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Strasser P, Teasdale I. Main-Chain Phosphorus-Containing Polymers for Therapeutic Applications. Molecules 2020; 25:E1716. [PMID: 32276516 PMCID: PMC7181247 DOI: 10.3390/molecules25071716] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2020] [Revised: 04/02/2020] [Accepted: 04/04/2020] [Indexed: 02/07/2023] Open
Abstract
Polymers in which phosphorus is an integral part of the main chain, including polyphosphazenes and polyphosphoesters, have been widely investigated in recent years for their potential in a number of therapeutic applications. Phosphorus, as the central feature of these polymers, endears the chemical functionalization, and in some cases (bio)degradability, to facilitate their use in such therapeutic formulations. Recent advances in the synthetic polymer chemistry have allowed for controlled synthesis methods in order to prepare the complex macromolecular structures required, alongside the control and reproducibility desired for such medical applications. While the main polymer families described herein, polyphosphazenes and polyphosphoesters and their analogues, as well as phosphorus-based dendrimers, have hitherto predominantly been investigated in isolation from one another, this review aims to highlight and bring together some of this research. In doing so, the focus is placed on the essential, and often mutual, design features and structure-property relationships that allow the preparation of such functional materials. The first part of the review details the relevant features of phosphorus-containing polymers in respect to their use in therapeutic applications, while the second part highlights some recent and innovative applications, offering insights into the most state-of-the-art research on phosphorus-based polymers in a therapeutic context.
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Affiliation(s)
- Paul Strasser
- Institute of Polymer Chemistry, Johannes Kepler University Linz (JKU), Altenberger Straße 69, A-4040 Linz, Austria
| | - Ian Teasdale
- Institute of Polymer Chemistry, Johannes Kepler University Linz (JKU), Altenberger Straße 69, A-4040 Linz, Austria
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2
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Ogueri KS, Allcock HR, Laurencin CT. Generational Biodegradable and Regenerative Polyphosphazene Polymers and their Blends with Poly (lactic-co-glycolic acid). Prog Polym Sci 2019; 98:101146. [PMID: 31551636 PMCID: PMC6758934 DOI: 10.1016/j.progpolymsci.2019.101146] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
New fields such as regenerative engineering have driven the design of advanced biomaterials with a wide range of properties. Regenerative engineering is a multidisciplinary approach that integrates the fields of advanced materials science and engineering, stem cell science, physics, developmental biology, and clinical translation for the regeneration of complex tissues. The complexity and demands of this innovative approach have motivated the synthesis of new polymeric materials that can be customized to meet application-specific needs. Polyphosphazene polymers represent this fundamental change and are gaining renewed interest as biomaterials due to their outstanding synthetic flexibility, neutral bioactivity (buffering degradation products), and tunable properties across the range. Polyphosphazenes are a unique class of polymers composed of an inorganic backbone with alternating phosphorus and nitrogen atoms. Each phosphorus atom bears two substituents, with a wide variety of side groups available for property optimization. Polyphosphazenes have been investigated as potential biomaterials for regenerative engineering. Polyphosphazenes for use in regenerative applications have evolved as a class to include different generations of degradable polymers. The first generation of polyphosphazenes for tissue regeneration entailed the use of hydrolytically active side groups such as imidazole, lactate, glycolate, glucosyl, or glyceryl groups. These side groups were selected based on their ability to sensitize the polymer backbone to hydrolysis, which allowed them to break down into non-toxic small molecules that could be metabolized or excreted. The second generation of degradable polyphosphazenes developed consisted of polymers with amino acid ester side groups. When blended with poly (lactic acid-co-glycolic acid) (PLGA), the feasibility of neutralizing acidic degradation products of PLGA was demonstrated. The blends formed were mostly partially miscible. The desire to improve miscibility led to the design of the third generation of degradable polyphosphazenes by incorporating dipeptide side groups which impart significant hydrogen bonding capability to the polymer for the formation of completely miscible polyphosphazene-PLGA blends. Blend system of the dipeptide-based polyphosphazene and PLGA exhibit a unique degradation behavior that allows the formation of interconnected porous structures upon degradation. These inherent pore-forming properties have distinguished degradable polyphosphazenes as a potentially important class of biomaterials for further study. The design considerations and strategies for the different generations of degradable polyphosphazenes and future directions are discussed.
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Affiliation(s)
- Kenneth S. Ogueri
- Department of Materials Science and Engineering, University of Connecticut, Storrs, CT 06269, USA
- Connecticut Convergence Institute for Translation in Regenerative Engineering, University of Connecticut Health Center, Farmington, CT 06030, USA
| | - Harry R. Allcock
- Department of Chemistry, The Pennsylvania State University, University Park, PA 16802, USA
- Department of Materials Science and Engineering, The Pennsylvania State University, University Park, PA 16802, USA
| | - Cato T. Laurencin
- Department of Materials Science and Engineering, University of Connecticut, Storrs, CT 06269, USA
- Connecticut Convergence Institute for Translation in Regenerative Engineering, University of Connecticut Health Center, Farmington, CT 06030, USA
- Department of Orthopaedic Surgery, University of Connecticut Health Center, Farmington, CT 06030, USA
- Department of Biomedical Engineering, University of Connecticut, Storrs, CT 06269, USA
- Department of Chemical and Biomolecular Engineering, University of Connecticut, Storrs, CT 06269, USA
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Ogueri KS, Jafari T, Escobar Ivirico JL, Laurencin CT. POLYMERIC BIOMATERIALS FOR SCAFFOLD-BASED BONE REGENERATIVE ENGINEERING. REGENERATIVE ENGINEERING AND TRANSLATIONAL MEDICINE 2019; 5:128-154. [PMID: 31423461 PMCID: PMC6697158 DOI: 10.1007/s40883-018-0072-0] [Citation(s) in RCA: 73] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2017] [Accepted: 06/28/2018] [Indexed: 10/28/2022]
Abstract
Reconstruction of large bone defects resulting from trauma, neoplasm, or infection is a challenging problem in reconstructive surgery. The need for bone grafting has been increasing steadily partly because of our enhanced capability to salvage limbs after major bone loss. Engineered bone graft substitutes can have advantages such as lack of antigenicity, high availability, and varying properties depending on the applications chosen for use. These favorable attributes have contributed to the rise of scaffold-based polymeric tissue regeneration. Critical components in the scaffold-based polymeric regenerative engineering approach often include 1. The existence of biodegradable polymeric porous structures with properties selected to promote tissue regeneration and while providing appropriate mechanical support during tissue regeneration. 2. Cellular populations that can influence and enhance regeneration. 3. The use of growth and morphogenetic factors which can influence cellular migration, differentiation and tissue regeneration in vivo. Biodegradable polymers constitute an attractive class of biomaterials for the development of scaffolds due to their flexibility in chemistry and their ability to produce biocompatible degradation products. This paper presents an overview of polymeric scaffold-based bone tissue regeneration and reviews approaches as well as the particular roles of biodegradable polymers currently in use.
