501
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Dong Y, Jin G, Ji C, He R, Lin M, Zhao X, Li A, Lu TJ, Xu F. Non-invasive tracking of hydrogel degradation using upconversion nanoparticles. Acta Biomater 2017; 55:410-419. [PMID: 28428038 DOI: 10.1016/j.actbio.2017.04.016] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2016] [Revised: 04/13/2017] [Accepted: 04/13/2017] [Indexed: 12/11/2022]
Abstract
Tracking the distribution and degradation of hydrogels in vivo is important for various applications including tissue engineering and drug delivery. Among various imaging modalities, fluorescence imaging has attracted intensive attention due to their high sensitivity, low cost and easy operation. Particularly, upconversion nanoparticles (UCNPs) that emit visible lights upon near-infrared (NIR) light excitation as tracking probes are promising in deciphering the fate of hydrogels after transplantation. Herein, we reported a facile and non-invasive in vivo hydrogel tracking method using UCNPs, where the degradation of hydrogels was determined using the decrease in fluorescence intensity from the UCNPs encapsulated in the hydrogels. We found that the change in the fluorescence intensity from the UCNPs was well consistent with that of the fluorescein isothiocyanate (FITC) covalently conjugated to hydrogels and also with the weight change of the hydrogels, suggesting the accuracy of the UCNPs in tracking the degradation of hydrogels. Furthermore, the in vivo fluorescence signals were only observed from the UCNPs instead of FITC after implantation for 7days due to the deep tissue penetration of UCNPs, demonstrating the capability of UCNPs in longitudinal, consecutive and non-invasive monitoring the in vivo degradation of hydrogels without causing any damage to the major organs (heart, lung, liver and kidney) of model rats. This study thus paves the way for monitoring the in vivo behaviors of biomimetic materials via deep tissue imaging with great clinical translation potentials. STATEMENT OF SIGNIFICANCE Long-term noninvasive in vivo tracking of the distribution and degradation of biodegradable hydrogels using fluorescent probes is important in tissue regeneration and drug delivery. Unlike the widely used fluorescent dyes and quantum dots (QDs) that suffer from photobleaching and undesired toxicity, upconversion nanoparticles (UCNPs) with high stability, deep tissue penetration as tracking probes are promising in deciphering the fate of hydrogels after transplantation. Herein, we reported a noninvasive in vivo hydrogel tracking method using UCNPs and found that the fluorescence intensity change from the UCNPs was well consistent with the weight change of the hydrogels, suggesting the accuracy of UCNPs in tracking hydrogel degradation. This study provides inspirations on developing advanced NIR light regulated probes with great clinical translation potentials.
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502
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Dinh ND, Luo R, Christine MTA, Lin WN, Shih WC, Goh JCH, Chen CH. Effective Light Directed Assembly of Building Blocks with Microscale Control. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2017; 13. [PMID: 28481437 DOI: 10.1002/smll.201700684] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/01/2017] [Indexed: 05/14/2023]
Abstract
Light-directed forces have been widely used to pattern micro/nanoscale objects with precise control, forming functional assemblies. However, a substantial laser intensity is required to generate sufficient optical gradient forces to move a small object in a certain direction, causing limited throughput for applications. A high-throughput light-directed assembly is demonstrated as a printing technology by introducing gold nanorods to induce thermal convection flows that move microparticles (diameter = 40 µm to several hundreds of micrometers) to specific light-guided locations, forming desired patterns. With the advantage of effective light-directed assembly, the microfluidic-fabricated monodispersed biocompatible microparticles are used as building blocks to construct a structured assembly (≈10 cm scale) in ≈2 min. The control with microscale precision is approached by changing the size of the laser light spot. After crosslinking assembly of building blocks, a novel soft material with wanted pattern is approached. To demonstrate its application, the mesenchymal stem-cell-seeded hydrogel microparticles are prepared as functional building blocks to construct scaffold-free tissues with desired structures. This light-directed fabrication method can be applied to integrate different building units, enabling the bottom-up formation of materials with precise control over their internal structure for bioprinting, tissue engineering, and advanced manufacturing.
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Affiliation(s)
- Ngoc-Duy Dinh
- Department of Biomedical Engineering, National University of Singapore, 21 Lower Kent Ridge Road, Singapore, 119077
| | - Rongcong Luo
- Department of Biomedical Engineering, National University of Singapore, 21 Lower Kent Ridge Road, Singapore, 119077
| | | | - Weikang Nicholas Lin
- Department of Biomedical Engineering, National University of Singapore, 21 Lower Kent Ridge Road, Singapore, 119077
| | - Wei-Chuan Shih
- Departments of Electrical and Computer Engineering, Biomedical Engineering and Chemistry, University of Houston, 4800 Calhoun Rd, Houston, TX, 77004, USA
| | - James Cho-Hong Goh
- Department of Biomedical Engineering, National University of Singapore, 21 Lower Kent Ridge Road, Singapore, 119077
- Department of Orthopaedic Surgery, Yong Loo Lin School of Medicine, National University of Singapore, 21 Lower Kent Ridge Road, Singapore, 119077
| | - Chia-Hung Chen
- Department of Biomedical Engineering, National University of Singapore, 21 Lower Kent Ridge Road, Singapore, 119077
- Singapore Institute of Neurotechnology (SINAPSE), National University of Singapore, 21 Lower Kent Ridge Road, Singapore, 119077
- Biomedical Institute for Global Health Research & Technology (BIGHEART), National University of Singapore, 21 Lower Kent Ridge Road, Singapore, 119077
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503
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Robinson KG, Scott RA, Hesek AM, Woodford EJ, Amir W, Planchon TA, Kiick KL, Akins RE. Reduced arterial elasticity due to surgical skeletonization is ameliorated by abluminal PEG hydrogel. Bioeng Transl Med 2017; 2:222-232. [PMID: 28932820 PMCID: PMC5579730 DOI: 10.1002/btm2.10060] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2016] [Revised: 02/15/2017] [Accepted: 03/06/2017] [Indexed: 12/17/2022] Open
Abstract
Arteries for bypass grafting are harvested either with neighboring tissue attached or as skeletonized vessels that are free of surrounding tissue. There are significant benefits to skeletonization, but reports suggest that skeletonized vessels may develop structural defects and are at risk for atherosclerosis. We investigated the specific short‐term effects of skeletonization on carotid artery biomechanics and microanatomy in a rabbit model. Six carotid arteries were surgically skeletonized. To support healing, three of these received polyethylene glycol hydrogel injected along their exterior surfaces. M‐mode ultrasonography was used to track circumferential cyclic strain in the skeletonized, hydrogel‐treated, and contralateral vessels. On day 21, the arteries were harvested, and vessel structure was assessed by histology, immunofluorescence microscopy, two‐photon elastin autofluorescence, and second harmonic generation (SHG) microscopy. Intimal‐medial thickness appeared unaffected by skeletonization, but the SHG signals indicated significant changes in collagen turnover in the adventitia. Skeletonized arteries also exhibited significantly decreased radial compliance (circumferential cyclic strain dropped ∼30%) and decreased numbers of elastic laminae (9.1 ± 2.0 to 2.3 ± 1.4). Hydrogel treatment protected against these effects with treated vessels maintaining normal mechanical properties. These results indicate that arterial skeletonization triggers immediate effects on vessel remodeling and reduced vessel compliance resulting in specific tissue alterations within 21 days, but that these effects can be attenuated by the placement of hydrogel on the exterior surface of the skeletonized vessel.
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Affiliation(s)
- Karyn G Robinson
- Nemours - Alfred I. duPont Hospital for Children Wilmington DE1 9803
| | - Rebecca A Scott
- Nemours - Alfred I. duPont Hospital for Children Wilmington DE1 9803.,Dept. of Materials Science & Engineering University of Delaware Newark DE 19716
| | - Anne M Hesek
- Nemours - Alfred I. duPont Hospital for Children Wilmington DE1 9803
| | - Edward J Woodford
- Nemours - Alfred I. duPont Hospital for Children Wilmington DE1 9803
| | - Wafa Amir
- Dept. of Physics and Engineering, Optical Science Center for Applied Research Delaware State University Dover DE 19901
| | - Thomas A Planchon
- Dept. of Physics and Engineering, Optical Science Center for Applied Research Delaware State University Dover DE 19901
| | - Kristi L Kiick
- Nemours - Alfred I. duPont Hospital for Children Wilmington DE1 9803.,Dept. of Materials Science & Engineering University of Delaware Newark DE 19716.,Dept. of Biomedical Engineering University of Delaware Newark DE 19716
| | - Robert E Akins
- Nemours - Alfred I. duPont Hospital for Children Wilmington DE1 9803.,Dept. of Materials Science & Engineering University of Delaware Newark DE 19716.,Dept. of Biomedical Engineering University of Delaware Newark DE 19716
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504
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Abstract
Droplet microfluidics generates and manipulates discrete droplets through immiscible multiphase flows inside microchannels. Due to its remarkable advantages, droplet microfluidics bears significant value in an extremely wide range of area. In this review, we provide a comprehensive and in-depth insight into droplet microfluidics, covering fundamental research from microfluidic chip fabrication and droplet generation to the applications of droplets in bio(chemical) analysis and materials generation. The purpose of this review is to convey the fundamentals of droplet microfluidics, a critical analysis on its current status and challenges, and opinions on its future development. We believe this review will promote communications among biology, chemistry, physics, and materials science.
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Affiliation(s)
- Luoran Shang
- State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University , Nanjing 210096, China
| | - Yao Cheng
- State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University , Nanjing 210096, China
| | - Yuanjin Zhao
- State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University , Nanjing 210096, China
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505
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Kamperman T, Henke S, Zoetebier B, Ruiterkamp N, Wang R, Pouran B, Weinans H, Karperien M, Leijten J. Nanoemulsion-induced enzymatic crosslinking of tyramine-functionalized polymer droplets. J Mater Chem B 2017; 5:4835-4844. [PMID: 32263999 DOI: 10.1039/c7tb00686a] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
In situ gelation of water-in-oil polymer emulsions is a key method to produce hydrogel particles. Although this approach is in principle ideal for encapsulating bioactive components such as cells, the oil phase can interfere with straightforward presentation of crosslinker molecules. Several approaches have been developed to induce in-emulsion gelation by exploiting the triggered generation or release of crosslinker molecules. However, these methods typically rely on photo- or acid-based reactions that are detrimental to cell survival and functioning. In this work, we demonstrate the diffusion-based supplementation of small molecules for the in-emulsion gelation of multiple tyramine-functionalized polymers via enzymatic crosslinking using a H2O2/oil nanoemulsion. This strategy is compatible with various emulsification techniques, thereby readily supporting the formation of monodisperse hydrogel particles spanning multiple length scales ranging from the nano- to the millimeter. As proof of principle, we leveraged droplet microfluidics in combination with the cytocompatible nature of enzymatic crosslinking to engineer hollow cell-laden hydrogel microcapsules that support the formation of viable and functional 3D microtissues. The straightforward, universal, and cytocompatible nature of nanoemulsion-induced enzymatic crosslinking facilitates its rapid and widespread use in numerous food, pharma, and life science applications.
