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Van Hecke M, Van Hoof L, Sikole M, Mufty H, Claus P, Verbrugghe P, Ely J, Berg GA, Roskams T, Meuris B. A Large-Diameter Vascular Graft Replacing Animal-Derived Sealants With an Elastomeric Polymer. J Surg Res 2023; 284:6-16. [PMID: 36527768 DOI: 10.1016/j.jss.2022.11.041] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2022] [Revised: 10/25/2022] [Accepted: 11/20/2022] [Indexed: 12/16/2022]
Abstract
INTRODUCTION To assess the safety and efficacy of an experimental large-diameter vascular graft externally sealed with an elastomeric polymer when used as an interposition graft in the descending aorta of sheep. METHODS The experimental vascular grafts as well as control gelatin sealed interposition grafts were inserted into the descending aorta of juvenile sheep. The grafts were assessed by time to hemostasis and blood loss during surgery and hematology and biochemistry panels at distinct time points. Magnetic resonance imaging (MRI) was performed at 3 and at 6 mo after surgery, after which the animals were euthanized and necropsies were carried out including macroscopic and microscopic examination of the grafts, anastomoses, and distal organs. RESULTS All animals survived the study period. There was no perceivable difference in the surgical handling of the grafts. The median intraoperative blood loss was 27.5 mL (range 10.0-125.0 mL) in the experimental group and 50.0 mL (range 10.0-75.0 mL) in the control group. The median time to hemostasis was 5.0 min (range 2.0-16.0 min) minutes in the experimental group versus 6.0 min (range 4.0-6.0 min) in the control group. MRI showed normal flow and graft patency in both groups. Healing and perianastomotic endothelialization was similar in both groups. CONCLUSIONS The experimental graft has a similar safety and performance profile and largely comparable necropsy results, in comparison to a commonly used prosthetic vascular graft, with the experimental grafts eliciting a nonadherent external fibrous capsule as the major difference compared to the control grafts that were incorporated into the periadventitia. Survival, hemostatic sealing, and hematologic and radiologic results were comparable between the study groups.
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Affiliation(s)
- Manon Van Hecke
- Department of Pathology, University Hospitals Leuven, Leuven, Belgium.
| | - Lucas Van Hoof
- Department of Cardiac Surgery, University Hospitals Leuven, Leuven, Belgium
| | - Magdalena Sikole
- Department of Cardiac Surgery, University Hospitals Leuven, Leuven, Belgium
| | - Hozan Mufty
- Department of Vascular Surgery, University Hospitals Leuven, Leuven, Belgium
| | - Piet Claus
- KU Leuven, Department of Cardiovascular Sciences, Cardiovascular Imaging and Dynamics, Leuven, Belgium
| | - Peter Verbrugghe
- Department of Cardiac Surgery, University Hospitals Leuven, Leuven, Belgium
| | - John Ely
- RUA Life Sciences, Irvine, United Kingdom
| | | | - Tania Roskams
- Department of Pathology, University Hospitals Leuven, Leuven, Belgium
| | - Bart Meuris
- Department of Cardiac Surgery, University Hospitals Leuven, Leuven, Belgium
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2
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Wu H, Dai T, Ao W, Shao S, Li Z, Luo F, Li J, Zhao D, Lan W, Zhang H, Tan H. The role of segmental mixing on the mechanical properties and oxidative stability of polydimethylsiloxane-based polyetherurethane. POLYMER 2022. [DOI: 10.1016/j.polymer.2022.125401] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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3
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Fathi-Karkan S, Banimohamad-Shotorbani B, Saghati S, Rahbarghazi R, Davaran S. A critical review of fibrous polyurethane-based vascular tissue engineering scaffolds. J Biol Eng 2022; 16:6. [PMID: 35331305 PMCID: PMC8951709 DOI: 10.1186/s13036-022-00286-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2021] [Accepted: 03/08/2022] [Indexed: 12/20/2022] Open
Abstract
Certain polymeric materials such as polyurethanes (PUs) are the most prevalent class of used biomaterials in regenerative medicine and have been widely explored as vascular substitutes in several animal models. It is thought that PU-based biomaterials possess suitable hemo-compatibility with comparable performance related to the normal blood vessels. Despite these advantages, the possibility of thrombus formation and restenosis limits their application as artificial functional vessels. In this regard, various surface modification approaches have been developed to enhance both hemo-compatibility and prolong patency. While critically reviewing the recent advances in vascular tissue engineering, mainly PU grafts, this paper summarizes the application of preferred cell sources to vascular regeneration, physicochemical properties, and some possible degradation mechanisms of PU to provide a more extensive perspective for future research.
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Affiliation(s)
- Sonia Fathi-Karkan
- Student Research Committee, Tabriz University of Medical Sciences, Tabriz, Iran.,Department of Medical Nanotechnology, Faculty of Advanced Medical Science, Tabriz University of Medical Sciences, Golgasht St, Tabriz, Iran.,Drug Applied Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Behnaz Banimohamad-Shotorbani
- Drug Applied Research Center, Tabriz University of Medical Sciences, Tabriz, Iran.,Department of Tissue Engineering, Faculty of Advanced Medical Sciences, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Sepideh Saghati
- Department of Tissue Engineering, Faculty of Advanced Medical Sciences, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Reza Rahbarghazi
- Student Research Committee, Tabriz University of Medical Sciences, Tabriz, Iran. .,Stem Cell Research Center, Tabriz University of Medical Sciences, Tabriz, Iran. .,Department of Applied Cell Sciences, Faculty of Advanced Medical Sciences, Tabriz University of Medical Sciences, Tabriz, Iran.
| | - Soodabeh Davaran
- Student Research Committee, Tabriz University of Medical Sciences, Tabriz, Iran.
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4
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Ma J, Deng B, Fan Y, Huang X, Chen D, Ma Y, Chen H, Grzesiak AL, Feng S. Polyurethane elastomers with amphiphilic ABA tri-block co-polymers as the soft segments showing record-high tensile strength and simultaneously increased ductility. Polym Chem 2022. [DOI: 10.1039/d2py00752e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Polyurethane elastomers with amphiphilic ABA tri-block co-polymers as the soft segments robustly show record-high tensile strength and simultaneously increased ductility via producing small and uniform hard domains.
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Affiliation(s)
- Jun Ma
- The State Key Laboratory of Molecular Engineering of Polymers and Department of Macromolecular Science, Fudan University, 2005 Songhu Road, Shanghai 200438, China
| | - Baixue Deng
- The State Key Laboratory of Molecular Engineering of Polymers and Department of Macromolecular Science, Fudan University, 2005 Songhu Road, Shanghai 200438, China
| | - Yanbin Fan
- The Dow Chemical Company, 936 Zhangheng Road, Shanghai 201203, China
| | - Xiayun Huang
- The State Key Laboratory of Molecular Engineering of Polymers and Department of Macromolecular Science, Fudan University, 2005 Songhu Road, Shanghai 200438, China
| | - Daoyong Chen
- The State Key Laboratory of Molecular Engineering of Polymers and Department of Macromolecular Science, Fudan University, 2005 Songhu Road, Shanghai 200438, China
| | - Yan Ma
- The Dow Chemical Company, 936 Zhangheng Road, Shanghai 201203, China
| | - Hongyu Chen
- The Dow Chemical Company, 936 Zhangheng Road, Shanghai 201203, China
| | - Adam L. Grzesiak
- The Dow Chemical Company, 693 Washington Street, Midland, Michigan 48640, USA
| | - Shaoguang Feng
- The Dow Chemical Company, 936 Zhangheng Road, Shanghai 201203, China
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5
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Zhen L, Creason SA, Simonovsky FI, Snyder JM, Lindhartsen SL, Mecwan MM, Johnson BW, Himmelfarb J, Ratner BD. Precision-porous polyurethane elastomers engineered for application in pro-healing vascular grafts: Synthesis, fabrication and detailed biocompatibility assessment. Biomaterials 2021; 279:121174. [PMID: 34715636 DOI: 10.1016/j.biomaterials.2021.121174] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2021] [Accepted: 08/16/2021] [Indexed: 01/22/2023]
Abstract
Unmet needs for small diameter, non-biologic vascular grafts and the less-than-ideal performance of medium diameter grafts suggest opportunities for major improvements. Biomaterials that are mechanically matched to native blood vessels, reduce the foreign body capsule (FBC) and demonstrate improved integration and healing are expected to improve graft performance. In this study, we developed biostable, crosslinked polyurethane formulations and used them to fabricate scaffolds with precision-engineered 40 μm pores. We matched the scaffold mechanical properties with those of native blood vessels by optimizing the polyurethane compositions. We hypothesized that such scaffolds promote healing and mitigate the FBC. To test our hypothesis, polyurethanes with 40 μm pores, 100 μm pores, and non-porous slabs were implanted subcutaneously in mice for 3 weeks, and then were examined histologically. Our results show that 40 μm porous scaffolds elicit the highest level of angiogenesis, cellularization, and the least severe foreign body capsule (based on a refined assessment method). This study presents the first biomaterial with tuned mechanical properties and a precision engineered porous structure optimized for healing, thus can be ideal for pro-healing vascular grafts and in situ vascular engineering. In addition, these scaffolds may have wide applications in tissue engineering, drug delivery, and implantable device.
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Affiliation(s)
- Le Zhen
- Department of Chemical Engineering, University of Washington, Seattle, WA, 98195, USA; Department of Bioengineering, University of Washington, Seattle, WA, 98195, USA
| | - Sharon A Creason
- Department of Bioengineering, University of Washington, Seattle, WA, 98195, USA
| | - Felix I Simonovsky
- Department of Bioengineering, University of Washington, Seattle, WA, 98195, USA
| | - Jessica M Snyder
- Department of Comparative Medicine, University of Washington, Seattle, WA, 98195, USA
| | - Sarah L Lindhartsen
- Histology and Imaging Core, University of Washington, Seattle, WA, 98195, USA
| | - Marvin M Mecwan
- Department of Bioengineering, University of Washington, Seattle, WA, 98195, USA
| | - Brian W Johnson
- Histology and Imaging Core, University of Washington, Seattle, WA, 98195, USA
| | - Jonathan Himmelfarb
- Department of Bioengineering, University of Washington, Seattle, WA, 98195, USA; Department of Medicine, Division of Nephrology, University of Washington, Seattle, WA, 98195, USA; Kidney Research Institute, Seattle, WA, 98104, USA; Center for Dialysis Innovation, University of Washington, WA, 98195, USA
| | - Buddy D Ratner
- Department of Chemical Engineering, University of Washington, Seattle, WA, 98195, USA; Department of Bioengineering, University of Washington, Seattle, WA, 98195, USA; Center for Dialysis Innovation, University of Washington, WA, 98195, USA.