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Affiliation(s)
- Kenneth S. Ogueri
- Department of Materials Science and Engineering, University of Connecticut, Storrs, CT 06269, USA
- Institute for Regenerative Engineering, University of Connecticut Health Center, Farmington, CT 06030, USA
- Raymond and Beverly Sackler Center for Biomedical, Biological, Physical and Engineering Sciences, University of Connecticut Health Center, Farmington, CT 06030, USA
| | - Tahereh Jafari
- Institute for Regenerative Engineering, University of Connecticut Health Center, Farmington, CT 06030, USA
- Raymond and Beverly Sackler Center for Biomedical, Biological, Physical and Engineering Sciences, University of Connecticut Health Center, Farmington, CT 06030, USA
| | - Jorge L. Escobar Ivirico
- Institute for Regenerative Engineering, University of Connecticut Health Center, Farmington, CT 06030, USA
- Raymond and Beverly Sackler Center for Biomedical, Biological, Physical and Engineering Sciences, University of Connecticut Health Center, Farmington, CT 06030, USA
- Department of Chemical and Biomolecular Engineering, University of Connecticut, Storrs, CT 06269, USA
| | - Cato T. Laurencin
- Department of Materials Science and Engineering, University of Connecticut, Storrs, CT 06269, USA
- Institute for Regenerative Engineering, University of Connecticut Health Center, Farmington, CT 06030, USA
- Raymond and Beverly Sackler Center for Biomedical, Biological, Physical and Engineering Sciences, University of Connecticut Health Center, Farmington, CT 06030, USA
- Department of Orthopaedic Surgery, University of Connecticut Health Center, Farmington, CT 06030, USA
- Department of Biomedical Engineering, University of Connecticut, Storrs, CT 06269, USA
- Department of Chemical and Biomolecular Engineering, University of Connecticut, Storrs, CT 06269, USA
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Khan RU, Wang L, Yu H, Abdin ZU, Haq F, Haroon M, Naveed KUR, Elshaarani T, Fahad S, Ren S, Wang J. Synthesis of polyorganophosphazenes and fabrication of their blend microspheres and micro/nanofibers as drug delivery systems. INT J POLYM MATER PO 2019. [DOI: 10.1080/00914037.2019.1581203] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Affiliation(s)
- Rizwan Ullah Khan
- State Key Laboratory of Chemical Engineering, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou, P.R. China
| | - Li Wang
- State Key Laboratory of Chemical Engineering, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou, P.R. China
| | - Haojie Yu
- State Key Laboratory of Chemical Engineering, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou, P.R. China
| | - Zain-Ul- Abdin
- State Key Laboratory of Chemical Engineering, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou, P.R. China
| | - Fazal Haq
- State Key Laboratory of Chemical Engineering, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou, P.R. China
| | - Muhammad Haroon
- State Key Laboratory of Chemical Engineering, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou, P.R. China
| | - Kaleem-Ur-Rehman Naveed
- State Key Laboratory of Chemical Engineering, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou, P.R. China
| | - Tarig Elshaarani
- State Key Laboratory of Chemical Engineering, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou, P.R. China
| | - Shah Fahad
- State Key Laboratory of Chemical Engineering, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou, P.R. China
| | - Sicong Ren
- State Key Laboratory of Chemical Engineering, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou, P.R. China
| | - Jun Wang
- State Key Laboratory of Chemical Engineering, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou, P.R. China
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Song R, Murphy M, Li C, Ting K, Soo C, Zheng Z. Current development of biodegradable polymeric materials for biomedical applications. Drug Des Devel Ther 2018; 12:3117-3145. [PMID: 30288019 PMCID: PMC6161720 DOI: 10.2147/dddt.s165440] [Citation(s) in RCA: 386] [Impact Index Per Article: 64.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
In the last half-century, the development of biodegradable polymeric materials for biomedical applications has advanced significantly. Biodegradable polymeric materials are favored in the development of therapeutic devices, including temporary implants and three-dimensional scaffolds for tissue engineering. Further advancements have occurred in the utilization of biodegradable polymeric materials for pharmacological applications such as delivery vehicles for controlled/sustained drug release. These applications require particular physicochemical, biological, and degradation properties of the materials to deliver effective therapy. As a result, a wide range of natural or synthetic polymers able to undergo hydrolytic or enzymatic degradation is being studied for biomedical applications. This review outlines the current development of biodegradable natural and synthetic polymeric materials for various biomedical applications, including tissue engineering, temporary implants, wound healing, and drug delivery.
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Affiliation(s)
- Richard Song
- Division of Growth and Development, Section of Orthodontics, School of Dentistry, University of California, Los Angeles, Los Angeles, CA, USA,
| | - Maxwell Murphy
- Division of Growth and Development, Section of Orthodontics, School of Dentistry, University of California, Los Angeles, Los Angeles, CA, USA,
| | - Chenshuang Li
- Division of Growth and Development, Section of Orthodontics, School of Dentistry, University of California, Los Angeles, Los Angeles, CA, USA,
| | - Kang Ting
- Division of Growth and Development, Section of Orthodontics, School of Dentistry, University of California, Los Angeles, Los Angeles, CA, USA,
- UCLA Department of Surgery and Department of Orthopaedic Surgery and The Orthopaedic Hospital Research Center, University of California, Los Angeles, Los Angeles, CA, USA,
- UCLA Department of Bioengineering, School of Engineering, University of California, Los Angeles, Los Angeles, CA, USA
| | - Chia Soo
- UCLA Department of Surgery and Department of Orthopaedic Surgery and The Orthopaedic Hospital Research Center, University of California, Los Angeles, Los Angeles, CA, USA,
| | - Zhong Zheng
- Division of Growth and Development, Section of Orthodontics, School of Dentistry, University of California, Los Angeles, Los Angeles, CA, USA,
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Hou S, Chen S, Dong Y, Gao S, Zhu B, Lu Q. Biodegradable Cyclomatrix Polyphosphazene Nanoparticles: A Novel pH-Responsive Drug Self-Framed Delivery System. ACS APPLIED MATERIALS & INTERFACES 2018; 10:25983-25993. [PMID: 30014692 DOI: 10.1021/acsami.8b06114] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Traditional drug delivery systems suffer from low drug-loading and relatively weak therapeutic efficacy, therefore, development of new drug delivery systems with high-efficiency has become more urgent. In this report, a novel-innovative drug delivery strategy, namely drug self-framed delivery system (DSFDS), is prepared via using anticancer drugs as polymer frame without using any carriers. The drug molecules (exemplified by doxorubicin) containing more than two nucleophilic functional groups (diols/diamines) directly reacted with hexachlorocyclotriphosphazene via mild precipitation polycondensation under ambient conditions, forming biocompatible drug self-framed delivery nanoparticles. Because of the covalent bonding of the drug molecules, DSFD nanoparticles (DSFDs) with super high drug-loading were stable in the circulation during delivery. However, sustained release of drug in the acidic environment within cells endowed DSFDs with long-term anticancer therapeutic efficacy. This strategy is applicable for diverse hydrophilic and hydrophobic drugs and may be a new platform for designing high drug-loading and release-controllable drug delivery systems.
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Affiliation(s)
- Shenglei Hou
- School of Chemical Science and Engineering, The State Key Laboratory of Metal Matrix Composites , Shanghai Jiao Tong University , Shanghai 200240 , China
| | - Shuangshuang Chen
- School of Chemical Science and Engineering , Tongji University , Shanghai 200092 , China
| | - Yuan Dong
- School of Chemical Science and Engineering, The State Key Laboratory of Metal Matrix Composites , Shanghai Jiao Tong University , Shanghai 200240 , China
| | - Su Gao
- School of Chemical Science and Engineering, The State Key Laboratory of Metal Matrix Composites , Shanghai Jiao Tong University , Shanghai 200240 , China
| | - Bangshang Zhu
- School of Chemical Science and Engineering, The State Key Laboratory of Metal Matrix Composites , Shanghai Jiao Tong University , Shanghai 200240 , China
| | - Qinghua Lu
- School of Chemical Science and Engineering, The State Key Laboratory of Metal Matrix Composites , Shanghai Jiao Tong University , Shanghai 200240 , China
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Khan RU, Wang L, Yu H, Zain-ul-Abdin, Akram M, Wu J, Haroon M, Ullah RS, Deng Z, Xia X. Recent progress in the synthesis of poly(organo)phosphazenes and their applications in tissue engineering and drug delivery. RUSSIAN CHEMICAL REVIEWS 2018. [DOI: 10.1070/rcr4757] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Asafo-Adjei TA, Dziubla TD, Puleo DA. Tuning Properties of Poly(ethylene glycol)- block-poly(simvastatin) Copolymers Synthesized via Triazabicyclodecene. REACT FUNCT POLYM 2017; 119:37-46. [PMID: 29217967 DOI: 10.1016/j.reactfunctpolym.2017.07.004] [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] [Indexed: 11/28/2022]
Abstract
Simvastatin was polymerized into copolymers to better control drug loading and release for therapeutic delivery. When using the conventional stannous octoate catalyst in ring-opening polymerization (ROP), reaction temperatures ≥200 °C were required, which promoted uncontrollable and undesirable side reactions. Triazabicyclodecene (TBD), a highly reactive guanidine base organocatalyst, was used as an alternative to polymerize simvastatin. Polymerization was achieved at 150 °C using 5 kDa methyl-terminated poly(ethylene glycol) (mPEG) as the initiator. ROP reactions with 2 kDa or 550 Da mPEG initiators were also successful using TBD at 150 °C instead of stannous octoate, which required a higher reaction temperature. Biodegradability of the poly(simvastatin) copolymer in phosphate-buffered saline was also improved, losing twice as much mass than the copolymer synthesized via stannous octoate. The three copolymers exhibited modified rates of simvastatin release, demonstrating tunablity for drug delivery applications.
