems. At present, this technology is most suitable for exploring the role of specific delivery system features (such as particle size, composition and morphology) on the stability and bioavailability of nutraceuticals, rather than for large-scale production of nutraceutical delivery systems.
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Affiliation(s)
- Xiao Xu
- School of Life Science, Shaoxing University, Shaoxing, Zhejiang, China
| | - Qi Tang
- School of Life Science, Shaoxing University, Shaoxing, Zhejiang, China
- Department of Food Quality and Safety/National R&D Center for Chinese Herbal Medicine Processing, College of Engineering, China Pharmaceutical University, Nanjing, Jiangsu, China
| | - Yating Gao
- Department of Food Quality and Safety/National R&D Center for Chinese Herbal Medicine Processing, College of Engineering, China Pharmaceutical University, Nanjing, Jiangsu, China
| | - Shaoqin Chen
- School of Life Science, Shaoxing University, Shaoxing, Zhejiang, China
| | - Yingying Yu
- School of Life Science, Shaoxing University, Shaoxing, Zhejiang, China
| | - Hongliang Qian
- Department of Food Quality and Safety/National R&D Center for Chinese Herbal Medicine Processing, College of Engineering, China Pharmaceutical University, Nanjing, Jiangsu, China
| | | | - Chongjiang Cao
- Department of Food Quality and Safety/National R&D Center for Chinese Herbal Medicine Processing, College of Engineering, China Pharmaceutical University, Nanjing, Jiangsu, China
| | - Biao Yuan
- Department of Food Quality and Safety/National R&D Center for Chinese Herbal Medicine Processing, College of Engineering, China Pharmaceutical University, Nanjing, Jiangsu, China
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4
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Sommerfeld IK, Malyaran H, Neuss S, Demco DE, Pich A. Multiresponsive Core-Shell Microgels Functionalized by Nitrilotriacetic Acid. Biomacromolecules 2024; 25:903-923. [PMID: 38170471 DOI: 10.1021/acs.biomac.3c01056] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2024]
Abstract
Stimuli-responsive microgels with ionizable functional groups offer versatile applications, e.g., by the uptake of oppositely charged metal ions or guest molecules such as drugs, dyes, or proteins. Furthermore, the incorporation of carboxylic groups enhances mucoadhesive properties, crucial for various drug delivery applications. In this work, we successfully synthesized poly{N-vinylcaprolactam-2,2'-[(5-acrylamido-1-carboxypentyl)azanediyl]diacetic acid} [p(VCL/NTAaa)] microgels containing varying amounts of nitrilotriacetic acid (NTA) using precipitation polymerization. We performed fundamental characterization by infrared (IR) spectroscopy and dynamic and electrophoretic light scattering. Despite their potential multiresponsiveness, prior studies on NTA-functionalized microgels lack in-depth analysis of their stimuli-responsive behavior. This work addresses this gap by assessing the microgel responsiveness to temperature, ionic strength, and pH. Morphological investigations were performed via NMR relaxometry, nanoscale imaging (AFM and SEM), and reaction calorimetry. Finally, we explored the potential application of the microgels by conducting cytocompatibility experiments and demonstrating the immobilization of the model protein cytochrome c in the microgels.
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Affiliation(s)
- Isabel K Sommerfeld
- Functional and Interactive Polymers, Institute of Technical and Macromolecular Chemistry, RWTH Aachen University, Worringerweg 2, 52074 Aachen, Germany
- DWI─Leibniz-Institute for Interactive Materials e.V., Forckenbeckstraße 50, 52074 Aachen, Germany
| | - Hanna Malyaran
- Interdisciplinary Center for Clinical Research (IZKF), RWTH Aachen University, Pauwelsstraße 30, 52074 Aachen, Germany
- Helmholtz Institute for Biomedical Engineering, BioInterface Group, RWTH Aachen University, Pauwelsstraße 30, 52074 Aachen, Germany
- Department of Orthodontics, University Hospital of RWTH Aachen, Pauwelsstraße 30, 52074 Aachen, Germany
| | - Sabine Neuss
- Helmholtz Institute for Biomedical Engineering, BioInterface Group, RWTH Aachen University, Pauwelsstraße 30, 52074 Aachen, Germany
- Institute of Pathology, RWTH Aachen University, Pauwelsstraße 30, 52074 Aachen, Germany
| | - Dan E Demco
- DWI─Leibniz-Institute for Interactive Materials e.V., Forckenbeckstraße 50, 52074 Aachen, Germany
| | - Andrij Pich
- Functional and Interactive Polymers, Institute of Technical and Macromolecular Chemistry, RWTH Aachen University, Worringerweg 2, 52074 Aachen, Germany
- DWI─Leibniz-Institute for Interactive Materials e.V., Forckenbeckstraße 50, 52074 Aachen, Germany
- Aachen Maastricht Institute for Biobased Materials (AMIBM), Maastricht University, Brightlands Chemelot Campus, Urmonderbaan 22, 6167 RD Geleen, The Netherlands
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5
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Wu Q, Huang X, Liu R, Yang X, Xiao G, Jiang N, Weitz DA, Song Y. Multichannel Multijunction Droplet Microfluidic Device to Synthesize Hydrogel Microcapsules with Different Core-Shell Structures and Adjustable Core Positions. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2024; 40:1950-1960. [PMID: 37991242 DOI: 10.1021/acs.langmuir.3c02579] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2023]
Abstract
Core-shell hydrogel microcapsules have sparked great interest due to their unique characteristics and prospective applications in the medical, pharmaceutical, and cosmetic fields. However, complex synthetic procedures and expensive costs have limited their practical application. Herein, we designed and prepared several multichannel and multijunctional droplet microfluidic devices based on soft lithography for the effective synthesis of core-shell hydrogel microcapsules for different purposes. Additionally, two different cross-linking processes (ultraviolet (UV) exposure and interfacial polymerization) were used to synthesize different types of core-shell structured hydrogel microcapsules. Hydrogel microcapsules with gelatin methacryloyl (GelMA) as the core and polyacrylamide (PAM) as the thin shell were synthesized using UV cross-linking. Using an interfacial polymerization process, another core-shell structured microcapsule with GelMA as the core and Ca2+ cross-linked alginate with polyethylenimine (PEI) as the shell was constructed, and the core diameter and total droplet diameter were flexibly controlled by carving. Noteworthy, these hydrogel microcapsules exhibit stimuli-responsiveness and controlled release ability. Overall, a novel technique was developed to successfully synthesize various hydrogel microcapsules with core-shell microstructures. The hydrogel microcapsules possess a multilayered structure that facilitates the coassembly of cells and drugs, as well as the layered assembly of multiple drugs, to develop synergistic therapeutic regimens. These adaptable and controllable hydrogel microdroplets shall held great promise for multicell or multidrug administration as well as for high-throughput drug screening.
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Affiliation(s)
- Qiong Wu
- Center for Modern Physics Technology, School of Mathematics and Physics, University of Science and Technology Beijing, Beijing 100083, China
| | - Xing Huang
- Physics Department, School of Engineering and Applied Science, Harvard University, Cambridge, Massachusetts 02138, United States
- Department of Mechanical Engineering, Hangzhou City University, Hangzhou 310015, China
- Zhejiang Provincial Engineering Center of Integrated Manufacturing Technology and Intelligent Equipment, Hangzhou City University, Hangzhou 310015, China
| | - Ran Liu
- Center for Modern Physics Technology, School of Mathematics and Physics, University of Science and Technology Beijing, Beijing 100083, China
- Zhengzhou Tianzhao Biomedical Technology Company Ltd., Zhengzhou 451450, China
- Key Laboratory of Pulsed Power Translational Medicine of Zhejiang Province, Hangzhou 310003, China
| | - Xinzhu Yang
- Center for Modern Physics Technology, School of Mathematics and Physics, University of Science and Technology Beijing, Beijing 100083, China
- Zhengzhou Tianzhao Biomedical Technology Company Ltd., Zhengzhou 451450, China
- Key Laboratory of Pulsed Power Translational Medicine of Zhejiang Province, Hangzhou 310003, China
| | - Gao Xiao
- Physics Department, School of Engineering and Applied Science, Harvard University, Cambridge, Massachusetts 02138, United States
- Department of Environmental Science and Engineering, College of Environment and Safety Engineering, Fuzhou University, Fuzhou 350108, China
| | - Nan Jiang
- Physics Department, School of Engineering and Applied Science, Harvard University, Cambridge, Massachusetts 02138, United States
- West China School of Basic Medical Sciences & Forensic Medicine, Sichuan University, Chengdu 610041, China
- JinFeng Laboratory, Chongqing 401329, China
| | - David A Weitz
- Physics Department, School of Engineering and Applied Science, Harvard University, Cambridge, Massachusetts 02138, United States
| | - Yujun Song
- Center for Modern Physics Technology, School of Mathematics and Physics, University of Science and Technology Beijing, Beijing 100083, China
- Physics Department, School of Engineering and Applied Science, Harvard University, Cambridge, Massachusetts 02138, United States
- Zhengzhou Tianzhao Biomedical Technology Company Ltd., Zhengzhou 451450, China
- Key Laboratory of Pulsed Power Translational Medicine of Zhejiang Province, Hangzhou 310003, China
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6
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Hengsbach R, Fink G, Simon U. 1H-NMR studies on the volume phase transition of DNA-modified pNipmam microgels. SOFT MATTER 2024; 20:330-337. [PMID: 38087892 DOI: 10.1039/d3sm01124k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2024]
Abstract
DNA functionalized pNipmam microgels, which have recently been introduced, are examined at different concentrations of sodium chloride and in PBS solutions via temperature dependent 1H-NMR measurements and are compared to pure pNipmam microgels. We show that the DNA modification shifts the volume phase transition temperature towards lower temperatures and the addition of salt and PBS further supports this effect in both materials. Thermodynamic values, i.e. enthalpy, entropy and Gibbs free energy, are determined via a non-linear fit which can be applied directly to the measurement data without further linearization.
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Affiliation(s)
- Rebecca Hengsbach
- Institute of Inorganic Chemistry, RWTH Aachen University, Landoltweg 1a, D-52074 Aachen, Germany.
| | - Gerhard Fink
- Institute of Inorganic Chemistry, RWTH Aachen University, Landoltweg 1a, D-52074 Aachen, Germany.
| | - Ulrich Simon
- Institute of Inorganic Chemistry, RWTH Aachen University, Landoltweg 1a, D-52074 Aachen, Germany.
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7
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Bochenek S, Rudov AA, Sassmann T, Potemkin II, Richtering W. Influence of Architecture on the Interfacial Properties of Polymers: Linear Chains, Stars, and Microgels. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2023; 39:18354-18365. [PMID: 38059308 DOI: 10.1021/acs.langmuir.3c02470] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/08/2023]
Abstract
Surface-active polymers have important applications as effective and responsive emulsifiers, foaming agents, and coatings. In this contribution, we explore the impact of the polymer architecture on the behavior at oil-water interfaces by comparing different poly(N-isopropylacrylamide) (pNIPAM)-based systems, namely, monolayers of linear and star-shaped macromolecules, ultralow cross-linked, regular cross-linked, and hollow microgels. Compression isotherms were determined experimentally as well as by computer simulations. The latter provides information about the conformational changes of the individual macromolecules as well as the interfacial properties of the monolayer, including the surface structure and the density distribution of an ensemble of interacting macromolecules near an interface. Surprisingly, the isotherms of the linear polymer, of the star polymer, and of the ultralow cross-linked microgel have an identical shape that differs from the isotherms of regular and hollow microgels. We introduced the mass fraction of adsorbed polymer, which gives a measure of the polymer segments contributing to the isotherm in relation to the most flexible architecture, i.e., the linear polymer, and allows a comparison of polymers with different architectures. The data demonstrate that increasing the number of cross-links leads to a significantly lower amount of polymer in the proximity of the interface as the increase in cross-linker reduces the deformability or softness of the polymers at the interface. The volume fraction profiles along the normal to the interface are essentially different in the microgel monolayers as compared to those in the linear and star polymer. The profiles through the microgel contact line and their growth upon initial compression are similar to those of the linear chains. Herewith, the profiles through the center of mass practically do not change upon compression. Therefore, the initial growth in the microgel surface pressure reveals the polymer-like behavior and is related to the deformation of the peripheral part of the microgel. Further compression of the microgel monolayer leads to 3D interactions of the microgels within the aqueous side of the interface and soft colloid-like behavior.
