101
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Wilkinson AE, McCormick AM, Leipzig ND. Central Nervous System Tissue Engineering: Current Considerations and Strategies. ACTA ACUST UNITED AC 2011. [DOI: 10.2200/s00390ed1v01y201111tis008] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
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102
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Severino P, Santana MHA, Malmonge SM, Souto EB. Polímeros usados como sistemas de transporte de princípios ativos. POLIMEROS 2011. [DOI: 10.1590/s0104-14282011005000061] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Os diferentes sistemas de transporte têm evidenciado potencial terapêutico para uma grande variedade de princípios ativos, satisfazendo vários requisitos, como a prevenção da sua eliminação rápida do organismo, a redução da sua toxicidade sistêmica, a estabilização e a otimização do seu metabolismo, e o direcionamento específico ao local alvo e os mecanismos de defesa. No entanto, têm sido reconhecidos vários outros desafios associados à liberação específica do princípio ativo ao local alvo, pelo que, para ultrapassar os obstáculos químicos e biológicos, a seleção do polímero utilizado para a preparação do sistema de transporte é de importância crucial. O presente trabalho apresenta um relato sobre os principais polímeros naturais e sintéticos utilizados para a preparação de sistemas de transporte de princípios ativos in vivo.
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103
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Tsai PH, Wang CH, Kan LS, Chen CW. Studies on the optimal conditions for synthesizing poly(butylene succinate-co-terephthalate) copolyesters with targeted properties. ASIA-PAC J CHEM ENG 2011. [DOI: 10.1002/apj.645] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Ping-Hsun Tsai
- Department of Bioengineering; Tatung University; Taipei 10452 Taiwan, ROC
| | - Ching-Huang Wang
- Department of Bioengineering; Tatung University; Taipei 10452 Taiwan, ROC
| | - Lou-Sing Kan
- Department of Bioengineering; Tatung University; Taipei 10452 Taiwan, ROC
- Institute of Chemistry; Academia Sinica; Taipei 11529 Taiwan, ROC
| | - C. Will Chen
- Department of Bioengineering; Tatung University; Taipei 10452 Taiwan, ROC
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104
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Activation of innate immune responses in a pathogen-mimicking manner by amphiphilic polyanhydride nanoparticle adjuvants. Biomaterials 2011; 32:6815-22. [DOI: 10.1016/j.biomaterials.2011.05.063] [Citation(s) in RCA: 107] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2011] [Accepted: 05/20/2011] [Indexed: 11/22/2022]
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105
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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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106
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Polyanhydride microparticles enhance dendritic cell antigen presentation and activation. Acta Biomater 2011; 7:2857-64. [PMID: 21439412 DOI: 10.1016/j.actbio.2011.03.023] [Citation(s) in RCA: 89] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2010] [Revised: 03/09/2011] [Accepted: 03/16/2011] [Indexed: 12/20/2022]
Abstract
The present study was designed to evaluate the adjuvant activity of polyanhydride microparticles prepared in the absence of additional stabilizers, excipients or immune modulators. Microparticles composed of varying ratios of either 1,6-bis(p-carboxyphenoxy)hexane (CPH) and sebacic acid or 1,8-bis(p-carboxyphenoxy)-3,6-dioxaoctane and CPH were added to in vitro cultures of bone marrow-derived dendritic cells (DCs). Microparticles were efficiently and rapidly phagocytosed by DCs in the absence of opsonization and without centrifugation or agitation. Within 2h, internalized particles were rapidly localized to an acidic, phagolysosomal compartment. By 48 h, only a minor reduction in microparticle size was observed in the phagolysosomal compartment, indicating minimal particle erosion consistent with being localized within an intracellular microenvironment favoring particle stability. Polyanhydride microparticles increased DC surface expression of major histocompatability complex class II, the co-stimulatory molecules CD86 and CD40, and the C-type lectin CIRE (murine DC-SIGN; CD209). In addition, microparticle stimulation of DCs also enhanced secretion of the cytokines IL-12p40 and IL-6, a phenomenon found to be dependent on polymer chemistry. DCs cultured with polyanhydride microparticles and ovalbumin induced polymer chemistry-dependent antigen-specific proliferation of both CD4(+) OT-II and CD8(+) OT-I T cells. These data indicate that polyanhydride particles can be tailored to take advantage of the potential plasticity of the immune response, resulting in the ability to induce immune protection against many types of pathogens.
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107
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Ulery BD, Nair LS, Laurencin CT. Biomedical Applications of Biodegradable Polymers. JOURNAL OF POLYMER SCIENCE. PART B, POLYMER PHYSICS 2011; 49:832-864. [PMID: 21769165 PMCID: PMC3136871 DOI: 10.1002/polb.22259] [Citation(s) in RCA: 1185] [Impact Index Per Article: 91.2] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Utilization of polymers as biomaterials has greatly impacted the advancement of modern medicine. Specifically, polymeric biomaterials that are biodegradable provide the significant advantage of being able to be broken down and removed after they have served their function. Applications are wide ranging with degradable polymers being used clinically as surgical sutures and implants. In order to fit functional demand, materials with desired physical, chemical, biological, biomechanical and degradation properties must be selected. Fortunately, a wide range of natural and synthetic degradable polymers has been investigated for biomedical applications with novel materials constantly being developed to meet new challenges. This review summarizes the most recent advances in the field over the past 4 years, specifically highlighting new and interesting discoveries in tissue engineering and drug delivery applications.
