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Beheshtizadeh N, Gharibshahian M, Bayati M, Maleki R, Strachan H, Doughty S, Tayebi L. Vascular endothelial growth factor (VEGF) delivery approaches in regenerative medicine. Biomed Pharmacother 2023; 166:115301. [PMID: 37562236 DOI: 10.1016/j.biopha.2023.115301] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2023] [Revised: 07/28/2023] [Accepted: 08/05/2023] [Indexed: 08/12/2023] Open
Abstract
The utilization of growth factors in the process of tissue regeneration has garnered significant interest and has been the subject of extensive research. However, despite the fervent efforts invested in recent clinical trials, a considerable number of these studies have produced outcomes that are deemed unsatisfactory. It is noteworthy that the trials that have yielded the most satisfactory outcomes have exhibited a shared characteristic, namely, the existence of a mechanism for the regulated administration of growth factors. Despite the extensive exploration of drug delivery vehicles and their efficacy in delivering certain growth factors, the development of a reliable predictive approach for the delivery of delicate growth factors like Vascular Endothelial Growth Factor (VEGF) remains elusive. VEGF plays a crucial role in promoting angiogenesis; however, the administration of VEGF demands a meticulous approach as it necessitates precise localization and transportation to a specific target tissue. This process requires prolonged and sustained exposure to a low concentration of VEGF. Inaccurate administration of drugs, either through off-target effects or inadequate delivery, may heighten the risk of adverse reactions and potentially result in tumorigenesis. At present, there is a scarcity of technologies available for the accurate encapsulation of VEGF and its subsequent sustained and controlled release. The objective of this review is to present and assess diverse categories of VEGF administration mechanisms. This paper examines various systems, including polymeric, liposomal, hydrogel, inorganic, polyplexes, and microfluidic, and evaluates the appropriate dosage of VEGF for multiple applications.
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Affiliation(s)
- Nima Beheshtizadeh
- Department of Tissue Engineering, School of Advanced Technologies in Medicine, Tehran University of Medical Sciences, Iran; Regenerative Medicine group (REMED), Universal Scientific Education and Research Network (USERN), Tehran, Iran.
| | - Maliheh Gharibshahian
- Department of Tissue Engineering, School of Medicine, Shahroud University of Medical Sciences, Shahroud, Iran; Regenerative Medicine group (REMED), Universal Scientific Education and Research Network (USERN), Tehran, Iran
| | - Mohammad Bayati
- Department of Phytochemistry, Medicinal Plants and Drugs Research Institute, Shahid Beheshti University, Tehran, Iran
| | - Reza Maleki
- Department of Chemical Technologies, Iranian Research Organization for Science and Technology (IROST), P.O. Box 33535111, Tehran, Iran.
| | - Hannah Strachan
- Marquette University School of Dentistry, Milwaukee, WI 53233, USA
| | - Sarah Doughty
- Marquette University School of Dentistry, Milwaukee, WI 53233, USA
| | - Lobat Tayebi
- Marquette University School of Dentistry, Milwaukee, WI 53233, USA
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2
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Abune L, Lee K, Wang Y. Development of a Biomimetic Extracellular Matrix with Functions of Protein Sequestration and Cell Attachment Using Dual Aptamer-Functionalized Hydrogels. ACS Biomater Sci Eng 2022; 8:1279-1289. [PMID: 35179358 PMCID: PMC9764160 DOI: 10.1021/acsbiomaterials.1c01544] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The extracellular matrix (ECM) has not only cell-binding sites for cell attachment but also protein-binding sites for molecular sequestration. Aptamers have high binding affinities and specificities against their target molecules. Thus, the purpose of this work was to develop dual aptamer-functionalized hydrogels for simultaneously recapitulating the two key features of the ECM in binding cells and sequestering proteins. We synthesized the hydrogels using free-radical polymerization in a freezing procedure. As the hydrogels were macroporous with pores of 40-50 μm, both cells and proteins could be loaded into the hydrogels after the synthesis. Importantly, the vascular endothelial growth factor (VEGF) aptamer improved VEGF sequestration and reduced the apparent diffusivity of VEGF by over 2 orders of magnitude, resultantly prolonging VEGF retention and release. The c-MET aptamer promoted the attachment of endothelial cells in the hydrogel network. When two aptamers were both incorporated into the hydrogel, they could produce synergistic effects on cell survival and growth. Thus, this work has successfully demonstrated the potential of developing biomimetic ECMs with two key functions of cell attachment and protein sequestration using dual aptamer-functionalized hydrogels.
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Affiliation(s)
- Lidya Abune
- Department of Biomedical Engineering, The Pennsylvania State University, 122 CBE Building, University Park, Pennsylvania 16801, United States
| | - Kyungsene Lee
- Department of Biomedical Engineering, The Pennsylvania State University, 122 CBE Building, University Park, Pennsylvania 16801, United States
| | - Yong Wang
- Department of Biomedical Engineering, The Pennsylvania State University, 122 CBE Building, University Park, Pennsylvania 16801, United States
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3
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Prabhath A, Vernekar VN, Vasu V, Badon M, Avochinou JE, Asandei AD, Kumbar SG, Weber E, Laurencin CT. Kinetic degradation and biocompatibility evaluation of polycaprolactone-based biologics delivery matrices for regenerative engineering of the rotator cuff. J Biomed Mater Res A 2021; 109:2137-2153. [PMID: 33974735 PMCID: PMC8440380 DOI: 10.1002/jbm.a.37200] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2021] [Revised: 03/26/2021] [Accepted: 04/07/2021] [Indexed: 11/06/2022]
Abstract
Whereas synthetic biodegradable polymers have been successfully applied for the delivery of biologics in other tissues, the anatomical complexity, poor blood supply, and reduced clearance of degradation byproducts in the rotator cuff create unique design challenges for implantable biomaterials. Here, we investigated lower molecular weight poly-lactic acid co-epsilon-caprolactone (PLA-CL) formulations with varying molecular weight and film casting concentrations as potential matrices for the therapeutic delivery of biologics in the rotator cuff. Matrices were fabricated with target footprint dimensions to facilitate controlled and protected release of model biologic (Bovine Serum Albumin), and anatomically-unhindered implantation under the acromion in a rodent model of acute rotator cuff repair. The matrix obtained from the highest polymeric-film casting concentration showed a controlled release of model biologics payload. The tested matrices rapidly degraded during the initial 4 weeks due to preferential hydrolysis of the lactide-rich regions within the polymer, and subsequently maintained a stable molecular weight due to the emergence of highly-crystalline caprolactone-rich regions. pH evaluation in the interior of the matrix showed minimal change signifying lesser accumulation of acidic degradation byproducts than seen in other bulk-degrading polymers, and maintenance of conformational stability of the model biologic payload. The context-dependent biocompatibility evaluation in a rodent model of acute rotator cuff repair showed matrix remodeling without eliciting excessive inflammatory reaction and is anticipated to completely degrade within 6 months. The engineered PLA-CL matrices offer unique advantages in controlled and protected biologic delivery, non-toxic biodegradation, and biocompatibility overcoming several limitations of commonly-used biodegradable polyesters.