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6
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Nurhamiyah Y, Irvine G, Themistou E, Chen B. Novel Biobased Polyamide Thermoplastic Elastomer with Medium Hardness. MACROMOL CHEM PHYS 2021. [DOI: 10.1002/macp.202100218] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Yeyen Nurhamiyah
- School of Mechanical and Aerospace Engineering Queen's University Belfast Stranmillis Road, Belfast BT9 5AH UK
- Research Center for Biomaterials Indonesian Institute of Sciences (LIPI) Jl. Raya Bogor Km. 46 Cibinong Bogor Indonesia
| | - Gavin Irvine
- School of Chemistry and Chemical Engineering Queen's University Belfast Stranmillis Road, Belfast BT9 5AH UK
| | - Efrosyni Themistou
- School of Chemistry and Chemical Engineering Queen's University Belfast Stranmillis Road, Belfast BT9 5AH UK
| | - Biqiong Chen
- School of Mechanical and Aerospace Engineering Queen's University Belfast Stranmillis Road, Belfast BT9 5AH UK
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7
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Huxman C, Butler J. A Systematic Review of Compliant Mechanisms as Orthopedic Implants. J Med Device 2021. [DOI: 10.1115/1.4052011] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
Abstract
Currently available motion-preserving orthopedic implants offer many advantages but have several limitations to their use, including short device lifetime, high part count, loss of natural kinematics, and wear-induced osteolysis and implant loosening. Compliant mechanisms have been used to address some of these problems as they offer several potential advantages - namely, wear reduction, reduced part count, and the ability to achieve complex, patient-specific motion profiles. This article provides a systematic review of compliant mechanisms as orthopedic implants. Based on the PRISMA guidelines for an efficient review, this work identified fourteen implantable orthopedic devices that seek to restore anatomical motion by utilizing mechanical compliance. From reviewing these implants and their results, advantages and consequences for each are summarized. Trends were also identified in how these devices are capable of mitigating common challenges found in orthopedic design. Design considerations for the development of future compliant orthopedic implants are proposed and discussed.
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Affiliation(s)
- Connor Huxman
- School of Engineering Design, Technology, and Professional Programs, The Pennsylvania State University, 213 Hammond Building, University Park, PA 16802
| | - Jared Butler
- School of Engineering Design, Technology, and Professional Programs, The Pennsylvania State University, 213 Hammond Building, University Park, PA 16802
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8
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Sharma S, Mandhani A, Bose S, Basu B. Dynamically crosslinked polydimethylsiloxane-based polyurethanes with contact-killing antimicrobial properties as implantable alloplasts for urological reconstruction. Acta Biomater 2021; 129:122-137. [PMID: 33979672 DOI: 10.1016/j.actbio.2021.04.055] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2020] [Revised: 04/23/2021] [Accepted: 04/29/2021] [Indexed: 12/20/2022]
Abstract
A large population of patients is reported to suffer from urinary bladder-associated irreversible physiological disorders, rationalizing a continuous surge for structural and functional substitutes of urinary tissues, including ureters, bladder-wall, and urethra. The current gold standard for bladder reconstruction, an autologous gastrointestinal graft, is proven not to be an ideal substitute in the clinic. While addressing this unmet clinical need, a unique platform of antimicrobial polydimethyl siloxane-modified polyurethanes (TPU/PDMS) is designed and developed for its potential application as a urological implant. To the best of our knowledge, this study reports for the first time the successful integration of varying contents of PDMS within the molten polyurethane matrix using in situ crosslinking methodology. Thus, compatibilized binary blends possess clinically relevant viscoelastic properties to sustain high pressure, large distensions, and surgical manipulation. Furthermore, different chemical strategies are explored to covalently incorporate quaternized moieties, including 4-vinyl pyridine (4-VP), branched-polyethyleneimine (bPEI) as well as bPEI-grafted-(acrylic acid-co-vinylbenzyltriphenyl phosphonium chloride) (PAP), and counter urinary tract infections. The modified compositions, endowed with contact killing surfaces, reveal nearly three log reduction in bacterial growth in pathogenically infected artificial urine. Importantly, the antimicrobial TPU/PDMS blends support the uninhibited growth of mitochondrially viable murine fibroblasts, in a manner comparable to the medical-grade polyurethane. Collectively, the obtained results affirmed the newly developed polymers as promising biomaterials in reconstructive urology. STATEMENT OF SIGNIFICANCE: The clinical procedure for end-stage bladder disease remains replacement or augmentation of the bladder wall with a section of the patient's gastrointestinal tract. However, the absorptive and mucus-producing epithelium of intestinal segment is liable to short- and long-term complications. The dynamically crosslinked polydimethyl siloxane-based polyurethanes proposed herein, and the associated synthesis strategies to induce polycation grafted non-exhaustive contact-killing surfaces against uropathogents, have a significant clinical prospect in reconstructive urology. As an 'off-the-shelf' available alloplastic substitute, these blends offer the potential to circumvent the challenges associated with non-urinary autografts or scaffold based regenerative engineering and, thereby, shorten as well as simplify the surgical treatment. The targeted application has been conceived for a bladder patch to assist in various urinary diseases including, bladder carcinoma, refractory overactive bladder, interstitial cystitis, etc. However, given the ease of fabrication, moldability and the wide spectrum of mechanical properties that could be encompassed, these blends also present the possibility to be manifested into artificial ureteral or urethral conduits.
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Affiliation(s)
- Swati Sharma
- Materials Research Centre, Indian Institute of Science, Bangalore-560012, India
| | - Anil Mandhani
- Urology and Kidney Transplant Institute, Medanta-The Medicity, Gurgaon-12200, India
| | - Suryasarathi Bose
- Department of Materials Engineering, Indian Institute of Science, Bangalore-560012, India.
| | - Bikramjit Basu
- Materials Research Centre, Indian Institute of Science, Bangalore-560012, India; Center for Biosystems Science and Engineering, Indian Institute of Science, Bangalore-560012, India.
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9
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Zhang Q, Meyerhoff ME. Nitric Oxide Release for Enhanced Biocompatibility and Analytical Performance of Implantable Electrochemical Sensors. ELECTROANAL 2021. [DOI: 10.1002/elan.202100174] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Qi Zhang
- Department of Chemistry University of Michigan Ann Arbor MI 48109 USA
| | - Mark E. Meyerhoff
- Department of Chemistry University of Michigan Ann Arbor MI 48109 USA
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10
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Shao Z, Tao T, Xu H, Chen C, Lee I, Chung S, Dong Z, Li W, Ma L, Bai H, Chen Q. Recent progress in biomaterials for heart valve replacement: Structure, function, and biomimetic design. VIEW 2021. [DOI: 10.1002/viw.20200142] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Affiliation(s)
- Ziyu Shao
- Stomatology Hospital, School of Stomatology, Zhejiang University School of Medicine & Clinical Research Center for Oral Diseases of Zhejiang Province Key Laboratory of Oral Biomedical Research of Zhejiang Province, Cancer Center of Zhejiang University Hangzhou 310006 China
- State Key Laboratory of Chemical Engineering College of Chemical and Biological Engineering Zhejiang University Hangzhou China
| | - Tingting Tao
- Department of Cardiovascular Surgery The First Affiliated Hospital Zhejiang University School of Medicine Hangzhou Zhejiang Province China
| | - Hongfei Xu
- Department of Cardiovascular Surgery The First Affiliated Hospital Zhejiang University School of Medicine Hangzhou Zhejiang Province China
| | - Cen Chen
- College of Life Sciences and Medicine Zhejiang Sci‐Tech University Hangzhou China
| | - In‐Seop Lee
- College of Life Sciences and Medicine Zhejiang Sci‐Tech University Hangzhou China
- Institute of Natural Sciences Yonsei University Seoul Republic of Korea
| | - Sungmin Chung
- Biomaterials R&D Center GENOSS Co., Ltd. Suwon‐si Republic of Korea
| | - Zhihui Dong
- State Key Laboratory of Chemical Engineering College of Chemical and Biological Engineering Zhejiang University Hangzhou China
| | - Weidong Li
- Department of Cardiovascular Surgery The First Affiliated Hospital Zhejiang University School of Medicine Hangzhou Zhejiang Province China
| | - Liang Ma
- Department of Cardiovascular Surgery The First Affiliated Hospital Zhejiang University School of Medicine Hangzhou Zhejiang Province China
| | - Hao Bai
- Stomatology Hospital, School of Stomatology, Zhejiang University School of Medicine & Clinical Research Center for Oral Diseases of Zhejiang Province Key Laboratory of Oral Biomedical Research of Zhejiang Province, Cancer Center of Zhejiang University Hangzhou 310006 China
- State Key Laboratory of Chemical Engineering College of Chemical and Biological Engineering Zhejiang University Hangzhou China
| | - Qianming Chen
- Stomatology Hospital, School of Stomatology, Zhejiang University School of Medicine & Clinical Research Center for Oral Diseases of Zhejiang Province Key Laboratory of Oral Biomedical Research of Zhejiang Province, Cancer Center of Zhejiang University Hangzhou 310006 China
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Tang L, Long X, He X, Ding M, Zhao D, Luo F, Li J, Li Z, Tan H, Zhang H. Improved in vivo stability of silicon-containing polyurethane by fluorocarbon side chain modulation of the surface structure. J Mater Chem B 2021; 9:3210-3223. [PMID: 33885625 DOI: 10.1039/d1tb00140j] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
As a class of widely used biomedical materials, polyurethanes suffer from their insufficient stability in vivo. Although the commercialized silicone-polyetherurethanes (SiPEUs) have demonstrated excellent biostability compared with polyetherurethanes (PEUs) for long-term implantation, the usage of polydimethylsiloxane (PDMS) inevitably decreased the mechanical properties and unexpected breaches were observed. In this study, we introduced a fluorinated diol (FDO) into SiPEU to modulate the molecular interactions and micro-separated morphology. The fluorinated silicon-containing polyurethane (FSiPEU) was achieved with desirable silicone- and fluorine-enriched surfaces and mechanical properties at a low silicon content. As evidenced by in vitro culture of macrophages and in vivo hematoxylin-eosin (H&E) staining, FSiPEU demonstrated a minimized inflammatory response. After implantation in mice for 6 months, the material was devoid of significant surface degradation and had the least chain cleavage of soft segments. The results indicate that FSiPEU could be promising candidates for long-term implantation considering the combination of biostability, biocompatibility and mechanical performances.
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Affiliation(s)
- Lin Tang
- College of Polymer Science and Engineering, State Key Laboratory of Polymer Materials Engineering, Sichuan University, Chengdu 610065, China.
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Influence of Hard Segment Content and Diisocyanate Structure on the Transparency and Mechanical Properties of Poly(dimethylsiloxane)-Based Urea Elastomers for Biomedical Applications. Polymers (Basel) 2021; 13:polym13020212. [PMID: 33435271 PMCID: PMC7827567 DOI: 10.3390/polym13020212] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2020] [Revised: 01/01/2021] [Accepted: 01/04/2021] [Indexed: 11/26/2022] Open
Abstract
The effect of hard segment content and diisocyanate structure on the transparency and mechanical properties of soft poly(dimethylsiloxane) (PDMS)-based urea elastomers (PSUs) was investigated. A series of PSU elastomers were synthesized from an aminopropyl-terminated PDMS (M¯n: 16,300 g·mol−1), which was prepared by ring chain equilibration of the monomers octamethylcyclotetrasiloxane (D4) and 1,3-bis(3-aminopropyl)-tetramethyldisiloxane (APTMDS). The hard segments (HSs) comprised diisocyanates of different symmetry, i.e., 4,4′-methylenebis(cyclohexyl isocyanate) (H12MDI), 4,4′-methylenebis(phenyl isocyanate) (MDI), isophorone diisocyanate (IPDI), and trans-1,4-cyclohexane diisocyanate (CHDI). The HS contents of the PSU elastomers based on H12MDI and IPDI were systematically varied between 5% and 20% by increasing the ratio of the diisocyanate and the chain extender APTMDS. PSU copolymers of very low urea HS contents (1.0–1.6%) were prepared without the chain extender. All PSU elastomers and copolymers exhibited good elastomeric properties and displayed elongation at break values between 600% and 1100%. The PSUs with HS contents below 10% were transparent and became increasingly translucent at HS contents of 15% and higher. The Young’s modulus (YM) and ultimate tensile strength values of the elastomers increased linearly with increasing HS content. The YM values differed significantly among the PSU copolymers depending on the symmetry of the diisocyanate. The softest elastomer was that based on the asymmetric IPDI. The elastomers synthesized from H12MDI and MDI both exhibited an intermediate YM, while the stiffest elastomer, i.e., that comprising the symmetric CHDI, had a YM three-times higher than that prepared with IPDI. The PSUs were subjected to load–unload cycles at 100% and 300% strain to study the influence of HS morphology on 10-cycle hysteresis behavior. At 100% strain, the first-cycle hysteresis values of the IPDI- and H12MDI-based elastomers first decreased to a minimum of approximately 9–10% at an HS content of 10% and increased again to 22–28% at an HS content of 20%. A similar, though less pronounced, trend was observed at 300% strain. First-cycle hysteresis among the PSU copolymers at 100% strain was lowest in the case of CHDI and highest in the IPDI-based elastomer. However, this effect was reversed at 300% strain, with CHDI displaying the highest hysteresis in the first cycle. In vitro cytotoxicity tests performed using HaCaT cells did not show any adverse effects, revealing their potential suitability for biomedical applications.