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Affiliation(s)
- Bret D. Ulery
- Department of Orthopaedic Surgery, New England Musculoskeletal Institute, University of Connecticut Health Center, Farmington, Connecticut 06030
- Institute of Regenerative Engineering, University of Connecticut Health Center, Farmington, Connecticut 06030
| | - Lakshmi S. Nair
- Department of Orthopaedic Surgery, New England Musculoskeletal Institute, University of Connecticut Health Center, Farmington, Connecticut 06030
- Institute of Regenerative Engineering, University of Connecticut Health Center, Farmington, Connecticut 06030
- Department of Chemical, Materials & Biomolecular Engineering, University of Connecticut, Storrs, Connecticut 06268
| | - Cato T. Laurencin
- Department of Orthopaedic Surgery, New England Musculoskeletal Institute, University of Connecticut Health Center, Farmington, Connecticut 06030
- Institute of Regenerative Engineering, University of Connecticut Health Center, Farmington, Connecticut 06030
- Department of Chemical, Materials & Biomolecular Engineering, University of Connecticut, Storrs, Connecticut 06268
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108
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Hong DW, Liu TH, Chu IM. Encapsulation of curcumin by methoxy poly(ethylene glycol-b-aromatic anhydride) micelles. J Appl Polym Sci 2011. [DOI: 10.1002/app.34191] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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109
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Bat E, van Kooten TG, Feijen J, Grijpma DW. Resorbable elastomeric networks prepared by photocrosslinking of high-molecular-weight poly(trimethylene carbonate) with photoinitiators and poly(trimethylene carbonate) macromers as crosslinking aids. Acta Biomater 2011; 7:1939-48. [PMID: 21232640 DOI: 10.1016/j.actbio.2011.01.010] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2010] [Revised: 12/14/2010] [Accepted: 01/07/2011] [Indexed: 10/18/2022]
Abstract
Resorbable and elastomeric poly(trimethylene carbonate) (PTMC) networks were efficiently prepared by photoinitiated crosslinking of linear high-molecular-weight PTMC. To crosslink PTMC films, low-molecular-weight PTMC macromers with methacrylate end groups were synthesized and used as crosslinking aids. By exposing PTMC films containing only photoinitiator (Irgacure(®) 2959) or both photoinitiator and PTMC macromers to ultraviolet light, PTMC networks with high gel contents (87-95%) could be obtained. The crosslink density could be readily varied by adjusting the irradiation time or the amount of crosslinking aid used. The formed networks were flexible, with low elastic modulus values ranging from 7.1 to 7.5MPa, and also showed excellent resistance to creep in cyclic tests. In vitro experiments showed that the photocrosslinked PTMC networks could be eroded by macrophages, and upon incubation in aqueous cholesterol esterase enzyme- or potassium dioxide solutions. The rate of surface erosion of photocrosslinked PTMC networks was significantly lower than that observed for films prepared from linear PTMC. These resorbable PTMC elastomeric networks are compatible with cells and may find application in tissue engineering and controlled release.
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110
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Shikanov A, Shikanov S, Vaisman B, Golenser J, Domb AJ. Cisplatin tumor biodistribution and efficacy after intratumoral injection of a biodegradable extended release implant. CHEMOTHERAPY RESEARCH AND PRACTICE 2011; 2011:175054. [PMID: 22295203 PMCID: PMC3265254 DOI: 10.1155/2011/175054] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/01/2010] [Revised: 11/26/2010] [Accepted: 01/11/2011] [Indexed: 11/23/2022]
Abstract
Local delivery of chemotherapeutic drugs has long been recognized as a potential method for reaching high drug doses at the target site while minimizing systemic exposure. Cisplatin is one of the most effective chemotherapeutic agents for the treatment of various tumors; however, its systemic toxicity remains the primary dose-limiting factor. Here we report that incorporation of cisplatin into a fatty acid-based polymer carrier followed by a local injection into the solid tumor resulted in a successful tumor growth inhibition in heterotopic mouse bladder tumor model in mice. Platinum concentration in the tumor tissue surrounding the injected implant remained above the therapeutic level up to 14 days after the injection, while the plasma levels were several orders of magnitude lower comparing to systemic delivery. The reported delivery system increased the maximum tolerated dose of cisplatin 5 times compared to systemic delivery, thus potentially improving antitumor efficacy of cisplatin in solid tumor model.
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Affiliation(s)
- Ariella Shikanov
- Department of Medicinal Chemistry and Natural Products, School of Pharmacy, The Hebrew University of Jerusalem, 91120 Jerusalem, Israel
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111
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Li X, Petersen L, Broderick S, Narasimhan B, Rajan K. Identifying factors controlling protein release from combinatorial biomaterial libraries via hybrid data mining methods. ACS COMBINATORIAL SCIENCE 2011; 13:50-8. [PMID: 21247125 DOI: 10.1021/co100019d] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Polyanhydrides are a class of degradable biomaterials that have shown much promise for applications in drug and vaccine delivery. Their properties can be tailored for controlled drug release, drug/protein stability, and immune regulation (adjuvant effect). Identifying the relationship between the molecular structures of the polymers and the drug release kinetics profiles would help understand the release mechanism and aid in the accurate prediction of drug release and the rational design of polymer-based drug carrier systems. The molecular structure descriptors that had the most impact on the release kinetics were identified using a prediction/optimization data mining approach. Using this new approach for modeling nonlinear release kinetics behavior, we determined that the descriptors which had the greatest effect on the release kinetics were the number of backbone -COO- nonconjugated bonds, the number of aromatic rings, and the number of -CH₂- bonds.