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Affiliation(s)
- Tom Kamperman
- Department of Developmental BioEngineering, MIRA Institute for Biomedical Technology and Technical Medicine, University of Twente, Drienerlolaan 5, 7522NB Enschede, The Netherlands.
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506
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Gan Y, Li P, Wang L, Mo X, Song L, Xu Y, Zhao C, Ouyang B, Tu B, Luo L, Zhu L, Dong S, Li F, Zhou Q. An interpenetrating network-strengthened and toughened hydrogel that supports cell-based nucleus pulposus regeneration. Biomaterials 2017; 136:12-28. [PMID: 28505597 DOI: 10.1016/j.biomaterials.2017.05.017] [Citation(s) in RCA: 73] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2016] [Revised: 05/06/2017] [Accepted: 05/08/2017] [Indexed: 12/12/2022]
Abstract
Hydrogel is a suitable scaffold for the nucleus pulposus (NP) regeneration. However, its unmatched mechanical properties lead to implant failure in late-stage disc degeneration because of structural failure and implant extrusion after long-term compression. In this study, we evaluated an interpenetrating network (IPN)-strengthened and toughened hydrogel for NP regeneration, using dextran and gelatin as the primary network while poly (ethylene glycol) as the secondary network. The aim of this study was to realize the NP regeneration using the hydrogel. To achieve this, we optimized its properties by adjusting the mass ratios of the secondary/primary networks and determining the best preparation conditions for NP regeneration in a series of biomechanical, cytocompatibility, tissue engineering, and in vivo study. We found the optimal formulation of the IPN hydrogel, at a secondary/primary network ratio of 1:4, exhibited high toughness (the compressive strain reached 86%). The encapsulated NP cells showed increasing proliferation, cell clustering and matrix deposition. Furthermore, the hydrogel could support long-term cell retention and survival in the rat IVDs. It facilitated rehydration and regeneration of porcine degenerative NPs. In conclusion, this study demonstrates the tough IPN hydrogel could be a promising candidate for functional disc regeneration in future.
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Affiliation(s)
- Yibo Gan
- National & Regional United Engineering Laboratory of Tissue Engineering, Department of Orthopedics, Southwest Hospital, Third Military Medical University, Chongqing 400038, PR China
| | - Pei Li
- National & Regional United Engineering Laboratory of Tissue Engineering, Department of Orthopedics, Southwest Hospital, Third Military Medical University, Chongqing 400038, PR China
| | - Liyuan Wang
- National & Regional United Engineering Laboratory of Tissue Engineering, Department of Orthopedics, Southwest Hospital, Third Military Medical University, Chongqing 400038, PR China
| | - Xiumei Mo
- College of Chemistry and Chemical Engineering and Biological Engineering, Donghua University, Shanghai 201620, PR China
| | - Lei Song
- National & Regional United Engineering Laboratory of Tissue Engineering, Department of Orthopedics, Southwest Hospital, Third Military Medical University, Chongqing 400038, PR China
| | - Yuan Xu
- Department of Orthopedics, Xinqiao Hospital, Third Military Medical University, Chongqing, PR China
| | - Chen Zhao
- National & Regional United Engineering Laboratory of Tissue Engineering, Department of Orthopedics, Southwest Hospital, Third Military Medical University, Chongqing 400038, PR China
| | - Bin Ouyang
- National & Regional United Engineering Laboratory of Tissue Engineering, Department of Orthopedics, Southwest Hospital, Third Military Medical University, Chongqing 400038, PR China
| | - Bing Tu
- National & Regional United Engineering Laboratory of Tissue Engineering, Department of Orthopedics, Southwest Hospital, Third Military Medical University, Chongqing 400038, PR China
| | - Lei Luo
- National & Regional United Engineering Laboratory of Tissue Engineering, Department of Orthopedics, Southwest Hospital, Third Military Medical University, Chongqing 400038, PR China
| | - Linyong Zhu
- Key Laboratory for Advanced Materials, Institute of Fine Chemicals, East China University of Science and Technology, Shanghai 200237, PR China
| | - Shiwu Dong
- Department of Biomedical Materials Science, School of Biomedical Engineering, Third Military Medical University, Chongqing 400038, PR China
| | - Fuyou Li
- Department of Chemistry & State Key Laboratory of Molecular Engineering of Polymers, Fudan University, Shanghai 200433, PR China
| | - Qiang Zhou
- National & Regional United Engineering Laboratory of Tissue Engineering, Department of Orthopedics, Southwest Hospital, Third Military Medical University, Chongqing 400038, PR China.
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507
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Stem cell culture and differentiation in microfluidic devices toward organ-on-a-chip. Future Sci OA 2017; 3:FSO187. [PMID: 28670476 PMCID: PMC5481871 DOI: 10.4155/fsoa-2016-0091] [Citation(s) in RCA: 83] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2016] [Accepted: 02/21/2017] [Indexed: 02/07/2023] Open
Abstract
Microfluidic lab-on-a-chip provides a new platform with unique advantages to mimic complex physiological microenvironments in vivo and has been increasingly exploited to stem cell research. In this review, we highlight recent advances of microfluidic devices for stem cell culture and differentiation toward the development of organ-on-a-chip, especially with an emphasis on vital innovations within the last 2 years. Various aspects for improving on-chip stem-cell culture and differentiation, particularly toward organ-on-a-chip, are discussed, along with microenvironment control, surface modification, extracellular scaffolds, high throughput and stimuli. The combination of microfluidic technologies and stem cells hold great potential toward versatile systems of ‘organ-on-a-chip’ as desired.
Adapted with permission from [1–8]. Stem cells, capable of self-renewing and differentiating into cells of various tissue types, are drawing more and more attention for their enormous potential in many clinically associated applications that include drug screening, disease modeling and regenerative medicine. Conventional cell culture methods, however, have proven to be difficult to mimic in vivo like microenvironments and to provide a number of well-controlled stimuli that are critical for stem cell culture and differentiation. In contrast, microfluidic devices offer new capacities and unique advantages to mimic complex physiological microenvironments in vivo, and has been increasingly applied to stem cell research.
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508
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Udenni Gunathilake TMS, Ching YC, Ching KY, Chuah CH, Abdullah LC. Biomedical and Microbiological Applications of Bio-Based Porous Materials: A Review. Polymers (Basel) 2017; 9:E160. [PMID: 30970839 PMCID: PMC6431923 DOI: 10.3390/polym9050160] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2017] [Revised: 04/15/2017] [Accepted: 04/25/2017] [Indexed: 12/27/2022] Open
Abstract
Extensive employment of biomaterials in the areas of biomedical and microbiological applications is considered to be of prime importance. As expected, oil based polymer materials were gradually replaced by natural or synthetic biopolymers due to their well-known intrinsic characteristics such as biodegradability, non-toxicity and biocompatibility. Literature on this subject was found to be expanding, especially in the areas of biomedical and microbiological applications. Introduction of porosity into a biomaterial broadens the scope of applications. In addition, increased porosity can have a beneficial effect for the applications which exploit their exceptional ability of loading, retaining and releasing of fluids. Different applications require a unique set of pore characteristics in the biopolymer matrix. Various pore morphologies have different characteristics and contribute different performances to the biopolymer matrix. Fabrication methods for bio-based porous materials more related to the choice of material. By choosing the appropriate combination of fabrication technique and biomaterial employment, one can obtain tunable pore characteristic to fulfill the requirements of desired application. In our previous review, we described the literature related to biopolymers and fabrication techniques of porous materials. This paper we will focus on the biomedical and microbiological applications of bio-based porous materials.
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Affiliation(s)
- T M S Udenni Gunathilake
- Department of Chemical Engineering, Faculty of Engineering, University of Malaya, Kuala Lumpur 50603, Malaysia.
| | - Yern Chee Ching
- Department of Chemical Engineering, Faculty of Engineering, University of Malaya, Kuala Lumpur 50603, Malaysia.
| | - Kuan Yong Ching
- University of Reading Malaysia, Persiaran Graduan, Kota Ilmu, Educity, Iskandar Puteri Johor 79200, Malaysia.
| | - Cheng Hock Chuah
- Department of Chemistry, Faculty of Science, University of Malaya, Kuala Lumpur 50603, Malaysia.
| | - Luqman Chuah Abdullah
- Department of Chemical Engineering, Faculty of Engineering, Universiti Putra Malaysia, Serdang 43400, Malaysia.
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509
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Abstract
New developments in accelerating wound healing can have immense beneficial socioeconomic impact. The wound healing process is a highly orchestrated series of mechanisms where a multitude of cells and biological cascades are involved. The skin battery and current of injury mechanisms have become topics of interest for their influence in chronic wounds. Electrostimulation therapy of wounds has shown to be a promising treatment option with no-device-related adverse effects. This review presents an overview of the understanding and use of applied electrical current in various aspects of wound healing. Rapid clinical translation of the evolving understanding of biomolecular mechanisms underlying the effects of electrical simulation on wound healing would positively impact upon enhancing patient’s quality of life.
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Affiliation(s)
- Jerome Hunckler
- UCL Division of Surgery and Interventional Sciences, Faculty of Medical Sciences, University College London, London, UK
| | - Achala de Mel
- UCL Division of Surgery and Interventional Sciences, Faculty of Medical Sciences, University College London, London, UK
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510
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Stoecklein D, Lore KG, Davies M, Sarkar S, Ganapathysubramanian B. Deep Learning for Flow Sculpting: Insights into Efficient Learning using Scientific Simulation Data. Sci Rep 2017; 7:46368. [PMID: 28402332 PMCID: PMC5389406 DOI: 10.1038/srep46368] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2016] [Accepted: 03/15/2017] [Indexed: 01/29/2023] Open
Abstract
A new technique for shaping microfluid flow, known as flow sculpting, offers an unprecedented level of passive fluid flow control, with potential breakthrough applications in advancing manufacturing, biology, and chemistry research at the microscale. However, efficiently solving the inverse problem of designing a flow sculpting device for a desired fluid flow shape remains a challenge. Current approaches struggle with the many-to-one design space, requiring substantial user interaction and the necessity of building intuition, all of which are time and resource intensive. Deep learning has emerged as an efficient function approximation technique for high-dimensional spaces, and presents a fast solution to the inverse problem, yet the science of its implementation in similarly defined problems remains largely unexplored. We propose that deep learning methods can completely outpace current approaches for scientific inverse problems while delivering comparable designs. To this end, we show how intelligent sampling of the design space inputs can make deep learning methods more competitive in accuracy, while illustrating their generalization capability to out-of-sample predictions.