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Affiliation(s)
- Anupama Prabhath
- Connecticut Convergence Institute for Translation in Regenerative Engineering, UConn Health, Farmington, Connecticut, USA
- Department of Orthopaedic Surgery, UConn Health, Farmington, Connecticut, USA
- Department of Biomedical Engineering, UConn Health, Farmington, Connecticut, USA
| | - Varadraj N Vernekar
- Connecticut Convergence Institute for Translation in Regenerative Engineering, UConn Health, Farmington, Connecticut, USA
- Department of Orthopaedic Surgery, UConn Health, Farmington, Connecticut, USA
| | - Vignesh Vasu
- Department of Material Science and Engineering, University of Connecticut, Storrs, Connecticut, USA
| | - Mary Badon
- Connecticut Convergence Institute for Translation in Regenerative Engineering, UConn Health, Farmington, Connecticut, USA
| | - Jean-Emmanuel Avochinou
- Connecticut Convergence Institute for Translation in Regenerative Engineering, UConn Health, Farmington, Connecticut, USA
| | - Alexandru D Asandei
- Department of Material Science and Engineering, University of Connecticut, Storrs, Connecticut, USA
| | - Sangamesh G Kumbar
- Department of Orthopaedic Surgery, UConn Health, Farmington, Connecticut, USA
- Department of Biomedical Engineering, UConn Health, Farmington, Connecticut, USA
- Department of Material Science and Engineering, University of Connecticut, Storrs, Connecticut, USA
| | - Eckhard Weber
- Musculoskeletal Division, Novartis Institutes for BioMedical Research (NIBR), Basel, Switzerland
| | - Cato T Laurencin
- Connecticut Convergence Institute for Translation in Regenerative Engineering, UConn Health, Farmington, Connecticut, USA
- Department of Orthopaedic Surgery, UConn Health, Farmington, Connecticut, USA
- Department of Biomedical Engineering, UConn Health, Farmington, Connecticut, USA
- Department of Material Science and Engineering, University of Connecticut, Storrs, Connecticut, USA
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4
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Abune L, Davis B, Wang Y. Aptamer-functionalized hydrogels: An emerging class of biomaterials for protein delivery, cell capture, regenerative medicine, and molecular biosensing. WILEY INTERDISCIPLINARY REVIEWS-NANOMEDICINE AND NANOBIOTECHNOLOGY 2021; 13:e1731. [PMID: 34132055 DOI: 10.1002/wnan.1731] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/12/2021] [Revised: 04/27/2021] [Accepted: 05/24/2021] [Indexed: 12/25/2022]
Abstract
Molecular recognition is essential to the development of biomaterials. Aptamers are a unique class of synthetic ligands interacting with not only their target molecules with high affinities and specificities but also their complementary sequences with high fidelity. Thus, aptamers have recently attracted significant attention in the development of an emerging class of biomaterials, that is, aptamer-functionalized hydrogels. In this review, we introduce the methods of incorporating aptamers into hydrogels as pendant motifs or crosslinkers. We further introduce the functions of these hydrogels in recognizing proteins, cells, and analytes through four applications including protein delivery, cell capture, regenerative medicine, and molecular biosensing. Notably, as aptamer-functionalized hydrogels have the characteristics of both aptamers and hydrogels, their potential applications are broad and beyond the scope of this review. This article is categorized under: Biology-Inspired Nanomaterials > Nucleic Acid-Based Structures Implantable Materials and Surgical Technologies > Nanomaterials and Implants Therapeutic Approaches and Drug Discovery > Emerging Technologies.
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Affiliation(s)
- Lidya Abune
- Department of Biomedical Engineering, The Pennsylvania State University, University Park, Pennsylvania, USA
| | - Brandon Davis
- Department of Biomedical Engineering, The Pennsylvania State University, University Park, Pennsylvania, USA
| | - Yong Wang
- Department of Biomedical Engineering, The Pennsylvania State University, University Park, Pennsylvania, USA
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5
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Rother S, Ruiz-Gómez G, Balamurugan K, Koehler L, Fiebig KM, Galiazzo VD, Hempel U, Moeller S, Schnabelrauch M, Waltenberger J, Pisabarro MT, Scharnweber D, Hintze V. Hyaluronan/Collagen Hydrogels with Sulfated Glycosaminoglycans Maintain VEGF165 Activity and Fine-Tune Endothelial Cell Response. ACS APPLIED BIO MATERIALS 2020; 4:494-506. [DOI: 10.1021/acsabm.0c01001] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Affiliation(s)
- Sandra Rother
- Institute of Materials Science, Max Bergmann Center of Biomaterials, TU Dresden, Budapester Str. 27, 01069 Dresden, Germany
| | - Gloria Ruiz-Gómez
- Structural Bioinformatics, BIOTEC TU Dresden, Tatzberg 47-51, Dresden 01307, Germany
| | | | - Linda Koehler
- Institute of Materials Science, Max Bergmann Center of Biomaterials, TU Dresden, Budapester Str. 27, 01069 Dresden, Germany
| | - Karen M. Fiebig
- Institute of Materials Science, Max Bergmann Center of Biomaterials, TU Dresden, Budapester Str. 27, 01069 Dresden, Germany
| | - Vanessa D. Galiazzo
- Institute of Materials Science, Max Bergmann Center of Biomaterials, TU Dresden, Budapester Str. 27, 01069 Dresden, Germany
| | - Ute Hempel
- Institute of Physiological Chemistry, Carl Gustav Carus Faculty of Medicine, TU Dresden, Fiedlerstraße 42, 01307 Dresden, Germany
| | - Stephanie Moeller
- Biomaterials Department, INNOVENT e.V., Prüssingstr. 27B, 07745 Jena, Germany
| | | | - Johannes Waltenberger
- Department of Cardiovascular Medicine, University of Münster, Albert-Schweitzer-Campus 1, 48149 Münster, Germany
| | - M. Teresa Pisabarro
- Structural Bioinformatics, BIOTEC TU Dresden, Tatzberg 47-51, Dresden 01307, Germany
| | - Dieter Scharnweber
- Institute of Materials Science, Max Bergmann Center of Biomaterials, TU Dresden, Budapester Str. 27, 01069 Dresden, Germany
| | - Vera Hintze
- Institute of Materials Science, Max Bergmann Center of Biomaterials, TU Dresden, Budapester Str. 27, 01069 Dresden, Germany
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6
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Mohajeri S, Burke-Kleinman J, Maurice DH, Amsden BG. Formulation parameters governing sustained protein delivery from degradable viscous liquid aliphatic polycarbonates. Int J Pharm 2020; 590:119965. [PMID: 33045320 DOI: 10.1016/j.ijpharm.2020.119965] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2020] [Revised: 09/28/2020] [Accepted: 10/06/2020] [Indexed: 11/18/2022]
Abstract
Viscous liquid degradable polymers have advantages as drug depots for sustained protein delivery. We have created a new aliphatic polycarbonate for this purpose, poly(trimethylene carbonate-co-5-hydroxy trimethylene carbonate), which upon degradation retains a near neutral micro-environmental pH. As such, this copolymer is highly suited to the delivery of acid sensitive proteins. We show that the mechanism of protein release from this liquid copolymer is consistent with the formation of super-hydrated regions as a result of the osmotic activity of the solution formed upon distributed protein particle dissolution. Protein release can be manipulated by controlling polymer hydrophobicity which can be adjusted by molecular weight and choice of initiator. Moreover, protein release is highly dependent on protein solubility which impacts the osmotic activity of the solution formed upon dissolution of the protein particles while protein molecular size and isoelectric point are not as influential. As demonstrated by the release of highly bioactive vascular endothelial growth factor, formulations of this copolymer are suitable for prolonged delivery of protein therapeutics.
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Affiliation(s)
- Sara Mohajeri
- Department of Chemical Engineering, Queen's University, Kingston, Ontario K7L 3N6, Canada; Human Mobility Research Centre, Kingston General Hospital, Kingston, Ontario K7L 2V7, Canada
| | - Jonah Burke-Kleinman
- Department of Biomedical and Molecular Sciences, Queen's University, Kingston K7L 3N6, Canada
| | - Donald H Maurice
- Department of Biomedical and Molecular Sciences, Queen's University, Kingston K7L 3N6, Canada
| | - Brian G Amsden
- Department of Chemical Engineering, Queen's University, Kingston, Ontario K7L 3N6, Canada; Human Mobility Research Centre, Kingston General Hospital, Kingston, Ontario K7L 2V7, Canada.
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7
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Bednarek M, Borska K, Kubisa P. Crosslinking of Polylactide by High Energy Irradiation and Photo-Curing. Molecules 2020; 25:E4919. [PMID: 33114261 PMCID: PMC7660633 DOI: 10.3390/molecules25214919] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2020] [Revised: 10/20/2020] [Accepted: 10/20/2020] [Indexed: 12/19/2022] Open
Abstract
Polylactide (PLA) is presently the most studied bioderived polymer because, in addition to its established position as a material for biomedical applications, it can replace mass production plastics from petroleum. However, some drawbacks of polylactide such as insufficient mechanical properties at a higher temperature and poor shape stability have to be overcome. One of the methods of mechanical and thermal properties modification is crosslinking which can be achieved by different approaches, both at the stage of PLA-based materials synthesis and by physical modification of neat polylactide. This review covers PLA crosslinking by applying different types of irradiation, i.e., high energy electron beam or gamma irradiation and UV light which enables curing at mild conditions. In the last section, selected examples of biomedical applications as well as applications for packaging and daily-use items are presented in order to visualize how a variety of materials can be obtained using specific methods.