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Affiliation(s)
- Xue Li
- Institute for Combinatorial Discovery, Department of Materials Science and Engineering, and Department of Chemical and Biological Engineering, Iowa State University, Ames, Iowa 50011, United States
| | - Latrisha Petersen
- Institute for Combinatorial Discovery, Department of Materials Science and Engineering, and Department of Chemical and Biological Engineering, Iowa State University, Ames, Iowa 50011, United States
| | - Scott Broderick
- Institute for Combinatorial Discovery, Department of Materials Science and Engineering, and Department of Chemical and Biological Engineering, Iowa State University, Ames, Iowa 50011, United States
| | - Balaji Narasimhan
- Institute for Combinatorial Discovery, Department of Materials Science and Engineering, and Department of Chemical and Biological Engineering, Iowa State University, Ames, Iowa 50011, United States
| | - Krishna Rajan
- Institute for Combinatorial Discovery, Department of Materials Science and Engineering, and Department of Chemical and Biological Engineering, Iowa State University, Ames, Iowa 50011, United States
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112
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Gao J, Bao F, Feng L, Shen K, Zhu Q, Wang D, Chen T, Ma R, Yan C. Functionalized graphene oxide modified polysebacic anhydride as drug carrier for levofloxacin controlled release. RSC Adv 2011. [DOI: 10.1039/c1ra00029b] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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113
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Abstract
Current strategies of regenerative medicine are focused on the restoration of pathologically altered tissue architectures by transplantation of cells in combination with supportive scaffolds and biomolecules. In recent years, considerable interest has been given to biologically active scaffolds which are based on similar analogs of the extracellular matrix that have induced synthesis of tissues and organs. To restore function or regenerate tissue, a scaffold is necessary that will act as a temporary matrix for cell proliferation and extracellular matrix deposition, with subsequent ingrowth until the tissues are totally restored or regenerated. Scaffolds have been used for tissue engineering such as bone, cartilage, ligament, skin, vascular tissues, neural tissues, and skeletal muscle and as vehicle for the controlled delivery of drugs, proteins, and DNA. Various technologies come together to construct porous scaffolds to regenerate the tissues/organs and also for controlled and targeted release of bioactive agents in tissue engineering applications. In this paper, an overview of the different types of scaffolds with their material properties is discussed. The fabrication technologies for tissue engineering scaffolds, including the basic and conventional techniques to the more recent ones, are tabulated.
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114
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Kim Y, Uhrich KE. Synthesis and Characterization of 5-Aminosalicylic Acid Based Poly(anhydride-esters) by Solution Polymerization. JOURNAL OF POLYMER SCIENCE. PART A, POLYMER CHEMISTRY 2010; 48:6003-6008. [PMID: 24431483 PMCID: PMC3889020 DOI: 10.1002/pola.24381] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Youngmi Kim
- Department of Chemistry and Chemical Biology, Rutgers University, 610 Taylor Road, Piscataway, New Jersey 08854
| | - Kathryn E Uhrich
- Department of Chemistry and Chemical Biology, Rutgers University, 610 Taylor Road, Piscataway, New Jersey 08854
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115
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Decollibus DP, Marin A, Andrianov AK. Effect of environmental factors on hydrolytic degradation of water-soluble polyphosphazene polyelectrolyte in aqueous solutions. Biomacromolecules 2010; 11:2033-8. [PMID: 20690712 DOI: 10.1021/bm100395u] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Degradation of a water-soluble polyphosphazene, poly[di(carboxylatophenoxy)phosphazene], disodium salt (PCPP) has been studied in aqueous solutions at elevated temperature. This synthetic polyelectrolyte is of interest as vaccine adjuvant and its degradability constitutes an important component of its safety and formulation stability profiles. The degradation process is manifested by a gradual reduction in the molecular weight of the polymer and cleavage of side groups, which is consistent with previously reported data on hydrolytical breakdown of water-soluble polyphosphazenes. The kinetics of hydrolytical degradation exhibits distinct pH dependence and the process is faster in solutions with lower pH. Remarkably, a number of hydrogen bond forming additives, such as polyethylene glycol and Tween displayed a dramatic accelerating effect on the degradation of PCPP, whereas inorganic salts, such as sodium chloride and potassium chloride, showed a trend for its retardation. The results can be potentially explained on the basis of acid promoted hydrolysis mechanism and macromolecular interactions in the system.
