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Memic A, Colombani T, Eggermont LJ, Rezaeeyazdi M, Steingold J, Rogers ZJ, Navare KJ, Mohammed HS, Bencherif SA. Latest Advances in Cryogel Technology for Biomedical Applications. ADVANCED THERAPEUTICS 2019. [DOI: 10.1002/adtp.201800114] [Citation(s) in RCA: 121] [Impact Index Per Article: 24.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Affiliation(s)
- Adnan Memic
- Center of NanotechnologyKing Abdulaziz University Jeddah 21589 Saudi Arabia
- Center for Biomedical EngineeringDepartment of MedicineBrigham and Women's HospitalHarvard Medical School Cambridge MA 02139 USA
- Department of Chemical EngineeringNortheastern University Boston MA 02115 USA
| | - Thibault Colombani
- Department of Chemical EngineeringNortheastern University Boston MA 02115 USA
| | - Loek J. Eggermont
- Department of Chemical EngineeringNortheastern University Boston MA 02115 USA
- Department of Tumor ImmunologyOncode Institute, Radboud Institute for Molecular Life SciencesRadboud University Medical Center Nijmegen 6500 The Netherlands
| | | | - Joseph Steingold
- Department of Pharmaceutical SciencesNortheastern University Boston MA 02115 USA
| | - Zach J. Rogers
- Department of Chemical EngineeringNortheastern University Boston MA 02115 USA
| | | | | | - Sidi A. Bencherif
- Department of Chemical EngineeringNortheastern University Boston MA 02115 USA
- Department of BioengineeringNortheastern University Boston MA 02115 USA
- Harvard John A. Paulson School of Engineering and Applied SciencesHarvard University Cambridge MA 02138 USA
- Sorbonne UniversityUTC CNRS UMR 7338Biomechanics and Bioengineering (BMBI)University of Technology of Compiègne Compiègne 60159 France
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De France KJ, Xu F, Hoare T. Structured Macroporous Hydrogels: Progress, Challenges, and Opportunities. Adv Healthc Mater 2018; 7. [PMID: 29195022 DOI: 10.1002/adhm.201700927] [Citation(s) in RCA: 104] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2017] [Revised: 09/15/2017] [Indexed: 12/15/2022]
Abstract
Structured macroporous hydrogels that have controllable porosities on both the nanoscale and the microscale offer both the swelling and interfacial properties of bulk hydrogels as well as the transport properties of "hard" macroporous materials. While a variety of techniques such as solvent casting, freeze drying, gas foaming, and phase separation have been developed to fabricate structured macroporous hydrogels, the typically weak mechanics and isotropic pore structures achieved as well as the required use of solvent/additives in the preparation process all limit the potential applications of these materials, particularly in biomedical contexts. This review highlights recent developments in the field of structured macroporous hydrogels aiming to increase network strength, create anisotropy and directionality within the networks, and utilize solvent-free or additive-free fabrication methods. Such functional materials are well suited for not only biomedical applications like tissue engineering and drug delivery but also selective filtration, environmental sorption, and the physical templating of secondary networks.
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Affiliation(s)
- Kevin J. De France
- Department of Chemical Engineering; McMaster University; 1280 Main Street West Hamilton ON L8S 4L8 Canada
| | - Fei Xu
- Department of Chemical Engineering; McMaster University; 1280 Main Street West Hamilton ON L8S 4L8 Canada
| | - Todd Hoare
- Department of Chemical Engineering; McMaster University; 1280 Main Street West Hamilton ON L8S 4L8 Canada
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3
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Combined “post-infiltration, subsequent photochemical cross-linking” and “cross-linking and selective etching” strategies to fabricate nanoporous layer-by-layer assembled multilayers. Colloid Polym Sci 2016. [DOI: 10.1007/s00396-016-3990-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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4
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Shim YB, Jung HH, Jang JW, Yang HS, Bae H, Park JC, Choi B, Lee SH. Fabrication of hollow porous PLGA microspheres using sucrose for controlled dual delivery of dexamethasone and BMP2. J IND ENG CHEM 2016. [DOI: 10.1016/j.jiec.2016.03.014] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
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5
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Mo R, Jiang T, Di J, Tai W, Gu Z. Emerging micro- and nanotechnology based synthetic approaches for insulin delivery. Chem Soc Rev 2014; 43:3595-629. [PMID: 24626293 DOI: 10.1039/c3cs60436e] [Citation(s) in RCA: 276] [Impact Index Per Article: 27.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Insulin is essential for type 1 and advanced type 2 diabetics to maintain blood glucose levels and prolong lives. The traditional administration requires frequent subcutaneous insulin injections that are associated with poor patient compliance, including pain, local tissue necrosis, infection, and nerve damage. Taking advantage of emerging micro- and nanotechnologies, numerous alternative strategies integrated with chemical approaches for insulin delivery have been investigated. This review outlines recent developments in the controlled delivery of insulin, including oral, nasal, pulmonary, transdermal, subcutaneous and closed-loop insulin delivery. Perspectives from new materials, formulations and devices at the micro- or nano-scales are specifically surveyed. Advantages and limitations of current delivery methods, as well as future opportunities and challenges are also discussed.