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Affiliation(s)
- Melania Bednarek
- Centre of Molecular and Macromolecular Studies, Polish Academy of Sciences, Sienkiewicza 112, 90-362 Lodz, Poland; (K.B.); (P.K.)
| | - Katarina Borska
- Centre of Molecular and Macromolecular Studies, Polish Academy of Sciences, Sienkiewicza 112, 90-362 Lodz, Poland; (K.B.); (P.K.)
- Polymer Institute, Slovak Academy of Sciences, Dubravska Cesta 9, 845 41 Bratislava, Slovakia
| | - Przemysław Kubisa
- Centre of Molecular and Macromolecular Studies, Polish Academy of Sciences, Sienkiewicza 112, 90-362 Lodz, Poland; (K.B.); (P.K.)
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8
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Mohajeri S, Chen F, de Prinse M, Phung T, Burke-Kleinman J, Maurice DH, Amsden BG. Liquid Degradable Poly(trimethylene-carbonate-co-5-hydroxy-trimethylene carbonate): An Injectable Drug Delivery Vehicle for Acid-Sensitive Drugs. Mol Pharm 2020; 17:1363-1376. [DOI: 10.1021/acs.molpharmaceut.0c00064] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Affiliation(s)
- Sara Mohajeri
- Department of Chemical Engineering, Queen’s University, Kingston, Ontario K7L 3N6, Canada
- Human Mobility Research Centre, Kingston General Hospital, Kingston, Ontario K7L 2V7, Canada
| | - Fei Chen
- Department of Chemical Engineering, Queen’s University, Kingston, Ontario K7L 3N6, Canada
- Human Mobility Research Centre, Kingston General Hospital, Kingston, Ontario K7L 2V7, Canada
- Institute of Synthetic Biology, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China
| | - Mitchell de Prinse
- Department of Chemical Engineering, Queen’s University, Kingston, Ontario K7L 3N6, Canada
- Human Mobility Research Centre, Kingston General Hospital, Kingston, Ontario K7L 2V7, Canada
| | - Ta Phung
- Department of Chemical Engineering, Queen’s University, Kingston, Ontario K7L 3N6, Canada
- Human Mobility Research Centre, Kingston General Hospital, Kingston, Ontario K7L 2V7, Canada
| | - Jonah Burke-Kleinman
- Department of Biomedical and Molecular Sciences, Queen’s University, Kingston K7L 3N6, Canada
| | - Donald H. Maurice
- Department of Biomedical and Molecular Sciences, Queen’s University, Kingston K7L 3N6, Canada
| | - Brian G. Amsden
- Department of Chemical Engineering, Queen’s University, Kingston, Ontario K7L 3N6, Canada
- Human Mobility Research Centre, Kingston General Hospital, Kingston, Ontario K7L 2V7, Canada
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9
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Development of hydrogel-like biomaterials via nanoparticle assembly and solid-hydrogel transformation. J Control Release 2019; 318:185-196. [PMID: 31857102 DOI: 10.1016/j.jconrel.2019.12.026] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2019] [Revised: 12/07/2019] [Accepted: 12/15/2019] [Indexed: 11/22/2022]
Abstract
Hydrogels for biomedical applications such as controlled drug release are usually synthesized with the chemical or physical crosslinking of monomers or macromers. In this work, we used gelatin to prepare hydrogel nanoparticles and studied whether gelatin nanoparticles (GNPs) could assemble to form a solid biomaterial and whether this solid biomaterial was capable of transforming into a hydrogel upon introduction to a hydrated environment. The data show that GNPs with or without aptamer functionalization could form a nanoparticle-assembled porous solid biomaterial after freezing and lyophilization treatment. This formation did not need any additional crosslinking reactions. More importantly, this solid biomaterial could undergo solid-to-hydrogel transition after contacting a solution and this transformation was tunable to match different shapes and geometries of defined molds. The formed hydrogel could also sequester and release growth factors for the promotion of skin wound healing. Thus, GNP-assembled solid biomaterials hold great potential as an off-the-shelf therapy for biomedical application such as drug delivery and regenerative medicine.
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10
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Zhao N, Suzuki A, Zhang X, Shi P, Abune L, Coyne J, Jia H, Xiong N, Zhang G, Wang Y. Dual Aptamer-Functionalized in Situ Injectable Fibrin Hydrogel for Promotion of Angiogenesis via Codelivery of Vascular Endothelial Growth Factor and Platelet-Derived Growth Factor-BB. ACS APPLIED MATERIALS & INTERFACES 2019; 11:18123-18132. [PMID: 31026135 PMCID: PMC6542593 DOI: 10.1021/acsami.9b02462] [Citation(s) in RCA: 43] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
In situ injectable hydrogels hold great potential for in vivo applications such as drug delivery and regenerative medicine. However, it is challenging to ensure stable sequestration and sustained release of loaded biomolecules in these hydrogels. As aptamers have high binding affinities and specificities against target biomolecules, we studied the capability of aptamers in functionalizing in situ injectable fibrin (Fn) hydrogels for in vivo delivery of two growth factors including vascular endothelial growth factor (VEGF) and platelet-derived growth factor-BB (PDGF-BB). The results show that aptamer-functionalized fibrinogen (Fg) could form in situ injectable Fn hydrogels with porous structures. The aptamer-functionalized Fn hydrogels could sequester more VEGF and PDGF-BB than the native Fn and release these growth factors in a sustained manner with high bioactivity. After the aptamer-functionalized Fn hydrogels were subcutaneously injected into mice, the codelivery of VEGF and PDGF-BB could promote the growth of mature blood vessels. Therefore, this study has successfully demonstrated that aptamer-functionalized in situ injectable hydrogels hold great potential for in vivo codelivery of multiple growth factors and promotion of angiogenesis .
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Affiliation(s)
- Nan Zhao
- Department of Biomedical Engineering, The Pennsylvania State University, University Park, PA 16802, USA
| | - Akiho Suzuki
- Department of Biomedical Engineering, The Pennsylvania State University, University Park, PA 16802, USA
| | - Xiaolong Zhang
- Department of Biomedical Engineering, The Pennsylvania State University, University Park, PA 16802, USA
| | - Peng Shi
- Department of Biomedical Engineering, The Pennsylvania State University, University Park, PA 16802, USA
| | - Lidya Abune
- Department of Biomedical Engineering, The Pennsylvania State University, University Park, PA 16802, USA
| | - James Coyne
- Department of Biomedical Engineering, The Pennsylvania State University, University Park, PA 16802, USA
| | - Huizhen Jia
- Department of Biomedical Engineering, The Pennsylvania State University, University Park, PA 16802, USA
| | - Na Xiong
- Department of Veterinary and Biomedical Sciences, The Pennsylvania State University, University Park, PA 16802, USA
| | - Ge Zhang
- Department of Biomedical Engineering, The University of Akron, Akron, OH, 44325, USA
| | - Yong Wang
- Department of Biomedical Engineering, The Pennsylvania State University, University Park, PA 16802, USA
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11
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McBride JW, Boyd P, Dias N, Cameron D, Offord RE, Hartley O, Kett VL, Malcolm RK. Vaginal rings with exposed cores for sustained delivery of the HIV CCR5 inhibitor 5P12-RANTES. J Control Release 2019; 298:1-11. [PMID: 30731150 PMCID: PMC6414755 DOI: 10.1016/j.jconrel.2019.02.003] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2018] [Revised: 01/28/2019] [Accepted: 02/02/2019] [Indexed: 11/29/2022]
Abstract
Antiretroviral-releasing vaginal rings are at the forefront of ongoing efforts to develop microbicide-based strategies for prevention of heterosexual transmission of the human immunodeficiency virus (HIV). However, traditional ring designs are generally only useful for vaginal administration of relatively potent, lipophilic, and small molecular weight drug molecules that have sufficient permeability in the non-biodegradable silicone elastomer or thermoplastic polymers. Here, we report a novel, easy-to-manufacture 'exposed-core' vaginal ring that provides sustained release of the protein microbicide candidate 5P12-RANTES, an experimental chemokine analogue that potently blocks the HIV CCR5 coreceptor. In vitro release, mechanical, and stability testing demonstrated the utility and practicality of this novel ring design. In a sheep pharmacokinetic model, a ring containing two ¼-length excipient-modified silicone elastomer cores - each containing lyophilised 5P12-RANTES and exposed to the external environment by two large windows - provided sustained concentrations of 5P12-RANTES in vaginal fluid and vaginal tissue between 10 and 10,000 ng/g over 28days, at least 50 and up to 50,000 times the reported in vitro IC50 value.