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Affiliation(s)
- Theodora A Asafo-Adjei
- F. Joseph Halcomb III, M.D. Department of Biomedical Engineering, University of Kentucky, Lexington, KY, USA
| | - Thomas D Dziubla
- Department of Chemical and Materials Engineering, University of Kentucky, Lexington, KY, USA
| | - David A Puleo
- F. Joseph Halcomb III, M.D. Department of Biomedical Engineering, University of Kentucky, Lexington, KY, USA
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Amin AM, Shahid SA, Li W, Haojie Y, Ali Z, Rehman H, Ghaffar A, Sarfraz M, Waqas M. An Efficient Synthesis, Structural Characterization and Hydrolytic Degradation Studies of Poly[bis(3-phenyl-1-propoxide amino benzoic acid diethylamino)phosphazene] as Potential Materials for Biomedical Applications. J Inorg Organomet Polym Mater 2017. [DOI: 10.1007/s10904-017-0533-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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10
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Ogueri KS, Escobar Ivirico JL, Nair LS, Allcock HR, Laurencin CT. Biodegradable Polyphosphazene-Based Blends for Regenerative Engineering. REGENERATIVE ENGINEERING AND TRANSLATIONAL MEDICINE 2017; 3:15-31. [PMID: 28596987 DOI: 10.1007/s40883-016-0022-7] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The occurrence of musculoskeletal tissue injury or disease and the subsequent functional impairment is at an alarming rate. It continues to be one of the most challenging problems in the human health care. Regenerative engineering offers a promising transdisciplinary strategy for tissues regeneration based on the convergence of tissue engineering, advanced materials science, stem cell science, developmental biology and clinical translation. Biomaterials are emerging as extracellular-mimicking matrices designed to provide instructive cues to control cell behavior and ultimately, be applied as therapies to regenerate damaged tissues. Biodegradable polymers constitute an attractive class of biomaterials for the development of scaffolds due to their flexibility in chemistry and the ability to be excreted or resorbed by the body. Herein, the focus will be on biodegradable polyphosphazene-based blend systems. The synthetic flexibility of polyphosphazene, combined with the unique inorganic backbone, has provided a springboard for more research and subsequent development of numerous novel materials that are capable of forming miscible blends with poly (lactide-co-glycolide) (PLAGA). Laurencin and co-workers has demonstrated the exploitation of the synthetic flexibility of Polyphosphazene that will allow the design of novel polymers, which can form miscible blends with PLAGA for biomedical applications. These novel blends, due to their well-tuned biodegradability, and mechanical and biological properties coupled with the buffering capacity of the degradation products, constitute ideal materials for regeneration of various musculoskeletal tissues. LAY SUMMARY Regenerative engineering aims to regenerate complex tissues to address the clinical challenge of organ damage. Tissue engineering has largely focused on the restoration and repair of individual tissues and organs, but over the past 25 years, scientific, engineering, and medical advances have led to the introduction of this new approach which involves the regeneration of complex tissues and biological systems such as a knee or a whole limb. While a number of excellent advanced biomaterials have been developed, the choice of biomaterials, however, has increased over the past years to include polymers that can be designed with a range of mechanical properties, degradation rates, and chemical functionality. The polyphosphazenes are one good example. Their chemical versatility and hydrogen bonding capability encourages blending with other biologically relevant polymers. The further development of Polyphosphazene-based blends will present a wide spectrum of advanced biomaterials that can be used as scaffolds for regenerative engineering and as well as other biomedical applications.
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Affiliation(s)
- Kenneth S Ogueri
- Department of Materials Science and Engineering, University of Connecticut, Storrs, CT 06269, USA.,Institute for Regenerative Engineering, University of Connecticut Health Center, Farmington, CT 06030, USA.,Raymond and Beverly Sackler Center for Biomedical, Biological, Physical and Engineering Sciences, University of Connecticut Health Center, Farmington, CT 06030, USA
| | - Jorge L Escobar Ivirico
- Institute for Regenerative Engineering, University of Connecticut Health Center, Farmington, CT 06030, USA.,Department of Orthopaedic Surgery, University of Connecticut Health Center, Farmington, CT 06030, USA.,Raymond and Beverly Sackler Center for Biomedical, Biological, Physical and Engineering Sciences, University of Connecticut Health Center, Farmington, CT 06030, USA
| | - Lakshmi S Nair
- Department of Materials Science and Engineering, University of Connecticut, Storrs, CT 06269, USA.,Institute for Regenerative Engineering, University of Connecticut Health Center, Farmington, CT 06030, USA.,Department of Orthopaedic Surgery, University of Connecticut Health Center, Farmington, CT 06030, USA.,Raymond and Beverly Sackler Center for Biomedical, Biological, Physical and Engineering Sciences, University of Connecticut Health Center, Farmington, CT 06030, USA.,Department of Biomedical Engineering, University of Connecticut, Storrs, CT 06269, USA
| | - Harry R Allcock
- Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania 16802, USA
| | - Cato T Laurencin
- Department of Materials Science and Engineering, University of Connecticut, Storrs, CT 06269, USA.,Institute for Regenerative Engineering, University of Connecticut Health Center, Farmington, CT 06030, USA.,Department of Orthopaedic Surgery, University of Connecticut Health Center, Farmington, CT 06030, USA.,Raymond and Beverly Sackler Center for Biomedical, Biological, Physical and Engineering Sciences, University of Connecticut Health Center, Farmington, CT 06030, USA.,Department of Biomedical Engineering, University of Connecticut, Storrs, CT 06269, USA.,Department of Chemical and Biomolecular Engineering, University of Connecticut, Storrs, CT 06269, USA
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11
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Huang Z, Yang L, Zhang X, Ruan B, Hu X, Deng X, Cai Q, Yang X. Synthesis and Fluorescent Property of Biodegradable Polyphosphazene Targeting Long-Term in Vivo Tracking. Macromolecules 2016. [DOI: 10.1021/acs.macromol.6b01976] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Affiliation(s)
- Zhaohui Huang
- State Key
Laboratory of Organic-Inorganic Composites, Beijing Laboratory of
Biomedical Materials, Beijing University of Chemical Technology, Beijing 100029, P. R. China
| | - Lika Yang
- State Key
Laboratory of Organic-Inorganic Composites, Beijing Laboratory of
Biomedical Materials, Beijing University of Chemical Technology, Beijing 100029, P. R. China
| | - Xuehui Zhang
- Department of Geriatric Dentistry, Peking University School and Hospital of Stomatology, Beijing 100081, P. R. China
| | - Bingyuan Ruan
- State Key
Laboratory of Organic-Inorganic Composites, Beijing Laboratory of