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Affiliation(s)
| | - Kin Gwn Lore
- Iowa State University, Mechanical Engineering, Ames, 50011, USA
| | - Michael Davies
- Iowa State University, Mechanical Engineering, Ames, 50011, USA
| | - Soumik Sarkar
- Iowa State University, Mechanical Engineering, Ames, 50011, USA
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511
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Wu RX, Yin Y, He XT, Li X, Chen FM. Engineering a Cell Home for Stem Cell Homing and Accommodation. ACTA ACUST UNITED AC 2017; 1:e1700004. [PMID: 32646164 DOI: 10.1002/adbi.201700004] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2017] [Revised: 02/27/2017] [Indexed: 12/14/2022]
Abstract
Distilling complexity to advance regenerative medicine from laboratory animals to humans, in situ regeneration will continue to evolve using biomaterial strategies to drive endogenous cells within the human body for therapeutic purposes; this approach avoids the need for delivering ex vivo-expanded cellular materials. Ensuring the recruitment of a significant number of reparative cells from an endogenous source to the site of interest is the first step toward achieving success. Subsequently, making the "cell home" cell-friendly by recapitulating the natural extracellular matrix (ECM) in terms of its chemistry, structure, dynamics, and function, and targeting specific aspects of the native stem cell niche (e.g., cell-ECM and cell-cell interactions) to program and steer the fates of those recruited stem cells play equally crucial roles in yielding a therapeutically regenerative solution. This review addresses the key aspects of material-guided cell homing and the engineering of novel biomaterials with desirable ECM composition, surface topography, biochemistry, and mechanical properties that can present both biochemical and physical cues required for in situ tissue regeneration. This growing body of knowledge will likely become a design basis for the development of regenerative biomaterials for, but not limited to, future in situ tissue engineering and regeneration.
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Affiliation(s)
- Rui-Xin Wu
- State Key Laboratory of Military Stomatology, Department of Periodontology, School of Stomatology, Fourth Military Medical University, Xi'an, P. R. China.,National Clinical Research Center for Oral Diseases, Department of Periodontology, School of Stomatology, Fourth Military Medical University, Xi'an, P.R. China
| | - Yuan Yin
- State Key Laboratory of Military Stomatology, Department of Periodontology, School of Stomatology, Fourth Military Medical University, Xi'an, P. R. China.,National Clinical Research Center for Oral Diseases, Department of Periodontology, School of Stomatology, Fourth Military Medical University, Xi'an, P.R. China
| | - Xiao-Tao He
- State Key Laboratory of Military Stomatology, Department of Periodontology, School of Stomatology, Fourth Military Medical University, Xi'an, P. R. China.,National Clinical Research Center for Oral Diseases, Department of Periodontology, School of Stomatology, Fourth Military Medical University, Xi'an, P.R. China
| | - Xuan Li
- State Key Laboratory of Military Stomatology, Department of Periodontology, School of Stomatology, Fourth Military Medical University, Xi'an, P. R. China.,National Clinical Research Center for Oral Diseases, Department of Periodontology, School of Stomatology, Fourth Military Medical University, Xi'an, P.R. China
| | - Fa-Ming Chen
- State Key Laboratory of Military Stomatology, Department of Periodontology, School of Stomatology, Fourth Military Medical University, Xi'an, P. R. China.,National Clinical Research Center for Oral Diseases, Department of Periodontology, School of Stomatology, Fourth Military Medical University, Xi'an, P.R. China
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512
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Zhu F, Wang C, Yang S, Wang Q, Liang F, Liu C, Qiu D, Qu X, Hu Z, Yang Z. Injectable tissue adhesive composite hydrogel with fibroblasts for treating skin defects. J Mater Chem B 2017; 5:2416-2424. [PMID: 32264549 DOI: 10.1039/c7tb00384f] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
In this work, an injectable composite hydrogel was synthesized via a unique way of crosslinking glycol chitosan (GC) with silica nano-particles (SiNP) through non-chemical interactions, and was then applied as a kind of wound dressing. Gelation was achieved through the incorporation of SiNPs with the GC segments in aqueous solution, therefore strictly confining the movement of the solubilized polymer chains. Rheology tests showed that the sol-gel transition and the moduli of the hydrogel were influenced by the composition of the two components, the size of the nano-particles and the conformation of the polymers. Using such a strategy, tissue adhesion properties of GC were well-preserved in the GC/SiNP hydrogel and therefore it gains gluey properties toward biological tissues as demonstrated through the adhesion of two pieces of mouse skin, obtaining a lap-shear stretching force of ca. 90 kPa. This characteristic, together with the injectability, allowed the hydrogel to be administrated directly on the wound site and to fill the wound area. Meanwhile, the hydrogel also works as a carrier of protein and cells. The in situ encapsulation of fibroblasts enabled the promising properties of the GC/SiNP hydrogel to be used for treating full-thickness skin defects in a mouse model, resulting in the favorable growth of hair follicles and microvessels, hence reducing the risk of scar formation.
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Affiliation(s)
- Feiyan Zhu
- College of Materials Science and Opto-Electronic Technology, University of Chinese Academy of Sciences, Beijing 100049, China
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513
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Levengood SL, Erickson AE, Chang FC, Zhang M. Chitosan-Poly(caprolactone) Nanofibers for Skin Repair. J Mater Chem B 2017; 5:1822-1833. [PMID: 28529754 PMCID: PMC5433941 DOI: 10.1039/c6tb03223k] [Citation(s) in RCA: 66] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Dermal wounds, both acute and chronic, represent a significant clinical challenge and therefore the development of novel biomaterial-based skin substitutes to promote skin repair is essential. Nanofibers have garnered attention as materials to promote skin regeneration due to the similarities in morphology and dimensionality between nanofibers and native extracellular matrix proteins, which are critical in guiding cutaneous wound healing. Electrospun chitosan-poly(caprolactone) (CPCL) nanofiber scaffolds, which combine the important intrinsic biological properties of chitosan and the mechanical integrity and stability of PCL, were evaluated as skin tissue engineering scaffolds using a mouse cutaneous excisional skin defect model. Gross assessment of wound size and measurement of defect recovery over time as well as histological evaluation of wound healing showed that CPCL nanofiber scaffolds increased wound healing rate and promoted more complete wound closure as compared with Tegaderm, a commercially available occlusive dressing. CPCL nanofiber scaffolds represent a biomimetic approach to skin repair by serving as an immediately available provisional matrix to promote wound closure. These nanofiber scaffolds may have significant potential as a skin substitute or as the basis for more complex skin tissue engineering constructs involving integration with biologics.
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Affiliation(s)
- Sheeny Lan Levengood
- Department of Materials Science & Engineering, University of Washington, Seattle, Washington 98195, USA
| | - Ariane E. Erickson
- Department of Materials Science & Engineering, University of Washington, Seattle, Washington 98195, USA
| | - Fei-chien Chang
- Department of Materials Science & Engineering, University of Washington, Seattle, Washington 98195, USA
| | - Miqin Zhang
- Department of Materials Science & Engineering, University of Washington, Seattle, Washington 98195, USA
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514
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Siltanen C, Diakatou M, Lowen J, Haque A, Rahimian A, Stybayeva G, Revzin A. One step fabrication of hydrogel microcapsules with hollow core for assembly and cultivation of hepatocyte spheroids. Acta Biomater 2017; 50:428-436. [PMID: 28069506 DOI: 10.1016/j.actbio.2017.01.010] [Citation(s) in RCA: 55] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2016] [Revised: 12/15/2016] [Accepted: 01/05/2017] [Indexed: 12/16/2022]
Abstract
3D hepatic microtissues can serve as valuable liver analogues for cell-based therapies and for hepatotoxicity screening during preclinical drug development. However, hepatocytes rapidly dedifferentiate in vitro, and typically require 3D culture systems or co-cultures for phenotype rescue. In this work we present a novel microencapsulation strategy, utilizing coaxial flow-focusing droplet microfluidics to fabricate microcapsules with liquid core and poly(ethylene glycol) (PEG) gel shell. When entrapped inside these capsules, primary hepatocytes rapidly formed cell-cell contacts and assembled into compact spheroids. High levels of hepatic function were maintained inside the capsules for over ten days. The microencapsulation approach described here is compatible with difficult-to-culture primary epithelial cells, allows for tuning gel mechanical properties and diffusivity, and may be used in the future for high density suspension cell cultures. STATEMENT OF SIGNIFICANCE Our paper combines an interesting new way for making capsules with cultivation of difficult-to-maintain primary epithelial cells (hepatocytes). The microcapsules described here will enable high density suspension culture of hepatocytes or other cells and may be used as building blocks for engineering tissues.
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515
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Barker EC, Martin AD, Garvey CJ, Goh CY, Jones F, Mocerino M, Skelton BW, Ogden MI, Becker T. Thermal annealing behaviour and gel to crystal transition of a low molecular weight hydrogelator. SOFT MATTER 2017; 13:1006-1011. [PMID: 28083581 DOI: 10.1039/c6sm02431a] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
The thermal annealing behaviour of an electrolyte-triggered calixarene hydrogelator is found to depend strongly on the specific metal chloride used. While the lithium chloride gel showed typical gel-sol transitions as a function of temperature, the magnesium chloride gel was found to repeatedly strengthen with heat-cool cycles. Structural investigations using small-angle neutron scattering, and scanning probe microscopy, suggest that the annealing behaviour is associated with a change in morphology of the fibrous structures supporting the gel. On prolonged standing at room temperature, the magnesium chloride gel underwent a gel-crystal transition, with the collapsing gel accompanied by the deposition of crystals of a magnesium complex of the proline-functionalised calix[4]arene gelator.
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Affiliation(s)
- Emily C Barker
- Department of Chemistry and Nanochemistry Research Institute, Curtin University, GPO Box U1987, Perth, Western Australia 6845, Australia.
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516
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Zhao X, Sun X, Yildirimer L, Lang Q, Lin ZYW, Zheng R, Zhang Y, Cui W, Annabi N, Khademhosseini A. Cell infiltrative hydrogel fibrous scaffolds for accelerated wound healing. Acta Biomater 2017; 49:66-77. [PMID: 27826004 PMCID: PMC5296408 DOI: 10.1016/j.actbio.2016.11.017] [Citation(s) in RCA: 189] [Impact Index Per Article: 27.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2016] [Revised: 10/21/2016] [Accepted: 11/03/2016] [Indexed: 12/11/2022]
Abstract
Development of natural protein-based fibrous scaffolds with tunable physical properties and biocompatibility is highly desirable to construct three-dimensional (3D), fully cellularized scaffolds for wound healing. Herein, we demonstrated a simple and effective technique to construct electrospun 3D fibrous scaffolds for accelerated wound healing using a photocrosslinkable hydrogel based on gelatin methacryloyl (GelMA). We found that the physical properties of the photocrosslinkable hydrogel including water retention, stiffness, strength, elasticity and degradation can be tailored by changing the light exposure time. We further observed that the optimized hydrogel fibrous scaffolds which were soft and elastic could support cell adhesion, proliferation and migration into the whole scaffolds, facilitating regeneration and formation of cutaneous tissues within two weeks. Such tunable characteristics of the fibrous GelMA scaffolds distinguished them from other reported substrates developed for reconstruction of wound defects including glutaraldehyde-crosslinked gelatin or poly (lactic-co-glycolic acid) (PLGA), whose physical and chemical properties were difficult to modify to allow cell infiltration into the 3D scaffolds for tissue regeneration. We anticipate that the ability to become fully cellularized will make the engineered GelMA fibrous scaffolds suitable for widespread applications as skin substitutes or wound dressings. STATEMENT OF SIGNIFICANCE In present study, we generate three-dimensional photocrosslinkable gelatin (GelMA)-based fibrous scaffolds with tunable physical and biological properties by using a combined photocrosslinking/electrospinning approach. The developed GelMA fibrous scaffolds can not only support cell viability and cell adhesion, but also facilitate cell migration and proliferation, accelerating regeneration and formation of cutaneous tissues. In addition, the physical properties of the engineered fibrous GelMA hydrogel including water retention capability, mechanical properties and biodegradability can be tuned to accommodate different patients' needs, making it a promising candidate for skin tissue engineering.