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Affiliation(s)
- John W McBride
- School of Pharmacy, Queen's University Belfast, Belfast BT9 7BL, UK
| | - Peter Boyd
- School of Pharmacy, Queen's University Belfast, Belfast BT9 7BL, UK
| | | | | | - Robin E Offord
- Mintaka Foundation for Medical Research, Geneva, Switzerland
| | - Oliver Hartley
- Mintaka Foundation for Medical Research, Geneva, Switzerland; Department of Pathology and Immunology, Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - Vicky L Kett
- School of Pharmacy, Queen's University Belfast, Belfast BT9 7BL, UK
| | - R Karl Malcolm
- School of Pharmacy, Queen's University Belfast, Belfast BT9 7BL, UK.
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12
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van Bochove B, Grijpma DW. Photo-crosslinked synthetic biodegradable polymer networks for biomedical applications. JOURNAL OF BIOMATERIALS SCIENCE-POLYMER EDITION 2019; 30:77-106. [DOI: 10.1080/09205063.2018.1553105] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Affiliation(s)
- Bas van Bochove
- Department of Biomaterials Science and Technology, Faculty of Science and Technology, Technical Medical Centre University of Twente, Enschede, The Netherlands
| | - Dirk W. Grijpma
- Department of Biomaterials Science and Technology, Faculty of Science and Technology, Technical Medical Centre University of Twente, Enschede, The Netherlands
- Department of Biomedical Engineering, W. J. Kolff Institute, University Medical Centre, University of Groningen, Groningen, The Netherlands
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13
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Abstract
Programmable hydrogels are defined as hydrogels that are able to change their properties and functions periodically, reversibly and/or sequentially on demand. They are different from those responsive hydrogels whose changes are passive or cannot be stopped or reversed once started and vice versa. The purpose of this review is to summarize major progress in developing programmable hydrogels from the viewpoints of principles, functions and biomedical applications. The principles are first introduced in three categories including biological, chemical and physical stimulation. With the stimulation, programmable hydrogels can undergo functional changes in dimension, mechanical support, cell attachment and molecular sequestration, which are introduced in the middle of this review. The last section is focused on the introduction and discussion of four biomedical applications including mechanistic studies in mechanobiology, tissue engineering, cell separation and protein delivery.
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Affiliation(s)
- Yong Wang
- Department of Biomedical Engineering, The Pennsylvania State University University Park, PA 16802, USA.
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14
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McGann CL, Streifel BC, Lundin JG, Wynne JH. Multifunctional polyHIPE wound dressings for the treatment of severe limb trauma. POLYMER 2017. [DOI: 10.1016/j.polymer.2017.05.067] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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15
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Guo F, Zhang W, Pei X, Shen X, Yan Q, Li H, Yun J, Yang G. Biodegradable star-shaped polycyclic ester elastomers: Preparation, degradability, protein release, and biocompatibility in vitro. J BIOACT COMPAT POL 2016. [DOI: 10.1177/0883911516664194] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Effective local delivery methods for sustained and stable release of protein drugs are urgently needed. Biodegradable elastomers based on star-shaped polycyclic esters have received attention for their drug-loading and drug-release kinetics. However, the long degradation periods resulting from their strong lipophilicity greatly hinder their application. In this study, we synthesized new cross-linked elastomers based on methyl-acrylic-star-poly(ϵ-caprolactone- co-d,l-lactide) cyclic ester and methyl-bi-acrylic-poly(ϵ-caprolactone-b-poly(ethylene glycol)-b-ϵ-caprolactone) with different molecular weights; determined their physical, thermal, and morphological characteristics; and studied their in vitro degradation and release of bovine serum albumin and recombinant human interleukin 2. Elastomer hydrophilicity improved with the introduction of methyl-bi-acrylic-poly(ϵ-caprolactone-b-poly(ethylene glycol)-b-ϵ-caprolactone), and a shorter degradation period (~25 weeks) was achieved. Additionally, the degradation rate could be adjusted by varying the composition of methyl-bi-acrylic-poly(ϵ-caprolactone-b-poly(ethylene glycol)-b-ϵ-caprolactone) to directly influence the degree of swelling, cross-linking density, and sol content of the elastomer. The controlled rate of bovine serum albumin and recombinant human interleukin 2 release increased with a larger degree of swelling, higher sol content, and lower cross-link density of the elastomers. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide analysis showed good biocompatibility. These results suggest that these new elastomers are potential candidates for carrier materials in controlled, implantable delivery systems for protein drugs and other biomedical applications.
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Affiliation(s)
- Fangyuan Guo
- College of Pharmaceutical Sciences, Zhejiang University of Technology, Hangzhou, China
| | - Wei Zhang
- College of Mechanical Engineering, Zhejiang University of Technology, Hangzhou, China
| | - Xiaohong Pei
- College of Pharmaceutical Sciences, Zhejiang University of Technology, Hangzhou, China
| | - Xia Shen
- College of Pharmaceutical Sciences, Zhejiang University of Technology, Hangzhou, China
| | - Qinying Yan
- College of Pharmaceutical Sciences, Zhejiang University of Technology, Hangzhou, China
| | - Hanbing Li
- College of Pharmaceutical Sciences, Zhejiang University of Technology, Hangzhou, China
| | - Junxian Yun
- College of Chemical Engineering, Zhejiang University of Technology, Hangzhou, China
| | - Gensheng Yang
- College of Pharmaceutical Sciences, Zhejiang University of Technology, Hangzhou, China
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16
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Optimizing novel implant formulations for the prolonged release of biopharmaceuticals using in vitro and in vivo imaging techniques. J Control Release 2016; 235:352-364. [DOI: 10.1016/j.jconrel.2016.06.013] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2016] [Revised: 06/06/2016] [Accepted: 06/07/2016] [Indexed: 11/23/2022]
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17
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Rupnik S, Buwalda S, Dejean S, Bethry A, Garric X, Coudane J, Nottelet B. Redox Reducible and Hydrolytically Degradable PEG-PLA Elastomers as Biomaterial for Temporary Drug-Eluting Medical Devices. Macromol Biosci 2016; 16:1792-1802. [PMID: 27377673 DOI: 10.1002/mabi.201600132] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2016] [Revised: 05/23/2016] [Indexed: 11/06/2022]
Abstract
With the aim to develop biomaterials for temporary medical devices, a series of novel reducible and/or degradable elastomers has been prepared from PLA-b-PEG-b-PLA copolymers photo-crosslinked with diallyl sulfide or pentaerythritol tetrakis(3-mercaptopropionate). Thermal and mechanical properties, including elastic limit and Young modulus, are assessed. Degradation is then evaluated under standard hydrolytic conditions. Reducibility of a selected elastomer is then illustrated using 2-mercaptoethanol or glutathione as reducing agents. The redox-sensitivity of the selected elastomer and the possibility to modulate the degradability are shown. Considering drug-eluting elastomeric devices applications, anti-inflammatory drug ibuprofen loading is illustrated with the two simplest elastomer formulations. A rapid or slow linear release is observed as a function of the low or high molecular weight of the triblock pre-polymers. Finally, the cytocompatibility of the degradable elastomers is assessed with regard to their potential to favor or inhibit L929 murine fibroblasts proliferation as a function of the hydrophilicity/hydrophobicity of the triblock copolymers.