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Affiliation(s)
- Steffen Bochenek
- Institute of Physical Chemistry, RWTH Aachen University, Landoltweg 2, 52056 Aachen, Germany, European Union
| | - Andrey A Rudov
- DWI - Leibniz Institute for Interactive Materials, 52056 Aachen, Germany, European Union
| | - Tim Sassmann
- DWI - Leibniz Institute for Interactive Materials, 52056 Aachen, Germany, European Union
| | - Igor I Potemkin
- DWI - Leibniz Institute for Interactive Materials, 52056 Aachen, Germany, European Union
| | - Walter Richtering
- Institute of Physical Chemistry, RWTH Aachen University, Landoltweg 2, 52056 Aachen, Germany, European Union
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8
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Hu C, van Bonn P, Demco DE, Bolm C, Pich A. Mechanochemical Synthesis of Stimuli Responsive Microgels. Angew Chem Int Ed Engl 2023; 62:e202305783. [PMID: 37177824 DOI: 10.1002/anie.202305783] [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: 04/25/2023] [Revised: 05/12/2023] [Accepted: 05/12/2023] [Indexed: 05/15/2023]
Abstract
Mechanochemical approaches are widely used for the efficient, solvent-free synthesis of organic molecules, however their applicability to the synthesis of functional polymers has remained underexplored. Herein, we demonstrate for the first time that mechanochemically triggered free-radical polymerization allows solvent- and initiator-free syntheses of structurally and morphologically well-defined complex functional macromolecular architectures, namely stimuliresponsive microgels. The developed mechanochemical polymerization approach is applicable to a variety of monomers and allows synthesizing microgels with tunable chemical structure, variable size, controlled number of crosslinks and reactive functional end-groups.
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Affiliation(s)
- Chaolei Hu
- DWI-Leibniz Institute for Interactive Materials e.V., Forckenbeckstraße 50, 52074, Aachen, Germany
- Institute of Technical and Macromolecular Chemistry, RWTH Aachen University, Forckenbeckstraße 50, 52074, Aachen, Germany
| | - Pit van Bonn
- Institute of Organic Chemistry, RWTH Aachen University, Landoltweg 1, 52074, Aachen, Germany
| | - Dan E Demco
- DWI-Leibniz Institute for Interactive Materials e.V., Forckenbeckstraße 50, 52074, Aachen, Germany
| | - Carsten Bolm
- Institute of Organic Chemistry, RWTH Aachen University, Landoltweg 1, 52074, Aachen, Germany
| | - Andrij Pich
- DWI-Leibniz Institute for Interactive Materials e.V., Forckenbeckstraße 50, 52074, Aachen, Germany
- Institute of Technical and Macromolecular Chemistry, RWTH Aachen University, Forckenbeckstraße 50, 52074, Aachen, Germany
- Aachen Maastricht Institute for Biobased Materials (AMIBM), Maastricht University, Urmonderbaan 22, 6167 RD, Geleen, The Netherlands
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9
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Farooqi ZH, Vladisavljević GT, Pamme N, Fatima A, Begum R, Irfan A, Chen M. Microfluidic Fabrication and Applications of Microgels and Hybrid Microgels. Crit Rev Anal Chem 2023; 54:2435-2449. [PMID: 36757081 DOI: 10.1080/10408347.2023.2177097] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/10/2023]
Abstract
Smart microgels have gained much attention because of their wide range of applications in the field of biomedical, environmental, nanotechnological and catalysis sciences. Most of the applications of microgels are strongly affected by their morphology, size and size distribution. Various methodologies have been adopted to obtain polymer microgel particles. Droplet microfluidic techniques have been widely reported for the fabrication of highly monodisperse microgel particles to be used for various applications. Monodisperse microgel particles of required size and morphology can be achieved via droplet microfluidic techniques by simple polymerization of monomers in the presence of suitable crosslinker or by gelation of high molecular weight polymers. This report gives recent research progress in fabrication, characterization, properties and applications of microgel particles synthesized by microfluidic methods.
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Affiliation(s)
- Zahoor H Farooqi
- School of Chemistry, University of the Punjab, New Campus, Lahore, Pakistan
- Department of Chemical Engineering, Loughborough University, Loughborough, UK
| | | | - Nicole Pamme
- Department for Materials and Environmental Chemistry, Stockholm University, Stockholm, Sweden
- Department of Chemistry and Biochemistry, University of Hull, Hull, United Kingdom
| | - Arooj Fatima
- School of Chemistry, University of the Punjab, New Campus, Lahore, Pakistan
| | - Robina Begum
- School of Chemistry, University of the Punjab, New Campus, Lahore, Pakistan
| | - Ahmad Irfan
- Research Center for Advanced Materials Science (RCAMS), King Khalid University, Abha, Saudi Arabia
- Department of Chemistry, College of Science, King Khalid University, Abha, Saudi Arabia
| | - Minjun Chen
- Department of Chemical Engineering, Loughborough University, Loughborough, UK
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10
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Rojek K, Ćwiklińska M, Kuczak J, Guzowski J. Microfluidic Formulation of Topological Hydrogels for Microtissue Engineering. Chem Rev 2022; 122:16839-16909. [PMID: 36108106 PMCID: PMC9706502 DOI: 10.1021/acs.chemrev.1c00798] [Citation(s) in RCA: 40] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2021] [Indexed: 02/07/2023]
Abstract
Microfluidics has recently emerged as a powerful tool in generation of submillimeter-sized cell aggregates capable of performing tissue-specific functions, so-called microtissues, for applications in drug testing, regenerative medicine, and cell therapies. In this work, we review the most recent advances in the field, with particular focus on the formulation of cell-encapsulating microgels of small "dimensionalities": "0D" (particles), "1D" (fibers), "2D" (sheets), etc., and with nontrivial internal topologies, typically consisting of multiple compartments loaded with different types of cells and/or biopolymers. Such structures, which we refer to as topological hydrogels or topological microgels (examples including core-shell or Janus microbeads and microfibers, hollow or porous microstructures, or granular hydrogels) can be precisely tailored with high reproducibility and throughput by using microfluidics and used to provide controlled "initial conditions" for cell proliferation and maturation into functional tissue-like microstructures. Microfluidic methods of formulation of topological biomaterials have enabled significant progress in engineering of miniature tissues and organs, such as pancreas, liver, muscle, bone, heart, neural tissue, or vasculature, as well as in fabrication of tailored microenvironments for stem-cell expansion and differentiation, or in cancer modeling, including generation of vascularized tumors for personalized drug testing. We review the available microfluidic fabrication methods by exploiting various cross-linking mechanisms and various routes toward compartmentalization and critically discuss the available tissue-specific applications. Finally, we list the remaining challenges such as simplification of the microfluidic workflow for its widespread use in biomedical research, bench-to-bedside transition including production upscaling, further in vivo validation, generation of more precise organ-like models, as well as incorporation of induced pluripotent stem cells as a step toward clinical applications.
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Affiliation(s)
- Katarzyna
O. Rojek
- Institute of Physical Chemistry, Polish Academy of Sciences, ul. Kasprzaka 44/52, 01-224 Warsaw, Poland
| | - Monika Ćwiklińska
- Institute of Physical Chemistry, Polish Academy of Sciences, ul. Kasprzaka 44/52, 01-224 Warsaw, Poland
| | - Julia Kuczak
- Institute of Physical Chemistry, Polish Academy of Sciences, ul. Kasprzaka 44/52, 01-224 Warsaw, Poland
| | - Jan Guzowski
- Institute of Physical Chemistry, Polish Academy of Sciences, ul. Kasprzaka 44/52, 01-224 Warsaw, Poland
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11
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Sahin MA, Werner H, Udani S, Di Carlo D, Destgeer G. Flow lithography for structured microparticles: fundamentals, methods and applications. LAB ON A CHIP 2022; 22:4007-4042. [PMID: 35920614 DOI: 10.1039/d2lc00421f] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Structured microparticles, with unique shapes, customizable sizes, multiple materials, and spatially-defined chemistries, are leading the way for emerging 'lab on a particle' technologies. These microparticles with engineered designs find applications in multiplexed diagnostics, drug delivery, single-cell secretion assays, single-molecule detection assays, high throughput cytometry, micro-robotics, self-assembly, and tissue engineering. In this article we review state-of-the-art particle manufacturing technologies based on flow-assisted photolithography performed inside microfluidic channels. Important physicochemical concepts are discussed to provide a basis for understanding the fabrication technologies. These photolithography technologies are compared based on the structural as well as compositional complexity of the fabricated particles. Particles are categorized, from 1D to 3D particles, based on the number of dimensions that can be independently controlled during the fabrication process. After discussing the advantages of the individual techniques, important applications of the fabricated particles are reviewed. Lastly, a future perspective is provided with potential directions to improve the throughput of particle fabrication, realize new particle shapes, measure particles in an automated manner, and adopt the 'lab on a particle' technologies to other areas of research.
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Affiliation(s)
- Mehmet Akif Sahin
- Control and Manipulation of Microscale Living Objects, Central Institute for Translational Cancer Research (TranslaTUM), Department of Electrical and Computer Engineering, Technical University of Munich, Einsteinstraße 25, Munich 81675, Germany.
| | - Helen Werner
- Control and Manipulation of Microscale Living Objects, Central Institute for Translational Cancer Research (TranslaTUM), Department of Electrical and Computer Engineering, Technical University of Munich, Einsteinstraße 25, Munich 81675, Germany.
| | - Shreya Udani
- Department of Bioengineering, University of California, Los Angeles, California 90095, USA.
| | - Dino Di Carlo
- Department of Bioengineering, University of California, Los Angeles, California 90095, USA.
- Department of Mechanical and Aerospace Engineering, California NanoSystems Institute and Jonsson Comprehensive Cancer Center, University of California, Los Angeles, California 90095, USA
| | - Ghulam Destgeer
- Control and Manipulation of Microscale Living Objects, Central Institute for Translational Cancer Research (TranslaTUM), Department of Electrical and Computer Engineering, Technical University of Munich, Einsteinstraße 25, Munich 81675, Germany.
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12
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Ou BS, Saouaf OM, Baillet J, Appel EA. Sustained delivery approaches to improving adaptive immune responses. Adv Drug Deliv Rev 2022; 187:114401. [PMID: 35750115 DOI: 10.1016/j.addr.2022.114401] [Citation(s) in RCA: 32] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2022] [Revised: 06/14/2022] [Accepted: 06/17/2022] [Indexed: 11/17/2022]
Abstract
The immune system is one of the most important, complex biological networks regulating and protecting human health. Its precise modulation can prevent deadly infections and fight cancer. Accordingly, prophylactic vaccines and cancer immunotherapies are some of the most powerful technologies to protect against potential dangers through training of the immune system. Upon immunization, activation and maturation of B and T cells of the adaptive immune system are necessary for development of proper humoral and cellular protection. Yet, the exquisite organization of the immune system requires spatiotemporal control over the exposure of immunomodulatory signals. For example, while the human immune system has evolved to develop immunity to natural pathogenic infections that often last for weeks, current prophylactic vaccination technologies only expose the immune system to immunomodulatory signals for hours to days. It has become clear that leveraging sustained release technologies to prolong immunogen and adjuvant exposure can increase the potency, durability, and quality of adaptive immune responses. Over the past several years, tremendous breakthroughs have been made in the design of novel biomaterials such as nanoparticles, microparticles, hydrogels, and microneedles that can precisely control and the presentation of immunomodulatory signals to the immune system. In this review, we discuss relevant sustained release strategies and their corresponding benefits to cellular and humoral responses.
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Affiliation(s)
- Ben S Ou
- Department of Bioengineering, Stanford University, Stanford 94305, USA
| | - Olivia M Saouaf
- Department of Materials Science & Engineering, Stanford University, Stanford 94305, USA
| | - Julie Baillet
- Department of Materials Science & Engineering, Stanford University, Stanford 94305, USA; University of Bordeaux, CNRS, Bordeaux INP, LCPO, UMR 5629, Pessac 33600, France
| | - Eric A Appel
- Department of Bioengineering, Stanford University, Stanford 94305, USA; Department of Materials Science & Engineering, Stanford University, Stanford 94305, USA; Department of Pediatrics (Endocrinology), Stanford University, Stanford 94305, USA; ChEM-H Institute, Stanford University, Stanford CA 94305, USA; Woods Institute for the Environment, Stanford University, Stanford, CA 94305, USA.
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13
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Kim JW, Han SH, Choi YH, Hamonangan WM, Oh Y, Kim SH. Recent advances in the microfluidic production of functional microcapsules by multiple-emulsion templating. LAB ON A CHIP 2022; 22:2259-2291. [PMID: 35608122 DOI: 10.1039/d2lc00196a] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Multiple-emulsion drops serve as versatile templates to design functional microcapsules due to their core-shell geometry and multiple compartments. Microfluidics has been used for the elaborate production of multiple-emulsion drops with a controlled composition, order, and dimensions, elevating the value of multiple-emulsion templates. Moreover, recent advances in the microfluidic control of the emulsification and parallelization of drop-making junctions significantly enhance the production throughput for practical use. Metastable multiple-emulsion drops are converted into stable microcapsules through the solidification of selected phases, among which solid shells are designed to function in a programmed manner. Functional microcapsules are used for the storage and release of active materials as drug carriers. Beyond their conventional uses, microcapsules can serve as microcompartments responsible for transmembrane communication, which is promising for their application in advanced microreactors, artificial cells, and microsensors. Given that post-processing provides additional control over the composition and construction of multiple-emulsion drops, they are excellent confining geometries to study the self-assembly of colloids and liquid crystals and produce miniaturized photonic devices. This review article presents the recent progress and current state of the art in the microfluidic production of multiple-emulsion drops, functionalization of solid shells, and applications of microcapsules.