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Affiliation(s)
- Ran Mo
- Joint Department of Biomedical Engineering, University of North Carolina at Chapel Hill and North Carolina State University, Raleigh, NC 27695, USA.
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6
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Prieto EM, Page JM, Harmata AJ, Guelcher SA. Injectable foams for regenerative medicine. WILEY INTERDISCIPLINARY REVIEWS. NANOMEDICINE AND NANOBIOTECHNOLOGY 2014; 6:136-54. [PMID: 24127230 PMCID: PMC3945605 DOI: 10.1002/wnan.1248] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/17/2013] [Revised: 08/13/2013] [Accepted: 09/17/2013] [Indexed: 12/21/2022]
Abstract
The design of injectable biomaterials has attracted considerable attention in recent years. Many injectable biomaterials, such as hydrogels and calcium phosphate cements (CPCs), have nanoscale pores that limit the rate of cellular migration and proliferation. While introduction of macroporosity has been suggested to increase cellular infiltration and tissue healing, many conventional methods for generating macropores often require harsh processing conditions that preclude their use in injectable foams. In recent years, processes such as porogen leaching, gas foaming, and emulsion-templating have been adapted to generate macroporosity in injectable CPCs, hydrogels, and hydrophobic polymers. While some of the more mature injectable foam technologies have been evaluated in clinical trials, there are challenges remaining to be addressed, such as the biocompatibility and ultimate fate of the sacrificial phase used to generate pores within the foam after it sets in situ. Furthermore, while implantable scaffolds can be washed extensively to remove undesirable impurities, all of the components required to synthesize injectable foams must be injected into the defect. Thus, every compound in the foam must be biocompatible and noncytotoxic at the concentrations utilized. As future research addresses these critical challenges, injectable macroporous foams are anticipated to have an increasingly significant impact on improving patient outcomes for a number of clinical procedures.
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Affiliation(s)
- Edna M Prieto
- Department of Chemical and Biomolecular Engineering, Vanderbilt University, Nashville, TN, USA
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7
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Hawkins AM, Milbrandt TA, Puleo DA, Hilt JZ. Composite hydrogel scaffolds with controlled pore opening via biodegradable hydrogel porogen degradation. J Biomed Mater Res A 2013; 102:400-12. [PMID: 23686850 DOI: 10.1002/jbm.a.34697] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2012] [Revised: 02/20/2013] [Accepted: 02/21/2013] [Indexed: 02/01/2023]
Abstract
Poly(β-amino ester) (PBAE) biodegradable hydrogel systems have garnered much attention in recent years due to their appealing properties for biomedical applications. These hydrogel systems exhibit properties similar to natural soft tissue, degrade in aqueous environments, and have easily tunable properties that have been well studied and understood. In most cases, tissue engineering scaffolds must possess a three-dimensional interconnected porous network for tissue ingrowth and construct vascularization. Here, PBAE properties were explored and systems were selected to serve as both the pore-forming agent and the outer matrix of a scaffold that exhibits controlled pore opening upon degradation. To our knowledge, this is the first demonstration of a biodegradable hydrogel porogen system entrapped in a degradable hydrogel outer matrix. Scaffolds were prepared, and the degradation, compressive moduli, and porosity were analyzed. An added advantage of a degradable porogen is the potential for controlled drug release, and a model protein was released from the porogen particles to demonstrate this application. Finally, pluripotent cells seeded onto predegraded scaffolds were viable during the first 24 h of exposure, and furthermore, cell tracking confirmed the presence of cells within the pores of the scaffold. Overall, these present studies demonstrate the possibility of using these biodegradable hydrogel porogen-matrix systems as tissue engineering scaffolding materials.