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Affiliation(s)
- Daniel P Decollibus
- Apogee Technology, Inc., 129 Morgan Drive, Norwood, Massachusetts 02062, USA
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116
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Rutherglen BG, McBath RA, Huang YL, Shipp DA. Polyanhydride Networks from Thiol−Ene Polymerizations. Macromolecules 2010. [DOI: 10.1021/ma102287v] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Broden G. Rutherglen
- Department of Chemistry and Biomolecular Science and Center for Advanced Materials Processing, Clarkson University, Potsdam, New York 13699-5810, United States
| | - Ryan A. McBath
- Department of Chemistry and Biomolecular Science and Center for Advanced Materials Processing, Clarkson University, Potsdam, New York 13699-5810, United States
| | - Yu Ling Huang
- Department of Chemistry and Biomolecular Science and Center for Advanced Materials Processing, Clarkson University, Potsdam, New York 13699-5810, United States
| | - Devon A. Shipp
- Department of Chemistry and Biomolecular Science and Center for Advanced Materials Processing, Clarkson University, Potsdam, New York 13699-5810, United States
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117
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Mallakpour S, Soltanian S, Sabzalian MR. Studies on synthesis and in vitro biodegradability of novel optically active nanostructure poly(ester-imide)s containing l-phenylalanine and l-isoleucine linkages. Colloid Polym Sci 2010. [DOI: 10.1007/s00396-010-2338-z] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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118
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Deronde BM, Carbone AL, Uhrich KE. Storage Stability Study of Salicylate-based Poly(anhydride-esters). Polym Degrad Stab 2010; 95:1778-1782. [PMID: 21152105 DOI: 10.1016/j.polymdegradstab.2010.05.008] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Storage stability was evaluated on a biodegradable salicylate-based poly(anhydride-ester) to elucidate the effects of storage conditions over time. The hydrolytically labile polymer samples were stored in powdered form at five relevant storage temperatures (-12 °C, 4 °C, 27 °C, 37 °C, 50 °C) and monitored over four weeks for changes in color, glass transition temperature, molecular weight, and extent of hydrolysis. Samples stored at lower temperatures remained relatively constant with respect to bond hydrolysis and molecular weight. Whereas, samples stored at higher temperatures displayed significant hydrolysis. For hydrolytically degradable polymers, such as these poly(anhydride-esters), samples are best stored at low temperatures under an inert atmosphere.
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Affiliation(s)
- Brittany M Deronde
- Department of Chemistry and Chemical Biology, Rutgers University, 610 Taylor Road, Piscataway, New Jersey, 08854-8087
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119
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120
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Yu NYC, Schindeler A, Little DG, Ruys AJ. Biodegradable poly(alpha-hydroxy acid) polymer scaffolds for bone tissue engineering. J Biomed Mater Res B Appl Biomater 2010; 93:285-95. [PMID: 20127987 DOI: 10.1002/jbm.b.31588] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Synthetic graft materials are emerging as a viable alternative to autogenous bone graft and bone allograft for the treatment of critical-sized bone defects. These materials can be osteoconductive but are rarely intrinsically osteogenic, although this can be greatly enhanced by the application of bone morphogenetic proteins (BMPs). This review will discuss the versatility of biodegradable poly(alpha-hydroxy acids) for the delivery of BMPs for bone tissue engineering. Poly(alpha-hydroxy acids) have a considerable potential for customization and adaptability via modification of design parameters, including scaffold architecture, composition, and biodegradability. Different fabrication techniques will also be discussed.
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Affiliation(s)
- Nicole Y C Yu
- Biomedical Engineering, School of AMME J07, University of Sydney, Sydney, Australia.
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121
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Moore JE, Soares JS, Rajagopal KR. Biodegradable Stents: Biomechanical Modeling Challenges and Opportunities. Cardiovasc Eng Technol 2010. [DOI: 10.1007/s13239-010-0005-7] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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122
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123
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Petersen LK, Sackett CK, Narasimhan B. Novel, High Throughput Method to Study in Vitro Protein Release from Polymer Nanospheres. ACTA ACUST UNITED AC 2009; 12:51-6. [DOI: 10.1021/cc900116c] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- L. K. Petersen
- Department of Chemical and Biological Engineering, Iowa State University, Ames, Iowa 50011
| | - C. K. Sackett
- Department of Chemical and Biological Engineering, Iowa State University, Ames, Iowa 50011
| | - B. Narasimhan
- Department of Chemical and Biological Engineering, Iowa State University, Ames, Iowa 50011
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124
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Manoharan C, Singh J. Evaluation of polyanhydride microspheres for basal insulin delivery: Effect of copolymer composition and zinc salt on encapsulation, in vitro release, stability, in vivo absorption and bioactivity in diabetic rats. J Pharm Sci 2009; 98:4237-50. [DOI: 10.1002/jps.21741] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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125
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Petersen LK, Xue L, Wannemuehler MJ, Rajan K, Narasimhan B. The simultaneous effect of polymer chemistry and device geometry on the in vitro activation of murine dendritic cells. Biomaterials 2009; 30:5131-42. [DOI: 10.1016/j.biomaterials.2009.05.069] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2009] [Accepted: 05/25/2009] [Indexed: 10/20/2022]
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126
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Adler AF, Petersen LK, Wilson JH, Torres MP, Thorstenson JB, Gardner SW, Mallapragada SK, Wannemuehler MJ, Narasimhan B. High throughput cell-based screening of biodegradable polyanhydride libraries. Comb Chem High Throughput Screen 2009; 12:634-45. [PMID: 19531023 DOI: 10.2174/138620709788923764] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2007] [Accepted: 01/02/2008] [Indexed: 11/22/2022]
Abstract
A parallel screening method has been developed to rapidly evaluate discrete library substrates of biomaterials using cell-based assays. The biomaterials used in these studies were surface-erodible polyanhydrides based on sebacic acid (SA), 1,6-bis(p-carboxyphenoxy)hexane (CPH), and 1,8-bis(p-carboxyphenoxy)-3,6-dioxaoctane (CPTEG) that have been previously studied as carriers for drugs, proteins, and vaccines. Linearly varying compositional libraries of 25 different polyanhydride random copolymers (based on CPH:SA and CPTEG:CPH) were designed, fabricated, and synthesized using discrete (organic solvent-resistant) multi-sample substrates created using a novel rapid prototyping method. The combinatorial libraries were characterized at high throughput using infrared microscopy and validated using 1H NMR and size exclusion chromatography. The discrete libraries were rapidly screened for biocompatibility using standard SP2/0 myeloma, CHO and L929 fibroblasts, and J774 macrophage cell lines. At a concentration of 2.8 mg/mL, there was no appreciable cytotoxic effect on any of the four cell lines evaluated by any of the CPH:SA or CPTEG:CPH compositions. Furthermore, the activation of J774 macrophages was evaluated by incubating the cells with the polyanhydride libraries and quantifying the secreted cytokines (IL-6, IL-10, IL-12, and TNFalpha). The results indicated that copolymer compositions containing at least 50% CPH induced elevated amounts of TNFalpha. In summary, the results indicated that the methodologies described herein are amenable to the high throughput analysis of synthesized biomaterials and will facilitate the rapid and rational design of materials for use in biomedical applications.