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Affiliation(s)
- Ji-Won Kim
- Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea.
| | - Sang Hoon Han
- Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea.
| | - Ye Hun Choi
- Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea.
| | - Wahyu Martumpal Hamonangan
- Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea.
| | - Yoonjin Oh
- Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea.
| | - Shin-Hyun Kim
- Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea.
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14
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LeValley PJ, Parsons AL, Sutherland BP, Kiick KL, Oakey JS, Kloxin AM. Microgels Formed by Spontaneous Click Chemistries Utilizing Microfluidic Flow Focusing for Cargo Release in Response to Endogenous or Exogenous Stimuli. Pharmaceutics 2022; 14:1062. [PMID: 35631649 PMCID: PMC9145542 DOI: 10.3390/pharmaceutics14051062] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2022] [Revised: 05/04/2022] [Accepted: 05/09/2022] [Indexed: 02/05/2023] Open
Abstract
Protein therapeutics have become increasingly popular for the treatment of a variety of diseases owing to their specificity to targets of interest. However, challenges associated with them have limited their use for a range of ailments, including the limited options available for local controlled delivery. To address this challenge, degradable hydrogel microparticles, or microgels, loaded with model biocargoes were created with tunable release profiles or triggered burst release using chemistries responsive to endogenous or exogeneous stimuli, respectively. Specifically, microfluidic flow-focusing was utilized to form homogenous microgels with different spontaneous click chemistries that afforded degradation either in response to redox environments for sustained cargo release or light for on-demand cargo release. The resulting microgels were an appropriate size to remain localized within tissues upon injection and were easily passed through a needle relevant for injection, providing means for localized delivery. Release of a model biopolymer was observed over the course of several weeks for redox-responsive formulations or triggered for immediate release from the light-responsive formulation. Overall, we demonstrate the ability of microgels to be formulated with different materials chemistries to achieve various therapeutic release modalities, providing new tools for creation of more complex protein release profiles to improve therapeutic regimens.
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Affiliation(s)
- Paige J. LeValley
- Chemical and Biomolecular Engineering, University of Delaware, Newark, DE 19716, USA; (P.J.L.); (B.P.S.)
| | - Amanda L. Parsons
- Chemical Engineering, University of Wyoming, Laramie, WY 82071, USA;
| | - Bryan P. Sutherland
- Chemical and Biomolecular Engineering, University of Delaware, Newark, DE 19716, USA; (P.J.L.); (B.P.S.)
| | - Kristi L. Kiick
- Materials Science and Engineering, University of Delaware, Newark, DE 19716, USA;
- Biomedical Engineering, University of Delaware, Newark, DE 19716, USA
| | - John S. Oakey
- Chemical Engineering, University of Wyoming, Laramie, WY 82071, USA;
| | - April M. Kloxin
- Chemical and Biomolecular Engineering, University of Delaware, Newark, DE 19716, USA; (P.J.L.); (B.P.S.)
- Materials Science and Engineering, University of Delaware, Newark, DE 19716, USA;
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15
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Díez-Pascual AM, Rahdar A. LbL Nano-Assemblies: A Versatile Tool for Biomedical and Healthcare Applications. NANOMATERIALS (BASEL, SWITZERLAND) 2022; 12:949. [PMID: 35335762 PMCID: PMC8954003 DOI: 10.3390/nano12060949] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/10/2022] [Revised: 03/02/2022] [Accepted: 03/10/2022] [Indexed: 02/04/2023]
Abstract
Polyelectrolytes (PEs) have been the aim of many research studies over the past years. PE films are prepared by the simple and versatile layer-by-layer (LbL) approach using alternating assemblies of polymer pairs involving a polyanion and a polycation. The adsorption of the alternating PE multiple layers is driven by different forces (i.e., electrostatic interactions, H-bonding, charge transfer interactions, hydrophobic forces, etc.), which enable an accurate control over the physical properties of the film (i.e., thickness at the nanoscale and morphology). These PE nano-assemblies have a wide range of biomedical and healthcare applications, including drug delivery, protein delivery, tissue engineering, wound healing, and so forth. This review provides a concise overview of the most outstanding research on the design and fabrication of PE nanofilms. Their nanostructures, molecular interactions with biomolecules, and applications in the biomedical field are briefly discussed. Finally, the perspectives of further research directions in the development of LbL nano-assemblies for healthcare and medical applications are highlighted.
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Affiliation(s)
- Ana M. Díez-Pascual
- Universidad de Alcalá, Facultad de Ciencias, Departamento de Química Analítica, Química Física e Ingeniería Química, Ctra. Madrid-Barcelona, Km. 33.6, 28805 Alcalá de Henares, Madrid, Spain
| | - Abbas Rahdar
- Department of Physics, Faculty of Science, University of Zabol, Zabol 538-98615, Iran;
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16
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Kittel Y, Kuehne AJC, De Laporte L. Translating Therapeutic Microgels into Clinical Applications. Adv Healthc Mater 2022; 11:e2101989. [PMID: 34826201 DOI: 10.1002/adhm.202101989] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2021] [Revised: 11/17/2021] [Indexed: 12/14/2022]
Abstract
Microgels are crosslinked, water-swollen networks with a 10 nm to 100 µm diameter and can be modified chemically or biologically to render them biocompatible for advanced clinical applications. Depending on their intended use, microgels require different mechanical and structural properties, which can be engineered on demand by altering the biochemical composition, crosslink density of the polymer network, and the fabrication method. Here, the fundamental aspects of microgel research and development, as well as their specific applications for theranostics and therapy in the clinic, are discussed. A detailed overview of microgel fabrication techniques with regards to their intended clinical application is presented, while focusing on how microgels can be employed as local drug delivery materials, scavengers, and contrast agents. Moreover, microgels can act as scaffolds for tissue engineering and regeneration application. Finally, an overview of microgels is given, which already made it into pre-clinical and clinical trials, while future challenges and chances are discussed. This review presents an instructive guideline for chemists, material scientists, and researchers in the biomedical field to introduce them to the fundamental physicochemical properties of microgels and guide them from fabrication methods via characterization techniques and functionalization of microgels toward specific applications in the clinic.
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Affiliation(s)
- Yonca Kittel
- DWI – Leibniz Institute for Interactive Materials Forckenbeckstrasse 50 52074 Aachen Germany
| | - Alexander J. C. Kuehne
- DWI – Leibniz Institute for Interactive Materials Forckenbeckstrasse 50 52074 Aachen Germany
- Institute of Organic and Macromolecular Chemistry Ulm University Albert‐Einstein‐Allee 11 89081 Ulm Germany
- Institute of Technical and Macromolecular Chemistry (ITMC) Polymeric Biomaterials RWTH University Aachen Worringerweg 2 52074 Aachen Germany
| | - Laura De Laporte
- DWI – Leibniz Institute for Interactive Materials Forckenbeckstrasse 50 52074 Aachen Germany
- Max Planck School‐Matter to Life (MtL) Jahnstraße 29 69120 Heidelberg Germany
- Advanced Materials for Biomedicine (AMB) Institute of Applied Medical Engineering (AME) Center for Biohybrid Medical Systems (CBMS) University Hospital RWTH 52074 Aachen Germany
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17
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Hauck N, Neuendorf TA, Männel MJ, Vogel L, Liu P, Stündel E, Zhang Y, Thiele J. Processing of fast-gelling hydrogel precursors in microfluidics by electrocoalescence of reactive species. SOFT MATTER 2021; 17:10312-10321. [PMID: 34664052 PMCID: PMC8612358 DOI: 10.1039/d1sm01176f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/11/2021] [Accepted: 10/12/2021] [Indexed: 06/13/2023]
Abstract
Microscopic hydrogels, also referred to as microgels, find broad application in life and materials science. A well-established technique for fabricating uniform microgels is droplet microfluidics. Here, optimal mixing of hydrogel precursor components is crucial to yield homogeneous microgels with respect to their morphology, mechanics, and distribution of functional moieties. However, when processing premixed polymer precursors that are highly reactive, fast or even instantaneous gelation inside fluid reservoirs or the microchannels of the flow cell commonly occurs, leading to an increase of fluid viscosity over time, and thus exacerbating the intrinsic control over fluid flow rates, droplet and microgel uniformity, which are key selling points of microfluidics in material design. To address these challenges, we utilize microflow cells with integrated electrodes, which enable fast addition and mixing of hydrogel precursors on demand by means of emulsion droplet coalescence. Here, two populations of surfactant-stabilized aqueous droplets - the first containing the material basis of the microgel, and the second containing another gel-forming component (e.g., a crosslinker) are formed at two consecutive microchannel junctions and merged via temporary thin-film instability. Our approach provides the ability to process such hydrogel systems that are otherwise challenging to process into uniform droplets and microgels by conventional droplet microfluidics. To demonstrate its versatility, we fabricate microgels with uniform shape and composition using fast hydrogelation via thiol-Michael addition reaction or non-covalent self-assembly. Furthermore, we elucidate the limitations of electrocoalescence of reactive hydrogel precursors by processing sodium alginate, crosslinked by calcium-induced ionic interactions. For this instantaneous type of hydrogelation, electrocoalescence of alginate and calcium ions does not result in the formation of morphologically isotropic microgels. Instead, it enables the creation of anisotropic microgel morphologies with tunable shape, which have previously only been achieved by selective crosslinking of elaborate higher-order emulsions or by aqueous two-phase systems as microgel templates.
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Affiliation(s)
- Nicolas Hauck
- Leibniz-Institut für Polymerforschung Dresden e.V., Hohe Str. 6, 01069 Dresden, Germany.
| | - Talika A Neuendorf
- Leibniz-Institut für Polymerforschung Dresden e.V., Hohe Str. 6, 01069 Dresden, Germany.
| | - Max J Männel
- Leibniz-Institut für Polymerforschung Dresden e.V., Hohe Str. 6, 01069 Dresden, Germany.
| | - Lucas Vogel
- Leibniz-Institut für Polymerforschung Dresden e.V., Hohe Str. 6, 01069 Dresden, Germany.
| | - Ping Liu
- B CUBE Center for Molecular Bioengineering, Technische Universität Dresden, Tatzberg 41, 01307 Dresden, Germany
| | - Enno Stündel
- Leibniz-Institut für Polymerforschung Dresden e.V., Hohe Str. 6, 01069 Dresden, Germany.
| | - Yixin Zhang
- B CUBE Center for Molecular Bioengineering, Technische Universität Dresden, Tatzberg 41, 01307 Dresden, Germany
- Cluster of Excellence Physics of Life, TU Dresden, Dresden, Germany
| | - Julian Thiele
- Leibniz-Institut für Polymerforschung Dresden e.V., Hohe Str. 6, 01069 Dresden, Germany.
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18
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Sharma A, Jung SH, Lomadze N, Pich A, Santer S, Bekir M. Adsorption Kinetics of a Photosensitive Surfactant Inside Microgels. Macromolecules 2021. [DOI: 10.1021/acs.macromol.1c01994] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Anjali Sharma
- Institute of Physics and Astronomy, University of Potsdam, 14476 Potsdam, Germany
| | - Se-Hyeong Jung
- DWI-Leibniz Institute for Interactive Materials e.V., 52074 Aachen, Germany
- Functional and Interactive Polymers, Institute of Technical and Macromolecular Chemistry, RWTH Aachen University, 52074 Aachen, Germany
| | - Nino Lomadze
- Institute of Physics and Astronomy, University of Potsdam, 14476 Potsdam, Germany
| | - Andrij Pich
- DWI-Leibniz Institute for Interactive Materials e.V., 52074 Aachen, Germany
- Functional and Interactive Polymers, Institute of Technical and Macromolecular Chemistry, RWTH Aachen University, 52074 Aachen, Germany
- Aachen Maastricht Institute for Biobased Materials (AMIBM), Maastricht University, 6167 RD Geleen, The Netherlands
| | - Svetlana Santer
- Institute of Physics and Astronomy, University of Potsdam, 14476 Potsdam, Germany
| | - Marek Bekir
- Institute of Physics and Astronomy, University of Potsdam, 14476 Potsdam, Germany
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19
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Sheth S, Stealey S, Morgan NY, Zustiak SP. Microfluidic Chip Device for In Situ Mixing and Fabrication of Hydrogel Microspheres via Michael-Type Addition. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2021; 37:11793-11803. [PMID: 34597052 PMCID: PMC9447845 DOI: 10.1021/acs.langmuir.1c01739] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Hydrogel microspheres are sought for a variety of biomedical applications, including therapeutic and cellular delivery, sensors, and lubricants. Robust fabrication of hydrogel microspheres with uniform sizes and properties can be achieved using microfluidic systems that rely on droplet formation and subsequent gelation to form microspheres. Such systems work well when gelation is initiated after droplet formation but are not practical for timed gelation systems where gelation is initiated prior to droplet formation; premature gelation can lead to device blockage, variable microsphere diameter due to viscosity changes in the precursor solution, and limited numbers of microspheres produced in a single run. To enable microfluidic fabrication of microspheres from timed gelation hydrogel systems, an in situ mixing region is needed so that various hydrogel precursor components can be added separately. Here, we designed and evaluated three mixing devices for their effectiveness at mixing hydrogel precursor solutions prior to droplet formation and subsequent gelation. The serpentine geometry was found to be the most effective and was further improved with the inclusion of a pillar array to increase agitation. The optimized device was shown to fully mix precursor solutions and enable the fabrication of monodisperse polyethylene glycol microspheres, offering great potential for use with timed gelation hydrogel systems.