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Affiliation(s)
- Simona Rupnik
- Institute of Biomolecules Max Mousseron (IBMM) UMR 5247, Department of Artificial Biopolymers, CNRS, University of Montpellier, ENSCM. Faculté de Pharmacie 15 avenue Charles Flahault BP14491, 34093, Montpellier CEDEX 5, France
| | - Sytze Buwalda
- Institute of Biomolecules Max Mousseron (IBMM) UMR 5247, Department of Artificial Biopolymers, CNRS, University of Montpellier, ENSCM. Faculté de Pharmacie 15 avenue Charles Flahault BP14491, 34093, Montpellier CEDEX 5, France
| | - Stéphane Dejean
- Institute of Biomolecules Max Mousseron (IBMM) UMR 5247, Department of Artificial Biopolymers, CNRS, University of Montpellier, ENSCM. Faculté de Pharmacie 15 avenue Charles Flahault BP14491, 34093, Montpellier CEDEX 5, France
| | - Audrey Bethry
- Institute of Biomolecules Max Mousseron (IBMM) UMR 5247, Department of Artificial Biopolymers, CNRS, University of Montpellier, ENSCM. Faculté de Pharmacie 15 avenue Charles Flahault BP14491, 34093, Montpellier CEDEX 5, France
| | - Xavier Garric
- Institute of Biomolecules Max Mousseron (IBMM) UMR 5247, Department of Artificial Biopolymers, CNRS, University of Montpellier, ENSCM. Faculté de Pharmacie 15 avenue Charles Flahault BP14491, 34093, Montpellier CEDEX 5, France
| | - Jean Coudane
- Institute of Biomolecules Max Mousseron (IBMM) UMR 5247, Department of Artificial Biopolymers, CNRS, University of Montpellier, ENSCM. Faculté de Pharmacie 15 avenue Charles Flahault BP14491, 34093, Montpellier CEDEX 5, France
| | - Benjamin Nottelet
- Institute of Biomolecules Max Mousseron (IBMM) UMR 5247, Department of Artificial Biopolymers, CNRS, University of Montpellier, ENSCM. Faculté de Pharmacie 15 avenue Charles Flahault BP14491, 34093, Montpellier CEDEX 5, France
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18
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Guo F, Zhang W, Pei X, Shen X, Yan Q, Hong W, Yang G. Synthesis, characterization, and cytotoxicity of star-shaped polyester-based elastomers as controlled release systems for proteins. J Appl Polym Sci 2016. [DOI: 10.1002/app.43393] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- Fangyuan Guo
- College of Pharmaceutical Science; Zhejiang University of Technology; Hangzhou 310014 China
| | - Wei Zhang
- College of Mechanical Engineering; Zhejiang University of Technology; Hangzhou 310014 China
| | - Xiaohong Pei
- College of Pharmaceutical Science; Zhejiang University of Technology; Hangzhou 310014 China
| | - Xia Shen
- College of Pharmaceutical Science; Zhejiang University of Technology; Hangzhou 310014 China
| | - Qinying Yan
- College of Pharmaceutical Science; Zhejiang University of Technology; Hangzhou 310014 China
| | - Weiyong Hong
- Taizhou Municipal Hospital of Zhejiang Province; Taizhou 318000 China
| | - Gensheng Yang
- College of Pharmaceutical Science; Zhejiang University of Technology; Hangzhou 310014 China
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19
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Three-dimensional biomaterial degradation — Material choice, design and extrinsic factor considerations. Biotechnol Adv 2014; 32:984-99. [DOI: 10.1016/j.biotechadv.2014.04.014] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2014] [Revised: 04/18/2014] [Accepted: 04/30/2014] [Indexed: 11/20/2022]
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20
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Babasola IO, Zhang W, Amsden BG. Osmotic pressure driven protein release from viscous liquid, hydrophobic polymers based on 5-ethylene ketal ε-caprolactone: Potential and mechanism. Eur J Pharm Biopharm 2013; 85:765-72. [DOI: 10.1016/j.ejpb.2013.04.009] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2013] [Revised: 04/05/2013] [Accepted: 04/10/2013] [Indexed: 11/16/2022]
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21
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Gilmore L, Rimmer S, McArthur SL, Mittar S, Sun D, MacNeil S. Arginine functionalization of hydrogels for heparin binding--a supramolecular approach to developing a pro-angiogenic biomaterial. Biotechnol Bioeng 2012; 110:296-317. [PMID: 22753043 DOI: 10.1002/bit.24598] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2012] [Revised: 06/18/2012] [Accepted: 06/22/2012] [Indexed: 11/05/2022]
Abstract
Our aim was to synthesize a biomaterial that stimulates angiogenesis for tissue engineering applications by exploiting the ability of heparin to bind and release vascular endothelial growth factor (VEGF). The approach adopted involved modification of a hydrogel with positively charged peptides (oligolysine or oligoarginine) to achieve heparin binding. Precursor hydrogels were produced from copolymerization of N-vinyl pyrolidone, diethylene glycol bis allyl carbonate and acrylic acid (PNDA) and functionalized after activation of the carboxylic acid groups with trilysine or triarginine peptides (PNDKKK and PNDRRR). Both hydrogels were shown to bind and release bioactive VEGF165 with arginine-modified hydrogel outperforming the lysine-modified hydrogel. Cytocompatibility of the hydrogels was confirmed in vitro with primary human dermal fibroblasts and human dermal microvascular endothelial cells (HUDMECs). Proliferation of HUDMECs was stimulated by triarginine-functionalized hydrogels, and to a lesser extent by lysine functionalized hydrogels once loaded with heparin and VEGF. The data suggests that heparin-binding hydrogels provide a promising approach to a pro-angiogenic biomaterial.
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Affiliation(s)
- Louisa Gilmore
- Department of Chemistry, University of Sheffield, Sheffield S3 7HF, UK
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22
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Liu Q, Jiang L, Shi R, Zhang L. Synthesis, preparation, in vitro degradation, and application of novel degradable bioelastomers—A review. Prog Polym Sci 2012. [DOI: 10.1016/j.progpolymsci.2011.11.001] [Citation(s) in RCA: 127] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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23
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Chapanian R, Tse MY, Pang SC, Amsden BG. Osmotic Release of Bioactive VEGF from Biodegradable Elastomer Monoliths is the Same In Vivo As In Vitro. J Pharm Sci 2012; 101:588-97. [DOI: 10.1002/jps.22782] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2011] [Revised: 02/14/2011] [Accepted: 09/16/2011] [Indexed: 11/06/2022]
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24
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Harrane A, Leroy A, Nouailhas H, Garric X, Coudane J, Nottelet B. PLA-based biodegradable and tunable soft elastomers for biomedical applications. Biomed Mater 2011; 6:065006. [DOI: 10.1088/1748-6041/6/6/065006] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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25
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Strobel C, Bormann N, Kadow-Romacker A, Schmidmaier G, Wildemann B. Sequential release kinetics of two (gentamicin and BMP-2) or three (gentamicin, IGF-I and BMP-2) substances from a one-component polymeric coating on implants. J Control Release 2011; 156:37-45. [DOI: 10.1016/j.jconrel.2011.07.006] [Citation(s) in RCA: 69] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2011] [Revised: 06/22/2011] [Accepted: 07/03/2011] [Indexed: 01/22/2023]
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26
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The three-dimensional vascularization of growth factor-releasing hybrid scaffold of poly (epsilon-caprolactone)/collagen fibers and hyaluronic acid hydrogel. Biomaterials 2011; 32:8108-17. [PMID: 21807407 DOI: 10.1016/j.biomaterials.2011.07.022] [Citation(s) in RCA: 130] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2011] [Accepted: 07/08/2011] [Indexed: 01/04/2023]
Abstract
A significant stumbling block in the creation of functional three-dimensional (3D) engineered tissues is the proper vascularization of the constructs. Furthermore, in the context of electrospinning, the development of 3D constructs using this technique has been hindered by the limited infiltration of cells into their structure. In an attempt to address these issues, a hybrid mesh of poly (ɛ-caprolactone)-collagen blend (PCL/Col) and hyaluronic acid (HA) hydrogel, Heprasil™ was created via a dual electrodeposition system. Simultaneous deposition of HA and PCL/Col allowed the dual loading and controlled release of two potent angiogenic growth factors VEGF(165) and PDGF-BB over a period of five weeks in vitro. Furthermore, this manner of loading sustained the bioactivity of the two growth factors. Utilizing an in-house developed 3D co-culture assay model of human umbilical vein endothelial cells and lung fibroblasts, the growth factor-loaded hybrid meshes was shown to not only support cellular attachment, but also their infiltration and the recapitulation of primitive capillary network in the scaffold's architecture. Thus, the creation of a PCL/Col-Heprasil hybrid scaffold is a step forward toward the attainment of a 3D bio-functionalized, vascularized tissue engineering construct.