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Affiliation(s)
- Xin Zhao
- Biomaterials Innovation Research Center, Division of Biomedical Engineering, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02139, USA; School of Life Science and Technology, Xi'an Jiaotong University, Xi'an, Shaanxi 710049, China; Bioinspired Engineering and Biomechanics Center, Xi'an Jiaotong University, Shaanxi 710049, China
| | - Xiaoming Sun
- Department of Plastic and Reconstructive Surgery, Shanghai Ninth People's Hospital Affiliated to Shanghai Jiaotong University of Medicine, Shanghai 200011, China
| | - Lara Yildirimer
- Biomaterials Innovation Research Center, Division of Biomedical Engineering, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02139, USA
| | - Qi Lang
- Biomaterials Innovation Research Center, Division of Biomedical Engineering, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02139, USA
| | - Zhi Yuan William Lin
- Biomaterials Innovation Research Center, Division of Biomedical Engineering, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02139, USA
| | - Reila Zheng
- Biomaterials Innovation Research Center, Division of Biomedical Engineering, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02139, USA
| | - Yuguang Zhang
- Department of Plastic and Reconstructive Surgery, Shanghai Ninth People's Hospital Affiliated to Shanghai Jiaotong University of Medicine, Shanghai 200011, China
| | - Wenguo Cui
- Biomaterials Innovation Research Center, Division of Biomedical Engineering, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02139, USA; Department of Orthopedics, The First Affiliated Hospital of Soochow University, Orthopedic Institute, Soochow University, Suzhou, Jiangsu 215006, China.
| | - Nasim Annabi
- Biomaterials Innovation Research Center, Division of Biomedical Engineering, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02139, USA; Department of Chemical Engineering, Northeastern University, Boston, MA 02115, USA.
| | - Ali Khademhosseini
- Biomaterials Innovation Research Center, Division of Biomedical Engineering, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02139, USA; Wyss Institute for Biologically Inspired Engineering, Harvard University, Boston, MA 02115, USA; Department of Physics, King Abdulaziz University, Jeddah 21569, Saudi Arabia.
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517
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Foster AA, Marquardt LM, Heilshorn SC. The Diverse Roles of Hydrogel Mechanics in Injectable Stem Cell Transplantation. Curr Opin Chem Eng 2017; 15:15-23. [PMID: 29085771 PMCID: PMC5659597 DOI: 10.1016/j.coche.2016.11.003] [Citation(s) in RCA: 57] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Stem cell delivery by local injection has tremendous potential as a regenerative therapy but has seen limited clinical success. Several mechanical challenges hinder therapeutic efficacy throughout all stages of cell transplantation, including mechanical forces during injection and loss of mechanical support post-injection. Recent studies have begun exploring the use of biomaterials, in particular hydrogels, to enhance stem cell transplantation by addressing the often-conflicting mechanical requirements associated with each stage of the transplantation process. This review explores recent biomaterial approaches to improve the therapeutic efficacy of stem cells delivered through local injection, with a focus on strategies that specifically address the mechanical challenges that result in cell death and/or limit therapeutic function throughout the stages of transplantation.
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Affiliation(s)
- Abbygail A Foster
- Department of Materials Science and Engineering, Stanford University, Stanford, CA 94305
| | - Laura M Marquardt
- Department of Materials Science and Engineering, Stanford University, Stanford, CA 94305
| | - Sarah C Heilshorn
- Department of Materials Science and Engineering, Stanford University, Stanford, CA 94305
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518
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LIU ZM, YANG Y, DU Y, PANG Y. Advances in Droplet-Based Microfluidic Technology and Its Applications. CHINESE JOURNAL OF ANALYTICAL CHEMISTRY 2017. [DOI: 10.1016/s1872-2040(17)60994-0] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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519
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Han K, Go D, Tigges T, Rahimi K, Kuehne AJC, Walther A. Social Self-Sorting of Colloidal Families in Co-Assembling Microgel Systems. Angew Chem Int Ed Engl 2017. [DOI: 10.1002/ange.201612196] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Affiliation(s)
- Kang Han
- DWI-Leibniz-Institute for Interactive Materials; Forckenbeckstrasse 50 52074 Aachen Germany
| | - Dennis Go
- DWI-Leibniz-Institute for Interactive Materials; Forckenbeckstrasse 50 52074 Aachen Germany
| | - Thomas Tigges
- DWI-Leibniz-Institute for Interactive Materials; Forckenbeckstrasse 50 52074 Aachen Germany
| | - Khosrow Rahimi
- 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
| | - Andreas Walther
- Institute for Macromolecular Chemistry; Albert-Ludwigs-University Freiburg; Stefan-Meier Strasse 31 71096 Freiburg Germany
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520
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Han K, Go D, Tigges T, Rahimi K, Kuehne AJC, Walther A. Social Self-Sorting of Colloidal Families in Co-Assembling Microgel Systems. Angew Chem Int Ed Engl 2017; 56:2176-2182. [DOI: 10.1002/anie.201612196] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2016] [Indexed: 11/08/2022]
Affiliation(s)
- Kang Han
- DWI-Leibniz-Institute for Interactive Materials; Forckenbeckstrasse 50 52074 Aachen Germany
| | - Dennis Go
- DWI-Leibniz-Institute for Interactive Materials; Forckenbeckstrasse 50 52074 Aachen Germany
| | - Thomas Tigges
- DWI-Leibniz-Institute for Interactive Materials; Forckenbeckstrasse 50 52074 Aachen Germany
| | - Khosrow Rahimi
- 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
| | - Andreas Walther
- Institute for Macromolecular Chemistry; Albert-Ludwigs-University Freiburg; Stefan-Meier Strasse 31 71096 Freiburg Germany
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521
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Wang J, Hao S, Luo T, Cheng Z, Li W, Gao F, Guo T, Gong Y, Wang B. Feather keratin hydrogel for wound repair: Preparation, healing effect and biocompatibility evaluation. Colloids Surf B Biointerfaces 2017; 149:341-350. [DOI: 10.1016/j.colsurfb.2016.10.038] [Citation(s) in RCA: 86] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2016] [Revised: 10/17/2016] [Accepted: 10/21/2016] [Indexed: 12/20/2022]
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522
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Foster GA, Headen DM, González-García C, Salmerón-Sánchez M, Shirwan H, García AJ. Protease-degradable microgels for protein delivery for vascularization. Biomaterials 2017; 113:170-175. [PMID: 27816000 PMCID: PMC5121008 DOI: 10.1016/j.biomaterials.2016.10.044] [Citation(s) in RCA: 59] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2016] [Revised: 10/19/2016] [Accepted: 10/27/2016] [Indexed: 12/16/2022]
Abstract
Degradable hydrogels to deliver bioactive proteins represent an emerging platform for promoting tissue repair and vascularization in various applications. However, implanting these biomaterials requires invasive surgery, which is associated with complications such as inflammation, scarring, and infection. To address these shortcomings, we applied microfluidics-based polymerization to engineer injectable poly(ethylene glycol) microgels of defined size and crosslinked with a protease degradable peptide to allow for triggered release of proteins. The release rate of proteins covalently tethered within the microgel network was tuned by modifying the ratio of degradable to non-degradable crosslinkers, and the released proteins retained full bioactivity. Microgels injected into the dorsum of mice were maintained in the subcutaneous space and degraded within 2 weeks in response to local proteases. Furthermore, controlled release of VEGF from degradable microgels promoted increased vascularization compared to empty microgels or bolus injection of VEGF. Collectively, this study motivates the use of microgels as a viable method for controlled protein delivery in regenerative medicine applications.
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Affiliation(s)
- Greg A Foster
- Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA, USA; Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, GA, USA
| | - Devon M Headen
- Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA, USA; Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, GA, USA
| | - Cristina González-García
- Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA, USA; Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, GA, USA; School of Engineering, Division of Biomedical Engineering, University of Glasgow, Glasgow, Scotland, UK
| | - Manuel Salmerón-Sánchez
- Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA, USA; Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, GA, USA; School of Engineering, Division of Biomedical Engineering, University of Glasgow, Glasgow, Scotland, UK
| | - Haval Shirwan
- Department of Microbiology and Immunology, University of Louisville, Louisville, KY, USA
| | - Andrés J García
- Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA, USA; Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, GA, USA.
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523
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Zhu S, Wang J, Yan H, Wang Y, Zhao Y, Feng B, Duan K, Weng J. An injectable supramolecular self-healing bio-hydrogel with high stretchability, extensibility and ductility, and a high swelling ratio. J Mater Chem B 2017; 5:7021-7034. [DOI: 10.1039/c7tb01183k] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Reversible networks are a key factor for designing self-healing hydrogels with high stretching properties.
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Affiliation(s)
- Shukai Zhu
- Key Laboratory of Advance Technologies of Materials
- Ministry of Education
- School of Materials Science and Engineering
- Southwest Jiaotong University
- Chengdu 610031
| | - Jianxin Wang
- Key Laboratory of Advance Technologies of Materials
- Ministry of Education
- School of Materials Science and Engineering
- Southwest Jiaotong University
- Chengdu 610031
| | - Haoran Yan
- Key Laboratory of Advance Technologies of Materials
- Ministry of Education
- School of Materials Science and Engineering
- Southwest Jiaotong University
- Chengdu 610031
| | - Yingying Wang
- Key Laboratory of Advance Technologies of Materials
- Ministry of Education
- School of Materials Science and Engineering
- Southwest Jiaotong University
- Chengdu 610031
| | - Yuancong Zhao
- Key Laboratory of Advance Technologies of Materials
- Ministry of Education
- School of Materials Science and Engineering
- Southwest Jiaotong University
- Chengdu 610031
| | - Bo Feng
- Key Laboratory of Advance Technologies of Materials
- Ministry of Education
- School of Materials Science and Engineering
- Southwest Jiaotong University
- Chengdu 610031
| | - Ke Duan
- Key Laboratory of Advance Technologies of Materials
- Ministry of Education
- School of Materials Science and Engineering
- Southwest Jiaotong University
- Chengdu 610031
| | - Jie Weng
- Key Laboratory of Advance Technologies of Materials
- Ministry of Education
- School of Materials Science and Engineering
- Southwest Jiaotong University
- Chengdu 610031
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524
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Chen Y, Huang L, Dai X, Tian Q, Yu M, Agheb M, Chan HN, Poon E, Guo Z, Boheler KR, Wu H. Facile formation of a microporous chitosan hydrogel based on self-crosslinking. J Mater Chem B 2017; 5:9291-9299. [DOI: 10.1039/c7tb02736b] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A facile approach for the formation of microporous (chitosan) hydrogel scaffolds based on self-crosslinking is presented. It is simple and does not require any sacrificial porogen, toxic initiator/catalyst, harmful irradiation, or sophisticated equipment.