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13
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Slippery Liquid-Infused Porous Polymeric Surfaces Based on Natural Oil with Antimicrobial Effect. Polymers (Basel) 2021; 13:polym13020206. [PMID: 33430082 PMCID: PMC7826890 DOI: 10.3390/polym13020206] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2020] [Revised: 12/11/2020] [Accepted: 01/05/2021] [Indexed: 01/31/2023] Open
Abstract
Many polymer materials have found a wide variety of applications in biomedical industries due to their excellent mechanical properties. However, the infections associated with the biofilm formation represent serious problems resulting from the initial bacterial attachment on the polymeric surface. The development of novel slippery liquid-infused porous surfaces (SLIPSs) represents promising method for the biofilm formation prevention. These surfaces are characterized by specific microstructural roughness able to hold lubricants inside. The lubricants create a slippery layer for the repellence of various liquids, such as water and blood. In this study, effective antimicrobial modifications of polyethylene (PE) and polyurethane (PU), as commonly used medical polymers, were investigated. For this purpose, low-temperature plasma treatment was used initially for activation of the polymeric surface, thereby enhancing surface and adhesion properties. Subsequently, preparation of porous microstructures was achieved by electrospinning technique using polydimethylsiloxane (PDMS) in combination with polyamide (PA). Finally, natural black seed oil (BSO) infiltrated the produced fiber mats acting as a lubricating layer. The optimized fiber mats' production was achieved using PDMS/PA mixture at ratio 1:1:20 (g/g/mL) using isopropyl alcohol as solvent. The surface properties of produced slippery surfaces were analyzed by various microscopic and optics techniques to obtain information about wettability, sliding behavior and surface morphology/topography. The modified PE and PU substrates demonstrated slippery behavior of an impinged water droplet at a small tilting angle. Moreover, the antimicrobial effects of the produced SLIPs using black seed oil were proven against Gram-positive Staphylococcus aureus (S. aureus) and Gram-negative Escherichia coli (E. coli).
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Jenney C, Millson P, Grainger DW, Grubbs R, Gunatillake P, McCarthy SJ, Runt J, Beith J. Assessment of a Siloxane Poly(urethane‐urea) Elastomer Designed for Implantable Heart Valve Leaflets. ADVANCED NANOBIOMED RESEARCH 2020. [DOI: 10.1002/anbr.202000032] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Affiliation(s)
- Chris Jenney
- Research and Product Development Foldax, Inc. Salt Lake City UT 84103 USA
| | - Peter Millson
- Research and Product Development Foldax, Inc. Salt Lake City UT 84103 USA
| | - David W. Grainger
- Department of Biomedical Engineering Department of Pharmaceutics and Pharmaceutical Chemistry University of Utah Salt Lake City UT 84112 USA
| | - Robert Grubbs
- Division of Chemistry and Chemical Engineering California Institute of Technology Pasadena CA 91125 USA
| | - Pathiraja Gunatillake
- Commonwealth Scientific and Industrial Research Organization Manufacturing Clayton VIC 3168 Australia
| | | | - James Runt
- Department of Materials Science and Engineering Penn State University University Park PA 16802 USA
| | - Jason Beith
- Research and Product Development Foldax, Inc. Salt Lake City UT 84103 USA
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15
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Liang Y, Kim S, Yang E, Choi H. Omni-Directional Protected Nanofiber Membranes by Surface Segregation of PDMS-Terminated Triblock Copolymer for High-Efficiency Oil/Water Emulsion Separation. ACS APPLIED MATERIALS & INTERFACES 2020; 12:25324-25333. [PMID: 32379960 DOI: 10.1021/acsami.0c05559] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
An excellent antifouling membrane with high permeate flux is required for oil/water emulsion separation due to ever-increasing oily industrial wastewater. Thus, an intriguing integration of the Omni-directional protected porous membrane that combines a high porosity nanofiber membrane with a surface segregation mechanism is established for the first time. By applying polydimethylsiloxane(PDMS)-terminated triblock copolymer, the enrichment of the hydrophilic poly(ethylene oxide) (PEO) segment and the nonpolar PDMS segment on the surface of the nanofiber endowed the nanofiber membrane with underwater oleophobicity and low oil adhesion force, exhibiting oil resistance as well as oil release property. An ultrahigh permeate flux of ∼7115 L m-2 h-1 with a separation efficiency of ∼97.88% is achieved under the driving force of gravity (∼0.9 kPa), which is the highest permeate flux ever reported under similar conditions. Moreover, the surface segregation nanofiber membrane shows excellent reusability and ultrahigh permeate flux with the assistance of stirring in a long-term test, revealing the promising performances for the further particular application of oily wastewater.
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Affiliation(s)
- Yejin Liang
- School of Earth Science and Environmental Engineering, Gwangju Institute of Science and Technology (GIST), 123 Cheomdangwagi-ro, Buk-gu, Gwangju, 61005, South Korea
| | - Soyoung Kim
- School of Earth Science and Environmental Engineering, Gwangju Institute of Science and Technology (GIST), 123 Cheomdangwagi-ro, Buk-gu, Gwangju, 61005, South Korea
| | - Eunmok Yang
- School of Earth Science and Environmental Engineering, Gwangju Institute of Science and Technology (GIST), 123 Cheomdangwagi-ro, Buk-gu, Gwangju, 61005, South Korea
| | - Heechul Choi
- School of Earth Science and Environmental Engineering, Gwangju Institute of Science and Technology (GIST), 123 Cheomdangwagi-ro, Buk-gu, Gwangju, 61005, South Korea
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16
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Li Y, Yuan L, Ming H, Li X, Tang L, Zhang J, Wang R, Wang G, Jiang Y, Li Z, Luo F, Li J, Tan H, Fu Q. Enhanced Hydrolytic Resistance of Fluorinated Silicon-Containing Polyether Urethanes. Biomacromolecules 2020; 21:1460-1470. [DOI: 10.1021/acs.biomac.9b01768] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- Yaomin Li
- College of Polymer Science and Engineering, State Key Laboratory of Polymer Materials Engineering, Sichuan University, Chengdu 610065, China
| | - Lei Yuan
- College of Polymer Science and Engineering, State Key Laboratory of Polymer Materials Engineering, Sichuan University, Chengdu 610065, China
| | - Hao Ming
- College of Polymer Science and Engineering, State Key Laboratory of Polymer Materials Engineering, Sichuan University, Chengdu 610065, China
| | - Xin Li
- College of Polymer Science and Engineering, State Key Laboratory of Polymer Materials Engineering, Sichuan University, Chengdu 610065, China
| | - Lin Tang
- College of Polymer Science and Engineering, State Key Laboratory of Polymer Materials Engineering, Sichuan University, Chengdu 610065, China
| | - Jian Zhang
- College of Polymer Science and Engineering, State Key Laboratory of Polymer Materials Engineering, Sichuan University, Chengdu 610065, China
| | - Ruichen Wang
- College of Polymer Science and Engineering, State Key Laboratory of Polymer Materials Engineering, Sichuan University, Chengdu 610065, China
| | - Gang Wang
- Sichuan Institute for Food and Drug Control, Chengdu, China
| | - Yan Jiang
- Sichuan Institute for Food and Drug Control, Chengdu, China
| | - Zhen Li
- College of Polymer Science and Engineering, State Key Laboratory of Polymer Materials Engineering, Sichuan University, Chengdu 610065, China
| | - Feng Luo
- College of Polymer Science and Engineering, State Key Laboratory of Polymer Materials Engineering, Sichuan University, Chengdu 610065, China
| | - Jiehua Li
- College of Polymer Science and Engineering, State Key Laboratory of Polymer Materials Engineering, Sichuan University, Chengdu 610065, China
| | - Hong Tan
- College of Polymer Science and Engineering, State Key Laboratory of Polymer Materials Engineering, Sichuan University, Chengdu 610065, China
| | - Qiang Fu
- College of Polymer Science and Engineering, State Key Laboratory of Polymer Materials Engineering, Sichuan University, Chengdu 610065, China
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17
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Roy S, Bhalani DV, Jewrajka SK. Surface segregation of segmented amphiphilic copolymer of poly(dimethylsiloxane) and poly(ethylene glycol) on poly(vinylidene fluoride) blend membrane for oil–water emulsion separation. Sep Purif Technol 2020. [DOI: 10.1016/j.seppur.2019.115940] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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18
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Koh LB, Zuo K, Kumar GP, Ding X, Leo HL, Cui F, Charles CJ, Yang YY, Yim EKF, Ho P. Optimization of a Novel Preferential Covered Stent through Bench Experiments and in Vitro Platelet Activation Studies. ACS Biomater Sci Eng 2019; 5:6216-6230. [PMID: 33405529 DOI: 10.1021/acsbiomaterials.9b00763] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Bare metal stenting (BMS) does not adequately address the atheroembolic characteristic of carotid artery stenosis. While simple covered stents (CS) may prevent dislodged fragments of the atherosclerotic plaque from entering the blood stream, they also block blood flow into the major branches of the artery alongside the lesion, which is not desirable. Preferential covered stents (PCS) behave as a covered stent in a tubular part of a vessel but maintain side-branch flow over the bifurcation region by means of slits in the membrane. Stent design, membrane material, and slits configuration are the three main components contributing to stent performance. Optimization of PCS designs was conducted and tested. METHODS A newly designed BMS was developed and compared to a commercially available peripheral stent. Two materials (expanded poly(tetrafluoroethylene)) and silicone polyurethane co-polymers (Elast-eon E2A) were used as stent coverings with slits applied using various cutting methods to form the PCS. These PCS samples were tested for physical resilience, flexibility, ability to preserve side-branch flow, slit edge roughness, and platelet activation. RESULTS Fabrication of E2A-coated stents required pretreatment of the stent with poly(ethylene glycol) to achieve firm attachment. The newly designed BMS with nine crowns design and larger cell size showed higher flexibility than commercially available stents. A combination of a larger stent cell size, E2A membrane coating, and three slits per stent cell unit configuration resulted in preserved side-branch flow similar to physiological conditions in the flow experiment. Slit edge roughness changed with different cutting methods and laser machine cutting parameters. In vitro studies showed platelet activation was minimal with lower slit edge roughness samples. CONCLUSION An optimized PCS prototype was developed consisting of a newly designed stent, E2A membrane, and a three-slit pattern created by specific femtosecond laser cutting.