Biomedical Materials, Beijing University of Chemical Technology, Beijing 100029, P. R. China
| | - Xiaoqing Hu
- Institute of Sports Medicine, Beijing Key Laboratory
of Sports Injury, Peking University Third Hospital, Beijing 100191, P. R. China
| | - Xuliang Deng
- Department of Geriatric Dentistry, Peking University School and Hospital of Stomatology, Beijing 100081, P. R. China
| | - Qing Cai
- State Key
Laboratory of Organic-Inorganic Composites, Beijing Laboratory of
Biomedical Materials, Beijing University of Chemical Technology, Beijing 100029, P. R. China
| | - Xiaoping Yang
- State Key
Laboratory of Organic-Inorganic Composites, Beijing Laboratory of
Biomedical Materials, Beijing University of Chemical Technology, Beijing 100029, P. R. China
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12
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Qiu J, Wang Y, Liu Y, Zhang M, Wu Z, Liu C. A Ph-Sensitive Drug Carrier Based on Maleic Acid-Substituted Cyclotriphosphazene. PHOSPHORUS SULFUR 2015. [DOI: 10.1080/10426507.2014.999860] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Affiliation(s)
- Jinjun Qiu
- School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Wuhan, 430074, P.R. China
| | - Yu Wang
- School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Wuhan, 430074, P.R. China
| | - Yuanyuan Liu
- School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Wuhan, 430074, P.R. China
| | - Min Zhang
- Department of Material Science and Engineering, Northwestern University, Evanston, IL 60208, USA
| | - Zhangxin Wu
- School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Wuhan, 430074, P.R. China
| | - Chengmei Liu
- School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Wuhan, 430074, P.R. China
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13
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Akram M, Yu H, Wang L, Khalid H, Abbasi NM, Chen Y, Ren F, Saleem M. Sustained release of hydrophilic drug from polyphosphazenes/poly(methyl methacrylate) based microspheres and their degradation study. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 2015; 58:169-79. [PMID: 26478300 DOI: 10.1016/j.msec.2015.08.010] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/25/2015] [Revised: 06/15/2015] [Accepted: 08/10/2015] [Indexed: 11/18/2022]
Abstract
Drug delivery system is referred as an approach to deliver the therapeutic agents to the target site safely in order to achieve the maximum therapeutic effects. In this perspective, synthesis of three new polyphosphazenes and their blend fabrication system with poly(methyl methacrylate) is described and characterized with (1)H NMR, (31)P NMR, GPC and DSC. Furthermore, these novel blends were used to fabricate microspheres and evaluated for sustain release of hydrophilic drug (aspirin as model drug). Microspheres of the two blends showed excellent encapsulation efficacy (about 93%), controlled burst release (2.3% to 7.93%) and exhibited sustain in vitro drug release (13.44% to 32.77%) up to 218 h. At physiological conditions, the surface degradation of microspheres and diffusion process controlled the drug release sustainability. Furthermore, it was found that the degree of porosity was increased with degradation and the resulting porous network was responsible for water retention inside the microspheres. The percentage water retention was found to be interrelated with degradation time and percentage drug release.
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Affiliation(s)
- Muhammad Akram
- State Key Laboratory of Chemical Engineering, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou 310027, China
| | - Haojie Yu
- State Key Laboratory of Chemical Engineering, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou 310027, China.
| | - Li Wang
- State Key Laboratory of Chemical Engineering, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou 310027, China.
| | - Hamad Khalid
- State Key Laboratory of Chemical Engineering, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou 310027, China
| | - Nasir M Abbasi
- State Key Laboratory of Chemical Engineering, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou 310027, China
| | - Yongsheng Chen
- State Key Laboratory of Chemical Engineering, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou 310027, China
| | - Fujie Ren
- State Key Laboratory of Chemical Engineering, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou 310027, China
| | - Muhammad Saleem
- State Key Laboratory of Chemical Engineering, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou 310027, China
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14
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Chen C, Xu H, Qian YC, Huang XJ. Glycosylation of polyphosphazenes by thiol-yne click chemistry for lectin recognition. RSC Adv 2015. [DOI: 10.1039/c4ra14012e] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Strong carbohydrate–lectin binding interactions in biological systems can be mimicked through the synthesis of glucose containing macromolecules, particularly glycosylated polymers.
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Affiliation(s)
- Chen Chen
- MOE Key Laboratory of Macromolecular Synthesis and Functionalization
- Department of Polymer Science and Engineering
- Zhejiang University
- Hangzhou 310027
- China
| | - Huang Xu
- MOE Key Laboratory of Macromolecular Synthesis and Functionalization
- Department of Polymer Science and Engineering
- Zhejiang University
- Hangzhou 310027
- China
| | - Yue-Cheng Qian
- MOE Key Laboratory of Macromolecular Synthesis and Functionalization
- Department of Polymer Science and Engineering
- Zhejiang University
- Hangzhou 310027
- China
| | - Xiao-Jun Huang
- MOE Key Laboratory of Macromolecular Synthesis and Functionalization
- Department of Polymer Science and Engineering
- Zhejiang University
- Hangzhou 310027
- China
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15
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Shan D, Huang Z, Zhao Y, Cai Q, Yang X. Improving the miscibility of biodegradable polyester/polyphosphazene blends using cross-linkable polyphosphazene. ACTA ACUST UNITED AC 2014; 9:061001. [PMID: 25426734 DOI: 10.1088/1748-6041/9/6/061001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Biodegradable polyesters and polyphosphazenes are both promising biomaterials for tissue regeneration. A combination of both materials would provide additional advantages over the individual components in aspects of biocompatibility and osteocompatibility. Applications of polyester/polyphosphazene composites, however, were limited due to the severe phase separation. In this study, cross-linkable poly(glycine ethyl ester-co-hydroxyethyl methacrylate)phosphazene (PGHP) was synthesized. It was blended with poly(L-lactide) (PLLA) or poly(L-lactide-co-glycolide) (PLGA), using chloroform as a mutual solvent, and photo-crosslinked before solvent removal. The resulting PLLA (or PLGA)/PGHP composites demonstrated no significant phase separation due to the restricting function of the crosslinked PGHP polymeric network. In comparison with uncrosslinked blends, the mechanical properties of crosslinked composites were remarkably improved, which indicated their strong potential in bone regeneration applications.