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Affiliation(s)
- Yin Chen
- Division of Biomedical Engineering
- The Hong Kong University of Science and Technology
- China
| | - Lu Huang
- Department of Chemistry
- The Hong Kong University of Science and Technology
- China
| | - Xin Dai
- Department of Chemistry
- The Hong Kong University of Science and Technology
- China
| | - Qian Tian
- Department of Chemistry
- The Hong Kong University of Science and Technology
- China
| | - Miao Yu
- Department of Mechanical and Aerospace Engineering
- The Hong Kong University of Science and Technology
- China
| | - Maria Agheb
- Department of Chemistry
- The Hong Kong University of Science and Technology
- China
| | - Ho Nam Chan
- Department of Chemistry
- The Hong Kong University of Science and Technology
- China
| | - Ellen Poon
- Stem Cell and Regenerative Medicine Consortium
- Li Ka Shing Faculty of Medicine
- The University of Hong Kong
- China
| | - Zhihong Guo
- Department of Chemistry
- The Hong Kong University of Science and Technology
- China
| | - Kenneth Richard Boheler
- Stem Cell and Regenerative Medicine Consortium
- Li Ka Shing Faculty of Medicine
- The University of Hong Kong
- China
| | - Hongkai Wu
- Division of Biomedical Engineering
- The Hong Kong University of Science and Technology
- China
- Department of Chemistry
- The Hong Kong University of Science and Technology
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525
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Hu J, Chen Y, Li Y, Zhou Z, Cheng Y. A thermo-degradable hydrogel with light-tunable degradation and drug release. Biomaterials 2017; 112:133-140. [DOI: 10.1016/j.biomaterials.2016.10.015] [Citation(s) in RCA: 71] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2016] [Revised: 10/10/2016] [Accepted: 10/11/2016] [Indexed: 12/14/2022]
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526
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Singh Chandel AK, Kannan D, Nutan B, Singh S, Jewrajka SK. Dually crosslinked injectable hydrogels of poly(ethylene glycol) and poly[(2-dimethylamino)ethyl methacrylate]-b-poly(N-isopropyl acrylamide) as a wound healing promoter. J Mater Chem B 2017; 5:4955-4965. [DOI: 10.1039/c7tb00848a] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
PEG-based dually crosslinked injectable hydrogels have been developed through extremely simple chemistry which avoids use of small molecular weight crosslinker, formation of by-products and involved low heat change. The hydrogels are useful for wound healing and soft tissue regeneration.
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Affiliation(s)
- Arvind K. Singh Chandel
- Reverse Osmosis Membrane Division
- academy of Scientific and Innovative Research
- CSIR-Central Salt and Marine Chemicals Research Institute G. B. Marg
- Bhavnagar
- India
| | - Deepika Kannan
- Department of Life Science
- Shiv Nadar University
- India
- Special Centre for Molecular Medicine
- Jawaharlal Nehru University
| | - Bhingaradiya Nutan
- Reverse Osmosis Membrane Division
- academy of Scientific and Innovative Research
- CSIR-Central Salt and Marine Chemicals Research Institute G. B. Marg
- Bhavnagar
- India
| | - Shailja Singh
- Department of Life Science
- Shiv Nadar University
- India
- Special Centre for Molecular Medicine
- Jawaharlal Nehru University
| | - Suresh K. Jewrajka
- Reverse Osmosis Membrane Division
- academy of Scientific and Innovative Research
- CSIR-Central Salt and Marine Chemicals Research Institute G. B. Marg
- Bhavnagar
- India
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527
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Frueh FS, Später T, Lindenblatt N, Calcagni M, Giovanoli P, Scheuer C, Menger MD, Laschke MW. Adipose Tissue-Derived Microvascular Fragments Improve Vascularization, Lymphangiogenesis, and Integration of Dermal Skin Substitutes. J Invest Dermatol 2017; 137:217-227. [DOI: 10.1016/j.jid.2016.08.010] [Citation(s) in RCA: 52] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2016] [Revised: 08/01/2016] [Accepted: 08/15/2016] [Indexed: 01/08/2023]
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528
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Staruch RMT, Glass GE, Rickard R, Hettiaratchy SP, Butler PEM. Injectable Pore-Forming Hydrogel Scaffolds for Complex Wound Tissue Engineering: Designing and Controlling Their Porosity and Mechanical Properties. TISSUE ENGINEERING PART B-REVIEWS 2016; 23:183-198. [PMID: 27824295 DOI: 10.1089/ten.teb.2016.0305] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Traumatic soft tissue wounds present a significant reconstructive challenge. The adoption of closed-circuit negative pressure wound therapy (NPWT) has enabled surgeons to temporize these wounds before reconstruction. Such systems use porous synthetic foam scaffolds as wound fillers at the interface between the negative pressure system and the wound bed. The idea of using a bespoke porous biomaterial that enhances wound healing, as filler for an NPWT system, is attractive as it circumvents concerns regarding reconstructive delay and the need for dressing changes that are features of the current systems. Porous foam biomaterials are mechanically robust and able to synthesize in situ. Hence, they exhibit potential to fulfill the niche for such a functionalized injectable material. Injectable scaffolds are currently in use for minimally invasive surgery, but the design parameters for large-volume expansive foams remain unclear. Potential platforms include hydrogel systems, (particularly superabsorbent, superporous, and nanocomposite systems), polyurethane-based moisture-cured foams, and high internal phase emulsion polymer systems. The aim of this review is to discuss the design parameters for such future biomaterials and review potential candidate materials for further research into this up and coming field.
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Affiliation(s)
- Robert M T Staruch
- 1 School of Engineering and Applied Sciences, Harvard University , Cambridge, Massachusetts
| | - Graeme E Glass
- 2 Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Science, University of Oxford , Oxford, United Kingdom
| | - Rory Rickard
- 3 Academic Department of Military Surgery and Trauma , ICT Business Park, Birmingham, United Kingdom
| | | | - Peter E M Butler
- 5 Department of Surgery and Interventional Sciences, The Royal Free Hospital, University College London , London, United Kingdom
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529
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2016 TERMIS - Americas Conference and Exhibition San Diego, CA December 11-14, 2016. Tissue Eng Part A 2016; 22:S1-S156. [PMID: 27935743 DOI: 10.1089/ten.tea.2016.5000.abstracts] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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530
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Abstract
Hydrogel delivery systems can leverage therapeutically beneficial outcomes of drug delivery and have found clinical use. Hydrogels can provide spatial and temporal control over the release of various therapeutic agents, including small-molecule drugs, macromolecular drugs and cells. Owing to their tunable physical properties, controllable degradability and capability to protect labile drugs from degradation, hydrogels serve as a platform in which various physiochemical interactions with the encapsulated drugs control their release. In this Review, we cover multiscale mechanisms underlying the design of hydrogel drug delivery systems, focusing on physical and chemical properties of the hydrogel network and the hydrogel-drug interactions across the network, mesh, and molecular (or atomistic) scales. We discuss how different mechanisms interact and can be integrated to exert fine control in time and space over the drug presentation. We also collect experimental release data from the literature, review clinical translation to date of these systems, and present quantitative comparisons between different systems to provide guidelines for the rational design of hydrogel delivery systems.
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Affiliation(s)
- Jianyu Li
- John A. Paulson School of Engineering and Applied Sciences, and the Wyss Institute for biologically Inspired Engineering, Harvard University, Cambridge, Massachusetts 02138, USA
| | - David J Mooney
- John A. Paulson School of Engineering and Applied Sciences, and the Wyss Institute for biologically Inspired Engineering, Harvard University, Cambridge, Massachusetts 02138, USA
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531
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Yu J, Huang TR, Lim ZH, Luo R, Pasula RR, Liao LD, Lim S, Chen CH. Production of Hollow Bacterial Cellulose Microspheres Using Microfluidics to Form an Injectable Porous Scaffold for Wound Healing. Adv Healthc Mater 2016; 5:2983-2992. [PMID: 27805793 DOI: 10.1002/adhm.201600898] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2016] [Revised: 09/15/2016] [Indexed: 12/20/2022]
Abstract
Bacterial cellulose (BC) is a biocompatible material with high purity and robust mechanical strength used to fabricate desirable scaffolds for 3D cell culture and wound healing. However, the chemical resistance of BC and its insolubility in the majority of solutions make it difficult to manipulate using standard chemical methods. In this study, a microfluidic process is developed to produce hollow BC microspheres with desirable internal structures and morphology. Microfluidics is used to generate a core-shell structured microparticle with an alginate core and agarose shell as a template to encapsulate Gluconacetobacter xylinus for long-term static culture. G. xylinus then secretes BC, which becomes entangled within the shell of the structured hydrogel microparticles and forms BC microspheres. The removal of the hydrogel template via thermal-chemical treatments yields robust BC microspheres exhibiting a hollow morphology. These hollow microspheres spontaneously assemble as functional units to form a novel injectable scaffold. In vitro, a highly porous scaffold is created to enable effective 3D cell culture with a high cell proliferation rate and better depth distribution. In vivo, this injectable scaffold facilitates tissue regeneration, resulting in rapid wound-healing in a Sprague Dawley rat skin model.
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Affiliation(s)
- Jiaqing Yu
- Department of Biomedical Engineering; National University of Singapore; 9 Engineering Drive 1 117575 Singapore
| | - Tzu-Rung Huang
- Singapore Institute for Neurotechnology; 28 Medical Drive, #05-COR 117456 Singapore
| | - Zhen Han Lim
- Department of Biomedical Engineering; National University of Singapore; 9 Engineering Drive 1 117575 Singapore
| | - Rongcong Luo
- Department of Biomedical Engineering; National University of Singapore; 9 Engineering Drive 1 117575 Singapore
| | - Rupali Reddy Pasula
- Division of Bioengineering; School of Chemical and Biomedical Engineering; College of Engineering; Nanyang Technological University; 62 Nanyang Drive 637459 Singapore
| | - Lun-De Liao
- Singapore Institute for Neurotechnology; 28 Medical Drive, #05-COR 117456 Singapore
- Institute of Biomedical Engineering and Nanomedicine, National Health Research Institutes; 35 Keyan Road, Zhunan Town, Miaoli County 35053 Taiwan
| | - Sierin Lim
- Division of Bioengineering; School of Chemical and Biomedical Engineering; College of Engineering; Nanyang Technological University; 62 Nanyang Drive 637459 Singapore
| | - Chia-Hung Chen
- Department of Biomedical Engineering; National University of Singapore; 9 Engineering Drive 1 117575 Singapore
- Singapore Institute for Neurotechnology; 28 Medical Drive, #05-COR 117456 Singapore
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532
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Jiang W, Li M, Chen Z, Leong KW. Cell-laden microfluidic microgels for tissue regeneration. LAB ON A CHIP 2016; 16:4482-4506. [PMID: 27797383 PMCID: PMC5110393 DOI: 10.1039/c6lc01193d] [Citation(s) in RCA: 108] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
Regeneration of diseased tissue is one of the foremost concerns for millions of patients who suffer from tissue damage each year. Local delivery of cell-laden hydrogels offers an attractive approach for tissue repair. However, due to the typical macroscopic size of these cell constructs, the encapsulated cells often suffer from poor nutrient exchange. These issues can be mitigated by incorporating cells into microscopic hydrogels, or microgels, whose large surface-to-volume ratio promotes efficient mass transport and enhanced cell-matrix interactions. Using microfluidic technology, monodisperse cell-laden microgels with tunable sizes can be generated in a high-throughput manner, making them useful building blocks that can be assembled into tissue constructs with spatially controlled physicochemical properties. In this review, we examine microfluidics-generated cell-laden microgels for tissue regeneration applications. We provide a brief overview of the common biomaterials, gelation mechanisms, and microfluidic device designs that are used to generate these microgels, and summarize the most recent works on how they are applied to tissue regeneration. Finally, we discuss future applications of microfluidic cell-laden microgels as well as existing challenges that should be resolved to stimulate their clinical application.