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Affiliation(s)
| | | | | | | | | | | | | | | | - Evelyn K F Yim
- Department of Chemical Engineering, University of Waterloo, Ontario, Canada
| | - Pei Ho
- Department of Cardiac, Thoracic & Vascular Surgery, National University Health System, Singapore
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19
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El-Kurdi M, Soletti L, McGrath J, Linhares S, Rousselle S, Greisler H, Edelman E, Schoen FJ. Functional remodeling of an electrospun polydimethylsiloxane-based polyether urethane external vein graft support device in an ovine model. J Biomed Mater Res A 2019; 107:2135-2149. [PMID: 31094084 PMCID: PMC6689261 DOI: 10.1002/jbm.a.36724] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2018] [Revised: 02/13/2019] [Accepted: 05/07/2019] [Indexed: 11/07/2022]
Abstract
Saphenous vein graft (SVG) failure rates are unacceptably high, and external mechanical support may improve patency. We studied the histologic remodeling of a conformal, electrospun, polydimethylsiloxane-based polyether urethane external support device for SVGs and evaluated graft structural evolution in adult sheep to 2 years. All sheep (N = 19) survived to their intended timepoints, and angiography showed device-treated SVG geometric stability over time (30, 90, 180, 365, or 730 days), with an aggregated graft patency rate of 92%. There was minimal inflammation associated with the device material at all timepoints. By 180 days, treated SVG remodeling was characterized by minimal/nonprogressive intimal hyperplasia; polymer fragmentation and integration; as well as the development of a neointima, and a confluent endothelium. By 1-year, the graft developed a media-like layer by remodeling the neointima, and elastic fibers formed well-defined structures that subtended the neo-medial layer of the remodeled SVG. Immunohistochemistry showed that this neo-media was populated with smooth muscle cells, and the intima was lined with endothelial cells. These data suggest that treated SVGs were structurally remodeled by 180 days, and developed arterial-like features by 1 year, which continued to mature to 2 years. Device-treated SVGs remodeled into arterial-like conduits with stable long-term performance as arterial grafts in adult sheep.
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Affiliation(s)
| | | | | | | | | | - Howard Greisler
- Loyola University, Maywood, IL and Hines VA Hospital, Hines, IL
| | - Elazer Edelman
- Massachusetts Institute of Technology, Cambridge, MA, Harvard Medical School, Boston, MA, Brigham and Women’s Hospital, Boston, MA
| | - Frederick J. Schoen
- Brigham and Women’s Hospital, Boston, MA, and Harvard Medical School, Boston, MA
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20
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Dandeniyage LS, Knower W, Adhikari R, Bown M, Shanks R, Adhikari B, Gunatillake PA. In vitro oxidative stability of high strength siloxane poly(urethane-urea) elastomers based on linked-macrodiol. J Biomed Mater Res B Appl Biomater 2019; 107:2557-2565. [PMID: 30835945 DOI: 10.1002/jbm.b.34346] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2018] [Revised: 02/05/2019] [Accepted: 02/10/2019] [Indexed: 01/23/2023]
Abstract
In vitro oxidative stability of two siloxane poly(urethane urea)s synthesized using 4,4'-methylenediphenyl diisocyanate (in SiPUU-1) and Isophorone diisocyanate (in SiPUU-2) linked soft segment was evaluated using 20% H2 O2 and 0.1 mol/L CoCl2 solution at 37°C under 150% strain. Commercially available siloxane polyurethane (Elast-Eon™ 2A) and polyether polyurethane (ChronoThane P™ 80A) were used as negative and positive controls, respectively. ChronoSil™ 80A was included as another commercially available polycarbonate polyurethane. Scanning electron microscopic (SEM) examinations, attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy, and molecular weight reduction revealed the extensive degradation of ChronoThane P™ 80A after 90 days while SiPUU-1, SiPUU-2 and Elast-Eon™ 2A showed no noticeable surface degradation. ChronoSil™ 80A showed degradation in both soft and hard segments. Tensile testing was carried out only on unstrained polyurethanes for 90 days. ChronoThane P™ 80A showed 35% loss in ultimate tensile strength and it was only 13-14% for SiPUU-1 and Elast-Eon™ 2A. However, the tensile strength of ChronoSil™ 80A was not significantly affected. The results of this study proved that SiPUU-1 possess oxidative stability comparable with Elast-Eon™ 2A. © 2019 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 107B:2557-2565, 2019.
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Affiliation(s)
- Loshini S Dandeniyage
- School of Science, RMIT University, Melbourne, Victoria, 3000, Australia.,CSIRO Manufacturing, Clayton, Victoria, 3168, Australia
| | - Warren Knower
- CSIRO Manufacturing, Clayton, Victoria, 3168, Australia
| | - Raju Adhikari
- CSIRO Manufacturing, Clayton, Victoria, 3168, Australia
| | - Mark Bown
- CSIRO Manufacturing, Clayton, Victoria, 3168, Australia
| | - Robert Shanks
- School of Science, RMIT University, Melbourne, Victoria, 3000, Australia
| | - Benu Adhikari
- School of Science, RMIT University, Melbourne, Victoria, 3000, Australia
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21
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Xie F, Zhang T, Bryant P, Kurusingal V, Colwell JM, Laycock B. Degradation and stabilization of polyurethane elastomers. Prog Polym Sci 2019. [DOI: 10.1016/j.progpolymsci.2018.12.003] [Citation(s) in RCA: 143] [Impact Index Per Article: 28.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
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22
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Lin M, Firoozi N, Tsai CT, Wallace MB, Kang Y. 3D-printed flexible polymer stents for potential applications in inoperable esophageal malignancies. Acta Biomater 2019; 83:119-129. [PMID: 30366130 DOI: 10.1016/j.actbio.2018.10.035] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2018] [Revised: 10/09/2018] [Accepted: 10/22/2018] [Indexed: 01/19/2023]
Abstract
Palliation therapy for dysphagia using esophageal stents is the current treatment of choice for those patients with inoperable esophageal malignancies. However, the metallic and plastic stents currently used in the clinical setting may cause complications, such as tumor ingrowth and stent migration into the stomach. To effectively reduce/overcome these complications, we designed a tubular, flexible polymer stent with spirals. The parameters of the spirals were computationally optimized by using a finite element analysis. The designed polymer stents with optimized spirals were then printed by a 3D printing technique. 3D-printed tubular polymer stents without spirals served as controls. The self-expansion and anti-migration properties of the printed stent were characterized in an ex vivo normal porcine esophagus. The biodegradability test of the stent was performed in a neutral buffer and acidic gastric buffer. The cytotoxicity of the new stent was examined through the viability test of human esophagus epithelial cells. Results showed the self-expansion force of the 3D-printed polymer stent with spirals was higher than the stent without spirals. The anti-migration force of the 3D-printed stent with spirals was significantly higher than that of the stent without spirals. Furthermore, the stent with spirals significantly decreased the migration distance compared to the non-spiral 3D-printed polymer stent. Degradation study showed that the polymer materials started to degrade after six weeks and the compressive strength of the stent was not significantly decreased with time. In vitro cell viability results further indicated that the polymer stent does not have any cytotoxicity. Together, these results showed that the 3D-printed stent with spirals has potential applications in the treatment of inoperable esophageal malignancies. STATEMENT OF SIGNIFICANCE: In this study, we developed a new 3D-printed flexible tubular polymeric stent with spirals. The mechanical properties of the 3D-printed polymer stent are modulated by changing the ratios of PLA to TPU. The stent is flexible enough to be compressed in a clinically available stent delivery system, and can self-expand after it is released. The self-expansion force of the stent with spirals is higher than that of non-spiral stents. The spirals on the outside of the stent significantly increased the anti-migration force compared to non-spiral stents in an ex vivo normal pig esophagus. Together, the 3D-printed stent with spirals will bring promising potential in the treatment of inoperable esophagus malignancies or benign strictures.
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Affiliation(s)
- Maohua Lin
- Department of Ocean and Mechanical Engineering, College of Engineering and Computer Science, Florida Atlantic University, Boca Raton, FL 33431, USA
| | - Negar Firoozi
- Department of Ocean and Mechanical Engineering, College of Engineering and Computer Science, Florida Atlantic University, Boca Raton, FL 33431, USA
| | - Chi-Tay Tsai
- Department of Ocean and Mechanical Engineering, College of Engineering and Computer Science, Florida Atlantic University, Boca Raton, FL 33431, USA
| | - Michael B Wallace
- Department of Gastroenterology and Hepatology, Mayo Clinic, Jacksonville, FL 32224, USA
| | - Yunqing Kang
- Department of Ocean and Mechanical Engineering, College of Engineering and Computer Science, Florida Atlantic University, Boca Raton, FL 33431, USA; Department of Biomedical Science, Charles E. Schmidt College of Medicine, Florida Atlantic University, Boca Raton, FL 33431, USA.
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23
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Mehrali M, Bagherifard S, Akbari M, Thakur A, Mirani B, Mehrali M, Hasany M, Orive G, Das P, Emneus J, Andresen TL, Dolatshahi‐Pirouz A. Blending Electronics with the Human Body: A Pathway toward a Cybernetic Future. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2018; 5:1700931. [PMID: 30356969 PMCID: PMC6193179 DOI: 10.1002/advs.201700931] [Citation(s) in RCA: 46] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/27/2017] [Revised: 05/24/2018] [Indexed: 05/22/2023]
Abstract
At the crossroads of chemistry, electronics, mechanical engineering, polymer science, biology, tissue engineering, computer science, and materials science, electrical devices are currently being engineered that blend directly within organs and tissues. These sophisticated devices are mediators, recorders, and stimulators of electricity with the capacity to monitor important electrophysiological events, replace disabled body parts, or even stimulate tissues to overcome their current limitations. They are therefore capable of leading humanity forward into the age of cyborgs, a time in which human biology can be hacked at will to yield beings with abilities beyond their natural capabilities. The resulting advances have been made possible by the emergence of conformal and soft electronic materials that can readily integrate with the curvilinear, dynamic, delicate, and flexible human body. This article discusses the recent rapid pace of development in the field of cybernetics with special emphasis on the important role that flexible and electrically active materials have played therein.