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Affiliation(s)
- Dingying Shan
- Beijing Laboratory of Biomedical Materials, College of Material Science and Engineering, Beijing University of Chemical Technology, Beijing 100029, People's Republic of China
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16
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Ruan C, Hu Y, Jiang L, Cai Q, Pan H, Wang H. Tunable degradation of piperazine-based polyurethane ureas. J Appl Polym Sci 2014. [DOI: 10.1002/app.40527] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Changshun Ruan
- Center for Human Tissue and Organ Degeneration, Institute of Biomedicine and Biotechnology; Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences; Shenzhen 518055 China
- Shenzhen Key Laboratory of Marine Biomedical Materials; Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences; Shenzhen 518055 China
| | - Yang Hu
- Center for Human Tissue and Organ Degeneration, Institute of Biomedicine and Biotechnology; Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences; Shenzhen 518055 China
- Shenzhen Key Laboratory of Marine Biomedical Materials; Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences; Shenzhen 518055 China
| | - Lixin Jiang
- Center for Human Tissue and Organ Degeneration, Institute of Biomedicine and Biotechnology; Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences; Shenzhen 518055 China
- Shenzhen Key Laboratory of Marine Biomedical Materials; Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences; Shenzhen 518055 China
| | - Qingqing Cai
- Center for Human Tissue and Organ Degeneration, Institute of Biomedicine and Biotechnology; Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences; Shenzhen 518055 China
- Shenzhen Key Laboratory of Marine Biomedical Materials; Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences; Shenzhen 518055 China
| | - Haobo Pan
- Center for Human Tissue and Organ Degeneration, Institute of Biomedicine and Biotechnology; Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences; Shenzhen 518055 China
- Shenzhen Key Laboratory of Marine Biomedical Materials; Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences; Shenzhen 518055 China
| | - Huaiyu Wang
- Center for Human Tissue and Organ Degeneration, Institute of Biomedicine and Biotechnology; Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences; Shenzhen 518055 China
- Shenzhen Key Laboratory of Marine Biomedical Materials; Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences; Shenzhen 518055 China
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17
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Ruan C, Hu N, Hu Y, Jiang L, Cai Q, Wang H, Pan H, Lu WW, Wang Y. Piperazine-based polyurethane-ureas with controllable degradation as potential bone scaffolds. POLYMER 2014. [DOI: 10.1016/j.polymer.2014.01.011] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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18
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Hu L, Zhang A, Liu K, Lei S, Ou G, Cheng X. A facile method to prepare composite and porous polyphosphazene membranes and investigation of their properties. RSC Adv 2014. [DOI: 10.1039/c4ra05612d] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Polyphosphazene/SiO2 composite membranes and porous polyphosphazene membranes were prepared and their properties were studied in detail.
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Affiliation(s)
- Lei Hu
- School of Chemistry and Materials Science
- South-central University for Nationalities
- Wuhan, P. R. China
| | - Aiqing Zhang
- School of Chemistry and Materials Science
- South-central University for Nationalities
- Wuhan, P. R. China
| | - Kai Liu
- School of Chemistry and Materials Science
- South-central University for Nationalities
- Wuhan, P. R. China
| | - Shan Lei
- School of Chemistry and Materials Science
- South-central University for Nationalities
- Wuhan, P. R. China
| | - Guangxin Ou
- School of Chemistry and Materials Science
- South-central University for Nationalities
- Wuhan, P. R. China
| | - Xinjian Cheng
- School of Chemistry and Materials Science
- South-central University for Nationalities
- Wuhan, P. R. China
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19
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Ghaffar A, Schoenmakers PJ, van der Wal S. Methods for the Chemical Analysis of Degradable Synthetic Polymeric Biomaterials. Crit Rev Anal Chem 2013; 44:23-40. [DOI: 10.1080/10408347.2013.831729] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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20
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Hu Y, Meng L, Niu L, Lu Q. Highly cross-linked and biocompatible polyphosphazene-coated superparamagnetic Fe3O4 nanoparticles for magnetic resonance imaging. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2013; 29:9156-9163. [PMID: 23795597 DOI: 10.1021/la402119s] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Highly cross-linked and biocompatible poly(cyclotriphosphazene-co-4,4'-sulfonyldiphenol) (PZS) were used to directly coat hydrophilic superparamagnetic Fe3O4 nanoparticles by a facile but effective one-pot polycondensation. The obtained core-shell Fe3O4@PZS nanohybrids were characterized by transmission electron microscopy (TEM), scanning electron microscopy (SEM), Fourier-transform infrared (FTIR) and X-ray diffraction spectra. Interesting, the size and T2 relaxivity of Fe3O4@PZS increased with increasing the mass ratio of Fe3O4 to PZS. All these nanohybrids could be internalized by HeLa cells but show negligible cytotoxicity. The PZS layer slowly degraded into less dangerous forms such as 4,4'-sulfonyldiphenol, phosphate and ammonia at neutral or acid atmosphere. Considering their excellent water dispersibility, colloidal and chemical stability, magnetic manipulation, and magnetic resonance imaging (MRI) properties, Fe3O4@PZS nanohybrids have great potential in MRI diagnosis of cancer.
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Affiliation(s)
- Ying Hu
- School of Chemistry and Chemical Technology, Shanghai Jiao Tong University, Shanghai, 200240, P. R. China
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21
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Harmon MD, James R, Shelke NB, Kumbar SG. Synthesis and characterization of poly(caprolactone triol succinate) elastomer for tissue engineering application. J Appl Polym Sci 2013. [DOI: 10.1002/app.39633] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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22
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Amini AR, Laurencin CT, Nukavarapu SP. Bone tissue engineering: recent advances and challenges. Crit Rev Biomed Eng 2013; 40:363-408. [PMID: 23339648 DOI: 10.1615/critrevbiomedeng.v40.i5.10] [Citation(s) in RCA: 1341] [Impact Index Per Article: 121.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The worldwide incidence of bone disorders and conditions has trended steeply upward and is expected to double by 2020, especially in populations where aging is coupled with increased obesity and poor physical activity. Engineered bone tissue has been viewed as a potential alternative to the conventional use of bone grafts, due to their limitless supply and no disease transmission. However, bone tissue engineering practices have not proceeded to clinical practice due to several limitations or challenges. Bone tissue engineering aims to induce new functional bone regeneration via the synergistic combination of biomaterials, cells, and factor therapy. In this review, we discuss the fundamentals of bone tissue engineering, highlighting the current state of this field. Further, we review the recent advances of biomaterial and cell-based research, as well as approaches used to enhance bone regeneration. Specifically, we discuss widely investigated biomaterial scaffolds, micro- and nano-structural properties of these scaffolds, and the incorporation of biomimetic properties and/or growth factors. In addition, we examine various cellular approaches, including the use of mesenchymal stem cells (MSCs), embryonic stem cells (ESCs), adult stem cells, induced pluripotent stem cells (iPSCs), and platelet-rich plasma (PRP), and their clinical application strengths and limitations. We conclude by overviewing the challenges that face the bone tissue engineering field, such as the lack of sufficient vascularization at the defect site, and the research aimed at functional bone tissue engineering. These challenges will drive future research in the field.
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Affiliation(s)
- Ami R Amini
- Department of Orthopedic Surgery, University of Connecticut Health Center, Farmington, CT, USA
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23
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24
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Weikel AL, Lee DK, Krogman NR, Allcock HR. Phase changes of poly(alkoxyphosphazenes), and their behavior in the presence of oligoisobutylene. POLYM ENG SCI 2011. [DOI: 10.1002/pen.21623] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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25
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Amin AM, Wang L, Yu H, Amer WA, Gao J, Huo J, Tai Y, Zhang L. Synthesis and Characterization of Poly[bis(ethyl salicylate)phosphazenes] and Poly[bis(ethyl salicylate diethylamino)phosphazenes] and Their Hydrolytic Degradation. J Inorg Organomet Polym Mater 2011. [DOI: 10.1007/s10904-011-9529-z] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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26
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Nair LS, Bender JD, Singh A, Sethuraman S, Greish YE, Brown PW, Allcock HR, Laurencin CT. Biodegradable Poly[bis(ethyl alanato)phosphazene] - Poly(lactide-co-glycolide) Blends: Miscibility and Osteocompatibility Evaluations. ACTA ACUST UNITED AC 2011. [DOI: 10.1557/proc-844-y9.7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
ABSTRACTWe have previously demonstrated that blending biodegradable glycine co-substituted polyphosphazenes with poly(lactide-co-glycolide) (PLAGA) results in novel biomaterials with versatile properties. The study showed that the degradation rate of polyphosphazene/PLAGA blends can be effectively controlled by varying the blend composition while at the same time the degradation products of polyphosphazenes effectively neutralized the acidic degradation products of PLAGA. In the present study, novel blends of hydrophobic, biodegradable polyphosphazene, poly[bis(ethyl alanato) phosphazene] (PNEA) and PLAGA (LA: GA; 85:15) were developed as candidates for bone tissue engineering applications. Two different blend compositions were developed by blending PNEA and PLAGA having weight ratios of 25:75 (Blend-1) and 50:50 (Blend-2) by the mutual solvent technique using dichloromethane as the solvent. The miscibility of the blends was determined using differential scanning calorimetry (DSC), fourier transform-infrared spectroscopy (FT-IR), and scanning electron microscopy (SEM). Surface analysis of the blends by SEM revealed a smooth uniform surface for Blend-1, whereas Blend-2 showed evidence of phase separation. PNEA is not completely miscible with PLAGA, as evidenced from DSC and FT-IR measurements. The osteocompatibilities of Blend-1 and Blend-2 were compared to those of parent polymers by following the adhesion and proliferation of primary rat osteoblast cells on two dimensional (2-D) polymer and blend films over a 21 day period in culture. Blend films showed significantly higher cell numbers on the surface compared to PLAGA and PNEA films.