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27
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Amsden BG. Delivery approaches for angiogenic growth factors in the treatment of ischemic conditions. Expert Opin Drug Deliv 2011; 8:873-90. [DOI: 10.1517/17425247.2011.577412] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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28
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Regulation of proxyphylline's release from silicone rubber matrices by the use of osmotically active excipients and a multi-layer system. Int J Pharm 2011; 408:120-9. [DOI: 10.1016/j.ijpharm.2011.02.018] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2010] [Revised: 01/12/2011] [Accepted: 02/09/2011] [Indexed: 11/24/2022]
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29
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King WJ, Toepke MW, Murphy WL. Facile formation of dynamic hydrogel microspheres for triggered growth factor delivery. Acta Biomater 2011; 7:975-85. [PMID: 21029793 DOI: 10.1016/j.actbio.2010.10.026] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2010] [Revised: 10/11/2010] [Accepted: 10/22/2010] [Indexed: 11/25/2022]
Abstract
Dynamic hydrogels have emerged as an important class of biomaterials for temporal control over growth factor delivery. In this study we formed dynamic hydrogel microspheres from protein-polymer conjugates using an aqueous two-phase suspension polymerization process. This polymerization process enabled rapid microsphere formation without the use of an organic phase, surfactants, mechanical strain or toxic radical initiators. The microspheres' size distribution was modulated by varying the protein-polymer conformation in the pre-polymer solution. Notably, the protein's ligand-induced, nanometer-scale conformational change translated to maximum hydrogel volume changes of 76±10%. The magnitude of the microspheres' volume change was tuned by varying the crosslinking time and ligand identity. After characterizing the microspheres' dynamic properties, we encapsulated two important therapeutic proteins, vascular endothelial growth factor (VEGF) and bone morphogenetic protein-2 (BMP-2), in the hydrogel microspheres and characterized how the microspheres' dynamic properties controlled their release. Significantly, the aqueous two-phase suspension polymerization process enabled high encapsulation efficiencies (65.8±4.8% and 79.5±3.0% for VEGF and BMP-2, respectively). Also, the microspheres' ligand-induced volume change triggered VEGF and BMP-2 release at specific, predetermined times. There are hundreds of proteins that undergo well-characterized conformational changes that could be processed into hydrogel microspheres via aqueous two-phase suspension polymerizations. Therefore, this approach could be used to form dynamic, growth-factor-releasing hydrogel microspheres that respond to a broad range of specific biochemical ligands.
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30
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Nelson DM, Baraniak PR, Ma Z, Guan J, Mason NS, Wagner WR. Controlled release of IGF-1 and HGF from a biodegradable polyurethane scaffold. Pharm Res 2011; 28:1282-93. [PMID: 21347565 DOI: 10.1007/s11095-011-0391-z] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2010] [Accepted: 02/03/2011] [Indexed: 12/13/2022]
Abstract
PURPOSE Biodegradable elastomers, which can possess favorable mechanical properties and degradation rates for soft tissue engineering applications, are more recently being explored as depots for biomolecule delivery. The objective of this study was to synthesize and process biodegradable, elastomeric poly(ester urethane)urea (PEUU) scaffolds and to characterize their ability to incorporate and release bioactive insulin-like growth factor-1 (IGF-1) and hepatocyte growth factor (HGF). METHODS Porous PEUU scaffolds made from either 5 or 8 wt% PEUU were prepared with direct growth-factor incorporation. Long-term in vitro IGF-1 release kinetics were investigated in saline or saline with 100 units/ml lipase to simulate in vivo degradation. Cellular assays were used to confirm released IGF-1 and HGF bioactivity. RESULTS IGF-1 release into saline occurred in a complex multi-phasic manner for up to 440 days. Scaffolds generated from 5 wt% PEUU delivered protein faster than 8 wt% scaffolds. Lipase-accelerated scaffold degradation led to delivery of >90% protein over 9 weeks for both polymer concentrations. IGF-1 and HGF bioactivity in the first 3 weeks was confirmed. CONCLUSIONS The capacity of a biodegradable elastomeric scaffold to provide long-term growth-factor delivery was demonstrated. Such a system might provide functional benefit in cardiovascular and other soft tissue engineering applications.
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Affiliation(s)
- Devin M Nelson
- Department of Bioengineering, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
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31
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Tobias IS, Lee H, Engelmayr GC, Macaya D, Bettinger CJ, Cima MJ. Zero-order controlled release of ciprofloxacin-HCl from a reservoir-based, bioresorbable and elastomeric device. J Control Release 2010; 146:356-62. [PMID: 20566343 PMCID: PMC2934741 DOI: 10.1016/j.jconrel.2010.05.036] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2010] [Accepted: 05/28/2010] [Indexed: 01/09/2023]
Abstract
A reservoir-based device constructed of a completely biodegradable elastomer can enable several new implantation and insertion options for localized drug therapy, particularly in the case of urological therapies. We performed an in vitro performance evaluation of an implantable, bio-resorbable device that supplies short-term controlled release of ciprofloxacin-HCl (CIP). The proposed device functions through a combination of osmosis and diffusion mechanisms to release CIP for short-term therapies of a few weeks duration. Poly(glycerol-co-sebacic acid) (PGS) was cast in a tubular geometry with solid drug powder packed into its core and a micro-machined release orifice drilled through its wall. Drug release experiments were performed to determine the effective release rate from a single orifice and the range of orifice sizes in which controlled zero-order release was the main form of drug expulsion from the device. It is demonstrated that PGS is sufficiently permeable to water to allow the design of an elementary osmotic pump for drug delivery. Indeed, PGS's water permeability is several orders of magnitude larger than commonly used cellulose acetate for elementary osmotic pumps.
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Affiliation(s)
- Irene S. Tobias
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Heejin Lee
- Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - George C. Engelmayr
- Harvard-M.I.T. Division of Health Sciences and Technology, Cambridge, MA 02139, USA
| | - Daniel Macaya
- Department of Materials Science and Engineering, Cornell University, Ithaca, NY 14850, USA
| | - Christopher J. Bettinger
- Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Michael J. Cima
- Convergence Products Research Laboratory, Department of Materials Science & Engineering, Koch Institute of Integrative Cancer Research, Massachusetts Institute of Technology, 77 Massachusetts Ave., Rm 12-011, Cambridge, MA 02139, USA
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32
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Jarvis KL, Barnes TJ, Prestidge CA. Thermal oxidation for controlling protein interactions with porous silicon. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2010; 26:14316-14322. [PMID: 20684558 DOI: 10.1021/la102367z] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Thermal oxidation of porous silicon (pSi) has been used to control interactions with three proteins; lysozyme, papain, and human serum albumin (HSA) enabling the influences of protein structure, molecular weight, and charge to be elucidated. Adsorption behavior was assessed via adsorption isotherms while the structures of adsorbed proteins were investigated using a bioactivity assay, FTIR, and zeta potential. Time-of-flight secondary ion mass spectrometry was used to examine protein pore penetration. High protein adsorption onto unoxidized pSi (240-610 microg/m(2)) was attributed to predominately hydrophobic interactions which resulted in structural changes of the adsorbed proteins and significant loss of bioactivity. Thermal oxidation at 400 and 800 degrees C significantly reduced protein adsorption (80-485 microg/m(2)) by reducing hydrophobicity. Oxidation of pSi modified the protein adsorption mechanisms to solely electrostatic attraction for positively charged proteins and structural rearrangement for negatively charged proteins. Adsorption via electrostatic attraction preserved protein bioactivity and zeta potential, thus inferring a retention of their native structure. In contrast, the negative charge and globular structure of HSA resulted in a loss of structure. We have demonstrated that thermal oxidation of pSi can be used to control protein interactions, adsorbed structure, and bioactivity.