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Affiliation(s)
- Mehdi Mehrali
- Technical University of DenmarkDTU NanotechCenter for Nanomedicine and Theranostics2800KgsDenmark
| | - Sara Bagherifard
- Department of Mechanical EngineeringPolitecnico di Milano20156MilanItaly
| | - Mohsen Akbari
- Laboratory for Innovations in MicroEngineering (LiME)Department of Mechanical EngineeringUniversity of VictoriaVictoriaBCV8P 5C2Canada
- Center for Biomedical ResearchUniversity of VictoriaVictoriaV8P 5C2Canada
- Center for Advanced Materials and Related Technologies (CAMTEC)University of VictoriaVictoriaV8P 5C2Canada
| | - Ashish Thakur
- Technical University of DenmarkDTU NanotechCenter for Nanomedicine and Theranostics2800KgsDenmark
| | - Bahram Mirani
- Laboratory for Innovations in MicroEngineering (LiME)Department of Mechanical EngineeringUniversity of VictoriaVictoriaBCV8P 5C2Canada
- Center for Biomedical ResearchUniversity of VictoriaVictoriaV8P 5C2Canada
- Center for Advanced Materials and Related Technologies (CAMTEC)University of VictoriaVictoriaV8P 5C2Canada
| | - Mohammad Mehrali
- Process and Energy DepartmentDelft University of TechnologyLeeghwaterstraat 392628CBDelftThe Netherlands
| | - Masoud Hasany
- Technical University of DenmarkDTU NanotechCenter for Nanomedicine and Theranostics2800KgsDenmark
| | - Gorka Orive
- NanoBioCel GroupLaboratory of PharmaceuticsSchool of PharmacyUniversity of the Basque Country UPV/EHUPaseo de la Universidad 701006Vitoria‐GasteizSpain
- Biomedical Research Networking Centre in Bioengineering, Biomaterials, and Nanomedicine (CIBER‐BBN)Vitoria‐Gasteiz28029Spain
- University Institute for Regenerative Medicine and Oral Implantology—UIRMI (UPV/EHU‐Fundación Eduardo Anitua)Vitoria01007Spain
| | - Paramita Das
- School of Chemical and Biomedical EngineeringNanyang Technological University62 Nanyang DriveSingapore637459Singapore
| | - Jenny Emneus
- Technical University of DenmarkDTU Nanotech2800KgsDenmark
| | - Thomas L. Andresen
- Technical University of DenmarkDTU NanotechCenter for Nanomedicine and Theranostics2800KgsDenmark
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Gunatillake PA, Dandeniyage LS, Adhikari R, Bown M, Shanks R, Adhikari B. Advancements in the Development of Biostable Polyurethanes. POLYM REV 2018. [DOI: 10.1080/15583724.2018.1493694] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Affiliation(s)
| | - Loshini S. Dandeniyage
- CSIRO Manufacturing, Clayton, Victoria, Australia
- School of Sciences, RMIT University, Melbourne, Victoria, Australia
| | | | - Mark Bown
- CSIRO Manufacturing, Clayton, Victoria, Australia
| | - Robert Shanks
- School of Sciences, RMIT University, Melbourne, Victoria, Australia
| | - Benu Adhikari
- CSIRO Manufacturing, Clayton, Victoria, Australia
- School of Sciences, RMIT University, Melbourne, Victoria, Australia
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25
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Marcano A, Fatyeyeva K, Koun M, Dubuis P, Grimme M, Marais S. Recent developments in the field of barrier and permeability properties of segmented polyurethane elastomers. REV CHEM ENG 2018. [DOI: 10.1515/revce-2017-0033] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Abstract
Polyurethane (PU) elastomers represent an important class of segmented copolymers. Thanks to many available chemical compositions, a rather broad range of chemical, physical, and biocompatible properties of PU can be obtained. These polymers are often characterized by high tensile and tear strength, elongation, fatigue life, and wear resistance. However, their relatively high permeability towards gases and water as well as their biocompatibility still limits the PU’s practical application, especially for biomedical use, for example, in implants and medical devices. In this review, the barrier and permeability properties of segmented PUs related to their chemical structure and physical and chemical properties have been discussed, including the latest developments and different approaches to improve the PU barrier properties.
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Affiliation(s)
- Aracelys Marcano
- Normandie University, UNIROUEN, INSA ROUEN, CNRS, PBS , 76000 Rouen , France
- CARMAT SA, 36 Avenue de l’Europe, Immeuble l’Etendard , 78140 Vélizy Villacoublay , France
| | - Kateryna Fatyeyeva
- Normandie University, UNIROUEN, INSA ROUEN, CNRS, PBS , 76000 Rouen , France
| | - Malys Koun
- ALTEN, 221bis Bd. Jean Jaurès , 92100 Boulogne-Billancourt , France
| | - Pascal Dubuis
- INOPROD, 46 Rue de Sarlieve , 63800 Cournon D’Auvergne , France
| | - Marc Grimme
- CARMAT SA, 36 Avenue de l’Europe, Immeuble l’Etendard , 78140 Vélizy Villacoublay , France
| | - Stéphane Marais
- Normandie University, UNIROUEN, INSA ROUEN, CNRS, PBS , 76000 Rouen , France
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26
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Li Z, Yang J, Ye H, Ding M, Luo F, Li J, Li J, Tan H, Fu Q. Simultaneous Improvement of Oxidative and Hydrolytic Resistance of Polycarbonate Urethanes Based on Polydimethylsiloxane/Poly(hexamethylene carbonate) Mixed Macrodiols. Biomacromolecules 2018; 19:2137-2145. [PMID: 29669212 DOI: 10.1021/acs.biomac.8b00234] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
The degradation behaviors including oxidation and hydrolysis of silicone modified polycarbonate urethanes were thoroughly investigated. These polyurethanes were based on polyhexamethylene carbonate (PHMC)/polydimethylsiloxane (PDMS) mixed macrodiols with molar ratio of PDMS ranging from 5% to 30%. It was proved that PDMS tended to migrate toward surface and even a small amount of PDMS could form a silicone-like surface. Macrophages-mediated oxidation process indicated that the PDMS surface layer was desirable to protect the fragile soft PHMC from the attack of degradative species. Hydrolysis process was probed in detail after immersing in boiling buffered water using combined analytical tools. Hydrolytically stable PDMS could act as protective shields for the bulk to hinder the chain scission of polycarbonate carbonyls whereas the hydrolysis of urethane linkages was less affected. Although the promoted phase separation at higher PDMS fractions lead to possible physical defects and mechanical compromise after degradation, simultaneously enhanced oxidation and hydrolysis resistance could be achieved for the polyurethanes with proper PDMS incorporation.
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Affiliation(s)
- Zhen Li
- College of Polymer Science and Engineering, State Key Laboratory of Polymer Materials Engineering , Sichuan University , Chengdu 610065 , China
| | - Jian Yang
- College of Polymer Science and Engineering, State Key Laboratory of Polymer Materials Engineering , Sichuan University , Chengdu 610065 , China
| | - Heng Ye
- College of Polymer Science and Engineering, State Key Laboratory of Polymer Materials Engineering , Sichuan University , Chengdu 610065 , China
| | - Mingming Ding
- College of Polymer Science and Engineering, State Key Laboratory of Polymer Materials Engineering , Sichuan University , Chengdu 610065 , China
| | - Feng Luo
- College of Polymer Science and Engineering, State Key Laboratory of Polymer Materials Engineering , Sichuan University , Chengdu 610065 , China
| | - Jianshu Li
- College of Polymer Science and Engineering, State Key Laboratory of Polymer Materials Engineering , Sichuan University , Chengdu 610065 , China
| | - Jiehua Li
- College of Polymer Science and Engineering, State Key Laboratory of Polymer Materials Engineering , Sichuan University , Chengdu 610065 , China
| | - Hong Tan
- College of Polymer Science and Engineering, State Key Laboratory of Polymer Materials Engineering , Sichuan University , Chengdu 610065 , China
| | - Qiang Fu
- College of Polymer Science and Engineering, State Key Laboratory of Polymer Materials Engineering , Sichuan University , Chengdu 610065 , China
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27
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Wheatley D, Bernacca G, Tolland M, O'connor B, Fisher J, Williams D. Hydrodynamic Function of a Biostable Polyurethane Flexible Heart Valve after Six Months in Sheep. Int J Artif Organs 2018. [DOI: 10.1177/039139880102400207] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Survival to six months for sheep with a non-biostable polyurethane mitral heart valve prosthesis has been reported previously, however, with surface degradation and accumulation of calcified fibrin/thrombus that impaired leaflet motion and compromised hydrodynamic function. Newly available biostable polyurethanes may overcome this problem. Six adult sheep with biostable polyurethane trileaflet heart valve prostheses of documented hydrodynamic performance, implanted in the mitral position, were allowed to survive for 6 months. Explanted valves were photographed, resubmitted to hydrodynamic function testing, and studied by light and electron microscopy. Explanted valves were structurally intact and differed little in appearance from their preimplant state. Hydrodynamic testing showed no deterioration in pressure gradient or energy losses compared with pre-implant values. Biostable polyurethanes demonstrated improved blood compatibility leaving leaflets flexible and valve function unimpaired. Biostable polyurethanes may thus improve prospects for prolonged function of synthetic heart valve prostheses.
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Affiliation(s)
- D.J. Wheatley
- Department of Cardiac Surgery, University of Glasgow, Glasgow - UK
| | - G.M. Bernacca
- Department of Cardiac Surgery, University of Glasgow, Glasgow - UK
| | - M.M. Tolland
- Department of Cardiac Surgery, University of Glasgow, Glasgow - UK
| | - B. O'connor
- Department of Cardiac Surgery, University of Glasgow, Glasgow - UK
| | - J. Fisher
- The School of Mechanical Engineering, University of Leeds, Leeds - UK
| | - D.F. Williams
- Department of Clinical Engineering, University of Liverpool, Liverpool - UK
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Cutiongco MFA, Chua BMX, Neo DJH, Rizwan M, Yim EKF. Functional differences between healthy and diabetic endothelial cells on topographical cues. Biomaterials 2018; 153:70-84. [PMID: 29125983 PMCID: PMC5724387 DOI: 10.1016/j.biomaterials.2017.10.037] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2017] [Revised: 10/04/2017] [Accepted: 10/20/2017] [Indexed: 12/23/2022]
Abstract
The endothelial lining of blood vessels is severely affected in type II diabetes. Yet, there is still a paucity on the use of diabetic endothelial cells for study and assessment of implantable devices targeting vascular disease. This critically impairs our ability to determine appropriate topographical cues to be included in implantable devices that can be used to maintain or improve endothelial cell function in vivo. Here, the functional responses of healthy and diabetic human coronary arterial endothelial cells were studied and observed to differ depending on topography. Gratings (2 μm) maintained normal endothelial functions such as adhesiveness, angiogenic capacity and cell-cell junction formation, and reduced immunogenicity of healthy cells. However, a significant and consistent effect was not observed in diabetic cells. Instead, diabetic endothelial cells cultured on the perpendicularly aligned multi-scale hierarchical gratings (250 nm gratings on 2 μm gratings) drastically reduced the uptake of oxidized low-density lipoprotein, decreased immune activation, and accelerated cell migration. Concave microlens (1.8 μm diameter) topography was additionally observed to overwhelmingly deteriorate diabetic endothelial cell function. The results of this study support a new paradigm and approach in the design and testing of implantable devices and biomedical interventions for diabetic patients.
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Affiliation(s)
- Marie F A Cutiongco
- Mechanobiology Institute, National University of Singapore, T-Lab, #10-01, 5A Engineering Drive 1, Singapore, 117411; Department of Biomedical Engineering, Block E4 #04-08, 4 Engineering Drive 3, National University of Singapore, 117583, Singapore
| | - Bryan M X Chua
- Department of Biomedical Engineering, Block E4 #04-08, 4 Engineering Drive 3, National University of Singapore, 117583, Singapore
| | - Dawn J H Neo
- Mechanobiology Institute, National University of Singapore, T-Lab, #10-01, 5A Engineering Drive 1, Singapore, 117411
| | - Muhammad Rizwan
- Department of Chemical Engineering, University of Waterloo, 200 University Avenue West, Waterloo, Ontario, Canada, N2L 3G1
| | - Evelyn K F Yim
- Mechanobiology Institute, National University of Singapore, T-Lab, #10-01, 5A Engineering Drive 1, Singapore, 117411; Department of Biomedical Engineering, Block E4 #04-08, 4 Engineering Drive 3, National University of Singapore, 117583, Singapore; Department of Surgery, National University of Singapore, Singapore; Department of Chemical Engineering, University of Waterloo, 200 University Avenue West, Waterloo, Ontario, Canada, N2L 3G1.