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Affiliation(s)
- Saahil Sheth
- Department of Biomedical Engineering, Saint Louis University, St. Louis, MO, USA 63103
| | - Samuel Stealey
- Department of Biomedical Engineering, Saint Louis University, St. Louis, MO, USA 63103
| | - Nicole Y. Morgan
- Biomedical Engineering and Physical Science Shared Resource, National Institute of Biomedical Imaging and Bioengineering, National Institutes of Health, Bethesda, Maryland, USA 20814
| | - Silviya P. Zustiak
- Department of Biomedical Engineering, Saint Louis University, St. Louis, MO, USA 63103
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20
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Dimitriou P, Li J, Tornillo G, McCloy T, Barrow D. Droplet Microfluidics for Tumor Drug-Related Studies and Programmable Artificial Cells. GLOBAL CHALLENGES (HOBOKEN, NJ) 2021; 5:2000123. [PMID: 34267927 PMCID: PMC8272004 DOI: 10.1002/gch2.202000123] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/02/2020] [Revised: 03/19/2021] [Indexed: 05/11/2023]
Abstract
Anticancer drug development is a crucial step toward cancer treatment, that requires realistic predictions of malignant tissue development and sophisticated drug delivery. Tumors often acquire drug resistance and drug efficacy, hence cannot be accurately predicted in 2D tumor cell cultures. On the other hand, 3D cultures, including multicellular tumor spheroids (MCTSs), mimic the in vivo cellular arrangement and provide robust platforms for drug testing when grown in hydrogels with characteristics similar to the living body. Microparticles and liposomes are considered smart drug delivery vehicles, are able to target cancerous tissue, and can release entrapped drugs on demand. Microfluidics serve as a high-throughput tool for reproducible, flexible, and automated production of droplet-based microscale constructs, tailored to the desired final application. In this review, it is described how natural hydrogels in combination with droplet microfluidics can generate MCTSs, and the use of microfluidics to produce tumor targeting microparticles and liposomes. One of the highlights of the review documents the use of the bottom-up construction methodologies of synthetic biology for the formation of artificial cellular assemblies, which may additionally incorporate both target cancer cells and prospective drug candidates, as an integrated "droplet incubator" drug assay platform.
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Affiliation(s)
- Pantelitsa Dimitriou
- Applied Microfluidic LaboratorySchool of EngineeringCardiff UniversityCardiffCF24 3AAUK
| | - Jin Li
- Applied Microfluidic LaboratorySchool of EngineeringCardiff UniversityCardiffCF24 3AAUK
| | - Giusy Tornillo
- Hadyn Ellis BuildingCardiff UniversityMaindy RoadCardiffCF24 4HQUK
| | - Thomas McCloy
- Applied Microfluidic LaboratorySchool of EngineeringCardiff UniversityCardiffCF24 3AAUK
| | - David Barrow
- Applied Microfluidic LaboratorySchool of EngineeringCardiff UniversityCardiffCF24 3AAUK
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21
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Crosslinking Strategies for the Microfluidic Production of Microgels. Molecules 2021; 26:molecules26123752. [PMID: 34202959 PMCID: PMC8234156 DOI: 10.3390/molecules26123752] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2021] [Revised: 06/17/2021] [Accepted: 06/18/2021] [Indexed: 02/03/2023] Open
Abstract
This article provides a systematic review of the crosslinking strategies used to produce microgel particles in microfluidic chips. Various ionic crosslinking methods for the gelation of charged polymers are discussed, including external gelation via crosslinkers dissolved or dispersed in the oil phase; internal gelation methods using crosslinkers added to the dispersed phase in their non-active forms, such as chelating agents, photo-acid generators, sparingly soluble or slowly hydrolyzing compounds, and methods involving competitive ligand exchange; rapid mixing of polymer and crosslinking streams; and merging polymer and crosslinker droplets. Covalent crosslinking methods using enzymatic oxidation of modified biopolymers, photo-polymerization of crosslinkable monomers or polymers, and thiol-ene “click” reactions are also discussed, as well as methods based on the sol−gel transitions of stimuli responsive polymers triggered by pH or temperature change. In addition to homogeneous microgel particles, the production of structurally heterogeneous particles such as composite hydrogel particles entrapping droplet interface bilayers, core−shell particles, organoids, and Janus particles are also discussed. Microfluidics offers the ability to precisely tune the chemical composition, size, shape, surface morphology, and internal structure of microgels by bringing multiple fluid streams in contact in a highly controlled fashion using versatile channel geometries and flow configurations, and allowing for controlled crosslinking.
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22
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Babu S, Albertino F, Omidinia Anarkoli A, De Laporte L. Controlling Structure with Injectable Biomaterials to Better Mimic Tissue Heterogeneity and Anisotropy. Adv Healthc Mater 2021; 10:e2002221. [PMID: 33951341 PMCID: PMC11469279 DOI: 10.1002/adhm.202002221] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2020] [Revised: 03/17/2021] [Indexed: 12/15/2022]
Abstract
Tissue regeneration of sensitive tissues calls for injectable scaffolds, which are minimally invasive and offer minimal damage to the native tissues. However, most of these systems are inherently isotropic and do not mimic the complex hierarchically ordered nature of the native extracellular matrices. This review focuses on the different approaches developed in the past decade to bring in some form of anisotropy to the conventional injectable tissue regenerative matrices. These approaches include introduction of macroporosity, in vivo pattering to present biomolecules in a spatially and temporally controlled manner, availability of aligned domains by means of self-assembly or oriented injectable components, and in vivo bioprinting to obtain structures with features of high resolution that resembles native tissues. Toward the end of the review, different techniques to produce building blocks for the fabrication of heterogeneous injectable scaffolds are discussed. The advantages and shortcomings of each approach are discussed in detail with ideas to improve the functionality and versatility of the building blocks.
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Affiliation(s)
- Susan Babu
- Institute of Technical and Macromolecular Chemistry (ITMC)Polymeric BiomaterialsRWTH University AachenWorringerweg 2Aachen52074Germany
- DWI‐Leibniz Institute for Interactive MaterialsForckenbeckstrasse 50Aachen52074Germany
- Max Planck School‐Matter to Life (MtL)Jahnstrasse 29Heidelberg69120Germany
| | - Filippo Albertino
- DWI‐Leibniz Institute for Interactive MaterialsForckenbeckstrasse 50Aachen52074Germany
| | | | - Laura De Laporte
- Institute of Technical and Macromolecular Chemistry (ITMC)Polymeric BiomaterialsRWTH University AachenWorringerweg 2Aachen52074Germany
- DWI‐Leibniz Institute for Interactive MaterialsForckenbeckstrasse 50Aachen52074Germany
- Max Planck School‐Matter to Life (MtL)Jahnstrasse 29Heidelberg69120Germany
- Advanced Materials for Biomedicine (AMB)Institute of Applied Medical Engineering (AME)Center for Biohybrid Medical Systems (CMBS)University Hospital RWTH AachenForckenbeckstrasse 55Aachen52074Germany
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23
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Steinacher M, Cont A, Du H, Persat A, Amstad E. Monodisperse Selectively Permeable Hydrogel Capsules Made from Single Emulsion Drops. ACS APPLIED MATERIALS & INTERFACES 2021; 13:15601-15609. [PMID: 33764041 DOI: 10.1021/acsami.1c00230] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Capsules are often used to protect chemical and biological entities from the environment, to control the timing and location of their release, or to facilitate the collection of waste. Their performance depends on the thickness and composition of their shells, which can be closely controlled if capsules are made from double emulsion drops that are produced with microfluidics. However, the fabrication of such double emulsions is delicate, limiting throughput and increasing costs. Here, a fast, scalable method to produce monodisperse microcapsules possessing mechanically robust, thin, semipermeable hydrogel shells from single emulsion drops is introduced. This is achieved by selectively polymerizing reagents in close proximity to the drop surface to form a biocompatible 1.6 μm-thick hydrogel shell that encompasses a liquid core. The size-selective permeability of the shell enables the growth of living yeast and bacteria in their cores. Moreover, if capsules are loaded with adsorbents, they can repetitively remove waste products from water. The simplicity and robustness of the capsule fabrication makes the process scalable and cost effective. It has thus the potential to extend the use of calibrated capsules possessing well-defined dimensions to cost sensitive fields, including food, waste water treatment, or oil recovery.
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Affiliation(s)
- Mathias Steinacher
- Soft Materials Laboratory, Institute of Materials, École Polytechnique Fédérale de Lausanne (EPFL), Lausanne 1015, Switzerland
| | - Alice Cont
- Institute of Bioengineering and Global Health Institute, School of Life Sciences, École Polytechnique Fédérale de Lausanne (EPFL), Lausanne 1015, Switzerland
| | - Huachuan Du
- Soft Materials Laboratory, Institute of Materials, École Polytechnique Fédérale de Lausanne (EPFL), Lausanne 1015, Switzerland
| | - Alexandre Persat
- Institute of Bioengineering and Global Health Institute, School of Life Sciences, École Polytechnique Fédérale de Lausanne (EPFL), Lausanne 1015, Switzerland
| | - Esther Amstad
- Soft Materials Laboratory, Institute of Materials, École Polytechnique Fédérale de Lausanne (EPFL), Lausanne 1015, Switzerland
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24
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Liu EY, Choi Y, Yi H, Choi CH. Triple Emulsion-Based Rapid Microfluidic Production of Core-Shell Hydrogel Microspheres for Programmable Biomolecular Conjugation. ACS APPLIED MATERIALS & INTERFACES 2021; 13:11579-11587. [PMID: 33651584 DOI: 10.1021/acsami.0c20081] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
We report a simple and rapid microfluidic approach to produce core-shell hydrogel microspheres in a single step. We exploit triple emulsion drops with sacrificial oil layers that separate two prepolymer phases, forming poly(ethylene glycol)-based core-shell microspheres via photopolymerization followed by spontaneous removal of the oil layer. Our technique enables the production of monodisperse core-shell microspheres with varying dimensions of each compartment by independently and precisely controlled flow rates. This leads to stable and uniform incorporation of functional moieties in the core compartment with negligible cross-contamination into the shell layer. Selective conjugation of biomolecules is enabled through a rapid bioorthogonal reaction with functional groups in the core compartment with minimal non-specific adsorption. Finally, in-depth protein conjugation kinetics studies using microspheres with varying shell porosities highlight the capability to provide tunable size-selective diffusion barriers by simple tuning of prepolymer compositions for the shell layer. Combined, these results illustrate a significant step forward for programmable high-throughput fabrication of multifunctional hydrogel microspheres, which possess substantial potential in a large array of biomedical and biochemical applications.
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Affiliation(s)
- Eric Y Liu
- Department of Chemical and Biological Engineering, Tufts University, Medford, Massachusetts 02155, United States
| | - Yoon Choi
- Division of Cosmetic Science and Technology, Daegu Haany University, 1 Haanydaero, Gyeongsan-si, Gyeongsangbuk-do 38610, Republic of Korea
| | - Hyunmin Yi
- Department of Chemical and Biological Engineering, Tufts University, Medford, Massachusetts 02155, United States
| | - Chang-Hyung Choi
- Division of Cosmetic Science and Technology, Daegu Haany University, 1 Haanydaero, Gyeongsan-si, Gyeongsangbuk-do 38610, Republic of Korea
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25
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Nothdurft K, Müller DH, Mürtz SD, Meyer AA, Guerzoni LPB, Jans A, Kühne AJC, De Laporte L, Brands T, Bardow A, Richtering W. Is the Microgel Collapse a Two-Step Process? Exploiting Cononsolvency to Probe the Collapse Dynamics of Poly- N-isopropylacrylamide (pNIPAM). J Phys Chem B 2021; 125:1503-1512. [PMID: 33503378 DOI: 10.1021/acs.jpcb.0c10430] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Many applications of responsive microgels rely on the fast adaptation of the polymer network. However, the underlying dynamics of the de-/swelling process of the gels have not been fully understood. In the present work, we focus on the collapse kinetics of poly-N-isopropylacrylamide (pNIPAM) microgels due to cononsolvency. Cononsolvency means that either of the pure solvents, e.g., pure water or pure methanol, act as a so-called good solvent, leading to a swollen state of the polymer network. However, in mixtures of water and methanol, the previously swollen network undergoes a drastic volume loss. To further elucidate the cononsolvency transition, pNIPAM microgels with diameters between 20 and 110 μm were synthesized by microfluidics. To follow the dynamics, pure water was suddenly exchanged with an unfavorable mixture of 20 mol% methanol (solvent-jump) within a microfluidic channel. The dynamic response of the microgels was investigated by optical and fluorescence microscopy and Raman microspectroscopy. The experimental data provide unique and detailed insight into the size-dependent kinetics of the volume phase transition due to cononsolvency. The change in the microgel's diameter over time points to a two-step process of the microgel collapse with a biexponential behavior. Furthermore, the dependence between the two time constants from this biexponential behavior and the microgel's diameter in the collapsed state deviates from the square-power law proposed by Tanaka and Fillmore [ J. Chem. Phys. 1979, 70, 1214-1218]. The deviation is discussed considering the adhesion-induced deformation of the gels and the physical processes underlying the collapse.