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Affiliation(s)
- Karyn L Jarvis
- Ian Wark Research Institute, Australian Research Council Special Research Centre for Particle and Material Interfaces, University of South Australia, Mawson Lakes SA 5095, Australia
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33
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Amsden BG, Timbart L, Marecak D, Chapanian R, Tse MY, Pang SC. VEGF-induced angiogenesis following localized delivery via injectable, low viscosity poly(trimethylene carbonate). J Control Release 2010; 145:109-15. [DOI: 10.1016/j.jconrel.2010.03.029] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2010] [Revised: 03/09/2010] [Accepted: 03/30/2010] [Indexed: 10/19/2022]
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34
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Shaker MA, Doré JJE, Younes HM. Synthesis, characterization and cytocompatibility of a poly(diol-tricarballylate) visible light photo-cross-linked biodegradable elastomer. JOURNAL OF BIOMATERIALS SCIENCE-POLYMER EDITION 2010; 21:507-28. [PMID: 20233506 DOI: 10.1163/156856209x429157] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The synthesis, characterization and in vitro cytocompatibility of a new family of photo-cross-linked amorphous poly(diol-tricarballylate) (PDT) biodegradable elastomeric polyesters are reported. The synthesis was based on the polycondensation reaction between tricarballylic acid and alkylene diols, followed by acrylation. The prepared and acrylated poly(diol-tricarballylate) (APDT) was characterized by means of FT-IR, (1)H-NMR, GPC and DSC. Liquid-to-solid photo-curing was carried out by exposing the APDT to visible light in the presence of camphorquinone as a photoinitiator. The thermal properties, mechanical characteristics, sol content, long-term in vitro degradation and cytocompatibility of the prepared PDT elastomers were also reported. The mechanical and degradation properties of this new photocurable elastomer can be precisely controlled by varying the density of acrylate moieties in the matrix of the polymer, and through changes in the pre-polymer chain length. The use of visible light cross-linking, possibility of solventless drug loading, controllable mechanical properties and cytocompatibility of these new elastomers make them excellent candidates for use in controlled implantable drug-delivery systems of protein drugs and other biomedical applications.
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Affiliation(s)
- Mohamed A Shaker
- School of Pharmacy, Memorial University of Newfoundland, St. John's, NF, Canada
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35
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Amsden B, Qi B. Anti-atherosclerotic peptide delivery from a photocrosslinkable biodegradable network. Int J Pharm 2010; 388:32-9. [DOI: 10.1016/j.ijpharm.2009.12.030] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2009] [Revised: 12/03/2009] [Accepted: 12/10/2009] [Indexed: 11/17/2022]
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36
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Tissue Response to, and Degradation Rate of, Photocrosslinked Trimethylene Carbonate-Based Elastomers Following Intramuscular Implantation. MATERIALS 2010. [PMCID: PMC5513461 DOI: 10.3390/ma3021156] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Cylindrical elastomers were prepared through the UV-initiated crosslinking of terminally acrylated, 8,000 Da star-poly(trimethylene carbonate-co-ε-caprolactone) and star-poly(trimethylene carbonate-co-d,l-lactide). These elastomers were implanted intramuscularly into the hind legs of male Wistar rats to determine the influence of the comonomer on the weight loss, tissue response, and change in mechanical properties of the elastomer. The elastomers exhibited only a mild inflammatory response that subsided after the first week; the response was greater for the stiffer d,l-lactide-containing elastomers. The elastomers exhibited weight loss and sol content changes consistent with a bulk degradation mechanism. The d,l-lactide-containing elastomers displayed a nearly zero-order change in Young’s modulus and stress at break over the 30 week degradation time, while the ε-caprolactone-containing elastomers exhibited little change in modulus or stress at break.
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37
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Shaker MA, Younes HM. Interleukin-2: Evaluation of Routes of Administration and Current Delivery Systems in Cancer Therapy. J Pharm Sci 2009; 98:2268-98. [DOI: 10.1002/jps.21596] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
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38
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De la Riva B, Nowak C, Sánchez E, Hernández A, Schulz-Siegmund M, Pec MK, Delgado A, Evora C. VEGF-controlled release within a bone defect from alginate/chitosan/PLA-H scaffolds. Eur J Pharm Biopharm 2009; 73:50-8. [PMID: 19442724 DOI: 10.1016/j.ejpb.2009.04.014] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2008] [Revised: 04/20/2009] [Accepted: 04/28/2009] [Indexed: 01/12/2023]
Abstract
VEGF and its receptors constitute the key signaling system for angiogenic activity in tissue formation, but a direct implication of the growth factor in the recruitment, survival and activity of bone forming cells has also emerged. For this reason, we developed a composite (alginate/chitosan/PLA-H) system that controls the release kinetics of incorporated VEGF to enhance neovascularization in bone healing. VEGF release kinetics and tissue distribution were determined using iodinated ((125)I) growth factor. VEGF was firstly encapsulated in alginate microspheres. To reduce the high in vitro burst release, the microspheres were included in scaffolds. Matrices were prepared with alginate (A-1, A-2), chitosan (CH-1, CH-2) or by coating the CH-1 matrix with a PLA-H (30 kDa) film (CH-1-PLA), the latter one optimally reducing the in vitro and in vivo burst effect. The VEGF in vitro release profile from CH-1-PLA was characterized by a 13% release within the first 24h followed by a constant release rate throughout 5 weeks. For VEGF released from composite scaffolds in vitro, bioactivity was maintained above 90% of the expected value. Despite the fact that the in vivo release rate was slightly faster, a good in vitro-in vivo correlation was found. The VEGF released from CH-1 and CH-1-PLA matrices implanted into the femurs of rats remained located around the implantation site with a negligible systemic exposure. These scaffolds provided a bone local GF concentration above 10 ng/g during 2 and 5 weeks, respectively, in accordance to the in vivo release kinetics. Our data show that the incorporation of VEGF into the present scaffolds allows for a controlled release rate and localization of the GF within the bone defect.
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Affiliation(s)
- Beatriz De la Riva
- Department of Chemical Engineering and Pharmaceutical Technology, University of La Laguna, La Laguna, Spain
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Nishikawa M, Hashida M, Takakura Y. Catalase delivery for inhibiting ROS-mediated tissue injury and tumor metastasis. Adv Drug Deliv Rev 2009; 61:319-26. [PMID: 19385054 DOI: 10.1016/j.addr.2009.01.001] [Citation(s) in RCA: 128] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Reactive oxygen species (ROS) have been suggested to be involved in a variety of human diseases. Catalase, an enzyme degrading hydrogen peroxide, can be used as a therapeutic agent for such diseases, but its successful application will depend on the distribution of the enzyme to the sites where ROS are generated. Chemical modification techniques have been used to control the tissue distribution of catalase, and delivery to hepatocytes (galactosylation), liver nonparenchymal cells (mannosylation or succinylation), kidney (cationization) and the blood pool (PEGylation) has been achieved. The effectiveness of catalase delivery has been demonstrated in animal models for hepatic ischemia/reperfusion injury, chemical-induced tissue injuries and tumor metastasis to the liver, lung and peritoneal organs. Significant inhibition was observed in the ROS-mediated oxidative tissue damages and ROS-mediated upregulation of expression of genes responsible for recruitment of inflammatory cells and for metastatic growth of tumor cells. Because oxygen plays a fundamental key role in our life and oxidative stress is implicated in a wide variety of human diseases, catalase delivery could have wide application in the near future.
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Jay SM, Saltzman WM. Controlled delivery of VEGF via modulation of alginate microparticle ionic crosslinking. J Control Release 2009; 134:26-34. [PMID: 19027807 PMCID: PMC2678414 DOI: 10.1016/j.jconrel.2008.10.019] [Citation(s) in RCA: 129] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2008] [Revised: 10/10/2008] [Accepted: 10/30/2008] [Indexed: 12/25/2022]
Abstract
Clinical application of therapeutic angiogenesis is hampered by a lack of viable systems that demonstrate controlled, sustained release of vascular endothelial growth factor (VEGF). Alginate has emerged as a popular material for VEGF delivery; however most alginate-based systems offer limited means to control the rate of VEGF release beyond reducing the VEGF:alginate ratio to suboptimal efficiency. This study describes methods to control the release of VEGF from small (<10 microm mean diameter) alginate microparticles via the use of different ionic crosslinkers. Crosslinking with Zn(2+) versus Ca(2+) reduced VEGF diffusional release and the combination of discrete populations of either Zn(2+)- or Ca(2+)-crosslinked particles allowed for control over the sustained release profiles for VEGF. The particle preparations were non-toxic and VEGF was bioactive after release. These results demonstrate that ionic modulation of alginate crosslinking is a viable strategy for controlling release of VEGF while retaining the high protein:polymer ratio that makes alginate an attractive carrier for delivery of protein therapeutics.