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29
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Dandeniyage LS, Gunatillake PA, Adhikari R, Bown M, Shanks R, Adhikari B. Development of high strength siloxane poly(urethane-urea) elastomers based on linked macrodiols for heart valve application. J Biomed Mater Res B Appl Biomater 2017; 106:1712-1720. [PMID: 28858405 DOI: 10.1002/jbm.b.33970] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2017] [Revised: 07/25/2017] [Accepted: 07/29/2017] [Indexed: 11/11/2022]
Abstract
Mixed macrodiol based siloxane poly(urethane-urea)s (SiPUU) having number average molecular weights in the range 87-129 kDa/mol were synthesized to give elastomers with high tensile and tear strengths required to fabricate artificial heart valves. Polar functional groups were introduced into the soft segment to improve the poor segmental compatibility of siloxane polyurethanes. This was achieved by linking α,ω-bis(6-hydroxyethoxypropyl) poly(dimethylsiloxane) (PDMS) or poly(hexamethylene oxide) (PHMO) macrodiols with either 4,4'-methylenediphenyl diisocyanate (MDI), hexamethylene diisocyanate (HDI) or isophorone diisocyanate (IPDI) prior to polyurethane synthesis. The hard segment was composed of MDI, and a 1:1 mixture of 1,3-bis(4-hydroxybutyl)-1,1,3,3-tetramethyldisiloxane and 1,2-ethylene diamine. We report the effect of urethane linkers in soft segments on properties of the SiPUU. PHMO linked with either MDI or IPDI produced SiPUU with the highest tensile and tear strengths. Linking PDMS hardly affected the tensile strength; however, the tear strength was improved. The stress-strain curves showed no plastic deformation region typically observed for conventional polyurethanes indicating good creep resistance. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 106B: 1712-1720, 2018.
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Affiliation(s)
- Loshini S Dandeniyage
- School of Science, RMIT University, Melbourne, Victoria 3000, Australia.,CSIRO Manufacturing, Clayton, Victoria 3168, Australia
| | | | - Raju Adhikari
- CSIRO Manufacturing, Clayton, Victoria 3168, Australia
| | - Mark Bown
- CSIRO Manufacturing, Clayton, Victoria 3168, Australia
| | - Robert Shanks
- School of Science, RMIT University, Melbourne, Victoria 3000, Australia
| | - Benu Adhikari
- School of Science, RMIT University, Melbourne, Victoria 3000, Australia.,CSIRO Manufacturing, Clayton, Victoria 3168, Australia
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30
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Andriani Y, Chua JMW, Chua BYJ, Phang IY, Shyh-Chang N, Tan WS. Polyurethane acrylates as effective substrates for sustained in vitro culture of human myotubes. Acta Biomater 2017; 57:115-126. [PMID: 28435079 DOI: 10.1016/j.actbio.2017.04.022] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2016] [Revised: 04/14/2017] [Accepted: 04/19/2017] [Indexed: 12/23/2022]
Abstract
Muscular disease has debilitating effects with severe damage leading to death. Our knowledge of muscle biology, disease and treatment is largely derived from non-human cell models, even though non-human cells are known to differ from human cells in their biochemical responses. Attempts to develop highly sought after in vitro human cell models have been plagued by early cell delamination and difficulties in achieving human myotube culture in vitro. In this work, we developed polyurethane acrylate (PUA) materials to support long-term in vitro culture of human skeletal muscle tissue. Using a constant base with modulated crosslink density we were able to vary the material modulus while keeping surface chemistry and roughness constant. While previous studies have focused on materials that mimic soft muscle tissue with stiffness ca. 12kPa, we investigated materials with tendon-like surface moduli in the higher 150MPa to 2.4GPa range, which has remained unexplored. We found that PUA of an optimal modulus within this range can support human myoblast proliferation, terminal differentiation and sustenance beyond 35days, without use of any extracellular protein coating. Results show that PUA materials can serve as effective substrates for successful development of human skeletal muscle cell models and are suitable for long-term in vitro studies. STATEMENT OF SIGNIFICANCE We developed polyurethane acrylates (PUA) to modulate the human skeletal muscle cell growth and maturation in vitro by controlling surface chemistry, morphology and tuning material's stiffness. PUA was able to maintain muscle cell viability for over a month without any detectable signs of material degradation. The best performing PUA prevented premature cell detachment from the substrate which often hampered long-term muscle cell studies. It also supported muscle cell maturation up to the late stages of differentiation. The significance of these findings lies in the possibility to advance studies on muscle cell biology, disease and therapy by using human muscle cells instead of relying on the widely used animal-based in vitro models.
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31
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Rozeik MM, Wheatley DJ, Gourlay T. Investigating the Suitability of Carbon Nanotube Reinforced Polymer in Transcatheter Valve Applications. Cardiovasc Eng Technol 2017. [PMID: 28623503 PMCID: PMC5573758 DOI: 10.1007/s13239-017-0313-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
The current delivery size of transcatheter aortic valves, limited by the thickness of their pericardial leaflets, correlates with a high prevalence of major vascular complications. Polyurethane valves can be developed to a fraction of the thickness of pericardial valves through the addition of carbon nanotubes to reinforce their leaflets. This study investigates the suitability of a novel carbon nanotube reinforced leaflet to reduce the delivery profile of transcatheter aortic valves. Carbon nanotube polyurethane composites were developed with thicknesses of 50 μm and their mechanical properties were determined in relation to various environmental effects. The composites demonstrated improvements to the material stiffness, particularly at increasing strain rates compared to the neat polymer. However, increasing nanotube concentrations significantly decreased the fatigue life of the composites. Key findings highlighted a potential for carbon nanotube reinforcement in valve replacement which experience very high strain rates during the cardiac cycle. Further testing is needed to achieve a strong nanotube-matrix interface which will prolong the cyclic fatigue life and further strengthen tensile properties. Testing on the durability and haemocompatibility of these composite heart valves are ongoing.
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Affiliation(s)
- Monica M Rozeik
- Department of Biomedical Engineering, Wolfson Centre, University of Strathclyde, 106 Rottenrow, Glasgow, G4 0NW, UK.
| | - David J Wheatley
- Department of Biomedical Engineering, Wolfson Centre, University of Strathclyde, 106 Rottenrow, Glasgow, G4 0NW, UK
| | - Terence Gourlay
- Department of Biomedical Engineering, Wolfson Centre, University of Strathclyde, 106 Rottenrow, Glasgow, G4 0NW, UK
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32
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Stynes GD, Gengenbach TR, Kiroff GK, Morrison WA, Kirkland MA. Thiol surface functionalization via continuous phase plasma polymerization of allyl mercaptan, with subsequent maleimide-linked conjugation of collagen. J Biomed Mater Res A 2017; 105:1940-1948. [DOI: 10.1002/jbm.a.36064] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2016] [Revised: 02/23/2017] [Accepted: 03/07/2017] [Indexed: 11/08/2022]
Affiliation(s)
- Gil D. Stynes
- Department of Surgery; St Vincent's Hospital, University of Melbourne; Victoria Australia
- Barwon Biomedical Research, University Hospital Geelong; Victoria Australia
- Commonwealth Scientific and Industrial Research Organisation (CSIRO); Victoria Australia
- Institute for Frontier Materials, Deakin University; Victoria Australia
| | - Thomas R. Gengenbach
- Commonwealth Scientific and Industrial Research Organisation (CSIRO); Victoria Australia
| | - George K. Kiroff
- Queen Elizabeth Hospital, The University of Adelaide; South Australia Australia
| | - Wayne A. Morrison
- Department of Surgery; St Vincent's Hospital, University of Melbourne; Victoria Australia
| | - Mark A. Kirkland
- Institute for Frontier Materials, Deakin University; Victoria Australia
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33
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Zhu R, Wang X, Yang J, Wang Y, Zhang Z, Hou Y, Lin F. Influence of hydroxyl-terminated polydimethylsiloxane on high-strength biocompatible polycarbonate urethane films. ACTA ACUST UNITED AC 2016; 12:015011. [PMID: 27934785 DOI: 10.1088/1748-605x/12/1/015011] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
The present study describes a series of novel polycarbonate urethane films that were fabricated via the solution-casting method from 4,4'-methylenebis(cyclohexyl isocyanate) (H12MDI) and 1,4-butanediol (BDO) chain extender as hard segments, poly(1,6-hexanediol)carbonate diols (PCDL) and hydroxyl-terminated polydimethylsiloxane (PDMS) as soft segments, with dibutyltin dilaurate as the catalyst. Varied molar ratios of PDMS (less than 30%) were utilized to enhance the mechanical properties and biocompatibilities. The microstructure and degrees of phase separation were characterized using atomic force microscopy. The chemical structure and surface morphology of the materials were further confirmed by attenuated total reflectance Fourier transform infrared spectroscopy, 1H NMR and 13C NMR, water droplet contact angle and scanning electron microscopy. Thermal properties were measured by differential scanning calorimetry. MTT assay and hemolytic tests were studied for evaluating cellular viability and hemocompatibility of fabricated films using L929 fibroblast cells and adult rabbit blood. The results demonstrated polyurethane films with soft segments partially replaced by PDMS could remarkably improve the biocompatibility while maintaining relatively stable mechanical behavior, making them exciting potential candidates for artificial vessels or other tissue engineering applications.
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Affiliation(s)
- Rong Zhu
- State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan 430070, People's Republic of China. Biomedical Materials and Engineering Research Center of Hubei Province, Wuhan University of Technology, Wuhan 430070, People's Republic of China
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34
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Mahomed A, Hukins DWL, Kukureka SN. Effect of accelerated aging on the viscoelastic properties of a medical grade silicone. Biomed Mater Eng 2016; 25:415-23. [PMID: 26407203 DOI: 10.3233/bme-151538] [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] [Indexed: 11/15/2022]
Abstract
The viscoelastic properties of cylinders (diameter 5 mm, height 2.2 ± 0.2 mm) of Nagor silicone elastomer of medium hardness, were investigated before and after the specimens had undergone accelerated aging in saline solution at 70°C for 38, 76 and 114 days (to simulate aging at 37°C, for 1, 2 and 3 years, respectively). All sets of specimens were immersed in physiological saline solution at 37°C during testing and the properties were measured using dynamic mechanical analysis (DMA). A sinusoidal cyclic compression of 40 N ± 5 N was applied over a frequency range, f, of 0.02-25 Hz. Values of the storage, E', and loss, E″, moduli were found to depend on f; the dependence of E' or E″ on the logarithm (base 10) of f was represented by a second-order polynomial. After accelerated aging, the E' and E″ values did not increase significantly (p<0.05). Furthermore, scanning electron microscopy (SEM) showed that accelerated aging did not affect the surface morphology of silicone. Attenuated total reflectance Fourier transform infra-red spectroscopy (ATR-FTIR) showed that accelerated aging had a negligible effect on the surface chemical structures of the material. Differential scanning calorimetry (DSC) showed no changes to the bulk properties of silicone, following accelerated aging.