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Affiliation(s)
- Katja Nothdurft
- Institute of Physical Chemistry, RWTH Aachen University, Landoltweg 2, 52056 Aachen, Germany
| | - David H Müller
- Institute of Technical Thermodynamics, RWTH Aachen University, Schinkelstr. 8, 52062 Aachen, Germany
| | - Sonja D Mürtz
- Institute of Physical Chemistry, RWTH Aachen University, Landoltweg 2, 52056 Aachen, Germany
| | - Anna A Meyer
- Institute of Physical Chemistry, RWTH Aachen University, Landoltweg 2, 52056 Aachen, Germany
| | - Luis P B Guerzoni
- DWI-Leibniz Institute for Interactive Materials, Forckenbeckstr. 50, 52074 Aachen, Germany
| | - Alexander Jans
- DWI-Leibniz Institute for Interactive Materials, Forckenbeckstr. 50, 52074 Aachen, Germany
| | - Alexander J C Kühne
- DWI-Leibniz Institute for Interactive Materials, Forckenbeckstr. 50, 52074 Aachen, Germany
| | - Laura De Laporte
- DWI-Leibniz Institute for Interactive Materials, Forckenbeckstr. 50, 52074 Aachen, Germany.,Institute of Technical and Macromolecular Chemistry, RWTH Aachen, Worringerweg 1-2, 52074 Aachen, Germany
| | - Thorsten Brands
- Institute of Technical Thermodynamics, RWTH Aachen University, Schinkelstr. 8, 52062 Aachen, Germany
| | - André Bardow
- Institute of Technical Thermodynamics, RWTH Aachen University, Schinkelstr. 8, 52062 Aachen, Germany.,Department of Mechanical and Process Engineering, ETH Zürich, Tannenstr. 3, 8092 Zürich, Switzerland
| | - Walter Richtering
- Institute of Physical Chemistry, RWTH Aachen University, Landoltweg 2, 52056 Aachen, Germany.,DWI-Leibniz Institute for Interactive Materials, Forckenbeckstr. 50, 52074 Aachen, Germany
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26
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Widener AE, Bhatta M, Angelini TE, Phelps EA. Guest-host interlinked PEG-MAL granular hydrogels as an engineered cellular microenvironment. Biomater Sci 2021; 9:2480-2493. [PMID: 33432940 DOI: 10.1039/d0bm01499k] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
We report the development of a polyethylene glycol (PEG) hydrogel scaffold that provides the advantages of conventional bulk PEG hydrogels for engineering cellular microenvironments and allows for rapid cell migration. PEG microgels were used to assemble a densely packed granular system with an intrinsic interstitium-like negative space. In this material, guest-host molecular interactions provide reversible non-covalent linkages between discrete PEG microgel particles to form a cohesive bulk material. In guest-host chemistry, different guest molecules reversibly and non-covalently interact with their cyclic host molecules. Two species of PEG microgels were made, each with one functional group at the end of the four arm PEG-MAL functionalized using thiol click chemistry. The first was functionalized with the host molecule β-cyclodextrin, a cyclic oligosaccharide of repeating d-glucose units, and the other functionalized with the guest molecule adamantane. These two species provide a reversible guest-host interaction between microgel particles when mixed, generating an interlinked network with a percolated interstitium. We showed that this granular configuration, unlike conventional bulk PEG hydrogels, enabled the rapid migration of THP-1 monocyte cells. The guest-host microgels also exhibited shear-thinning behavior, providing a unique advantage over current bulk PEG hydrogels.
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Affiliation(s)
- Adrienne E Widener
- J. Crayton Pruitt Family Department of Biomedical Engineering, University of Florida, Gainesville, FL, USA.
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27
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Bochenek S, McNamee CE, Kappl M, Butt HJ, Richtering W. Interactions between a responsive microgel monolayer and a rigid colloid: from soft to hard interfaces. Phys Chem Chem Phys 2021; 23:16754-16766. [PMID: 34319323 DOI: 10.1039/d1cp01703a] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Responsive poly-N-isopropylacrylamide-based microgels are commonly used as model colloids with soft repulsive interactions. It has been shown that the microgel-microgel interaction in solution can be easily adjusted by varying the environmental parameters, e.g., temperature, pH, or salt concentration. Furthermore, microgels readily adsorb to liquid-gas and liquid-liquid interfaces forming responsive foams and emulsions that can be broken on-demand. In this work, we explore the interactions between microgel monolayers at the air-water interface and a hard colloid in the water. Force-distance curves between the monolayer and a silica particle were measured with the Monolayer Particle Interaction Apparatus. The measurements were conducted at different temperatures and lateral compressions, i.e., different surface pressures. The force-distance approach curves display long-range repulsive forces below the volume phase transition temperature of the microgels. Temperature and lateral compression reduce the stiffness of the monolayer. The adhesion increases with temperature and decreases with a lateral compression of the monolayer. When compressed laterally, the interactions between the microgels are hardly affected by temperature, as the directly adsorbed microgel fractions are nearly insensitive to temperature. In contrast, our findings show that the temperature-dependent swelling of the microgel fractions in the aqueous phase strongly influences the interaction with the probe. This is explained by a change in the microgel monolayer from a soft to a hard repulsive interface.
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Affiliation(s)
- Steffen Bochenek
- Institute of Physical Chemistry, RWTH Aachen University, Landoltweg 2, 52074 Aachen, Germany
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28
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Jung F, Ksiazkiewicz A, Mhamdi A, Pich A, Mitsos A. Model-Based Optimization of Microgel Synthesis in the μm Size Range. Ind Eng Chem Res 2020. [DOI: 10.1021/acs.iecr.0c04286] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Falco Jung
- Aachener Verfahrenstechnik-Process Systems Engineering, RWTH Aachen University, 52074 Aachen, Germany
| | | | - Adel Mhamdi
- Aachener Verfahrenstechnik-Process Systems Engineering, RWTH Aachen University, 52074 Aachen, Germany
| | - Andrij Pich
- DWI Leibniz Institute for Interactive Materials e.V., 52074 Aachen, Germany
- Institute of Technical and Macromolecular Chemistry, RWTH Aachen University, 52074 Aachen, Germany
- JARA-SOFT, 52056 Aachen, Germany
- Aachen Maastricht Institute for Biobased Materials, Maastricht University, Brightlands Chemelot Campus, Urmonderbaan 22, 6167 RD Geleen, The Netherlands
| | - Alexander Mitsos
- Aachener Verfahrenstechnik-Process Systems Engineering, RWTH Aachen University, 52074 Aachen, Germany
- JARA-SOFT, 52056 Aachen, Germany
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29
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Gehlen DB, Jürgens N, Omidinia-Anarkoli A, Haraszti T, George J, Walther A, Ye H, De Laporte L. Granular Cellulose Nanofibril Hydrogel Scaffolds for 3D Cell Cultivation. Macromol Rapid Commun 2020; 41:e2000191. [PMID: 32783361 DOI: 10.1002/marc.202000191] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2020] [Revised: 07/06/2020] [Indexed: 12/15/2022]
Abstract
The replacement of diseased and damaged organs remains an challenge in modern medicine. However, through the use of tissue engineering techniques, it may soon be possible to (re)generate tissues and organs using artificial scaffolds. For example, hydrogel networks made from hydrophilic precursor solutions can replicate many properties found in the natural extracellular matrix (ECM) but often lack the dynamic nature of the ECM, as many covalently crosslinked hydrogels possess elastic and static networks with nanoscale pores hindering cell migration without being degradable. To overcome this, macroporous colloidal hydrogels can be prepared to facilitate cell infiltration. Here, an easy method is presented to fabricate granular cellulose nanofibril hydrogel (CNF) scaffolds as porous networks for 3D cell cultivation. CNF is an abundant natural and highly biocompatible material that supports cell adhesion. Granular CNF scaffolds are generated by pre-crosslinking CNF using calcium and subsequently pressing the gel through micrometer-sized nylon meshes. The granular solution is mixed with fibroblasts and crosslinked with cell culture medium. The obtained granular CNF scaffold is significantly softer and enables well-distributed fibroblast growth. This cost-effective material combined with this efficient and facile fabrication technique allows for 3D cell cultivation in an upscalable manner.
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Affiliation(s)
- David B Gehlen
- DWI-Leibniz-Institute for Interactive Materials, Forckenbeckstr. 50, D-52074, Aachen, Germany.,Institute for Technical and Macromolecular Chemistry, RWTH Aachen University, Worringerweg 1-2, D-52074, Aachen, Germany
| | - Niklas Jürgens
- DWI-Leibniz-Institute for Interactive Materials, Forckenbeckstr. 50, D-52074, Aachen, Germany.,Institute for Technical and Macromolecular Chemistry, RWTH Aachen University, Worringerweg 1-2, D-52074, Aachen, Germany
| | - Abdolrahman Omidinia-Anarkoli
- DWI-Leibniz-Institute for Interactive Materials, Forckenbeckstr. 50, D-52074, Aachen, Germany.,Institute for Technical and Macromolecular Chemistry, RWTH Aachen University, Worringerweg 1-2, D-52074, Aachen, Germany
| | - Tamás Haraszti
- DWI-Leibniz-Institute for Interactive Materials, Forckenbeckstr. 50, D-52074, Aachen, Germany.,Institute for Technical and Macromolecular Chemistry, RWTH Aachen University, Worringerweg 1-2, D-52074, Aachen, Germany
| | - Julian George
- Institute of Biomedical Engineering, Department of Engineering Science, Old Road Campus Research Building, University of Oxford, Headington, OX3 7DQ, Oxford, UK
| | - Andreas Walther
- Freiburg Center for Interactive Materials and Bioinspired Technologies (FIT), University of Freiburg, Georges-Köhler-Allee 105, D-79110, Freiburg, Germany
| | - Hua Ye
- Institute of Biomedical Engineering, Department of Engineering Science, Old Road Campus Research Building, University of Oxford, Headington, OX3 7DQ, Oxford, UK
| | - Laura De Laporte
- DWI-Leibniz-Institute for Interactive Materials, Forckenbeckstr. 50, D-52074, Aachen, Germany.,Institute for Technical and Macromolecular Chemistry, RWTH Aachen University, Worringerweg 1-2, D-52074, Aachen, Germany.,Department of Advanced Materials for Biomedicine, Institute of Applied Medical Engineering, RWTH Aachen University, 52074, Aachen, Germany
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30
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Heida T, Otto O, Biedenweg D, Hauck N, Thiele J. Microfluidic Fabrication of Click Chemistry-Mediated Hyaluronic Acid Microgels: A Bottom-Up Material Guide to Tailor a Microgel's Physicochemical and Mechanical Properties. Polymers (Basel) 2020; 12:E1760. [PMID: 32781609 PMCID: PMC7464250 DOI: 10.3390/polym12081760] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2020] [Revised: 07/29/2020] [Accepted: 07/29/2020] [Indexed: 12/17/2022] Open
Abstract
The demand for tailored, micrometer-scaled biomaterials in cell biology and (cell-free) biotechnology has led to the development of tunable microgel systems based on natural polymers, such as hyaluronic acid (HA). To precisely tailor their physicochemical and mechanical properties and thus to address the need for well-defined microgel systems, in this study, a bottom-up material guide is presented that highlights the synergy between highly selective bio-orthogonal click chemistry strategies and the versatility of a droplet microfluidics (MF)-assisted microgel design. By employing MF, microgels based on modified HA-derivates and homobifunctional poly(ethylene glycol) (PEG)-crosslinkers are prepared via three different types of click reaction: Diels-Alder [4 + 2] cycloaddition, strain-promoted azide-alkyne cycloaddition (SPAAC), and UV-initiated thiol-ene reaction. First, chemical modification strategies of HA are screened in-depth. Beyond the microfluidic processing of HA-derivates yielding monodisperse microgels, in an analytical study, we show that their physicochemical and mechanical properties-e.g., permeability, (thermo)stability, and elasticity-can be systematically adapted with respect to the type of click reaction and PEG-crosslinker concentration. In addition, we highlight the versatility of our HA-microgel design by preparing non-spherical microgels and introduce, for the first time, a selective, hetero-trifunctional HA-based microgel system with multiple binding sites. As a result, a holistic material guide is provided to tailor fundamental properties of HA-microgels for their potential application in cell biology and (cell-free) biotechnology.