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Affiliation(s)
- Steven M. Jay
- Department of Biomedical Engineering, Interdepartmental Program in Vascular Biology and Therapeutics, Yale University, New Haven, CT 06520 USA
| | - W. Mark Saltzman
- Department of Biomedical Engineering, Interdepartmental Program in Vascular Biology and Therapeutics, Yale University, New Haven, CT 06520 USA
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Chapanian R, Tse MY, Pang SC, Amsden BG. Long termin vivodegradation and tissue response to photo-cross-linked elastomers prepared from star-shaped prepolymers of poly(ε-caprolactone-co-D,L-lactide). J Biomed Mater Res A 2009; 92:830-42. [DOI: 10.1002/jbm.a.32422] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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42
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Kenneth Ward W. A review of the foreign-body response to subcutaneously-implanted devices: the role of macrophages and cytokines in biofouling and fibrosis. J Diabetes Sci Technol 2008; 2:768-77. [PMID: 19885259 PMCID: PMC2769792 DOI: 10.1177/193229680800200504] [Citation(s) in RCA: 209] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The biological response to implanted biomaterials in mammals is a complex series of events that involves many biochemical pathways. Shortly after implantation, fibrinogen and other proteins bind to the device surface, a process known as biofouling. Macrophages then bind to receptors on the proteins, join into multinucleated giant cells, and release transforming growth factor beta and other inflammatory cytokines. In response to these signals, quiescent fibroblasts are transformed into myofibroblasts, which synthesize procollagen via activation of Smad mediators. The procollagen becomes crosslinked after secretion into the extracellular space. Mature crosslinked collagen and other extracellular matrix proteins gradually contribute to formation of a hypocellular dense fibrous capsule that becomes impermeable or hypopermeable to many compounds. Porous substrates and angiogenic growth factors can stimulate formation of microvessels, which to some extent can maintain analyte delivery to implanted sensors. However, stimulation by vascular endothelial growth factor alone may lead to formation of leaky, thin-walled, immature vessels. Other growth factors are most probably needed to act upon these immature structures to create more robust vessels.During implantation of foreign bodies, the foreign-body response is difficult to overcome, and thousands of biomaterials have been tested. Biomimicry (i.e., creating membranes whose chemical structure mimics natural cellular compounds) may diminish the response, but as of this writing, it has not been possible to create a stealth material that circumvents the ability of the mammalian surveillance systems to distinguish foreign from self.
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Affiliation(s)
- W Kenneth Ward
- Legacy Clinical Research and Technology Center and Oregon Health and Science University, Portland, Oregon, USA.
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Abstract
BACKGROUND Biodegradable elastomers have been used in many different manners for controlled drug delivery. The development of new biodegradable elastomers has recently increased, driven mainly by tissue engineering research. OBJECTIVE This review outlines the different uses of biodegradable elastomers in controlled release. METHODS This review was limited to those papers wherein the polymer chosen as the delivery vehicle was demonstrably elastomeric. CONCLUSION Biodegradable elastomers have an established role in controlled release and an expanding role in combination scaffolds providing controlled release and mechanical stimulation capability for tissue regeneration/engineering.
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Affiliation(s)
- Brian G Amsden
- Queen's University, Department of Chemical Engineering, Kingston, Ontario, Canada.
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Amsden B, Misra G, Marshall M, Turner N. Synthesis and Characterization of Biodegradable Networks Providing Saturated-Solution Prolonged Delivery. J Pharm Sci 2008; 97:860-74. [PMID: 17701973 DOI: 10.1002/jps.21023] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Numerous peptide drugs require continuous and local delivery to obtain optimum therapeutic effect. Herein, we describe the incorporation of a model peptide drug, vitamin B12, as well as goserelin acetate, in biodegradable elastomer cylinders through photo-cross-linking. The elastomer was prepared from acrylated star-poly(epsilon-caprolactone-co-D,L-lactide). Release was manipulated through the incorporation of poly(ethylene glycol) diacrylate (PEGD) into the network at concentrations up to 30% (w/w). The PEGD in the network caused rapid swelling that remained constant throughout the release period. The degree of swelling was low, ranging from 10 to 45% (w/w), and increasing as the PEGD content increased. Release proceeded with a minimal initial burst, and extended periods of nearly constant release, ranging from approximately 5 to 70% mass fraction released, were obtained. The release rate was independent of particle size and increased as the cylinder diameter decreased, as the amount of PEGD increased, as the molecular weight of PEGD increased, and as the agent loading increased. Moreover, goserelin acetate, which has a comparable diffusivity but greater aqueous solubility, was released at a greater rate than vitamin B12. This release behavior is explained as a balance between agent dissolution in the swollen polymer matrix and diffusion through the polymer matrix bulk.
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Affiliation(s)
- Brian Amsden
- Department of Chemical Engineering, Queen's University, Kingston, Ontario, Canada K7L 3N6.
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Amsden B. Curable, biodegradable elastomers: emerging biomaterials for drug delivery and tissue engineering. SOFT MATTER 2007; 3:1335-1348. [PMID: 32900112 DOI: 10.1039/b707472g] [Citation(s) in RCA: 117] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Biodegradable elastomers have a number of potential applications in the biomedical area, especially in the emerging field of soft-tissue engineering where the mechanical properties of the polymer scaffold should match those of the tissue to be grown. An increasing number of synthesis strategies have been employed in order to prepare such elastomers. In this review, these synthesis strategies and the properties of these elastomers are outlined. The factors that influence the characteristics of these elastomers including mechanical properties, degradation rate, and mechanical property change during degradation, are discussed in terms of the design of the elastomer and their advantages and disadvantages for the biomedical applications considered.
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Affiliation(s)
- Brian Amsden
- Department of Chemical Engineering, Queen's University, Kingston, ON, Canada.
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Snider C, Lee SY, Yeo Y, Grégori GJ, Robinson JP, Park K. Microenvironment-Controlled Encapsulation (MiCE) Process: Effects of PLGA Concentration, Flow Rate, and Collection Method on Microcapsule Size and Morphology. Pharm Res 2007; 25:5-15. [PMID: 17914663 DOI: 10.1007/s11095-007-9456-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2007] [Accepted: 09/06/2007] [Indexed: 11/30/2022]
Abstract
PURPOSE To evaluate the real-time effects of formulation and instrumental variables on microcapsule formation via natural jet segmentation, a new microencapsulation system termed the microenvironment-controlled encapsulation (MiCE) process was developed. METHODS A modified flow cytometer nozzle hydrodynamically focuses an inner drug and outer polymer solution emanating from a coaxial needle assembly into a two-layer compound jet. Poly(lactic-co-glycolic acid) (PLGA) dissolved in a water-miscible organic solvent resulted in formation of reservoir-type microcapsules by interfacial phase separation induced at the boundary between the PLGA solution and aqueous sheath. RESULTS The MiCE process produced microcapsules with mean diameters ranging from 15-25 microm. The resultant microcapsule size distribution and number of drug cores existing within each microcapsule was largely influenced by the PLGA concentration and microcapsule collection method. Higher PLGA concentrations yielded higher mean diameters of single-core microcapsules. Higher drug solution flow rates increased the core size, while higher PLGA solution flow rates increased the PLGA film thickness. CONCLUSION The MiCE microencapsulation process allows effective monitoring and control of the instrumental parameters affecting microcapsule production. However, the microcapsule collection method in this process needs to be further optimized to obtain microcapsules with desired morphologies, precise membrane thicknesses, high encapsulation efficiencies, and tight size distributions.
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Affiliation(s)
- Connie Snider
- Department of Pharmaceutics, Purdue University, West Lafayette, IN 47907, USA
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