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Affiliation(s)
- Aziza Mahomed
- School of Mechanical Engineering, University of Birmingham, Birmingham, UK.,School of Metallurgy and Materials, University of Birmingham, Birmingham, UK
| | - David W L Hukins
- School of Mechanical Engineering, University of Birmingham, Birmingham, UK
| | - Stephen N Kukureka
- School of Metallurgy and Materials, University of Birmingham, Birmingham, UK
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35
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Zhu R, Wang Y, Zhang Z, Ma D, Wang X. Synthesis of polycarbonate urethane elastomers and effects of the chemical structures on their thermal, mechanical and biocompatibility properties. Heliyon 2016; 2:e00125. [PMID: 27441296 PMCID: PMC4946310 DOI: 10.1016/j.heliyon.2016.e00125] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2016] [Revised: 04/25/2016] [Accepted: 06/14/2016] [Indexed: 12/05/2022] Open
Abstract
In this study, to obtain biomedical polyurethane elastomers with good mechanical properties and biocompatibility, a series of polycarbonate urethanes were synthesized via a two-step solution of polymerization method using the poly(1,6-hexanediol)carbonate diols (PCDL) as the soft segment, 4,4′-methylenebis(cyclohexyl isocyanate) (H12MDI), 1,6-hexamethylene diisocyanate (HDI) and 1,4-butanediol (BDO) as the hard segment with dibutyltin dilaurate as the catalyst. In this article, we illustrated the physical behaviors were obviously influenced by synthetic routes. And their chemical and physical structures were investigated by gel permeation chromatograph (GPC), differential scanning calorimeter (DSC), fourier transform infrared spectrography (FT-IR) and mechanical properties tests. The surface wettability were studied by contact angle measurement (CA). As a kind of short-term implant biomaterial, the results of the hemolysis and platelet adhesive tests were recorded by spectrophotometer and scanning electron microscopy (SEM), indicating the materials have a great potential for developments and applications in biomedical field.
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Affiliation(s)
- Rong Zhu
- State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan 430070, China; Biomedical Materials and Engineering Research Center of Hubei Province, Wuhan University of Technology, Wuhan 430070, China
| | - Yiyu Wang
- State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan 430070, China; Biomedical Materials and Engineering Research Center of Hubei Province, Wuhan University of Technology, Wuhan 430070, China
| | - Zongrui Zhang
- State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan 430070, China; Biomedical Materials and Engineering Research Center of Hubei Province, Wuhan University of Technology, Wuhan 430070, China
| | - Daiwei Ma
- State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan 430070, China; Biomedical Materials and Engineering Research Center of Hubei Province, Wuhan University of Technology, Wuhan 430070, China
| | - Xinyu Wang
- State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan 430070, China; Biomedical Materials and Engineering Research Center of Hubei Province, Wuhan University of Technology, Wuhan 430070, China
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36
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Stefanović IS, Špírková M, Poręba R, Steinhart M, Ostojić S, Tešević V, Pergal MV. Study of the Properties of Urethane–Siloxane Copolymers Based on Poly(propylene oxide)-b-poly(dimethylsiloxane)-b-poly(propylene oxide) Soft Segments. Ind Eng Chem Res 2016. [DOI: 10.1021/acs.iecr.5b04975] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Ivan S. Stefanović
- Institute
of Chemistry, Technology and Metallurgy (ICTM)—Center of Chemistry, University of Belgrade, Studentski Trg 12-16, 11000 Belgrade, Serbia
| | - Milena Špírková
- Institute of Macromolecular Chemistry AS CR, v.v.i. (IMC), Heyrovsky Sq. 2, 16206 Prague 6, Czech Republic
| | - Rafał Poręba
- Institute of Macromolecular Chemistry AS CR, v.v.i. (IMC), Heyrovsky Sq. 2, 16206 Prague 6, Czech Republic
| | - Miloš Steinhart
- Institute of Macromolecular Chemistry AS CR, v.v.i. (IMC), Heyrovsky Sq. 2, 16206 Prague 6, Czech Republic
| | - Sanja Ostojić
- Institute
of General and Physical Chemistry, University of Belgrade, Studentski
Trg 12-16, 11000 Belgrade, Serbia
| | - Vele Tešević
- Faculty
of Chemistry, University of Belgrade, Studentski Trg 12-16, 11000 Belgrade, Serbia
| | - Marija V. Pergal
- Institute
of Chemistry, Technology and Metallurgy (ICTM)—Center of Chemistry, University of Belgrade, Studentski Trg 12-16, 11000 Belgrade, Serbia
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37
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Chandel AKS, Kumar CU, Jewrajka SK. Effect of Polyethylene Glycol on Properties and Drug Encapsulation-Release Performance of Biodegradable/Cytocompatible Agarose-Polyethylene Glycol-Polycaprolactone Amphiphilic Co-Network Gels. ACS APPLIED MATERIALS & INTERFACES 2016; 8:3182-92. [PMID: 26760672 DOI: 10.1021/acsami.5b10675] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
We synthesized agarose-polycaprolactone (Agr-PCL) bicomponent and Agr-polyethylene glycol-PCL (Agr-PEG-PCL) tricomponent amphiphilic co-network (APCN) gels by the sequential nucleophilic substitution reaction between amine-functionalized Agr and activated halide terminated PCL or PCL-b-PEG-b-PCL copolymer for the sustained and localized delivery of hydrophilic and hydrophobic drugs. The biodegradability of the APCNs was confirmed using lipase and by hydrolytic degradation. These APCN gels displayed good cytocompatibility and blood compatibility. Importantly, these APCN gels exhibited remarkably high drug loading capacity coupled with sustained and triggered release of both hydrophilic and hydrophobic drugs. PEG in the APCNs lowered the degree of phase separation and enhanced the mechanical property of the APCN gels. The drug loading capacity and the release kinetics were also strongly influenced by the presence of PEG, the nature of release medium, and the nature of the drug. Particularly, PEG in the APCN gels significantly enhanced the 5-fluorouracil loading capacity and lowered its release rate and burst release. Release kinetics of highly water-soluble gemcitabine hydrochloride and hydrophobic prednisolone acetate depended on the extent of water swelling of the APCN gels. Cytocompatibility/blood compatibility and pH and enzyme-triggered degradation together with sustained release of drugs show great promise for the use of these APCN gels in localized drug delivery and tissue engineering applications.
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Affiliation(s)
- Arvind K Singh Chandel
- Reverse Osmosis Membrane Division, CSIR and ‡Academy of Scientific and Innovative Research-AcSIR, Central Salt and Marine Chemicals Research Institute , Gijubhai Badheka Marg, Bhavnagar, Gujarat 364002, India
| | - Chinta Uday Kumar
- Reverse Osmosis Membrane Division, CSIR and ‡Academy of Scientific and Innovative Research-AcSIR, Central Salt and Marine Chemicals Research Institute , Gijubhai Badheka Marg, Bhavnagar, Gujarat 364002, India
| | - Suresh K Jewrajka
- Reverse Osmosis Membrane Division, CSIR and ‡Academy of Scientific and Innovative Research-AcSIR, Central Salt and Marine Chemicals Research Institute , Gijubhai Badheka Marg, Bhavnagar, Gujarat 364002, India
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38
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Zhao J, Xu R, Luo G, Wu J, Xia H. Self-healing poly(siloxane-urethane) elastomers with remoldability, shape memory and biocompatibility. Polym Chem 2016. [DOI: 10.1039/c6py01499b] [Citation(s) in RCA: 83] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The poly(siloxane-urethane) elastomers with microphase separation structure and Diels–Alder bonds show high healing efficiency, good mechanical property and good biocompatibility.
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Affiliation(s)
- Jian Zhao
- State Key Laboratory of Polymer Materials Engineering
- Polymer Research Institute
- Sichuan University
- Chengdu
- China
| | - Rui Xu
- China State Key Laboratory of Trauma
- Burn and Combined Injury
- Institute of Burn Research
- Southwest Hospital
- Third Military Medical University
| | - Gaoxing Luo
- China State Key Laboratory of Trauma
- Burn and Combined Injury
- Institute of Burn Research
- Southwest Hospital
- Third Military Medical University
| | - Jun Wu
- China State Key Laboratory of Trauma
- Burn and Combined Injury
- Institute of Burn Research
- Southwest Hospital
- Third Military Medical University
| | - Hesheng Xia
- State Key Laboratory of Polymer Materials Engineering
- Polymer Research Institute
- Sichuan University
- Chengdu
- China
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39
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Mishra A, Seethamraju K, Delaney J, Willoughby P, Faust R. Long-term in vitro hydrolytic stability of thermoplastic polyurethanes. J Biomed Mater Res A 2015; 103:3798-806. [PMID: 26097127 DOI: 10.1002/jbm.a.35523] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2015] [Revised: 06/05/2015] [Accepted: 06/08/2015] [Indexed: 11/07/2022]
Abstract
Long-term in vitro stability of thermoplastic polyurethanes (TPUs) was studied for up to 52 weeks in phosphate buffer solution at 37, 55, and 80°C. Water uptake, molecular weights, and tensile properties were measured at regular intervals of 4, 8, 16, 32, and 52 weeks. The rate of molecular weight reduction increased with increasing temperature, and after 52 weeks at 80°C, all commercial polycarbonate (Bionate-55D, Quadrathane-80A, and Chronoflex-80A), poly(dimethylsiloxane) (ElastEon-2A) and polyether (Elasthane-55D) TPUs showed significant (43-51%) molecular weight (Mn ) reduction. The polyisobutylene (PIB)-based TPU exhibited a significantly lower decrease in Mn (26%) after 52 weeks at 80°C. For Bionate-55D and ElastEon-2A, at 80°C in dry nitrogen atmosphere substantial thermal degradation was observed, while for the other TPUs the effect of thermal degradation is small. The temperature dependent reduction of molecular weight was interpreted by simple second order kinetics. From the approximately linear Arrhenius plots the activation energies were calculated, which were highest for PIB-PU-020 and lowest for ElastEon-2A. For Elasthane-55D the in vitro molecular weight reduction was compared with that of explanted leads. The molecular weight reduction in vivo was much smaller than that predicted from in vitro data, which may suggest that the in vitro model does not adequately describe the hydrolysis in vivo. In the absence of validation for the other TPUs that in vitro methods closely reproduce in vivo degradation, it is unknown how these results correlate with in vivo performance.