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Affiliation(s)
- Andrew F Adler
- Department of Chemical and Biological Engineering, Iowa State University, Ames, IA 50011-2230, USA
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127
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Wilson-Welder JH, Torres MP, Kipper MJ, Mallapragada SK, Wannemuehler MJ, Narasimhan B. Vaccine adjuvants: current challenges and future approaches. J Pharm Sci 2009; 98:1278-316. [PMID: 18704954 PMCID: PMC8092333 DOI: 10.1002/jps.21523] [Citation(s) in RCA: 176] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
For humans, companion animals, and food producing animals, vaccination has been touted as the most successful medical intervention for the prevention of disease in the twentieth century. However, vaccination is not without problems. With the development of new and less reactogenic vaccine antigens, which take advantage of molecular recombinant technologies, also comes the need for more effective adjuvants that will facilitate the induction of adaptive immune responses. Furthermore, current vaccine adjuvants are successful at generating humoral or antibody mediated protection but many diseases currently plaguing humans and animals, such as tuberculosis and malaria, require cell mediated immunity for adequate protection. A comprehensive discussion is presented of current vaccine adjuvants, their effects on the induction of immune responses, and vaccine adjuvants that have shown promise in recent literature.
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Affiliation(s)
- Jennifer H Wilson-Welder
- Department of Veterinary Microbiology and Preventive Medicine, Iowa State University, Ames, Iowa 50011, USA
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128
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Vert M. Degradable and bioresorbable polymers in surgery and in pharmacology: beliefs and facts. JOURNAL OF MATERIALS SCIENCE. MATERIALS IN MEDICINE 2009; 20:437-446. [PMID: 18815731 DOI: 10.1007/s10856-008-3581-4] [Citation(s) in RCA: 71] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/26/2008] [Accepted: 08/29/2008] [Indexed: 05/26/2023]
Abstract
The number of articles dealing with degradable polymers and macromolecules is increasing rapidly and the number of proposed compounds as well. However, not all have a high potential for effective applications. This contribution examines first the criteria to be taken into account when commercialisation of polymeric compounds and devices aimed at helping the body for a limited period of time, i.e. the healing time, is the main goal. What is really known is tentatively analysed by considering some of the candidates present in literature confronted to the targeted potential applications. Tentative comments are made on what should be done to qualify a candidate. Last but not least, trends in the search for polymers to be exploited in presently attracting areas such as bioresorbable stents, hydrogels to deliver bioactive macromolecules like proteins and polynucleotides or polyelectrolytes to temporarily complex charged biomacromolecules like proteins or genes are considered.
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Affiliation(s)
- Michel Vert
- Institute of Biomolecules Max Mousseron, UMR CNRS 5247, Montpellier Cedex 5, France.