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Affiliation(s)
- Ashley M Hawkins
- Department of Chemical and Materials Engineering, University of Kentucky, Lexington, Kentucky, 40506
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Mehraban M, Zadhoush A, Abdolkarim Hosseini Ravandi S, Bagheri R, Heidarkhan Tehrani A. Preparation of porous nanofibers from electrospun polyacrylonitrile/calcium carbonate composite nanofibers using porogen leaching technique. J Appl Polym Sci 2012. [DOI: 10.1002/app.38091] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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9
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Reis AF, Carrilho MRO, Ghaname E, Pereira PNR, Giannini M, Nikaido T, Tagami J. Effects of water-storage on the physical and ultramorphological features of adhesives and primer/adhesive mixtures. Dent Mater J 2010; 29:697-705. [PMID: 21099154 DOI: 10.4012/dmj.2009-091] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The aims of this study were to evaluate the ultimate tensile strength (UTS) and elastic modulus (E) of adhesives, and primer/adhesive mixtures after aging for 6 months in water or oil; and to compare silver uptake patterns under the TEM. A one-step self-etching adhesive (One-up Bond F: OB), two two-step self-etching primers (SE Bond: SE and Protect Bond: CP), and two etch-and-rinse systems (Single Bond: SB and Prime&Bond NT: PB) were used. Bonding and primer solutions of self-etching systems were also mixed (SE+P and CP+P). Most adhesives presented decreased UTS after water-storage. Similar or increased UTS was observed after oil storage. Except for SB, E values did not change after water-storage, but they increased after storage in oil. OB, CP+P and SE+P presented more silver uptake. The effects of water-storage were material-dependent, and significantly affected the mechanical properties and silver uptake patterns of adhesives.
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Affiliation(s)
- Andre F Reis
- Department of Operative Dentistry, Guarulhos University, SP, Brazil
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10
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Lee J, Oh YJ, Lee SK, Lee KY. Facile control of porous structures of polymer microspheres using an osmotic agent for pulmonary delivery. J Control Release 2010; 146:61-7. [DOI: 10.1016/j.jconrel.2010.05.026] [Citation(s) in RCA: 86] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2010] [Revised: 04/28/2010] [Accepted: 05/20/2010] [Indexed: 10/19/2022]
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11
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Martins AM, Alves CM, Kurtis Kasper F, Mikos AG, Reis RL. Responsive and in situ-forming chitosan scaffolds for bone tissue engineering applications: an overview of the last decade. ACTA ACUST UNITED AC 2010. [DOI: 10.1039/b916259n] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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12
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Rich J, Korhonen H, Hakala R, Korventausta J, Elomaa L, Seppälä J. Porous Biodegradable Scaffold: Predetermined Porosity by Dissolution of Poly(ester-anhydride) Fibers from Polyester Matrix. Macromol Biosci 2009; 9:654-60. [DOI: 10.1002/mabi.200800306] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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13
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Namba R, Cole A, Bjugstad K, Mahoney M. Development of porous PEG hydrogels that enable efficient, uniform cell-seeding and permit early neural process extension. Acta Biomater 2009; 5:1884-97. [PMID: 19250891 DOI: 10.1016/j.actbio.2009.01.036] [Citation(s) in RCA: 67] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2008] [Revised: 01/14/2009] [Accepted: 01/16/2009] [Indexed: 01/04/2023]
Abstract
Three-dimensional polymer scaffolds are useful culture systems for neural cell growth and can provide permissive substrates that support neural processes as they extend across lesions in the brain and spinal cord. Degradable poly(ethylene) glycol (PEG) gels have been identified as a particularly promising scaffold material for this purpose; however, process extension within PEG gels is limited to late stages of hydrogel degradation. Here we demonstrate that earlier process extension can be achieved from primary neural cells encapsulated within PEG gels by creating a network of interconnected pores throughout the gel. Our method of incorporating these pores involves co-encapsulating a cell solution and a fibrin network within a PEG gel. The fibrin is subsequently enzymatically degraded under cytocompatible conditions, leaving behind a network of interconnected pores within the PEG gel. The primary neural cell population encapsulated in the gel is of mixed composition, containing differentiated neurons, and multipotent neuronal and glial precursor cells. We demonstrate that the initial presence of fibrin does not influence the cell-fate decisions of the encapsulated precursor cells. We also demonstrate that this fabrication approach enables simple, efficient and uniform seeding of viable cells throughout the entire porous scaffold.