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Affiliation(s)
- Abhinay Mishra
- Department of Chemistry, Polymer Science Program, University of Massachusetts Lowell, Lowell, Massachusetts, 01854
| | - Kasyap Seethamraju
- Boston Scientific Corporation, 4100 Hamline Ave. North, St. Paul, Minnesota, 55112
| | - Joseph Delaney
- Boston Scientific Corporation, 4100 Hamline Ave. North, St. Paul, Minnesota, 55112
| | - Patrick Willoughby
- Boston Scientific Corporation, 4100 Hamline Ave. North, St. Paul, Minnesota, 55112
| | - Rudolf Faust
- Department of Chemistry, Polymer Science Program, University of Massachusetts Lowell, Lowell, Massachusetts, 01854
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40
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Wilkoff BL, Rickard J, Tkatchouk E, Padsalgikar AD, Gallagher G, Runt J. The biostability of cardiac lead insulation materials as assessed from long-term human implants. J Biomed Mater Res B Appl Biomater 2015; 104:411-21. [DOI: 10.1002/jbm.b.33405] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2014] [Revised: 12/16/2014] [Accepted: 02/26/2015] [Indexed: 11/11/2022]
Affiliation(s)
- Bruce L. Wilkoff
- Cleveland Clinic, Department of Cardiovascular Medicine; Cleveland Ohio
| | - John Rickard
- Department of Cardiology; Johns Hopkins University; Baltimore Maryland
| | - Ekaterina Tkatchouk
- Implantable Electronic Systems Division; St. Jude Medical; Sylmar California
| | | | - Genevieve Gallagher
- Implantable Electronic Systems Division; St. Jude Medical; St. Paul Minnesota
| | - James Runt
- Department of Materials Science and Engineering; Penn State University, University Park; Pennsylvania
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41
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Kaur G, Adhikari R, Cass P, Bown M, Evans MDM, Vashi AV, Gunatillake P. Graphene/polyurethane composites: fabrication and evaluation of electrical conductivity, mechanical properties and cell viability. RSC Adv 2015. [DOI: 10.1039/c5ra20214k] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Conductive composites of graphene and a siloxane polyurethane (Elast-Eon™) were prepared to explore their potential for use in biomedical applications.
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42
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Nitric oxide release from polydimethylsiloxane-based polyurethanes. J Appl Biomater Funct Mater 2014; 12:172-82. [PMID: 24744231 PMCID: PMC6161757 DOI: 10.5301/jabfm.5000192] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/06/2013] [Indexed: 11/26/2022] Open
Abstract
Localized nitric oxide (NO) release from polymeric materials holds much promise for the prevention of coagulation often associated with implantable and extracorporeal blood-contacting devices. Films of polyurethane (PU) containing incorporated polyethyleneimine were thus exposed to NO gas to form diazeniumdiolates (NONOates) in situ. Donor incorporation and NO gas exposure did not affect the mechanical properties of the films. The NO release capacity increased with increasing polydimethylsiloxane (PDMS) content in the soft segment of the PU: total capacity could be more than doubled (P<0.05) from 0.093 ± 0.028 to 0.225 ± 0.004 mmol/g when the PDMS content was increased from 0 to 100%. Release kinetics were best approximated using a modified Korsemeyer-Peppas power law (R2=0.95-0.99). Despite the resultant rapid initial decrease in NO release rates, values above that observed for quiescent endothelial cells (0.83 pmol·cm−2·s−1) were maintained for extended periods of 5-10 days, while rates above that of a stimulated endothelium (2.7-6.8 pmol·cm−2·s−1) were achieved for the first 24 hours. This method of NONOate formation may be advantageous, as potential premature NO release by exposure of diazeniumdiolated donors during incorporation, processing and storage, can be avoided by in situ diazoniumdiolation closer to the time of implantation.
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Zhang Y, Fan H, Li BG. Synthesis and characterization of advance PA6- b-PDMS multiblock copolymers. J Appl Polym Sci 2014. [DOI: 10.1002/app.41114] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Yanyan Zhang
- State Key Laboratory of Chemical Engineering, Department of Chemical and Biological Engineering; Zhejiang University; Hangzhou 310027 China
| | - Hong Fan
- State Key Laboratory of Chemical Engineering, Department of Chemical and Biological Engineering; Zhejiang University; Hangzhou 310027 China
| | - Bo-Geng Li
- State Key Laboratory of Chemical Engineering, Department of Chemical and Biological Engineering; Zhejiang University; Hangzhou 310027 China
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Stefanović IS, Djonlagić J, Tovilović G, Nestorov J, Antić VV, Ostojić S, Pergal MV. Poly(urethane-dimethylsiloxane) copolymers displaying a range of soft segment contents, noncytotoxic chemistry, and nonadherent properties toward endothelial cells. J Biomed Mater Res A 2014; 103:1459-75. [PMID: 25046378 DOI: 10.1002/jbm.a.35285] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2014] [Revised: 07/07/2014] [Accepted: 07/18/2014] [Indexed: 11/09/2022]
Abstract
Polyurethane copolymers based on α,ω-dihydroxypropyl poly(dimethylsiloxane) (PDMS) with a range of soft segment contents were prepared by two-stage polymerization, and their microstructures, thermal, thermomechanical, and surface properties, as well as in vitro hemo- and cytocompatibility were evaluated. All utilized characterization methods confirmed the existence of moderately microphase separated structures with the appearance of some microphase mixing between segments as the PDMS (i.e., soft segment) content increased. Copolymers showed higher crystallinity, storage moduli, surface roughness, and surface free energy, but less hydrophobicity with decreasing PDMS content. Biocompatibility of copolymers was evaluated using an endothelial EA.hy926 cell line by direct contact, an extraction method and after pretreatment of copolymers with multicomponent protein mixture, as well as by a competitive protein adsorption assay. Copolymers showed no toxic effect to endothelial cells and all copolymers, except that with the lowest PDMS content, exhibited resistance to endothelial cell adhesion, suggesting their unsuitability for long-term biomedical devices which particularly require re-endothelialization. All copolymers exhibited excellent resistance to fibrinogen adsorption and adsorbed more albumin than fibrinogen in the competitive adsorption assay, suggesting their good hemocompatibility. The noncytotoxic chemistry of these synthesized materials, combined with their nonadherent properties which are inhospitable to cell attachment and growth, underlie the need for further investigations to clarify their potential for use in short-term biomedical devices.
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Affiliation(s)
- Ivan S Stefanović
- Institute of Chemistry, Technology and Metallurgy, University of Belgrade, Njegoševa 12, 11000, Belgrade, Serbia
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Qidwai M, Sheraz MA, Ahmed S, Alkhuraif AA, ur Rehman I. Preparation and characterization of bioactive composites and fibers for dental applications. Dent Mater 2014; 30:e253-63. [PMID: 24954646 DOI: 10.1016/j.dental.2014.05.022] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2013] [Revised: 03/18/2014] [Accepted: 05/21/2014] [Indexed: 10/25/2022]
Abstract
OBJECTIVES The present study was carried out to create composites and fibers using polyurethane (PU) with hydroxyapatite (HA) that could be used for dental applications. METHODS Composites with varying HA concentration were prepared by solution casting technique. Similarly, PU-HA fibers with varying PU hard and soft segments and fixed HA concentration were also prepared. Various characterization techniques, such as, X-ray diffractometry, differential scanning calorimetry, scanning electron microscopy and Fourier transform infrared spectroscopy in conjunction with photo-acoustic sampling cell were employed to study the composites and fibers for changes in their physicochemical properties before and after immersion in artificial saliva at 37°C for up to 5 days. RESULTS The results indicated formation of amorphous apatite layers with maximum amorphicity in composites containing highest amount of HA with 5 days of immersion in artificial saliva. Similarly, fibers with more PU hard segment resulted in better transformation of crystalline HA to its amorphous state with increasing immersion time thus confirming the bioactive nature of the HA-PU fibers. SIGNIFICANCE Concentrations of HA and PU hard segment along with the duration of immersion in artificial saliva are two major factors involved in the modification of solid-state properties of HA. The amorphous apatite layer on the surface is known to have tendency to bind with living tissues and hence the use of optimum amount of HA and PU hard segment in composites and fibers, respectively could help in the development of novel dental filling material.
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Affiliation(s)
- Maryam Qidwai
- Department of Materials Science and Engineering, The Kroto Research Institute, University of Sheffield, North Campus, Broad Lane, Sheffield S3 7HQ, UK
| | - Muhammad Ali Sheraz
- Department of Materials Science and Engineering, The Kroto Research Institute, University of Sheffield, North Campus, Broad Lane, Sheffield S3 7HQ, UK
| | - Sofia Ahmed
- Department of Materials Science and Engineering, The Kroto Research Institute, University of Sheffield, North Campus, Broad Lane, Sheffield S3 7HQ, UK
| | | | - Ihtesham ur Rehman
- Department of Materials Science and Engineering, The Kroto Research Institute, University of Sheffield, North Campus, Broad Lane, Sheffield S3 7HQ, UK.
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Effect of atom transfer radical polymerization macroinitiator on properties of poly(meth)acrylate-based pentablock type of thermoplastic elastomers. POLYMER 2014. [DOI: 10.1016/j.polymer.2014.03.019] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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Rozeik MM, Wheatley DJ, Gourlay T. The aortic valve: structure, complications and implications for transcatheter aortic valve replacement. Perfusion 2014; 29:285-300. [DOI: 10.1177/0267659114521650] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The aortic valve operates in a complex haemodynamic environment, opening and closing over 100,000 times a day. When complications arise, such as aortic stenosis, prognosis can be very poor, leading to death within the first few years. Surgical valve replacement is currently the standard treatment for aortic stenosis. A thorough understanding of the anatomy and function of the native valve is imperative when developing a prosthetic replacement that can withstand the complex demands of the heart. This review focuses on the anatomy, structure and disease of the aortic valve and the implications for a transcatheter aortic valve replacement (TAVR). Current complications with TAVR, such as major vascular bleeding, conduction disturbances and patient-prosthesis mismatch (PPM), can be overcome by reducing the delivery profile and through the use of more accurate imaging technologies to work towards a fully functional and durable prosthesis.
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Affiliation(s)
- MM Rozeik
- Department of Biomedical Engineering, University of Strathclyde, Glasgow, UK
| | - DJ Wheatley
- Department of Biomedical Engineering, University of Strathclyde, Glasgow, UK
| | - T Gourlay
- Department of Biomedical Engineering, University of Strathclyde, Glasgow, UK
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Zhao X, Su Y, Li Y, Zhang R, Zhao J, Jiang Z. Engineering amphiphilic membrane surfaces based on PEO and PDMS segments for improved antifouling performances. J Memb Sci 2014. [DOI: 10.1016/j.memsci.2013.08.044] [Citation(s) in RCA: 121] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
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Pergal MV, Nestorov J, Tovilović G, Ostojić S, Gođevac D, Vasiljević-Radović D, Djonlagić J. Structure and properties of thermoplastic polyurethanes based on poly(dimethylsiloxane): Assessment of biocompatibility. J Biomed Mater Res A 2013; 102:3951-64. [DOI: 10.1002/jbm.a.35071] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2013] [Revised: 11/29/2013] [Accepted: 12/18/2013] [Indexed: 11/08/2022]
Affiliation(s)
- Marija V. Pergal
- Institute of Chemistry; Technology and Metallurgy, University of Belgrade; Njegoševa 12 Belgrade 11000 Serbia
| | - Jelena Nestorov
- Department of Biochemistry; Institute for Biological Research “Siniša Stanković”; University of Belgrade; 142 Despot Stefan Blvd Belgrade 11000 Serbia
| | - Gordana Tovilović
- Department of Biochemistry; Institute for Biological Research “Siniša Stanković”; University of Belgrade; 142 Despot Stefan Blvd Belgrade 11000 Serbia
| | - Sanja Ostojić
- Institute of General and Physical Chemistry; University of Belgrade; Studentski trg 12-16 Belgrade 11000 Serbia
| | - Dejan Gođevac
- Institute of Chemistry; Technology and Metallurgy, University of Belgrade; Njegoševa 12 Belgrade 11000 Serbia
| | - Dana Vasiljević-Radović
- Institute of Chemistry; Technology and Metallurgy, University of Belgrade; Njegoševa 12 Belgrade 11000 Serbia
| | - Jasna Djonlagić
- Faculty of Technology and Metallurgy; University of Belgrade; Karnegijeva 4 Belgrade 11000 Serbia
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