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Affiliation(s)
- Thomas Heida
- Institute of Physical Chemistry and Polymer Physics, Leibniz-Institut für Polymerforschung Dresden e. V., 01069 Dresden, Germany; (T.H.); (N.H.)
| | - Oliver Otto
- Center for Innovation Competence: Humoral Immune Reactions in Cardiovascular Disorders, University of Greifswald, Fleischmannstr. 42, 17489 Greifswald, Germany;
- German Center for Cardiovascular Research e. V., University Medicine Greifswald, Fleischmannstr. 42, 17489 Greifswald, Germany
| | - Doreen Biedenweg
- Clinic for Internal Medicine B, University Medicine Greifswald, Fleischmannstr. 8, 17475 Greifswald, Germany;
| | - Nicolas Hauck
- Institute of Physical Chemistry and Polymer Physics, Leibniz-Institut für Polymerforschung Dresden e. V., 01069 Dresden, Germany; (T.H.); (N.H.)
| | - Julian Thiele
- Institute of Physical Chemistry and Polymer Physics, Leibniz-Institut für Polymerforschung Dresden e. V., 01069 Dresden, Germany; (T.H.); (N.H.)
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31
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Choi YH, Lee SS, Lee DM, Jeong HS, Kim SH. Composite Microgels Created by Complexation between Polyvinyl Alcohol and Graphene Oxide in Compressed Double-Emulsion Drops. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2020; 16:e1903812. [PMID: 31515955 DOI: 10.1002/smll.201903812] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/16/2019] [Revised: 08/21/2019] [Indexed: 05/22/2023]
Abstract
Microgels, microparticles made of hydrogels, show fast diffusion kinetics and high reconfigurability while maintaining the advantages of hydrogels, being useful for various applications. Here, presented is a new microfluidic strategy for producing polymer-graphene oxide (GO) composite microgels without chemical cues or a temperature swing for gelation. As a main component of microgels, polymers that are able to form hydrogen bonds, such as polyvinyl alcohol (PVA), are used. In the mixture of PVA and GO, GO is tethered by PVA through hydrogen bonding. When the mixture is rapidly concentrated in the core of double-emulsion drops by osmotic-pressure-driven water pumping, PVA-tethered GO sheets form a nematic phase with a planar alignment. In addition, the GO sheets are linked by additional hydrogen bonds, leading to a sol-gel transition. Therefore, the PVA-GO composite remains undissolved when it is directly exposed to water by oil-shell rupture. These composite microgels can be also produced using poly(ethylene oxide) or poly(acrylic acid), instead of PVA. In addition, the microgels can be functionalized by incorporating other polymers in the presence of the hydrogel-forming polymers. It is shown that the multicomponent microgels made from a mixture of polyacrylamide, PVA, and GO show an excellent adsorption capacity for impurities.
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Affiliation(s)
- Ye Hun Choi
- Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea
| | - Sang Seok Lee
- Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea
- Functional Composite Materials Research Center, Institute of Advanced Composite Materials, Korea Institute of Science and Technology (KIST), Wanju-gun, Jeollabuk-do, 55324, Republic of Korea
| | - Dong-Myeong Lee
- Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea
- Functional Composite Materials Research Center, Institute of Advanced Composite Materials, Korea Institute of Science and Technology (KIST), Wanju-gun, Jeollabuk-do, 55324, Republic of Korea
| | - Hyeon Su Jeong
- Functional Composite Materials Research Center, Institute of Advanced Composite Materials, Korea Institute of Science and Technology (KIST), Wanju-gun, Jeollabuk-do, 55324, Republic of Korea
| | - Shin-Hyun Kim
- Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea
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32
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Neděla V, Tihlaříková E, Maxa J, Imrichová K, Bučko M, Gemeiner P. Simulation-based optimisation of thermodynamic conditions in the ESEM for dynamical in-situ study of spherical polyelectrolyte complex particles in their native state. Ultramicroscopy 2020; 211:112954. [PMID: 32018072 DOI: 10.1016/j.ultramic.2020.112954] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2019] [Revised: 01/23/2020] [Accepted: 01/26/2020] [Indexed: 11/18/2022]
Abstract
We present a complex analysis and optimisation of dynamic conditions in the environmental scanning electron microscope (ESEM) to allow in-situ observation of extremely delicate wet bio-polymeric spherical particles in their native state. According to the results of gas flow and heat transfer simulations, we were able to develop an improved procedure leading to thermodynamic equilibrium between the sample and chamber environment. To quantify and hence minimise the extent of any sample deformation during specimen chamber pumping, a strength-stress analysis is used. Monte Carlo simulations of beam-gas, -water, and -sample interactions describe beam scattering, absorbed energy, interaction volume and the emission of signal electrons in the ESEM. Finally, we discuss sample damage as a result of drying and the production of beam-induced free radicals. Based on all experimental and simulation results we introduce a Delicate Sample Observation Strategy for the ESEM. We show how this strategy can be applied to the characterization of polyelectrolyte complex spherical particles containing immobilized recombinant cells E. coli overexpressing cyclohexanone monooxygenase, used as a model biocatalyst. We present the first native-state electron microscopy images of the viscous core of a halved polyelectrolyte complex capsule containing living cells.
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Affiliation(s)
- Vilém Neděla
- Environmental electron microscopy group, Institute of Scientific Instruments of ASCR, Královopolská 147, 61264 Brno, Czech Republic.
| | - Eva Tihlaříková
- Environmental electron microscopy group, Institute of Scientific Instruments of ASCR, Královopolská 147, 61264 Brno, Czech Republic
| | - Jiří Maxa
- Environmental electron microscopy group, Institute of Scientific Instruments of ASCR, Královopolská 147, 61264 Brno, Czech Republic
| | - Kamila Imrichová
- Environmental electron microscopy group, Institute of Scientific Instruments of ASCR, Královopolská 147, 61264 Brno, Czech Republic
| | - Marek Bučko
- Institute of Chemistry, Centre for Glycomics, Slovak Academy of Sciences, Dúbravská cesta 9, 84538 Bratislava, Slovakia
| | - Peter Gemeiner
- Institute of Chemistry, Centre for Glycomics, Slovak Academy of Sciences, Dúbravská cesta 9, 84538 Bratislava, Slovakia
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33
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Huang X, Wang L, Zhao J, Liu C, Zhou F, Xu Z, Pei H. Fabrication and application of flexible rectangular microtubes. POLYM-PLAST TECH MAT 2020. [DOI: 10.1080/25740881.2019.1708104] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Affiliation(s)
- Xing Huang
- Institute of Process Equipment, College of Energy Engineering, Zhejiang University, Hangzhou, China
- John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, USA
| | - Lei Wang
- Institute of Process Equipment, College of Energy Engineering, Zhejiang University, Hangzhou, China
| | - Jianxiang Zhao
- Institute of Process Equipment, College of Energy Engineering, Zhejiang University, Hangzhou, China
| | - Cong Liu
- Institute of Process Equipment, College of Energy Engineering, Zhejiang University, Hangzhou, China
| | - Fanghao Zhou
- Institute of Process Equipment, College of Energy Engineering, Zhejiang University, Hangzhou, China
| | - Zhongbin Xu
- Institute of Process Equipment, College of Energy Engineering, Zhejiang University, Hangzhou, China
| | - Hao Pei
- John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, USA
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34
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Jans A, Lölsberg J, Omidinia-Anarkoli A, Viermann R, Möller M, De Laporte L, Wessling M, Kuehne AJC. High-Throughput Production of Micrometer Sized Double Emulsions and Microgel Capsules in Parallelized 3D Printed Microfluidic Devices. Polymers (Basel) 2019; 11:polym11111887. [PMID: 31731709 PMCID: PMC6918360 DOI: 10.3390/polym11111887] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2019] [Revised: 11/10/2019] [Accepted: 11/12/2019] [Indexed: 02/03/2023] Open
Abstract
Double emulsions are useful geometries as templates for core-shell particles, hollow sphere capsules, and for the production of biomedical delivery vehicles. In microfluidics, two approaches are currently being pursued for the preparation of microfluidic double emulsion devices. The first approach utilizes soft lithography, where many identical double-flow-focusing channel geometries are produced in a hydrophobic silicone matrix. This technique requires selective surface modification of the respective channel sections to facilitate alternating wetting conditions of the channel walls to obtain monodisperse double emulsion droplets. The second technique relies on tapered glass capillaries, which are coaxially aligned, so that double emulsions are produced after flow focusing of two co-flowing streams. This technique does not require surface modification of the capillaries, as only the continuous phase is in contact with the emulsifying orifice; however, these devices cannot be fabricated in a reproducible manner, which results in polydisperse double emulsion droplets, if these capillary devices were to be parallelized. Here, we present 3D printing as a means to generate four identical and parallelized capillary device architectures, which produce monodisperse double emulsions with droplet diameters in the range of 500 µm. We demonstrate high throughput synthesis of W/O/W and O/W/O double emulsions, without the need for time-consuming surface treatment of the 3D printed microfluidic device architecture. Finally, we show that we can apply this device platform to generate hollow sphere microgels.
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Affiliation(s)
- Alexander Jans
- DWI—Leibniz Institute for Interactive Materials, Forckenbeckstraße 50, 52076 Aachen, Germany; (A.J.); (J.L.); (A.O.-A.); (R.V.); (M.M.); (L.D.L.); (M.W.)
| | - Jonas Lölsberg
- DWI—Leibniz Institute for Interactive Materials, Forckenbeckstraße 50, 52076 Aachen, Germany; (A.J.); (J.L.); (A.O.-A.); (R.V.); (M.M.); (L.D.L.); (M.W.)
- AVT—Chemical Process Engineering, RWTH Aachen University, Forckenbeckstraße 51, 52074 Aachen, Germany
| | - Abdolrahman Omidinia-Anarkoli
- DWI—Leibniz Institute for Interactive Materials, Forckenbeckstraße 50, 52076 Aachen, Germany; (A.J.); (J.L.); (A.O.-A.); (R.V.); (M.M.); (L.D.L.); (M.W.)
| | - Robin Viermann
- DWI—Leibniz Institute for Interactive Materials, Forckenbeckstraße 50, 52076 Aachen, Germany; (A.J.); (J.L.); (A.O.-A.); (R.V.); (M.M.); (L.D.L.); (M.W.)
| | - Martin Möller
- DWI—Leibniz Institute for Interactive Materials, Forckenbeckstraße 50, 52076 Aachen, Germany; (A.J.); (J.L.); (A.O.-A.); (R.V.); (M.M.); (L.D.L.); (M.W.)
| | - Laura De Laporte
- DWI—Leibniz Institute for Interactive Materials, Forckenbeckstraße 50, 52076 Aachen, Germany; (A.J.); (J.L.); (A.O.-A.); (R.V.); (M.M.); (L.D.L.); (M.W.)
| | - Matthias Wessling
- DWI—Leibniz Institute for Interactive Materials, Forckenbeckstraße 50, 52076 Aachen, Germany; (A.J.); (J.L.); (A.O.-A.); (R.V.); (M.M.); (L.D.L.); (M.W.)
- AVT—Chemical Process Engineering, RWTH Aachen University, Forckenbeckstraße 51, 52074 Aachen, Germany
| | - Alexander J. C. Kuehne
- DWI—Leibniz Institute for Interactive Materials, Forckenbeckstraße 50, 52076 Aachen, Germany; (A.J.); (J.L.); (A.O.-A.); (R.V.); (M.M.); (L.D.L.); (M.W.)
- OC3—Institute of Organic and Macromolecular Chemistry, Ulm University, Albert-Einstein-Allee 11, 89081 Ulm, Germany
- Correspondence:
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35
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Nickel AC, Scotti A, Houston JE, Ito T, Crassous J, Pedersen JS, Richtering W. Anisotropic Hollow Microgels That Can Adapt Their Size, Shape, and Softness. NANO LETTERS 2019; 19:8161-8170. [PMID: 31613114 DOI: 10.1021/acs.nanolett.9b03507] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
The development of soft anisotropic building blocks is of great interest for various applications in soft matter. Furthermore, such systems would be important model systems for ordering phenomena in fundamental soft matter science. In this work, we address the challenge of creating hollow and anisotropically shaped thermoresponsive microgels, polymeric networks with a solvent filled cavity in their center that are swollen in a good solvent. Sacrificial elliptical hematite silica particles were utilized as a template for the synthesis of a cross-linked N-isopropylacrylamide (NIPAm) shell. By varying the amount of NIPAm, two anisotropic microgels were synthesized with either a thin or thick microgel shell. We characterized these precursor core-shell and the resulting hollow microgels using a combination of light, X-ray, and neutron scattering. New form factor models, accounting for the cavity, the polymer distribution and the anisotropy, have been developed for fitting the scattering data. With such models, we demonstrated the existence of the cavity and simultaneously the anisotropic character of the microgels. Furthermore, we show that the thickness of the shell has a major influence on the shape and the cavity dimension of the microgel after etching of the sacrificial core. Finally, the effect of temperature is investigated, showing that changes in size, softness, and aspect ratio are triggered by temperature.