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27
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Liu W, Huang X, Wei H, Chen K, Gao J, Tang X. Facile preparation of hollow crosslinked polyphosphazene submicrospheres with mesoporous shells. ACTA ACUST UNITED AC 2011. [DOI: 10.1039/c1jm11802a] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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28
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Cai Q, Wang Y, Yang F, Shen H, Yang X, Wang S. Phase separation of polyphosphazene/poly(lactide-co
-glycolide) blends prepared under different conditions. POLYM ADVAN TECHNOL 2010. [DOI: 10.1002/pat.1783] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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29
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Sethuraman S, Nair LS, El-Amin S, Nguyen MT, Singh A, Krogman N, Greish YE, Allcock HR, Brown PW, Laurencin CT. Mechanical properties and osteocompatibility of novel biodegradable alanine based polyphosphazenes: Side group effects. Acta Biomater 2010; 6:1931-7. [PMID: 20004751 PMCID: PMC2862891 DOI: 10.1016/j.actbio.2009.12.012] [Citation(s) in RCA: 84] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2009] [Revised: 12/04/2009] [Accepted: 12/04/2009] [Indexed: 11/28/2022]
Abstract
The versatility of polymers for tissue regeneration lies in the feasibility to modulate the physical and biological properties by varying the side groups grafted to the polymers. Biodegradable polyphosphazenes are high-molecular-weight polymers with alternating nitrogen and phosphorus atoms in the backbone. This study is the first of its kind to systematically investigate the effect of side group structure on the compressive strength of novel biodegradable polyphosphazene based polymers as potential materials for tissue regeneration. The alanine polyphosphazene based polymers, poly(bis(ethyl alanato) phosphazene) (PNEA), poly((50% ethyl alanato) (50% methyl phenoxy) phosphazene) (PNEA(50)mPh(50)), poly((50% ethyl alanato) (50% phenyl phenoxy) phosphazene) (PNEA(50)PhPh(50)) were investigated to demonstrate their mechanical properties and osteocompatibility. Results of mechanical testing studies demonstrated that the nature and the ratio of the pendent groups attached to the polymer backbone play a significant role in determining the mechanical properties of the resulting polymer. The compressive strength of PNEA(50)PhPh(50) was significantly higher than poly(lactide-co-glycolide) (85:15 PLAGA) (p<0.05). Additional studies evaluated the cellular response and gene expression of primary rat osteoblast cells on PNEA, PNEA(50)mPh(50) and PNEA(50)PhPh(50) films as candidates for bone tissue engineering applications. Results of the in vitro osteocompatibility evaluation demonstrated that cells adhere, proliferate, and maintain their phenotype when seeded directly on the surface of PNEA, PNEA(50)mPh(50), and PNEA(50)PhPh(50). Moreover, cells on the surface of the polymers expressed type I collagen, alkaline phosphatase, osteocalcin, osteopontin, and bone sialoprotein, which are characteristic genes for osteoblast maturation, differentiation, and mineralization.
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Affiliation(s)
| | - Lakshmi S. Nair
- Department of Orthopaedic Surgery, University of Connecticut Health Center, Farmington, USA
- Department of Chemical, Materials and Biomolecular Engineering, University of Connecticut, Storrs, USA
| | - Saadiq El-Amin
- Department of Orthopaedic Surgery, Hospital for Special Surgery, New York, USA
| | - My-Tien Nguyen
- Department of Biology, University of Virginia, Charlottesville, USA
| | - Anurima Singh
- Department of Chemistry, Pennsylvania State University, University Park, USA
| | - Nick Krogman
- Department of Chemistry, Pennsylvania State University, University Park, USA
| | - Yaser E. Greish
- Materials Research Institute Pennsylvania State University, University Park, USA
| | - Harry R. Allcock
- Department of Chemistry, Pennsylvania State University, University Park, USA
| | - Paul W. Brown
- Materials Research Institute Pennsylvania State University, University Park, USA
| | - Cato T. Laurencin
- Department of Orthopaedic Surgery, University of Connecticut Health Center, Farmington, USA
- Department of Chemical, Materials and Biomolecular Engineering, University of Connecticut, Storrs, USA
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30
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Deng M, Nair LS, Nukavarapu SP, Jiang T, Kanner WA, Li X, Kumbar SG, Weikel AL, Krogman NR, Allcock HR, Laurencin CT. Dipeptide-based polyphosphazene and polyester blends for bone tissue engineering. Biomaterials 2010; 31:4898-908. [PMID: 20334909 DOI: 10.1016/j.biomaterials.2010.02.058] [Citation(s) in RCA: 80] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2010] [Accepted: 02/23/2010] [Indexed: 11/19/2022]
Abstract
Polyphosphazene-polyester blends are attractive materials for bone tissue engineering applications due to their controllable degradation pattern with non-toxic and neutral pH degradation products. In our ongoing quest for an ideal completely miscible polyphosphazene-polyester blend system, we report synthesis and characterization of a mixed-substituent biodegradable polyphosphazene poly[(glycine ethyl glycinato)(1)(phenyl phenoxy)(1)phosphazene] (PNGEG/PhPh) and its blends with a polyester. Two dipeptide-based blends namely 25:75 (Matrix1) and 50:50 (Matrix2) were produced at two different weight ratios of PNGEG/PhPh to poly(lactic acid-glycolic acid) (PLAGA). Blend miscibility was confirmed by differential scanning calorimetry, Fourier transform infrared spectroscopy, and scanning electron microscopy. Both blends resulted in higher tensile modulus and strength than the polyester. The blends showed a degradation rate in the order of Matrix2<Matrix1<PLAGA in phosphate buffered saline at 37 degrees C over 12 weeks. Significantly higher pH values of degradation media were observed for blends compared to PLAGA confirming the neutralization of PLAGA acidic degradation by polyphosphazene hydrolysis products. The blend components PLAGA and polyphosphazene exhibited a similar degradation pattern as characterized by the molecular weight loss. Furthermore, blends demonstrated significantly higher osteoblast growth rates compared to PLAGA while maintaining osteoblast phenotype over a 21-day culture. Both blends demonstrated improved biocompatibility in a rat subcutaneous implantation model compared to PLAGA over 12 weeks.