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Blaker JJ, Knowles JC, Day RM. Novel fabrication techniques to produce microspheres by thermally induced phase separation for tissue engineering and drug delivery. Acta Biomater 2008; 4:264-72. [PMID: 18032120 DOI: 10.1016/j.actbio.2007.09.011] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2007] [Revised: 09/17/2007] [Accepted: 09/25/2007] [Indexed: 11/18/2022]
Abstract
A novel application of thermally induced phase separation (TIPS) is described enabling the rapid formation of monodisperse porous microspheres. By taking advantage of TIPS processing parameters, the porosity, the pore morphology (bimodal/channel-like/radial towards the centre) and the presence of an open-pore or dense skin region can be tailored. Achievable sizes range from 10 to 2000microm in diameter. The technique facilitates the homogeneous inclusion of particulate fillers and drugs. Moreover, the combined TIPS/oil-in-water emulsion technique allows for the production of microspheres with isotropic pore morphology with interconnected spherical pores of 30-70microm and well-formed porous microspheres of 10-200microm in diameter with an open porous surface. This method is advantageous over existing techniques by avoiding the use of long-term exposure to an aqueous continuous phase as used in oil-in-water or water-in-oil-in-water processing and therefore drug encapsulation efficiencies will be higher.
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Affiliation(s)
- Jonny J Blaker
- Biomaterials and Tissue Engineering Group, Burdette Institute of Gastrointestinal Nursing, Kings College London, UK
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Ashton RS, Banerjee A, Punyani S, Schaffer DV, Kane RS. Scaffolds based on degradable alginate hydrogels and poly(lactide-co-glycolide) microspheres for stem cell culture. Biomaterials 2007; 28:5518-25. [PMID: 17881048 DOI: 10.1016/j.biomaterials.2007.08.038] [Citation(s) in RCA: 135] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2007] [Accepted: 08/27/2007] [Indexed: 11/19/2022]
Abstract
We describe a method for creating alginate hydrogels with adjustable degradation rates that can be used as scaffolds for stem cells. Alginate hydrogels have been widely tested as three-dimensional constructs for cell culture, cell carriers for implantation, and in tissue regeneration applications; however, alginate hydrogel implants can take months to disappear from implantation sites because mammals do not produce endogenous alginases. By incorporating poly(lactide-co-glycolide) (PLGA) microspheres loaded with alginate lyase into alginate hydrogels, we demonstrate that alginate hydrogels can be enzymatically degraded in a controlled and tunable fashion. We demonstrate that neural progenitor cells (NPCs) can be cultured and expanded in vitro in this degradable alginate hydrogel system. Moreover, we observe a significant increase in the expansion rate of NPCs cultured in degrading alginate hydrogels versus NPCs cultured in standard, i.e. non-degrading, alginate hydrogels. Degradable alginate hydrogels encapsulating stem cells may be widely applied to develop novel therapies for tissue regeneration.
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Affiliation(s)
- Randolph S Ashton
- The Howard P. Isermann Department of Chemical and Biological Engineering, Rensselaer Polytechnic Institute, Troy, NY 12180, USA
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16
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Reis AF, Giannini M, Pereira PNR. Influence of water-storage time on the sorption and solubility behavior of current adhesives and primer/adhesive mixtures. Oper Dent 2007; 32:53-9. [PMID: 17288329 DOI: 10.2341/06-13] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
This study evaluated the effects of water-storage on the water sorption and solubility behavior of five commercially available dental adhesive systems and two primer/adhesive mixtures. The adhesives comprised three different approaches to bonding to hard tooth tissues: a one-step self-etching adhesive (One-up Bond F), two two-step self-etching primers (Clearfil SE Bond and Clearfil Protect Bond) and two etch-and-rinse systems: a water/ethanol-based (Single Bond) and an acetone-based filled adhesive (Prime&Bond NT). The bonding agents and primers of the two-step self-etching systems were mixed in a 1:1 volume ratio. Water sorption and solubility values were determined after 1, 7, 30, 90 and 180 days. The results showed that, except for SB, all adhesives presented increased water sorption with increased storage time. The one-step self-etching adhesive and self-etching primer/adhesive mixtures presented the highest water sorption and solubility values. Equilibrium in the water sorption values was observed for all adhesives after 90 days of water-storage. However, solubility values continued to increase for some materials until 180 days. The sorption and solubility behavior of the materials tested seem to be related to hydrophilicity of the adhesive resin solution and might influence the long-term performance of resin-based composite restorations.