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Affiliation(s)
- Anne C Nickel
- Institute of Physical Chemistry , RWTH Aachen University , 52056 Aachen , Germany
| | - Andrea Scotti
- Institute of Physical Chemistry , RWTH Aachen University , 52056 Aachen , Germany
| | - Judith E Houston
- Jülich Centre for Neutron Science (JCNS) at Heinz Maier-Leibnitz Zentrum (MLZ) , Forschungszentrum Jülich GmbH , Lichtenbergstrasse 1 , 85748 Garching , Germany
- European Spallation Source ERIC , Box 176, SE-221 00 Lund , Sweden
| | - Thiago Ito
- Physical Chemistry, Department of Chemistry , Lund University , SE-221 00 Lund , Sweden
| | - Jérôme Crassous
- Institute of Physical Chemistry , RWTH Aachen University , 52056 Aachen , Germany
| | - Jan Skov Pedersen
- Department of Chemistry and Interdisciplinary Nanoscience Centre (iNANO) , University of Aarhus , Gustav Wieds Vej 14 , DK-8000 Aarhus C , Denmark
| | - Walter Richtering
- Institute of Physical Chemistry , RWTH Aachen University , 52056 Aachen , Germany
- JARA-SOFT , 52056 Aachen , Germany
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36
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Gertig C, Kröger L, Fleitmann L, Scheffczyk J, Bardow A, Leonhard K. Rx-COSMO-CAMD: Computer-Aided Molecular Design of Reaction Solvents Based on Predictive Kinetics from Quantum Chemistry. Ind Eng Chem Res 2019. [DOI: 10.1021/acs.iecr.9b03232] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Christoph Gertig
- Institute of Technical Thermodynamics, RWTH Aachen University, Schinkelstraße 8, 52062 Aachen, Germany
| | - Leif Kröger
- Institute of Technical Thermodynamics, RWTH Aachen University, Schinkelstraße 8, 52062 Aachen, Germany
| | - Lorenz Fleitmann
- Institute of Technical Thermodynamics, RWTH Aachen University, Schinkelstraße 8, 52062 Aachen, Germany
| | - Jan Scheffczyk
- Institute of Technical Thermodynamics, RWTH Aachen University, Schinkelstraße 8, 52062 Aachen, Germany
| | - André Bardow
- Institute of Technical Thermodynamics, RWTH Aachen University, Schinkelstraße 8, 52062 Aachen, Germany
- Institute of Energy and Climate Research—Energy Systems Engineering (IEK-10), Forschungszentrum Jülich GmbH, Wilhelm-Johnen-Straße, 52425 Jülich, Germany
| | - Kai Leonhard
- Institute of Technical Thermodynamics, RWTH Aachen University, Schinkelstraße 8, 52062 Aachen, Germany
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Zou Y, Song J, You X, Yao J, Xie S, Jin M, Wang X, Yan Z, Zhou G, Shui L. Interfacial Complexation Induced Controllable Fabrication of Stable Polyelectrolyte Microcapsules Using All-Aqueous Droplet Microfluidics for Enzyme Release. ACS APPLIED MATERIALS & INTERFACES 2019; 11:21227-21238. [PMID: 31091079 DOI: 10.1021/acsami.9b02788] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Water-in-water (w/w) emulsions are particularly advantageous for biomedical-related applications, such as cell encapsulation, bioreactors, biocompatible storage, and processing of biomacromolecules. However, due to ultralow interfacial tension, generation and stabilization of uniform w/w droplets are challenging. In this work, we report a strategy of creating stable and size-controllable w/w droplets that can quickly form polyelectrolyte microcapsules (PEMCs) in a microfluidic device. A three-phase (inner, middle, outer) aqueous system was applied to create a stream of inner phase, which could be broken into droplets via a mechanical perturbation frequency, with size determined by the stream diameter and vibration frequency. The interfacial complexation is formed via electrostatic interaction of polycations of poly(diallyldimethylammoniumchloride) with polyanions of polystyrene sodium sulfate in the inner and outer phases. With addition of negatively charged silica nanoparticles, the stability, permeability, and mechanical strength of the PEMC shell could be well manipulated. Prepared PEMCs were verified by encapsulating fluorescein isothiocyanate-labeled dextran molecules and stimuli-triggered release by varying the pH value or osmotic pressure. A model enzyme, trypsin, was successfully encapsulated into PEMCs and released without impairing their catalytic activity. These results highlight its potential applications for efficient encapsulation, storage, delivery, and release of chemical, biological, pharmaceutical, and therapeutic agents.
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Affiliation(s)
| | - Jing Song
- Institute of Materials Research and Engineering, A*STAR (Agency for Science, Technology and Research) , 2 Fusionopolis Way, Innovis, #08-03 , 138634 Singapore
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38
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Scotti A, Denton AR, Brugnoni M, Houston JE, Schweins R, Potemkin II, Richtering W. Deswelling of Microgels in Crowded Suspensions Depends on Cross-Link Density and Architecture. Macromolecules 2019. [DOI: 10.1021/acs.macromol.9b00729] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Andrea Scotti
- Institute of Physical Chemistry, RWTH Aachen University, 52056 Aachen, Germany
| | - Alan R. Denton
- Department of Physics, North Dakota State University, Fargo, North Dakota 58108-6050 United States
| | - Monia Brugnoni
- Institute of Physical Chemistry, RWTH Aachen University, 52056 Aachen, Germany
| | - Judith E. Houston
- Jülich Centre for Neutron Science (JCNS) at Heinz Maier-Leibnitz Zentrum (MLZ), Forschungszentrum Jülich GmbH, Lichtenbergstr. 1, 85748 Garching, Germany
- European Spallation
Source ERIC, Box 176, SE-221 00 Lund, Sweden
| | - Ralf Schweins
- Institut Laue-Langevin
ILL DS/LSS, 71 Avenue des Martyrs, F-38000 Grenoble, France
| | - Igor I. Potemkin
- Physics Department, Lomonosov Moscow State University, 119991 Moscow, Russian Federation
- DWI - Leibniz
Institute
for Interactive Materials, Aachen 52056, Germany
- National Research South
Ural State University, Chelyabinsk 454080, Russian Federation
| | - Walter Richtering
- Institute of Physical Chemistry, RWTH Aachen University, 52056 Aachen, Germany
- JARA, Jülich Aachen
Research Alliance, 52056 Aachen, Germany
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39
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Karg M, Pich A, Hellweg T, Hoare T, Lyon LA, Crassous JJ, Suzuki D, Gumerov RA, Schneider S, Potemkin II, Richtering W. Nanogels and Microgels: From Model Colloids to Applications, Recent Developments, and Future Trends. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2019; 35:6231-6255. [PMID: 30998365 DOI: 10.1021/acs.langmuir.8b04304] [Citation(s) in RCA: 336] [Impact Index Per Article: 67.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
Nanogels and microgels are soft, deformable, and penetrable objects with an internal gel-like structure that is swollen by the dispersing solvent. Their softness and the potential to respond to external stimuli like temperature, pressure, pH, ionic strength, and different analytes make them interesting as soft model systems in fundamental research as well as for a broad range of applications, in particular in the field of biological applications. Recent tremendous developments in their synthesis open access to systems with complex architectures and compositions allowing for tailoring microgels with specific properties. At the same time state-of-the-art theoretical and simulation approaches offer deeper understanding of the behavior and structure of nano- and microgels under external influences and confinement at interfaces or at high volume fractions. Developments in the experimental analysis of nano- and microgels have become particularly important for structural investigations covering a broad range of length scales relevant to the internal structure, the overall size and shape, and interparticle interactions in concentrated samples. Here we provide an overview of the state-of-the-art, recent developments as well as emerging trends in the field of nano- and microgels. The following aspects build the focus of our discussion: tailoring (multi)functionality through synthesis; the role in biological and biomedical applications; the structure and properties as a model system, e.g., for densely packed arrangements in bulk and at interfaces; as well as the theory and computer simulation.
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Affiliation(s)
- Matthias Karg
- Physical Chemistry I , Heinrich-Heine-University Duesseldorf , 40204 Duesseldorf , Germany
| | - Andrij Pich
- DWI-Leibnitz-Institute for Interactive Materials e.V. , 52056 Aachen , Germany
- Functional and Interactive Polymers, Institute for Technical and Macromolecular Chemistry , RWTH Aachen University , 52056 Aachen , Germany
| | - Thomas Hellweg
- Physical and Biophysical Chemistry , Bielefeld University , 33615 Bielefeld , Germany
| | - Todd Hoare
- Department of Chemical Engineering , McMaster University , Hamilton , Ontario L8S 4L8 , Canada
| | - L Andrew Lyon
- Schmid College of Science and Technology , Chapman University , Orange , California 92866 , United States
| | - J J Crassous
- Institute of Physical Chemistry , RWTH Aachen University , 52056 Aachen , Germany
| | | | - Rustam A Gumerov
- DWI-Leibnitz-Institute for Interactive Materials e.V. , 52056 Aachen , Germany
- Physics Department , Lomonosov Moscow State University , Moscow 119991 , Russian Federation
| | - Stefanie Schneider
- Institute of Physical Chemistry , RWTH Aachen University , 52056 Aachen , Germany
| | - Igor I Potemkin
- DWI-Leibnitz-Institute for Interactive Materials e.V. , 52056 Aachen , Germany
- Physics Department , Lomonosov Moscow State University , Moscow 119991 , Russian Federation
- National Research South Ural State University , Chelyabinsk 454080 , Russian Federation
| | - Walter Richtering
- Institute of Physical Chemistry , RWTH Aachen University , 52056 Aachen , Germany
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40
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Guerzoni LPB, Rose JC, Gehlen DB, Jans A, Haraszti T, Wessling M, Kuehne AJC, De Laporte L. Cell Encapsulation in Soft, Anisometric Poly(ethylene) Glycol Microgels Using a Novel Radical-Free Microfluidic System. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2019; 15:e1900692. [PMID: 30993907 DOI: 10.1002/smll.201900692] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/06/2019] [Revised: 04/04/2019] [Indexed: 06/09/2023]
Abstract
Complex 3D artificial tissue constructs are extensively investigated for tissue regeneration. Frequently, materials and cells are delivered separately without benefitting from the synergistic effect of combined administration. Cell delivery inside a material construct provides the cells with a supportive environment by presenting biochemical, mechanical, and structural signals to direct cell behavior. Conversely, the cell/material interaction is poorly understood at the micron scale and new systems are required to investigate the effect of micron-scale features on cell functionality. Consequently, cells are encapsulated in microgels to avoid diffusion limitations of nutrients and waste and facilitate analysis techniques of single or collective cells. However, up to now, the production of soft cell-loaded microgels by microfluidics is limited to spherical microgels. Here, a novel method is presented to produce monodisperse, anisometric poly(ethylene) glycol microgels to study cells inside an anisometric architecture. These microgels can potentially direct cell growth and can be injected as rod-shaped mini-tissues that further assemble into organized macroscopic and macroporous structures post-injection. Their aspect ratios are adjusted with flow parameters, while mechanical and biochemical properties are altered by modifying the precursors. Encapsulated primary fibroblasts are viable and spread and migrate across the 3D microgel structure.
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Affiliation(s)
- Luis P B Guerzoni
- DWI-Leibniz Institute for Interactive Materials, Forckenbeckstrasse 50, 52074, Aachen, Germany
| | - Jonas C Rose
- DWI-Leibniz Institute for Interactive Materials, Forckenbeckstrasse 50, 52074, Aachen, Germany
| | - David B Gehlen
- DWI-Leibniz Institute for Interactive Materials, Forckenbeckstrasse 50, 52074, Aachen, Germany
| | - Alexander Jans
- DWI-Leibniz Institute for Interactive Materials, Forckenbeckstrasse 50, 52074, Aachen, Germany
| | - Tamàs Haraszti
- DWI-Leibniz Institute for Interactive Materials, Forckenbeckstrasse 50, 52074, Aachen, Germany
| | - Matthias Wessling
- DWI-Leibniz Institute for Interactive Materials, Forckenbeckstrasse 50, 52074, Aachen, Germany
- AVT.CVT, Forckenbeckstrasse 51, 52074, Aachen, Germany
| | - Alexander J C Kuehne
- DWI-Leibniz Institute for Interactive Materials, Forckenbeckstrasse 50, 52074, Aachen, Germany
- Institute of Organic and Macromolecular Chemistry, Ulm University, Albert-Einstein-Allee 11, 89081, Ulm, Germany
| | - Laura De Laporte
- DWI-Leibniz Institute for Interactive Materials, Forckenbeckstrasse 50, 52074, Aachen, Germany
- Institute for Technical and Macromolecular Chemistry, RWTH Aachen, Worringerweg 1-2, 52074, Aachen, Germany
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41
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Taokaew S, Ofuchi M, Kobayashi T. Size Distribution and Characteristics of Chitin Microgels Prepared via Emulsified Reverse-Micelles. MATERIALS 2019; 12:ma12071160. [PMID: 30974746 PMCID: PMC6480158 DOI: 10.3390/ma12071160] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/11/2019] [Revised: 04/06/2019] [Accepted: 04/08/2019] [Indexed: 01/07/2023]
Abstract
Chitin was extracted from local snow crab shell waste and used as a raw material in the fabrication of porous spherical microgels. The chitin microgels were obtained using a batch process of emulsification and, afterward, gelation. The effects of chitin concentrations, oil and water phase ratios (O:W), surfactants, and gelation on the size distribution and morphology of the microgels were investigated. The extracted chitin possessed α-chitin with a degree of acetylation of ~60% and crystallinity of 70%, as confirmed by Fourier Transform Infrared Spectroscopy (FTIR) and X-Ray Powder Diffraction (XRD). In the reverse-micellar emulsification, different chitin concentrations in NaOH solution were used as aqueous phases, and n-hexane media containing Span 80-based surfactants were used as dispersion phases. Various HCl solutions were used as gelling agents. Microgels with sizes ranging from ~5-200 μm were obtained relying on these studied parameters. Under the condition of 3% w/w chitin solution using O:W of 15:1 at 5% w/w of Span 80 (hydrophilic-lipophilic balance; HLB of 4.3), the gelation in the emulsified reverse micelles was better controlled and capable of forming spherical microgel particles with a size of 7.1 ± 0.3 μm, when 800 μL of 1 M HCl was added. The prepared chitin microgel exhibited macro-pore morphology and swelling behavior sensitive to the acidic pH.