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Affiliation(s)
- Meng Deng
- Department of Orthopaedic Surgery, University of Connecticut, Farmington, CT 06030-3800, USA
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31
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Deng M, Nair LS, Nukavarapu SP, Kumbar SG, Brown JL, Krogman NR, Weikel AL, Allcock HR, Laurencin CT. Biomimetic, bioactive etheric polyphosphazene-poly(lactide-co-glycolide) blends for bone tissue engineering. J Biomed Mater Res A 2010; 92:114-25. [DOI: 10.1002/jbm.a.32334] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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32
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Shah PN, Lopina ST, Yun YH. Blends of novel L-tyrosine-based polyurethanes and polyphosphate for potential biomedical applications. J Appl Polym Sci 2009. [DOI: 10.1002/app.30509] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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33
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34
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Zhang C, Wen X, Vyavahare NR, Boland T. Synthesis and characterization of biodegradable elastomeric polyurethane scaffolds fabricated by the inkjet technique. Biomaterials 2008; 29:3781-91. [DOI: 10.1016/j.biomaterials.2008.06.009] [Citation(s) in RCA: 82] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2008] [Accepted: 06/07/2008] [Indexed: 11/25/2022]
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35
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Sohier J, Moroni L, van Blitterswijk C, de Groot K, Bezemer JM. Critical factors in the design of growth factor releasing scaffolds for cartilage tissue engineering. Expert Opin Drug Deliv 2008; 5:543-66. [PMID: 18491981 DOI: 10.1517/17425247.5.5.543] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
BACKGROUND Trauma or degenerative diseases of the joints are common clinical problems resulting in high morbidity. Although various orthopedic treatments have been developed and evaluated, the low repair capacities of articular cartilage renders functional results unsatisfactory in the long term. Over the last decade, a different approach (tissue engineering) has emerged that aims not only to repair impaired cartilage, but also to fully regenerate it, by combining cells, biomaterials mimicking extracellular matrix (scaffolds) and regulatory signals. The latter is of high importance as growth factors have the potency to induce, support or enhance the growth and differentiation of various cell types towards the chondrogenic lineage. Therefore, the controlled release of different growth factors from scaffolds appears to have great potential to orchestrate tissue repair effectively. OBJECTIVE This review aims to highlight considerations and limitations of the design, materials and processing methods available to create scaffolds, in relation to the suitability to incorporate and release growth factors in a safe and defined manner. Furthermore, the current state of the art of signalling molecules release from scaffolds and the impact on cartilage regeneration in vitro and in vivo is reported and critically discussed. METHODS The strict aspects of biomaterials, scaffolds and growth factor release from scaffolds for cartilage tissue engineering applications are considered. CONCLUSION Engineering defined scaffolds that deliver growth factors in a controlled way is a task seldom attained. If growth factor delivery appears to be beneficial overall, the optimal delivery conditions for cartilage reconstruction should be more thoroughly investigated.
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Affiliation(s)
- J Sohier
- Laboratory for osteo-articular and dental tissue engineering (LIOAD), Faculté de chirurgie dentaire de Nantes, Inserm U791, 1 Place Alexis Ricordeau, 44042 Nantes Cedex 1, France.
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Moroni L, de Wijn JR, van Blitterswijk CA. Integrating novel technologies to fabricate smart scaffolds. JOURNAL OF BIOMATERIALS SCIENCE-POLYMER EDITION 2008; 19:543-72. [PMID: 18419938 DOI: 10.1163/156856208784089571] [Citation(s) in RCA: 166] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Tissue engineering aims at restoring or regenerating a damaged tissue by combining cells, derived from a patient biopsy, with a 3D porous matrix functioning as a scaffold. After isolation and eventual in vitro expansion, cells are seeded on the 3D scaffolds and implanted directly or at a later stage in the patient's body. 3D scaffolds need to satisfy a number of requirements: (i) biocompatibility, (ii) biodegradability and/or bioresorbability, (iii) suitable mechanical properties, (iv) adequate physicochemical properties to direct cell-material interactions matching the tissue to be replaced and (v) ease in regaining the original shape of the damaged tissue and the integration with the surrounding environment. Still, it appears to be a challenge to satisfy all the aforementioned requisites with the biomaterials and the scaffold fabrication technologies nowadays available. 3D scaffolds can be fabricated with various techniques, among which rapid prototyping and electrospinning seem to be the most promising. Rapid prototyping technologies allow manufacturing scaffolds with a controlled, completely accessible pore network--determinant for nutrient supply and diffusion--in a CAD/CAM fashion. Electrospinning (ESP) allows mimicking the extracellular matrix (ECM) environment of the cells and can provide fibrous scaffolds with instructive surface properties to direct cell faith into the proper lineage. Yet, these fabrication methods have some disadvantages if considered alone. This review aims at summarizing conventional and novel scaffold fabrication techniques and the biomaterials used for tissue engineering and drug-delivery applications. A new trend seems to emerge in the field of scaffold design where different scaffolds fabrication technologies and different biomaterials are combined to provide cells with mechanical, physicochemical and biological cues at the macro-, micro- and nano-scale. If merged together, these integrated technologies may lead to the generation of a new set of 3D scaffolds that satisfies all of the scaffolds' requirements for tissue-engineering applications and may contribute to their success in a long-term scenario.
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Affiliation(s)
- L Moroni
- Institute for BioMedical Technology (BMTI), University of Twente, P.O. Box 217, 7500 AE Enschede, The Netherlands.
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37
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Loading dependent swelling and release properties of novel biodegradable, elastic and environmental stimuli-sensitive polyurethanes. J Control Release 2008; 131:128-36. [PMID: 18703098 DOI: 10.1016/j.jconrel.2008.07.026] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2008] [Revised: 07/11/2008] [Accepted: 07/20/2008] [Indexed: 12/24/2022]
Abstract
A novel degradable, elastic, anionic, and linear polyurethane was synthesized from hexamethylene diisocyanate, polycaprolactone diol, and a bicine chain extender. The chemical structure, mechanical properties, degradation rate, and swelling ratio were characterized by comparing the polymer with a polyurethane containing a 2,2-(methylimino) diethanol chain extender. Due to the incorporation of negatively charged carboxyl side groups, the bicine extended polymers exhibited higher micro-phase separation, better mechanical properties in dry condition, and better sensitivity to environmental stimuli than controls, as demonstrated by its high swelling ratio at elevated pH, lower ionic strength, or higher temperature. The swelling ratio of membranes showed reversible change as the function of pH at 37 degrees C, the membranes becoming fully water soluble at pH above 8.3. Nile blue chloride and lysozyme were selected to study their release from this polymer. The release rates of both compounds were significantly influenced by the pH and ionic strength. The swelling ratios were also influenced by lysozyme loading at low pH. The pH dependent properties were used to fabricate scaffolds by drop-on-demand printing. Bicine extended polyurethanes may be of interest for possible drug delivery applications, customizable scaffold fabrication and other potential biomedical applications.
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SYNTHESIS AND CHARACTERIZATION OF POLY(BIS(2-METHOXYETHOXY)PHOSPHAZENE)-GRAFT-POLY(ε-CAPROLACTONE) COPOLYMERS. ACTA POLYM SIN 2008. [DOI: 10.3724/sp.j.1105.2008.00088] [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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39
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Miscibility and in vitro osteocompatibility of biodegradable blends of poly[(ethyl alanato) (p-phenyl phenoxy) phosphazene] and poly(lactic acid-glycolic acid). Biomaterials 2007; 29:337-49. [PMID: 17942150 DOI: 10.1016/j.biomaterials.2007.09.029] [Citation(s) in RCA: 79] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2007] [Accepted: 09/23/2007] [Indexed: 11/20/2022]
Abstract
Previously we demonstrated the ability of ethyl glycinato substituted polyphosphazenes to neutralize the acidic degradation products and control the degradation rate of poly(lactic acid-glycolic acid) (PLAGA) by blending. In this study, blends of high strength poly[(50% ethyl alanato) (50% p-phenyl phenoxy) phosphazene] (PNEA(50)PhPh(50)) and 85:15 PLAGA were prepared using a mutual solvent approach. Three different solvents, methylene chloride (MC), chloroform (CF) and tetrahydrofuran (THF) were studied to investigate solvent effects on blend miscibility. Three different blends were then fabricated at various weight ratios namely 25:75 (BLEND25), 50:50 (BLEND50), and 75:25 (BLEND75) using THF as the mutual solvent. The miscibility of the blends was evaluated by scanning electron microscopy (SEM), differential scanning calorimetry (DSC), and Fourier transform infrared spectroscopy (FTIR). Among these, BLEND25 was miscible while BLEND50 and BLEND75 were partially miscible. Furthermore, BLEND25 formed apatite layers on its surface as evidenced in a biomimetic study performed. These novel blends showed cell adhesion and proliferation comparable to PLAGA. However, the PNEA(50)PhPh(50) component in the blends was able to increase the phenotypic expression and mineralized matrix synthesis of the primary rat osteoblasts (PRO) in vitro. Blends of high strength PNEA(50)PhPh(50) and 85:15 PLAGA are promising biomaterials for a variety of musculoskeletal applications.