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Affiliation(s)
- Weiqian Jiang
- Department of Biomedical Engineering, Columbia University, New York, NY 10027, USA.
| | - Mingqiang Li
- Department of Biomedical Engineering, Columbia University, New York, NY 10027, USA.
| | - Zaozao Chen
- Department of Biomedical Engineering, Columbia University, New York, NY 10027, USA.
| | - Kam W Leong
- Department of Biomedical Engineering, Columbia University, New York, NY 10027, USA.
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533
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Später T, Frueh FS, Metzger W, Menger MD, Laschke MW. In vivo
biocompatibility, vascularization, and incorporation of Integra®
dermal regenerative template and flowable wound matrix. J Biomed Mater Res B Appl Biomater 2016; 106:52-60. [DOI: 10.1002/jbm.b.33813] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2016] [Revised: 10/05/2016] [Accepted: 10/27/2016] [Indexed: 12/24/2022]
Affiliation(s)
- Thomas Später
- Institute for Clinical & Experimental Surgery, Saarland University; 66421 Homburg/Saar Germany
| | - Florian S. Frueh
- Institute for Clinical & Experimental Surgery, Saarland University; 66421 Homburg/Saar Germany
- Division of Plastic Surgery and Hand Surgery; University Hospital Zurich; 8091 Zurich Switzerland
| | - Wolfgang Metzger
- Department of Trauma, Hand and Reconstructive Surgery; Saarland University; 66421 Homburg/Saar Germany
| | - Michael D. Menger
- Institute for Clinical & Experimental Surgery, Saarland University; 66421 Homburg/Saar Germany
| | - Matthias W. Laschke
- Institute for Clinical & Experimental Surgery, Saarland University; 66421 Homburg/Saar Germany
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534
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Hybrid Nanostructures Containing Sulfadiazine Modified Chitosan as Antimicrobial Drug Carriers. NANOMATERIALS 2016; 6:nano6110207. [PMID: 28335334 PMCID: PMC5245742 DOI: 10.3390/nano6110207] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/24/2016] [Revised: 11/03/2016] [Accepted: 11/04/2016] [Indexed: 12/11/2022]
Abstract
Chitosan (CH) nanofibrous structures containing sulfadiazine (SDZ) or sulfadiazine modified chitosan (SCH) in the form of functional nanoparticles attached to nanofibers (hybrid nanostructures) were obtained by mono-axial and coaxial electrospinning. The mono-axial design consisted of a SDZ/CH mixture solution fed through a single nozzle while the coaxial design consisted of SCH and CH solutions separately supplied to the inner and outer nozzle (or in reverse order). The CH ability to form nanofibers assured the formation of a nanofiber mesh, while SDZ and SCH, both in form of suspensions in the electrospun solution, assured the formation of active nanoparticles which remained attached to the CH nanofiber mesh after the electrospinning process. The obtained nanostructures were morphologically characterized by scanning electron microscopy (SEM) and atomic force microscopy (AFM). The SDZ release profiles and kinetics were analyzed. The SDZ or SCH nanoparticles loosely attached at the surface of the nanofibers, provide a burst release in the first 20 min, which is important to stop the possible initial infection in a wound, while the SDZ and SCH from the nanoparticles which are better confined (or even encapsulated) into the CH nanofibers would be slowly released with the erosion/disruption of the CH nanofiber mesh.
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535
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Riederer MS, Requist BD, Payne KA, Way JD, Krebs MD. Injectable and microporous scaffold of densely-packed, growth factor-encapsulating chitosan microgels. Carbohydr Polym 2016; 152:792-801. [PMID: 27516331 PMCID: PMC4988396 DOI: 10.1016/j.carbpol.2016.07.052] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2016] [Revised: 07/12/2016] [Accepted: 07/14/2016] [Indexed: 12/20/2022]
Abstract
In this work, an emulsion crosslinking method was developed to produce chitosan-genipin microgels which acted as an injectable and microporous scaffold. Chitosan was characterized with respect to pH by light scattering and aqueous titration. Microgels were characterized with swelling, light scattering, and rheometry of densely-packed microgel solutions. The results suggest that as chitosan becomes increasingly deprotonated above the pKa, repulsive forces diminish and intermolecular attractions cause pH-responsive chain aggregation; leading to microgel-microgel aggregation as well. The microgels with the most chitosan and least cross-linker showed the highest yield stress and a storage modulus of 16kPa when condensed as a microgel paste at pH 7.4. Two oppositely-charged growth factors could be encapsulated into the microgels and endothelial cells were able to proliferate into the 3D microgel scaffold. This work motivates further research on the applications of the chitosan microgel scaffold as an injectable and microporous scaffold in regenerative medicine.
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Affiliation(s)
- Michael S Riederer
- Department of Chemical & Biological Engineering, Colorado School of Mines, 1613 Illinois Street, Golden, CO 80401, United States.
| | - Brennan D Requist
- Department of Chemical & Biological Engineering, Colorado School of Mines, 1613 Illinois Street, Golden, CO 80401, United States.
| | - Karin A Payne
- Department of Orthopedics, University of Colorado Anschutz Medical Campus, 12800 E. 19th Avenue, Aurora, CO 80045, United States.
| | - J Douglas Way
- Department of Chemical & Biological Engineering, Colorado School of Mines, 1613 Illinois Street, Golden, CO 80401, United States.
| | - Melissa D Krebs
- Department of Chemical & Biological Engineering, Colorado School of Mines, 1613 Illinois Street, Golden, CO 80401, United States.
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536
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Das S, Baker AB. Biomaterials and Nanotherapeutics for Enhancing Skin Wound Healing. Front Bioeng Biotechnol 2016; 4:82. [PMID: 27843895 PMCID: PMC5087310 DOI: 10.3389/fbioe.2016.00082] [Citation(s) in RCA: 155] [Impact Index Per Article: 19.4] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2016] [Accepted: 10/11/2016] [Indexed: 02/06/2023] Open
Abstract
Wound healing is an intricate process that requires complex coordination between many cell types and an appropriate extracellular microenvironment. Chronic wounds often suffer from high protease activity, persistent infection, excess inflammation, and hypoxia. While there has been intense investigation to find new methods to improve cutaneous wound care, the management of chronic wounds, burns, and skin wound infection remain challenging clinical problems. Ideally, advanced wound dressings can provide enhanced healing and bridge the gaps in the healing processes that prevent chronic wounds from healing. These technologies have great potential for improving outcomes in patients with poorly healing wounds but face significant barriers in addressing the heterogeneity and clinical complexity of chronic or severe wounds. Active wound dressings aim to enhance the natural healing process and work to counter many aspects that plague poorly healing wounds, including excessive inflammation, ischemia, scarring, and wound infection. This review paper discusses recent advances in the development of biomaterials and nanoparticle therapeutics to enhance wound healing. In particular, this review focuses on the novel cutaneous wound treatments that have undergone significant preclinical development or are currently used in clinical practice.
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Affiliation(s)
- Subhamoy Das
- Department of Biomedical Engineering, University of Texas at Austin , Austin, TX , USA
| | - Aaron B Baker
- Department of Biomedical Engineering, University of Texas at Austin, Austin, TX, USA; Institute for Biomaterials, Drug Delivery and Regenerative Medicine, University of Texas at Austin, Austin, TX, USA; Institute for Cellular and Molecular Biology, University of Texas at Austin, Austin, TX, USA; Institute for Computational Engineering and Sciences, University of Texas at Austin, Austin, TX, USA
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537
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Jivan F, Yegappan R, Pearce H, Carrow JK, McShane M, Gaharwar AK, Alge DL. Sequential Thiol–Ene and Tetrazine Click Reactions for the Polymerization and Functionalization of Hydrogel Microparticles. Biomacromolecules 2016; 17:3516-3523. [DOI: 10.1021/acs.biomac.6b00990] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Affiliation(s)
- Faraz Jivan
- Department of Biomedical Engineering, ‡Department of Materials Science and Engineering, and §Center for Remote Health Technologies and Systems, Texas A&M University, College Station, Texas 77843, United States
| | - Ramanathan Yegappan
- Department of Biomedical Engineering, ‡Department of Materials Science and Engineering, and §Center for Remote Health Technologies and Systems, Texas A&M University, College Station, Texas 77843, United States
| | - Hannah Pearce
- Department of Biomedical Engineering, ‡Department of Materials Science and Engineering, and §Center for Remote Health Technologies and Systems, Texas A&M University, College Station, Texas 77843, United States
| | - James K. Carrow
- Department of Biomedical Engineering, ‡Department of Materials Science and Engineering, and §Center for Remote Health Technologies and Systems, Texas A&M University, College Station, Texas 77843, United States
| | - Michael McShane
- Department of Biomedical Engineering, ‡Department of Materials Science and Engineering, and §Center for Remote Health Technologies and Systems, Texas A&M University, College Station, Texas 77843, United States
| | - Akhilesh K. Gaharwar
- Department of Biomedical Engineering, ‡Department of Materials Science and Engineering, and §Center for Remote Health Technologies and Systems, Texas A&M University, College Station, Texas 77843, United States
| | - Daniel L. Alge
- Department of Biomedical Engineering, ‡Department of Materials Science and Engineering, and §Center for Remote Health Technologies and Systems, Texas A&M University, College Station, Texas 77843, United States
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538
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Khaing ZZ, Ehsanipour A, Hofstetter CP, Seidlits SK. Injectable Hydrogels for Spinal Cord Repair: A Focus on Swelling and Intraspinal Pressure. Cells Tissues Organs 2016; 202:67-84. [DOI: 10.1159/000446697] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/10/2016] [Indexed: 11/19/2022] Open
Abstract
Spinal cord injury (SCI) is a devastating condition that leaves patients with limited motor and sensory function at and below the injury site, with little to no hope of a meaningful recovery. Because of their ability to mimic multiple features of central nervous system (CNS) tissues, injectable hydrogels are being developed that can participate as therapeutic agents in reducing secondary injury and in the regeneration of spinal cord tissue. Injectable biomaterials can provide a supportive substrate for tissue regeneration, deliver therapeutic factors, and regulate local tissue physiology. Recent reports of increasing intraspinal pressure after SCI suggest that this physiological change can contribute to injury expansion, also known as secondary injury. Hydrogels contain high water content similar to native tissue, and many hydrogels absorb water and swell after formation. In the case of injectable hydrogels for the spinal cord, this process often occurs in or around the spinal cord tissue, and thus may affect intraspinal pressure. In the future, predictable swelling properties of hydrogels may be leveraged to control intraspinal pressure after injury. Here, we review the physiology of SCI, with special attention to the current clinical and experimental literature, underscoring the importance of controlling intraspinal pressure after SCI. We then discuss how hydrogel fabrication, injection, and swelling can impact intraspinal pressure in the context of developing injectable biomaterials for SCI treatment.