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Affiliation(s)
- Siriporn Taokaew
- Department of Materials Science and Technology, School of Engineering, Nagaoka University of Technology, 1603-1, Kamitomioka, Nagaoka, Niigata 940-2188, Japan.
| | - Mitsumasa Ofuchi
- Department of Materials Science and Technology, School of Engineering, Nagaoka University of Technology, 1603-1, Kamitomioka, Nagaoka, Niigata 940-2188, Japan.
| | - Takaomi Kobayashi
- Department of Materials Science and Technology, School of Engineering, Nagaoka University of Technology, 1603-1, Kamitomioka, Nagaoka, Niigata 940-2188, Japan.
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42
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Watanabe T, Motohiro I, Ono T. Microfluidic Formation of Hydrogel Microcapsules with a Single Aqueous Core by Spontaneous Cross-Linking in Aqueous Two-Phase System Droplets. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2019; 35:2358-2367. [PMID: 30626189 DOI: 10.1021/acs.langmuir.8b04169] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
We report a simple process to fabricate monodisperse tetra-arm poly(ethylene glycol) (tetra-PEG) hydrogel microcapsules with an aqueous core and a semipermeable hydrogel shell through the formation of aqueous two-phase system (ATPS) droplets consisting of a dextran-rich core and a tetra-PEG macromonomer-rich shell, followed by a spontaneous cross-end coupling reaction of tetra-PEG macromonomers in the shell. Different from conventional techniques, this process enables for the continuous production of hydrogel microcapsules from water-in-oil emulsion droplets under mild conditions in the absence of radical initiators and external stimuli such as heating and ultraviolet light irradiation. We find that rapid cross-end coupling reaction of tetra-PEG macromonomers in ATPS droplets in the range of pH from 7.4 to 7.8 gives hydrogel microcapsules with a kinetically arrested core-shell structure. The diameter and core-shell ratio of the microcapsules can be easily controlled by adjusting flow rates and ATPS compositions. On the other hand, the slow cross-end coupling reaction of tetra-PEG macromonomers in ATPS droplets at pH 7.0 and lower induces structural change from core-shell to Janus during the reaction, which eventually forms hydrogel microparticles with a thermodynamically stable crescent structure. We believe that these hydrogel microparticles with controlled structures can be used in biomedical fields such as cell encapsulation, biosensors, and drug delivery carriers for sensitive biomolecules.
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Affiliation(s)
- Takaichi Watanabe
- Division of Applied Chemistry, Graduate School of Natural Science , Okayama University , 3-1-1, Tsushima-naka, Kita-ku , Okayama 700-8530 , Japan
| | - Ibuki Motohiro
- Division of Applied Chemistry, Graduate School of Natural Science , Okayama University , 3-1-1, Tsushima-naka, Kita-ku , Okayama 700-8530 , Japan
| | - Tsutomu Ono
- Division of Applied Chemistry, Graduate School of Natural Science , Okayama University , 3-1-1, Tsushima-naka, Kita-ku , Okayama 700-8530 , Japan
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43
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Jung F, Janssen FAL, Ksiazkiewicz A, Caspari A, Mhamdi A, Pich A, Mitsos A. Identifiability Analysis and Parameter Estimation of Microgel Synthesis: A Set-Membership Approach. Ind Eng Chem Res 2019. [DOI: 10.1021/acs.iecr.8b05274] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Falco Jung
- Aachener Verfahrenstechnik-Process Systems Engineering, RWTH Aachen University, 52074 Aachen, Germany
| | - Franca A. L. Janssen
- Aachener Verfahrenstechnik-Process Systems Engineering, RWTH Aachen University, 52074 Aachen, Germany
| | | | - Adrian Caspari
- Aachener Verfahrenstechnik-Process Systems Engineering, RWTH Aachen University, 52074 Aachen, Germany
| | - Adel Mhamdi
- Aachener Verfahrenstechnik-Process Systems Engineering, RWTH Aachen University, 52074 Aachen, Germany
| | - Andrij Pich
- DWI Leibniz Institute for Interactive Materials e.V., 52074 Aachen, Germany
- Institute of Technical and Macromolecular Chemistry, RWTH Aachen University, 52074 Aachen, Germany
| | - Alexander Mitsos
- Aachener Verfahrenstechnik-Process Systems Engineering, RWTH Aachen University, 52074 Aachen, Germany
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44
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Dai Z, Huang S. Functional Dynamics Inside Nano- or Microscale Bio-Hybrid Systems. Front Chem 2018; 6:621. [PMID: 30619829 PMCID: PMC6305405 DOI: 10.3389/fchem.2018.00621] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2018] [Accepted: 11/30/2018] [Indexed: 11/22/2022] Open
Abstract
Soft nano- or microgels made by natural or synthetic polymers have been investigated intensively because of their board applications. Due to their porosity and biocompatibility, nano- or microgels can be integrated with various biologics to form a bio-hybrid system. They can support living cells as a scaffold; entrap bioactive molecules as a drug carrier or encapsulate microorganisms as a semi-permeable membrane. Especially, researchers have created various modes of functional dynamics into these bio-hybrid systems. From one side, the encapsulating materials can respond to the external stimulus and release the cargo. From the other side, cells can respond to physical, or chemical properties of the matrix and differentiate into a specific cell type. With recent advancements of synthetic biology, cells can be further programed to respond to certain signals, and express therapeutics or other functional proteins for various purposes. Thus, the integration of nano- or microgels and programed cells becomes a potential candidate in applications spanning from biotechnology to new medicines. This brief review will first talk about several nano- or microgels systems fabricated by natural or synthetic polymers, and further discuss their applications when integrated with various types of biologics. In particular, we will concentrate on the dynamics embedded in these bio-hybrid systems, to dissect their designs and sophisticated functions.
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Affiliation(s)
- Zhuojun Dai
- Institute for Synthetic Biology, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, China
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45
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Martins CR, Custódio CA, Mano JF. Multifunctional laminarin microparticles for cell adhesion and expansion. Carbohydr Polym 2018; 202:91-98. [PMID: 30287047 PMCID: PMC6443035 DOI: 10.1016/j.carbpol.2018.08.029] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2018] [Revised: 08/07/2018] [Accepted: 08/08/2018] [Indexed: 02/07/2023]
Abstract
Microfabrication technologies have been widely explored to produce microgels that can be assembled in functional constructs for tissue engineering and regenerative medicine applications. Here, we propose microfluidics coupled to a source of UV light to produce multifunctional methacrylated laminarin microparticles with narrow distribution of sizes using photopolymerization. The multifunctional microparticles were loaded with platelet lysates and further conjugated with an adhesive peptide. The adhesive peptides dictated cell adhesiveness to the laminarin microparticles, the incorporation of platelet lysates have resulted in improved cell expansion compared to clear microparticles. Overall, our findings demonstrate that multifunctional methacrylated laminarin microparticles provide an effective support for cell attachment and expansion. Moreover, expanded cells provide the link for microparticles aggregation resulting in robust 3D structures. This suggest the potential for using the methacrylated laminarin microplatforms capable to be assembled by the action of cells to rapidly produce large tissue engineered constructs.
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Affiliation(s)
- C R Martins
- Department of Chemistry, CICECO, Aveiro Institute of Materials, University of Aveiro Campus Universitário de Santiago, 3810-193 Aveiro, Portugal
| | - C A Custódio
- Department of Chemistry, CICECO, Aveiro Institute of Materials, University of Aveiro Campus Universitário de Santiago, 3810-193 Aveiro, Portugal.
| | - J F Mano
- Department of Chemistry, CICECO, Aveiro Institute of Materials, University of Aveiro Campus Universitário de Santiago, 3810-193 Aveiro, Portugal.
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46
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Kim DJ, Park SG, Kim DH, Kim SH. SERS-Active-Charged Microgels for Size- and Charge-Selective Molecular Analysis of Complex Biological Samples. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2018; 14:e1802520. [PMID: 30548922 DOI: 10.1002/smll.201802520] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2018] [Revised: 07/25/2018] [Indexed: 05/27/2023]
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47
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Nys G, Fillet M. Microfluidics contribution to pharmaceutical sciences: From drug discovery to post marketing product management. J Pharm Biomed Anal 2018; 159:348-362. [DOI: 10.1016/j.jpba.2018.07.011] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2018] [Revised: 07/08/2018] [Accepted: 07/10/2018] [Indexed: 12/18/2022]
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48
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Wang J, Cooper RC, He H, Li B, Yang H. Polyamidoamine Dendrimer Microgels: Hierarchical Arrangement of Dendrimers into Micrometer Domains with Expanded Structural Features for Programmable Drug Delivery and Release. Macromolecules 2018; 51:6111-6118. [PMID: 30705466 PMCID: PMC6348485 DOI: 10.1021/acs.macromol.8b01006] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
In this paper, we report on the fabrication of micron-sized dendrimer hydrogels (μDHs) using the water-in-oil (w/o) inverse microemulsion method coupled with the highly efficient aza-Michael addition. EDA core polyamidoamine (PAMAM) dendrimer G5 (10 w%) and polyethylene glycol diacrylate (PEG-DA, M n = 575 g/mol) (the molar ratio of amine/acrylate = 1/1) were dissolved in the water phase and added to hexane in the presence of surfactants span 80/tween 80 (5/1, w/w) (volume ratio of hexane to surfactants: 70:1) to form w/o microemulsions, in which PAMAM G5 cross-links with PEG-DA via the aza-Michael addition reaction. The resulting microgels are within 3-5 μm with relatively narrow size distribution. μDHs are pH-responsive degradable. They show good cytocompatibility and do not cause acute toxicity in vivo. Furthermore, they can realize a high loading of the hydrophobic drug CPT and enter the cells in the form of particles. The CPT and CPT/dendrimer complex can be slowly released following the zero-order release kinetics. Taken together, μDHs possessing hierarchically ordered dendrimers in micron domains represent a new class of microparticles with expanded structural features for programmable drug delivery and release.
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Affiliation(s)
- Juan Wang
- Department of Chemical and Life Science Engineering,
Virginia Commonwealth University, Richmond, Virginia 23219, United States
| | - Remy C Cooper
- Department of Biomedical Engineering, Virginia Commonwealth
University, Richmond, Virginia 23284, United States
| | - Hongliang He
- Department of Chemical and Life Science Engineering,
Virginia Commonwealth University, Richmond, Virginia 23219, United States
| | - Boxuan Li
- Department of Chemical and Life Science Engineering,
Virginia Commonwealth University, Richmond, Virginia 23219, United States
| | - Hu Yang
- Department of Chemical and Life Science Engineering,
Virginia Commonwealth University, Richmond, Virginia 23219, United States
- Department of Pharmaceutics, Virginia Commonwealth
University, Richmond, Virginia 23298, United States
- Massey Cancer Center, Virginia Commonwealth University,
Richmond, Virginia 23298, United States
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Agrawal G, Agrawal R. Stimuli-Responsive Microgels and Microgel-Based Systems: Advances in the Exploitation of Microgel Colloidal Properties and Their Interfacial Activity. Polymers (Basel) 2018; 10:E418. [PMID: 30966453 PMCID: PMC6415239 DOI: 10.3390/polym10040418] [Citation(s) in RCA: 52] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2018] [Revised: 04/03/2018] [Accepted: 04/03/2018] [Indexed: 11/22/2022] Open
Abstract
In this paper, recent developments in the chemical design of functional microgels are summarized. A wide range of available synthetic methods allows the incorporation of various reactive groups, charges, or biological markers inside the microgel network, thus controlling the deformation and swelling degree of the resulting smart microgels. These microgels can respond to various stimuli, such as temperature, pH, light, electric field, etc. and can show unique deformation behavior at the interface. Due to their switchability and interfacial properties, these smart microgels are being extensively explored for various applications, such as antifouling coatings, cell encapsulation, catalysis, controlled drug delivery, and tissue engineering.
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Affiliation(s)
- Garima Agrawal
- Department of Polymer and Process Engineering, Indian Institute of Technology Roorkee, Saharanpur Campus, Paper Mill Road, Saharanpur 247001, Uttar Pradesh, India.
| | - Rahul Agrawal
- Laboratory of Pathology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892-1500, USA.
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