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Applications of Inorganic Polymeric Materials, III: Polyphosphazenes. MONATSHEFTE FUR CHEMIE 2007. [DOI: 10.1007/s00706-007-0705-3] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Yin L, Huang X, Tang X. Synthesis, characterization and hydrolytic degradation of linear and crosslinked poly[(glycino ethyl ester)(allyl amino)phosphazene]. Polym Degrad Stab 2007. [DOI: 10.1016/j.polymdegradstab.2007.02.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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The Biocompatibility of Biodegradable Glycine Containing Polyphosphazenes: A Comparative study in Bone. J Inorg Organomet Polym Mater 2007. [DOI: 10.1007/s10904-006-9096-x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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45
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Yuan W, Yuan J, Huang X, Tang X. Synthesis, characterization, andin vitro degradation of star-shaped P(ɛ-caprolactone)-b-poly(L-lactide)-b-poly(D,L-lactide-co-glycolide) from hexakis [p-(hydroxymethyl)phenoxy]cyclotriphosphazene initiator. J Appl Polym Sci 2007. [DOI: 10.1002/app.25699] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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In Vitro and In Vivo Characterization of Biodegradable Poly(organophosphazenes) for Biomedical Applications. J Inorg Organomet Polym Mater 2006. [DOI: 10.1007/s10904-006-9071-6] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/29/2022]
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Wang Y, Kim HJ, Vunjak-Novakovic G, Kaplan DL. Stem cell-based tissue engineering with silk biomaterials. Biomaterials 2006; 27:6064-82. [PMID: 16890988 DOI: 10.1016/j.biomaterials.2006.07.008] [Citation(s) in RCA: 605] [Impact Index Per Article: 33.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2006] [Accepted: 07/06/2006] [Indexed: 12/27/2022]
Abstract
Silks are naturally occurring polymers that have been used clinically as sutures for centuries. When naturally extruded from insects or worms, silk is composed of a filament core protein, termed fibroin, and a glue-like coating consisting of sericin proteins. In recent years, silk fibroin has been increasingly studied for new biomedical applications due to the biocompatibility, slow degradability and remarkable mechanical properties of the material. In addition, the ability to now control molecular structure and morphology through versatile processability and surface modification options have expanded the utility for this protein in a range of biomaterial and tissue-engineering applications. Silk fibroin in various formats (films, fibers, nets, meshes, membranes, yarns, and sponges) has been shown to support stem cell adhesion, proliferation, and differentiation in vitro and promote tissue repair in vivo. In particular, stem cell-based tissue engineering using 3D silk fibroin scaffolds has expanded the use of silk-based biomaterials as promising scaffolds for engineering a range of skeletal tissues like bone, ligament, and cartilage, as well as connective tissues like skin. To date fibroin from Bombyx mori silkworm has been the dominant source for silk-based biomaterials studied. However, silk fibroins from spiders and those formed via genetic engineering or the modification of native silk fibroin sequence chemistries are beginning to provide new options to further expand the utility of silk fibroin-based materials for medical applications.
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Affiliation(s)
- Yongzhong Wang
- Department of Chemical and Biological Engineering, Tufts University, 4 Colby Street, Medford, MA 02155, USA
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Zhang C, Zhang N, Wen X. Improving the elasticity and cytophilicity of biodegradable polyurethane by changing chain extender. J Biomed Mater Res B Appl Biomater 2006; 79:335-44. [PMID: 16767730 DOI: 10.1002/jbm.b.30547] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Two types of biodegradable polyurethanes (PUs) were synthesized from methylene di-p-phenyl-diisocyanate (MDI), polycaprolactone diol (PCL-diol), and chain extenders of either butanediol (BD) or 2,2'-(methylimino)diethanol (MIDE). The effects of two types of chain extenders on the degradation, mechanical properties, hydrophilicity, and cytophilicity of PUs were evaluated. In vitro degradation studies showed that PU containing MIDE has a higher degradation rate than PU synthesized using BD as a chain extender. Mechanical testing on dry and wet samples demonstrated that PU containing MIDE has a much higher elongation in the elastic region than PU containing BD. PU containing MIDE is more hydrophilic and retains more liquid during in vitro culture. Furthermore, preliminary cytocompatibility studies showed that both types of degradable PU are nontoxic, and fibroblasts adhere better and proliferate faster on MIDE containing PU than BD containing PU. To compare the cytocompatibility and degradation behaviors of the synthesized PU with existing FDA approved biocompatible material, polylactide (PLA), with a similar degradation rate, was used as negative control. Two types of PU were shown to have similar cytocompatibility and degradation behaviors as those of the PLA material. To verify the effectiveness of the cytotoxicity assay, latex was used as a positive control. Latex samples showed toxicity to cultured cells as expected. In conclusion, by changing the type of chain extender used during the synthesis of degradable PUs, the degradation rate, mechanical properties, hydrophilicity, and cytophilicity can be adjusted for different tissue engineering applications.
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Affiliation(s)
- Changhong Zhang
- Clemson-MUSC Bioengineering program, Department of Bioengineering, Clemson University, Charleston, SC 29425, USA
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Andrianov AK, Marin A. Degradation of polyaminophosphazenes: effects of hydrolytic environment and polymer processing. Biomacromolecules 2006; 7:1581-6. [PMID: 16677042 DOI: 10.1021/bm050959k] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Polyphosphazenes with amino acid ester side groups show potential as hydrolytically degradable materials for biomedical applications. This study focuses on practical aspects of their use as biodegradable materials, such as effects of the hydrolytic environment and sample processing. Poly[di(ethyl glycinato)phosphazene], PEGP, and poly[di(ethyl alaninato)phosphazene], PEAP, were prepared by macromolecular substitution reaction, ensuring the absence of the residual chlorine atoms to avoid their influence on the hydrolysis. The kinetics of polymer degradation was studied by simultaneously measuring polymer mass loss, molecular weight decrease, and the release of phosphates and ammonia. The effect of pH, buffer composition, temperature, casting solvents, and film thickness were investigated.
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Conconi MT, Lora S, Menti AM, Carampin P, Parnigotto PP. In vitro evaluation of poly[bis(ethyl alanato)phosphazene] as a scaffold for bone tissue engineering. ACTA ACUST UNITED AC 2006; 12:811-9. [PMID: 16674294 DOI: 10.1089/ten.2006.12.811] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Polyphosphazenes with amino acid ester as side groups are biocompatible polymers that could provide valid scaffolds for cell growth. In the present study we investigate the adhesion and growth of osteoblasts obtained from rat bone marrow on matrices composed of thin fibers of poly[bis(ethyl alanato)phosphazene] (PAlaP), poly(d,l-lactic acid) (PDLLA), or PAlaP/PDLLA blend. Our data show that scaffolds of PAlaP or PAlaP/PDLLA blend enhanced the cell adhesion and growth in comparison with that observed in cultures seeded on polystyrene tissue culture plates. Although collagenase-digestible protein synthesis remained unchanged, all scaffolds induced a decrease in alkaline phosphatase activity, suggesting that osteoblasts are in the proliferation phase. Both PAlaP and PAlaP blended with PDLLA may represent a new and interesting substrate for bone tissue engineering.
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