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129
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Shikanov A, Vaisman B, Shikanov S, Domb AJ. Efficacy of poly(sebacic acid-co-ricinoleic acid) biodegradable delivery system for intratumoral delivery of paclitaxel. J Biomed Mater Res A 2009; 92:1283-91. [DOI: 10.1002/jbm.a.32429] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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130
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Shipp DA, McQuinn CW, Rutherglen BG, McBath RA. Elastomeric and degradable polyanhydride network polymers by step-growth thiol–ene photopolymerization. Chem Commun (Camb) 2009:6415-7. [DOI: 10.1039/b911557a] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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131
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Biocompatibility and safety evaluation of a ricinoleic acid-based poly(ester-anhydride) copolymer after implantation in rats. J Biomed Mater Res A 2009; 92:419-31. [DOI: 10.1002/jbm.a.32342] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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132
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Mallapragada SK, Narasimhan B. Immunomodulatory biomaterials. Int J Pharm 2008; 364:265-71. [DOI: 10.1016/j.ijpharm.2008.06.030] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2008] [Revised: 06/20/2008] [Accepted: 06/25/2008] [Indexed: 12/26/2022]
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133
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Jain JP, Chitkara D, Kumar N. Polyanhydrides as localized drug delivery carrier: an update. Expert Opin Drug Deliv 2008; 5:889-907. [DOI: 10.1517/17425247.5.8.889] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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134
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Falco EE, Patel M, Fisher JP. Recent Developments in Cyclic Acetal Biomaterials for Tissue Engineering Applications. Pharm Res 2008; 25:2348-56. [DOI: 10.1007/s11095-008-9620-5] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2008] [Accepted: 04/29/2008] [Indexed: 10/22/2022]
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135
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Shikanov A, Shikanov S, Vaisman B, Golenser J, Domb AJ. Paclitaxel tumor biodistribution and efficacy after intratumoral injection of a biodegradable extended release implant. Int J Pharm 2008; 358:114-20. [DOI: 10.1016/j.ijpharm.2008.02.028] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2007] [Revised: 02/13/2008] [Accepted: 02/21/2008] [Indexed: 10/22/2022]
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136
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Dong AJ, Zhang JW, Jiang K, Deng LD. Characterization and in vitro degradation of poly(octadecanoic anhydride). JOURNAL OF MATERIALS SCIENCE. MATERIALS IN MEDICINE 2008; 19:39-46. [PMID: 17577635 DOI: 10.1007/s10856-007-3166-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2006] [Accepted: 09/18/2006] [Indexed: 05/15/2023]
Abstract
Poly(octadecanoic anhydride) (POA) has been prepared by melt polycondensation of octadecanoic diacid. POA was characterized by Fourier-transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC) and wide angle X-ray diffraction (WAXD). The results of in vitro degradation and SEM micrographs show that the erosion process of POA is neither bulk nor perfect surface erosion but rather has elements of both in phosphate buffer at 37 degrees C. The moving erosion front is characteristic of surface erosion whereas the remaining porous shell stems from bulk erosion. While a significant special degradation property of POA is that POA presents a very slow degradation rate in acidic condition (pH 5.98), only 1.64% weight loss for 20 days, and it completely degrades after 18 days in basic buffer (pH 7.4). Comparing with poly(sebacic anhydride) (PSA), POA has the higher crystallization degree, and the slower hydrolytic rate.
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Affiliation(s)
- An-Jie Dong
- Department of Polymer Science and Technology, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China
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137
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Qian H, Mathiowitz E. (Trimethylsilyl)ethoxyacetylene as a Dehydrating Agent for Polyanhydride Synthesis. Macromolecules 2007. [DOI: 10.1021/ma071188a] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Haitao Qian
- Department of Molecular Pharmacology, Physiology and Biotechnology, Brown University, 171 Meeting St., Providence, Rhode Island 02912
| | - Edith Mathiowitz
- Department of Molecular Pharmacology, Physiology and Biotechnology, Brown University, 171 Meeting St., Providence, Rhode Island 02912
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138
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139
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Abstract
Bone and ligament injuries present the greatest challenges in connective tissue regeneration. The design of materials for these applications lies at the forefront of material science and is the epitome of its current ambition. Indeed, its goal is to design and fabricate reproducible, bioactive and bioresorbable 3D scaffolds with tailored properties that are able to maintain their structure and integrity for predictable times, even under load-bearing conditions. Unfortunately, the mechanical properties of today's available porous scaffolds fall short of those exhibited by complex human tissues, such as bone and ligament. The manipulation of structural parameters in the design of scaffolds and their bioactivation, through the incorporation of soluble and insoluble signals capable of promoting cell activities, are discussed as possible strategies to improve the formation of new tissues both in vitro and in vivo. This review focuses on the different approaches adopted to develop bioactive composite systems for use as temporary scaffolds for bone and anterior ligament regeneration.
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Affiliation(s)
- Vincenzo Guarino
- Institute of Composite and Biomedical Materials (IMCB-CNR), Piazzale Tecchio 80, 80125 Naples, Italy.
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140
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Abstract
To tailor the erosion rate of polyanhydrides while retaining their surface erosion characteristics, new three-component polyanhydrides of sebacic acid, 1,3-bis(p-carboxyphenoxy)propane and poly(ethylene glycol) were synthesized. The hydrophilicity of the polymer increased and its mechanical strength decreased with increasing PEG content. Correspondingly, the erosion rate increases with increasing PEG content, whereas it decreases with increasing specimen thickness. This indicates that the incorporation of poly(ethylene glycol) into traditional two-component polyanhydrides retains their surface erosion properties while making the erosion rate tunable. The new polyanhydrides hold potential for drug delivery applications.
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Affiliation(s)
- Sijian Hou
- Department of Biologic and Materials Sciences, University of Michigan, Ann Arbor, MI 48109, USA
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141
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Pulkkinen M, Malin M, Tarvainen T, Saarimäki T, Seppälä J, Järvinen K. Effects of block length on the enzymatic degradation and erosion of oxazoline linked poly-epsilon-caprolactone. Eur J Pharm Sci 2007; 31:119-28. [PMID: 17433634 DOI: 10.1016/j.ejps.2007.03.001] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2006] [Revised: 01/22/2007] [Accepted: 03/01/2007] [Indexed: 11/25/2022]
Abstract
The aim of the study was to develop enzyme sensitive polymers for pharmaceutical applications. Thus, 2,2'-bis(2-oxazoline)-linked poly-epsilon-caprolactone (PCL-O) polymers were synthesized by using epsilon-caprolactone precursors with different molecular weights (M(n): 1500, 3900, 7500 and 12,000g/mol), and the effects of PCL block length on enzymatic degradation and erosion (weight loss) of PCL-O films were studied. Solvent cast PCL and PCL-O films were incubated (22 days) in the presence of pancreatin (1%, pH 7.5), with and without enzyme inhibitors. In the absence of enzyme inhibitors, surface erosion of the PCL-O films occurred during incubation, and the erosion of the PCL-O films increased in parallel with a decrease in the PCL block length. The presence of the lipase inhibitors, paraoxon-ethyl and tetrahydrolipstatin delayed the weight loss of the PCL-O films. These results indicate that lipase was mainly responsible for the enzymatic erosion of the PCL-O films. In comparison, practically no weight loss of the PCL or the PCL-O films was observed in phosphate buffer (pH 7.4) (28 days incubation). The results demonstrate that the studied epsilon-caprolactone based poly(ester-amide)s are enzyme sensitive polymers whose erosion rate can be controlled by the PCL block length.