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Affiliation(s)
- Andre F Reis
- Department of Restorative Dentistry, Division of Operative Dentistry, Piracicaba School of Dentistry, University of Campinas, Brazil
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Kretlow JD, Klouda L, Mikos AG. Injectable matrices and scaffolds for drug delivery in tissue engineering. Adv Drug Deliv Rev 2007; 59:263-73. [PMID: 17507111 DOI: 10.1016/j.addr.2007.03.013] [Citation(s) in RCA: 429] [Impact Index Per Article: 25.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2007] [Accepted: 03/28/2007] [Indexed: 11/22/2022]
Abstract
Injectable matrices and depots have been the subject of much research in the field of drug delivery. The classical tissue engineering paradigm includes a matrix or scaffold to facilitate tissue growth and provide structural support, cells, and the delivery of bioactive molecules. As both tissue engineering and drug delivery techniques benefit from the use of injectable materials due to the minimal invasiveness of an injection, significant crossover should be observed between injectable materials in both fields. This review aims to outline injectable materials and processing techniques used in both tissue engineering and drug delivery and to describe methods by which current injectable materials in the field of drug delivery can be adapted for use as injectable scaffolds for tissue engineering.
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Affiliation(s)
- James D Kretlow
- Department of Bioengineering, Rice University, Houston, TX 77251-1892, USA
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18
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A preliminary study on fabrication of nanoscale fibrous chitosan membranes in situ by biospecific degradation. J Memb Sci 2006. [DOI: 10.1016/j.memsci.2006.01.011] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Zhai L, Nolte AJ, Cohen RE, Rubner MF. pH-Gated Porosity Transitions of Polyelectrolyte Multilayers in Confined Geometries and Their Application as Tunable Bragg Reflectors. Macromolecules 2004. [DOI: 10.1021/ma049593e] [Citation(s) in RCA: 128] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Lei Zhai
- Department of Chemical Engineering and of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139
| | - Adam J. Nolte
- Department of Chemical Engineering and of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139
| | - Robert E. Cohen
- Department of Chemical Engineering and of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139
| | - Michael F. Rubner
- Department of Chemical Engineering and of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139
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Leddy HA, Awad HA, Guilak F. Molecular diffusion in tissue-engineered cartilage constructs: Effects of scaffold material, time, and culture conditions. ACTA ACUST UNITED AC 2004; 70:397-406. [PMID: 15264325 DOI: 10.1002/jbm.b.30053] [Citation(s) in RCA: 112] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Diffusion is likely to be the primary mechanism for macromolecular transport in tissue-engineered cartilage, and providing an adequate nutrient supply via diffusion may be necessary for cell proliferation and extracellular matrix production. The goal of this study was to measure the diffusivity of tissue-engineered cartilage constructs as a function of scaffold material, culture conditions, and time in culture. Diffusion coefficients of four different-sized fluorescent dextrans were measured by fluorescence recovery after photobleaching in tissue-engineered cartilage constructs seeded with human adipose-derived stem cells or acellular constructs on scaffolds of alginate, agarose, gelatin, or fibrin that were cultured for 1 or 28 days in either chondrogenic or control conditions. Diffusivities in the constructs were much greater than those of native cartilage. The diffusivity of acellular constructs increased 62% from Day 1 to Day 28, whereas diffusivity of cellular constructs decreased 42% and 27% in chondrogenic and control cultures, respectively. The decrease in diffusivity in cellular constructs is likely due to new matrix synthesis, which may be enhanced with chondrogenic media, and matrix contraction by the cells in the fibrin and gelatin scaffolds. The increase in diffusivity in the acellular constructs is probably due to scaffold degradation and swelling.
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Affiliation(s)
- Holly A Leddy
- Department of Surgery, Duke University Medical Center, Durham, North Carolina 27710, USA
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