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539
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Latxague L, Gaubert A, Maleville D, Baillet J, Ramin MA, Barthélémy P. Carbamate-Based Bolaamphiphile as Low-Molecular-Weight Hydrogelators. Gels 2016; 2:gels2040025. [PMID: 30674156 PMCID: PMC6318576 DOI: 10.3390/gels2040025] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2016] [Revised: 09/21/2016] [Accepted: 09/22/2016] [Indexed: 11/16/2022] Open
Abstract
A new bolaamphiphile analog featuring carbamate moieties was synthesized in six steps starting from thymidine. The amphiphile structure exhibits nucleoside-sugar polar heads attached to a hydrophobic spacer via carbamate (urethane) functions. This molecular structure, which possesses additional H-bonding capabilities, induces the stabilization of low-molecular-weight gels (LMWGs) in water. The rheological studies revealed that the new bolaamphiphile 7 stabilizes thixotropic hydrogels with a high elastic modulus (G′ > 50 kPa).
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Affiliation(s)
- Laurent Latxague
- ARNA laboratory, Univ. Bordeaux, ChemBioPharm, INSERM, U1212, CNRS UMR 5320, F-33000 Bordeaux, France.
| | - Alexandra Gaubert
- ARNA laboratory, Univ. Bordeaux, ChemBioPharm, INSERM, U1212, CNRS UMR 5320, F-33000 Bordeaux, France.
| | - David Maleville
- ARNA laboratory, Univ. Bordeaux, ChemBioPharm, INSERM, U1212, CNRS UMR 5320, F-33000 Bordeaux, France.
| | - Julie Baillet
- ARNA laboratory, Univ. Bordeaux, ChemBioPharm, INSERM, U1212, CNRS UMR 5320, F-33000 Bordeaux, France.
| | - Michael A Ramin
- ARNA laboratory, Univ. Bordeaux, ChemBioPharm, INSERM, U1212, CNRS UMR 5320, F-33000 Bordeaux, France.
| | - Philippe Barthélémy
- ARNA laboratory, Univ. Bordeaux, ChemBioPharm, INSERM, U1212, CNRS UMR 5320, F-33000 Bordeaux, France.
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540
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Sideris E, Griffin DR, Ding Y, Li S, Weaver WM, Di Carlo D, Hsiai T, Segura T. Particle Hydrogels Based on Hyaluronic Acid Building Blocks. ACS Biomater Sci Eng 2016; 2:2034-2041. [PMID: 33440539 DOI: 10.1021/acsbiomaterials.6b00444] [Citation(s) in RCA: 90] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
The extracellular matrix (ECM) provides tissues with the mechanical support, space, and bioactive signals needed for homeostasis or tissue repair after wounding or disease. Hydrogel based scaffolds that can match the bulk mechanical properties of the target tissue have been extensively explored as ECM mimics. Although the addition of microporosity to hydrogel scaffolds has been shown to enhance cell/tissue-material integration, the introduction of microporosity often involves harsh chemical methods, which limit bioactive signal incorporation and injectability. Particle hydrogels are an emerging platform to generate in situ forming microporous scaffolds. In this approach, μgel particles are annealed to each other to form a bulk scaffold that is porous because of the void space left by the packed microgels. In the present work, we discuss the formation of hyaluronic acid-based microfluidic generated microgels for the generation of a completely biodegradable material. The generation of particle scaffolds requires two orthogonal chemistries, one for microgel generation and one for microgel annealing and scaffold formation. Here we explore three orthogonal annealing chemistries based on an enzymatic reaction, light based radical polymerization, and amine/carboxylic acid based cross-linking to demonstrate the versatility of our particle hydrogels and explore potential physical differences between the approaches. We explore the connectivity of the generated pores, the pore area/void fraction of the resulting scaffold, the mechanical properties of the scaffold, and cell spreading within scaffolds formed with the three different annealing mechanisms.
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Affiliation(s)
| | | | - Yichen Ding
- Division of Cardiology, Department of Medicine, University of California Los Angeles, 10833 Le Conte Avenue, Los Angeles, California 90095, United States
| | | | | | | | - Tzung Hsiai
- Division of Cardiology, Department of Medicine, University of California Los Angeles, 10833 Le Conte Avenue, Los Angeles, California 90095, United States
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541
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Sharma V, Patel N, Kohli N, Ravindran N, Hook L, Mason C, García-Gareta E. Viscoelastic, physical, and bio-degradable properties of dermal scaffolds and related cell behaviour. ACTA ACUST UNITED AC 2016; 11:055001. [PMID: 27586397 DOI: 10.1088/1748-6041/11/5/055001] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Dermal scaffolds promote healing of debilitating skin injuries caused by burns and chronic skin conditions. Currently available products present disadvantages and therefore, there is still a clinical need for developing new dermal substitutes. This study aimed at comparing the viscoelastic, physical and bio-degradable properties of two dermal scaffolds, the collagen-based and clinically well established Integra(®) and a novel fibrin-based dermal scaffold developed at our laboratory called Smart Matrix(®), to further evaluate our previous published findings that suggested a higher influx of cells, reduced wound contraction and less scarring for Smart Matrix(®) when used in vivo. Rheological results showed that Integra(®) (G' = 313.74 kPa) is mechanically stronger than Smart Matrix(®) (G' = 8.26 kPa), due to the presence of the silicone backing layer in Integra(®). Micro-pores were observed on both dermal scaffolds, although nano-pores as well as densely packed nano-fibres were only observed for Smart Matrix(®). Average surface roughness was higher for Smart Matrix(®) (Sa = 114.776 nm) than for Integra(®) (Sa = 75.565 nm). Both scaffolds possess a highly porous structure (80-90%) and display a range of pore micro-sizes that represent the actual in vivo scenario. In vitro proteolytic bio-degradation suggested that Smart Matrix(®) would degrade faster upon implantation in vivo than Integra(®). For both scaffolds, the enzymatic digestion occurs via bulk degradation. These observed differences could affect cell behaviour on both scaffolds. Our results suggest that fine-tuning of scaffolds' viscoelastic, physical and bio-degradable properties can maximise cell behaviour in terms of attachment, proliferation and infiltration, which are essential for tissue repair.
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Affiliation(s)
- Vaibhav Sharma
- RAFT Institute of Plastic Surgery, Mount Vernon Hospital, Northwood, HA6 2RN, UK. Department of Biochemical Engineering, University College London, Gower Street, London, WC1E 6BT, UK
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542
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Kim BY, Lee Y, Son JY, Park KM, Park KD. Dual Enzyme-Triggered In Situ Crosslinkable Gelatin Hydrogels for Artificial Cellular Microenvironments. Macromol Biosci 2016; 16:1570-1576. [DOI: 10.1002/mabi.201600312] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2016] [Revised: 08/02/2016] [Indexed: 12/21/2022]
Affiliation(s)
- Bae Young Kim
- Department of Molecular Science and Technology; Ajou University; 206 Worldcup-ro Yeontong-gu Suwon 16499 South Korea
| | - Yunki Lee
- Department of Molecular Science and Technology; Ajou University; 206 Worldcup-ro Yeontong-gu Suwon 16499 South Korea
| | - Joo Young Son
- Department of Molecular Science and Technology; Ajou University; 206 Worldcup-ro Yeontong-gu Suwon 16499 South Korea
| | - Kyung Min Park
- Division of Bioengineering; College of Life Sciences and Bioengineering; Incheon National University; 119 Academy-ro Yeonsu-gu Incheon 22012 South Korea
| | - Ki Dong Park
- Department of Molecular Science and Technology; Ajou University; 206 Worldcup-ro Yeontong-gu Suwon 16499 South Korea
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543
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Conchouso D, McKerricher G, Arevalo A, Castro D, Shamim A, Foulds IG. Comparison of capacitive and radio frequency resonator sensors for monitoring parallelized droplet microfluidic production. LAB ON A CHIP 2016; 16:3210-3219. [PMID: 27381892 DOI: 10.1039/c6lc00693k] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Scaled-up production of microfluidic droplets, through the parallelization of hundreds of droplet generators, has received a lot of attention to bring novel multiphase microfluidics research to industrial applications. However, apart from droplet generation, other significant challenges relevant to this goal have never been discussed. Examples include monitoring systems, high-throughput processing of droplets and quality control procedures among others. In this paper, we present and compare capacitive and radio frequency (RF) resonator sensors as two candidates that can measure the dielectric properties of emulsions in microfluidic channels. By placing several of these sensors in a parallelization device, the stability of the droplet generation at different locations can be compared, and potential malfunctions can be detected. This strategy enables for the first time the monitoring of scaled-up microfluidic droplet production. Both sensors were prototyped and characterized using emulsions with droplets of 100-150 μm in diameter, which were generated in parallelization devices at water-in-oil volume fractions (φ) between 11.1% and 33.3%.Using these sensors, we were able to measure accurately increments as small as 2.4% in the water volume fraction of the emulsions. Although both methods rely on the dielectric properties of the emulsions, the main advantage of the RF resonator sensors is the fact that they can be designed to resonate at multiple frequencies of the broadband transmission line. Consequently with careful design, two or more sensors can be parallelized and read out by a single signal. Finally, a comparison between these sensors based on their sensitivity, readout cost and simplicity, and design flexibility is also discussed.