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Affiliation(s)
- Mika Pulkkinen
- Department of Pharmaceutics, University of Kuopio, P.O. Box 1627, FIN-70211 Kuopio, Finland.
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142
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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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143
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Shikanov A, Domb AJ, Weiniger CF. Long acting local anesthetic–polymer formulation to prolong the effect of analgesia. J Control Release 2007; 117:97-103. [PMID: 17137669 DOI: 10.1016/j.jconrel.2006.10.014] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2006] [Revised: 09/06/2006] [Accepted: 10/05/2006] [Indexed: 11/15/2022]
Abstract
Prolonged postoperative analgesia cannot be achieved using single injections of local anesthetic solutions. The study objective was to evaluate the efficacy and toxicity of a new formulation of bupivacaine loaded in an injectable fatty acid based biodegradable polymer poly(sebacic-co-ricinoleic acid) for producing motor and sensory block when injected near the sciatic nerve. Bupivacaine was dissolved in poly(fatty ester-anhydride) paste and tested for drug release in vitro and in vivo after injection in mice. The efficacy and toxicity of the polymer-drug combination was determined by injecting the polymer formulation near the sciatic nerve of mice and measure the sensory and motor nerve blockade for 48 h, while monitoring the animal general health and the injection site. Seventy percent of the incorporated drug was released during 1 week in vitro. Single injection of 10% bupivacaine in the polymer caused motor and sensory block that lasted 30 h. Microscopic examination of the injection sites revealed only mild infiltration in three of eight examined tissues with no pathological findings for internal organs were found. In conclusion the polymer poly(sebacic-co-ricinoleic acid) is a safe carrier for prolonged activity of bupivacaine.
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Affiliation(s)
- Ariella Shikanov
- School of Pharmacy, Hadassah Hebrew University Medical Schools, Ein Kerem, Jerusalem, POB 12000, Israel
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144
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Soares JS, Moore JE, Rajagopal KR. Theoretical Modeling of Cyclically Loaded, Biodegradable Cylinders. MODELING OF BIOLOGICAL MATERIALS 2007. [DOI: 10.1007/978-0-8176-4411-6_4] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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145
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Hiremath JG, Kusum Devi V, Devi K, Domb AJ. Biodegradable poly(sebacic acid-co-ricinoleic-ester anhydride) tamoxifen citrate implants: Preparation andin vitro characterization. J Appl Polym Sci 2007. [DOI: 10.1002/app.27391] [Citation(s) in RCA: 16] [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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146
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Chemo-enzymatic synthesis of optically active polymeric prodrug of naproxen, ketoprofen and ibuprofen. POLYMER 2006. [DOI: 10.1016/j.polymer.2006.06.043] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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147
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Kipper MJ, Wilson JH, Wannemuehler MJ, Narasimhan B. Single dose vaccine based on biodegradable polyanhydride microspheres can modulate immune response mechanism. J Biomed Mater Res A 2006; 76:798-810. [PMID: 16345084 DOI: 10.1002/jbm.a.30545] [Citation(s) in RCA: 89] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
This study focuses on the development of single dose vaccines based on biodegradable polyanhydride microspheres that have the unique capability to modulate the immune response mechanism. The polymer system employed consists of copolymers of 1,6-bis(p-carboxyphenoxy)hexane and sebacic acid. Two copolymer formulations that have been shown to provide extended release kinetics and protein stability were investigated. Using tetanus toxoid (TT) as a model antigen, in vivo studies in C3H/HeOuJ mice demonstrated that the encapsulation procedure preserves the immunogenicity of the TT. The polymer itself exhibited an adjuvant effect, enhancing the immune response to a small dose of TT. The microspheres provided a prolonged exposure to TT sufficient to induce both a primary and a secondary immune response (i.e., high antibody titers) with high-avidity antibody production, without requiring an additional administration. Antigen-specific proliferation 28 weeks after a single immunization indicated that immunization with the polyanhydride microspheres generated long-lived memory cells and plasma cells (antibody-secreting B cells) that generally do not occur without maturation signals from T helper cells. Furthermore, by altering the vaccine formulation, the overall strength of the T helper type 2 immune response was selectively diminished, resulting in a balanced immune response, without reducing the overall titer. This result is striking, considering free TT induces a T helper type 2 immune response, and has important implications for developing vaccines to intracellular pathogens. The ability to selectively tune the immune response without the administration of additional cytokines or noxious adjuvants is a unique feature of this delivery vehicle that may make it an excellent candidate for vaccine development.