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Affiliation(s)
- David Conchouso
- Electromechanical Microsystems and Polymer Integration Research Laboratory (EMPIRe Lab), at the Computer, Electrical, and Mathematical Sciences and Engineering Division, King Abdullah University of Science and Technology, 4700 KAUST, 23955 Thuwal, Kingdom of Saudi Arabia.
| | - Garret McKerricher
- Integrated Microwave Packaging Antennas and Circuits Technology (IMPACT), at the Computer, Electrical, and Mathematical Sciences and Engineering Division, King Abdullah University of Science and Technology, 4700 KAUST, 23955 Thuwal, Kingdom of Saudi Arabia
| | - Arpys Arevalo
- Electromechanical Microsystems and Polymer Integration Research Laboratory (EMPIRe Lab), at the Computer, Electrical, and Mathematical Sciences and Engineering Division, King Abdullah University of Science and Technology, 4700 KAUST, 23955 Thuwal, Kingdom of Saudi Arabia.
| | - David Castro
- Electromechanical Microsystems and Polymer Integration Research Laboratory (EMPIRe Lab), at the Computer, Electrical, and Mathematical Sciences and Engineering Division, King Abdullah University of Science and Technology, 4700 KAUST, 23955 Thuwal, Kingdom of Saudi Arabia.
| | - Atif Shamim
- Integrated Microwave Packaging Antennas and Circuits Technology (IMPACT), at the Computer, Electrical, and Mathematical Sciences and Engineering Division, King Abdullah University of Science and Technology, 4700 KAUST, 23955 Thuwal, Kingdom of Saudi Arabia
| | - Ian G Foulds
- Electromechanical Microsystems and Polymer Integration Research Laboratory (EMPIRe Lab), at the Computer, Electrical, and Mathematical Sciences and Engineering Division, King Abdullah University of Science and Technology, 4700 KAUST, 23955 Thuwal, Kingdom of Saudi Arabia. and University of British Columbia, Okanagan, Canada
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544
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545
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Frueh FS, Menger MD, Lindenblatt N, Giovanoli P, Laschke MW. Current and emerging vascularization strategies in skin tissue engineering. Crit Rev Biotechnol 2016; 37:613-625. [PMID: 27439727 DOI: 10.1080/07388551.2016.1209157] [Citation(s) in RCA: 88] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Vascularization is a key process in skin tissue engineering, determining the biological function of artificial skin implants. Hence, efficient vascularization strategies are a major prerequisite for the safe application of these implants in clinical practice. Current approaches include (i) modification of structural and physicochemical properties of dermal scaffolds, (ii) biological scaffold activation with growth factor-releasing systems or gene vectors, and (iii) generation of prevascularized skin substitutes by seeding scaffolds with vessel-forming cells. These conventional approaches may be further supplemented by emerging strategies, such as transplantation of adipose tissue-derived microvascular fragments, 3D bioprinting and microfluidics, miRNA modulation, cell sheet engineering, and fabrication of photosynthetic scaffolds. The successful translation of these vascularization strategies from bench to bedside may pave the way for a broad clinical implementation of skin tissue engineering.
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Affiliation(s)
- Florian S Frueh
- a Institute for Clinical and Experimental Surgery , Saarland University , Homburg (Saar) , Germany.,b Division of Plastic Surgery and Hand Surgery , University Hospital Zurich , Zurich , Switzerland
| | - Michael D Menger
- a Institute for Clinical and Experimental Surgery , Saarland University , Homburg (Saar) , Germany
| | - Nicole Lindenblatt
- b Division of Plastic Surgery and Hand Surgery , University Hospital Zurich , Zurich , Switzerland
| | - Pietro Giovanoli
- b Division of Plastic Surgery and Hand Surgery , University Hospital Zurich , Zurich , Switzerland
| | - Matthias W Laschke
- a Institute for Clinical and Experimental Surgery , Saarland University , Homburg (Saar) , Germany
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546
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Xia B, Krutkramelis K, Oakey J. Oxygen-Purged Microfluidic Device to Enhance Cell Viability in Photopolymerized PEG Hydrogel Microparticles. Biomacromolecules 2016; 17:2459-65. [PMID: 27285343 PMCID: PMC7442217 DOI: 10.1021/acs.biomac.6b00597] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Encapsulating cells within biocompatible materials is a widely used strategy for cell delivery and tissue engineering. While cells are commonly suspended within bulk hydrogel-forming solutions during gelation, substantial interest in the microfluidic fabrication of miniaturized cell encapsulation vehicles has more recently emerged. Here, we utilize multiphase microfluidics to encapsulate cells within photopolymerized picoliter-volume water-in-oil droplets at high production rates. The photoinitiated polymerization of polyethylene glycol diacrylate (PEGDA) is used to continuously produce solid particles from aqueous liquid drops containing cells and hydrogel forming solution. It is well understood that this photoinitiated addition reaction is inhibited by oxygen. In contrast to bulk polymerization in which ambient oxygen is rapidly and harmlessly consumed, allowing the polymerization reaction to proceed, photopolymerization within air permeable polydimethylsiloxane (PDMS) microfluidic devices allows oxygen to be replenished by diffusion as it is depleted. This sustained presence of oxygen and the consequential accumulation of peroxy radicals produce a dramatic effect upon both droplet polymerization and post-encapsulation cell viability. In this work we employ a nitrogen microjacketed microfluidic device to purge oxygen from flowing fluids during photopolymerization. By increasing the purging nitrogen pressure, oxygen concentration was attenuated, and increased post-encapsulation cell viability was achieved. A reaction-diffusion model was used to predict the cumulative intradroplet concentration of peroxy radicals, which corresponded directly to post-encapsulation cell viability. The nitrogen-jacketed microfluidic device presented here allows the droplet oxygen concentration to be finely tuned during cell encapsulation, leading to high post-encapsulation cell viability.
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Affiliation(s)
- Bingzhao Xia
- Department of Chemical Engineering, University of Wyoming, Laramie, Wyoming 82071, United States
| | - Kaspars Krutkramelis
- Department of Chemical Engineering, University of Wyoming, Laramie, Wyoming 82071, United States
| | - John Oakey
- Department of Chemical Engineering, University of Wyoming, Laramie, Wyoming 82071, United States
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547
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Kahkeshani S, Di Carlo D. Drop formation using ferrofluids driven magnetically in a step emulsification device. LAB ON A CHIP 2016; 16:2474-80. [PMID: 27250530 DOI: 10.1039/c6lc00645k] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
We present a microfluidic droplet generation technique, where instead of pumps, only magnetic field gradient strength adjusted by the position of an external magnet is used for controllable emulsification of ferrofluid containing solutions. Uniform droplet generation at frequencies O(1-100) Hz per channel for long periods of time (10s of minutes) were easily achieved. In this method, adding magnetic nanoparticles (10 nm) into aqueous solutions imparts a magnetic body force on the fluid in the presence of an external magnetic field gradient. Consequently, the aqueous fluid moves toward the position of an external magnet and towards a junction with a larger width and height oil filled reservoir. Emulsification occurs at the junction due to a rapid change in surface tension forces due to the abrupt change in channel height. Droplet generation rate could be controlled by adjusting surface tension/viscosity, number of channels, and strength of the magnetic force. The geometry of the channel, rather than flow rates or magnetic force, plays the dominant role in defining the droplet size. In addition, reagents mixed with ferrofluids could also be introduced from two or more separate inlets and mixed prior to emulsification as they move toward the step driven by magnetic force. Mixing reagents on chip and forming droplets all within a small foot-print defined by movement of an external magnet is a unique feature of this method suitable for point-of-care diagnostics and other bioengineering applications.
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Affiliation(s)
- Soroush Kahkeshani
- Department of Bioengineering, University of California, Los Angeles, CA 90024, USA.
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548
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Tsou YH, Khoneisser J, Huang PC, Xu X. Hydrogel as a bioactive material to regulate stem cell fate. Bioact Mater 2016; 1:39-55. [PMID: 29744394 PMCID: PMC5883979 DOI: 10.1016/j.bioactmat.2016.05.001] [Citation(s) in RCA: 178] [Impact Index Per Article: 22.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2016] [Revised: 04/27/2016] [Accepted: 05/02/2016] [Indexed: 02/08/2023] Open
Abstract
The encapsulation of stem cells in a hydrogel substrate provides a promising future in biomedical applications. However, communications between hydrogels and stem cells is complicated; various factors such as porosity, different polymer types, stiffness, compatibility and degradation will lead to stem cell survival or death. Hydrogels mimic the three-dimensional extracellular matrix to provide a friendly environment for stem cells. On the other hand, stem cells can sense the surroundings to make the next progression, stretching out, proliferating or just to remain. As such, understanding the correlation between stem cells and hydrogels is crucial. In this Review, we first discuss the varying types of the hydrogels and stem cells, which are most commonly used in the biomedical fields and further investigate how hydrogels interact with stem cells from the perspective of their biomedical application, while providing insights into the design and development of hydrogels for drug delivery, tissue engineering and regenerative medicine purpose. In addition, we compare the results such as stiffness, degradation time and pore size as well as peptide types of hydrogels from respected journals. We also discussed most recently magnificent materials and their effects to regulate stem cell fate. Hydrogels as Extracellular Matrix (ECM) mimics stem cells proliferation and differentiation. Discuss how hydrogels interact with stem cells from the perspective of their biomedical applications. Recent magnificent materials and their effects to regulate stem cells fate.
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Affiliation(s)
- Yung-Hao Tsou
- Department of Chemical, Biological, and Pharmaceutical Engineering, New Jersey Institute of Technology, Newark, NJ 07102, USA
| | - Joe Khoneisser
- Department of Chemical, Biological, and Pharmaceutical Engineering, New Jersey Institute of Technology, Newark, NJ 07102, USA
| | - Ping-Chun Huang
- Department of Chemical, Biological, and Pharmaceutical Engineering, New Jersey Institute of Technology, Newark, NJ 07102, USA
| | - Xiaoyang Xu
- Department of Chemical, Biological, and Pharmaceutical Engineering, New Jersey Institute of Technology, Newark, NJ 07102, USA
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549
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Methods for Generating Hydrogel Particles for Protein Delivery. Ann Biomed Eng 2016; 44:1946-58. [PMID: 27160672 DOI: 10.1007/s10439-016-1637-z] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2016] [Accepted: 05/03/2016] [Indexed: 10/21/2022]
Abstract
Proteins represent a major class of therapeutic molecules with vast potential for the treatment of acute and chronic diseases and regenerative medicine applications. Hydrogels have long been investigated for their potential in carrying and delivering proteins. As compared to bulk hydrogels, hydrogel microparticles (microgels) hold promise in improving aspects of delivery owing to their less traumatic route of entry into the body and improved versatility. This review discusses common methods of fabricating microgels, including emulsion polymerization, microfluidic techniques, and lithographic techniques. Microgels synthesized from both natural and synthetic polymers are discussed, as are a series of microgels fashioned from environment-responsive materials.
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550
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Hydrogels for brain repair after stroke: an emerging treatment option. Curr Opin Biotechnol 2016; 40:155-163. [PMID: 27162093 DOI: 10.1016/j.copbio.2016.04.021] [Citation(s) in RCA: 75] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2015] [Revised: 04/02/2016] [Accepted: 04/20/2016] [Indexed: 12/23/2022]
Abstract
Stroke disability is the only major disease without an effective treatment. The substantial clinical burden of stroke in disabled survivors and the lack of a medical therapy that promotes recovery provide an opportunity to explore the use of biomaterials to promote brain repair after stroke. Hydrogels can be injected as a liquid and solidify in situ to form a gelatinous solid with similar mechanical properties to the brain. These biomaterials have been recently explored to generate pro-repair environments within the damaged organ. This review highlights the clinical problem of stroke treatment and discusses recent advances in using in situ forming hydrogels for brain repair.
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