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Affiliation(s)
- Matt J Kipper
- Department of Chemical and Biological Engineering, Iowa State University, 2035 Sweeney Hall, Ames, 50011-2230, USA
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148
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Torres MP, Vogel BM, Narasimhan B, Mallapragada SK. Synthesis and characterization of novel polyanhydrides with tailored erosion mechanisms. J Biomed Mater Res A 2006; 76:102-10. [PMID: 16138330 DOI: 10.1002/jbm.a.30510] [Citation(s) in RCA: 92] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
We have designed a new synthesis route to create polyanhydrides based on monomers that contain hydrophilic entities within highly hydrophobic backbones. The method results in polyanhydrides that can be easily processed into drug-containing tablets. The synthesis, characterization, and erosion studies of polyanhydride copolymers based on 1,6-bis(p-carboxyphenoxy)hexane (CPH), which is highly hydrophobic, and 1,8-bis(p-carboxyphenoxy)-3,6-dioxaoctane (CPTEG), which has hydrophilic oligomeric ethylene glycol segments in the monomer unit, was performed using a combination of molecular spectroscopy, thermal analysis, gravimetry, and scanning electron microscopy. The studies demonstrate that by increasing the CPH content in the CPTEG:CPH copolymers, the erosion of the system can be tailored from bulk-eroding to surface-eroding mechanism. These systems have promise as protein carriers.
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Affiliation(s)
- María P Torres
- Department of Chemical and Biological Engineering, Iowa State University, Ames, Iowa 50011, USA
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149
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Andjelić S, Yuan J, Jamiolkowski DD, Diluccio R, Bezwada R, Zhang H, Mijović J. Hydrophilic Absorbable Copolyester Exhibiting Zero-Order Drug Release. Pharm Res 2006; 23:821-34. [PMID: 16463009 DOI: 10.1007/s11095-006-9664-3] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2005] [Accepted: 12/06/2005] [Indexed: 10/25/2022]
Abstract
PURPOSE A novel absorbable hydrophilic copolyester developed in our laboratory, amorphous 40/60 poly(ethylene diglycolate-co-glycolide), exhibits outstanding physical properties. Films made from this material appear fully transparent, colorless, soft and slightly elastic, but relatively strong and durable materials so that they can be potentially used as stand-alone devices in various in-vivo medical applications. In this study, in-vitro drug release characteristics of this copolyester were examined. METHODS High Performance Liquid Chromatography was used to generate release profiles on selected non-steroidal anti-inflammatory agents, NSAIDs. In addition, dielectric relaxation spectroscopy, as well as mid- and near infrared spectroscopy, were used to study specific polymer chain interactions in water and buffer solution as a function of aging time at 37 degrees C. RESULTS This copolyester, compression molded into a film, exhibited nearly constant in-vitro release of various hydrophilic and hydrophobic drugs. The release profile showed minimal or, in most cases, no burst effect. The effect was observed with the three NSAIDs that were tested as model compounds; however, this system may prove generally useful for other drug entities. In-vitro hydrolysis conducted at 37 degrees C on this hydrophilic copolyester revealed an unusually long induction period (no hydrolysis for up to 6 days), followed by the relatively rapid hydrolysis. Data from dipole relaxation spectroscopy indicated that the water molecules do not structurally associate with the polymer chains in phosphate buffer during initial hydrolysis period. CONCLUSIONS The results suggest unique dynamics of water diffusion through the polymer matrix that may play a critical role in achieving controlled release properties. Furthermore, we suspect that the molecular interactions associated with this new synthetic absorbable material may find a critical utility in important medical applications.
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Affiliation(s)
- Sasa Andjelić
- Procedural Implants R&D, Ethicon, a Johnson & Johnson Company, Route 22 West, Somerville, New Jersey 08876-0151, USA.
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150
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Gunatillake P, Mayadunne R, Adhikari R. Recent developments in biodegradable synthetic polymers. BIOTECHNOLOGY ANNUAL REVIEW 2006; 12:301-47. [PMID: 17045198 DOI: 10.1016/s1387-2656(06)12009-8] [Citation(s) in RCA: 181] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/02/2022]
Abstract
This chapter reviews recent developments in biodegradable synthetic polymers focusing on tailoring polymer structures to meet material specification for emerging applications such as tissue engineered products and therapies. Major classes and new families of synthetic polymers are discussed with regard to synthesis, properties and biodegradability, and known degradation modes and products are summarized based on studies reported during the past 10-15 years. Polyesters and their copolymers, polyurethanes, polyphosphazenes, polyanhydrides, polycarbonates, polyesteramides and recently developed injectable polymer systems based on polypropylenefumarates, polyurethanes and acrylate/urethane systems are reviewed. Polyesters such as polyglycolides, polylactides and their copolymers still remain as the major class of synthetic biodegradable polymers with products in clinical use. Although various copolymerization methods have addressed needs of different applications, release of acidic degradation products, processing difficulties and limited range of mechanical properties remains as major disadvantages of this family of polymers. Injectable polymers based on urethane and urethane/acrylate have shown great promise in developing delivery systems for tissue engineered products and therapies.
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Affiliation(s)
- Pathiraja Gunatillake
- PolyNovo Biomaterials Pty Ltd, Bag 10, Clayton South, Bayview Avenue, Clayton 3169, Australia.
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