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Sirisinha K, Wirasate S, Sirisinha C, Wattanakrai N. One-Pot Reactive Melt Recycling of PLA Post-Consumer Waste for the Production of Block Copolymer Nanocomposites of High Strength and Ductility. Polymers (Basel) 2022; 14:polym14173642. [PMID: 36080715 PMCID: PMC9459722 DOI: 10.3390/polym14173642] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2022] [Revised: 08/26/2022] [Accepted: 08/30/2022] [Indexed: 12/23/2022] Open
Abstract
Post-consumer waste recycling is a crucial issue for building a sustainable society. However, mechanical recycling of poly(lactic acid) (PLA) often reduces the performance of the recycled material because PLA has a strong tendency to degrade during reprocessing. Therefore, it is of great interest to develop an effective recycling method to improve the mechanical performance of this material. This paper presents a one-pot melt process for turning PLA waste into a biodegradable block copolymer and its high strength and ductility composite. The process was conducted in a melt-mixer through a transesterification of PLA with poly(ethylene glycol) (PEG) or poly(propylene glycol) (PPG) as a soft component and clay as reinforcement. Effects of soft component content and sequence of clay addition on the mechanical performance of the prepared materials were focused. The results showed the successful preparation of PLA-based multiblock copolymers of high molecular weights (~100 kDa). Both virgin PLA and recycled source could serve as the starting material. PEG was more efficient than PPG in providing an intense improvement of PLA ductility. The nanocomposite of intercalated structure yielded nearly 100 times higher elongation at break (Eb = 506%) than the starting PLA (Eb = 5.6%) with high strength of 39.5 MPa and modulus of 1.4 GPa, considering the advantages of clay addition. Furthermore, the products with a broadened range of properties can be designed based on the ratio of PLA and soft component, as well as the organization and spatial distribution of clay in the copolymer matrices.
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Affiliation(s)
- Kalyanee Sirisinha
- Department of Chemistry, Faculty of Science, Mahidol University, Bangkok 10400, Thailand
- Correspondence:
| | - Supa Wirasate
- Department of Chemistry, Faculty of Science, Mahidol University, Bangkok 10400, Thailand
| | - Chakrit Sirisinha
- Rubber Technology Research Centre (RTEC), Faculty of Science, Mahidol University, Nakhon Prathom 73170, Thailand
| | - Noppasorn Wattanakrai
- Department of Chemistry, Faculty of Science, Mahidol University, Bangkok 10400, Thailand
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Guo S, Shi Y, Liang Y, Liu L, Sun K, Li Y. Relationship and improvement strategies between drug nanocarrier characteristics and hemocompatibility: What can we learn from the literature. Asian J Pharm Sci 2021; 16:551-576. [PMID: 34849162 PMCID: PMC8609445 DOI: 10.1016/j.ajps.2020.12.002] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2020] [Revised: 12/01/2020] [Accepted: 12/21/2020] [Indexed: 01/30/2023] Open
Abstract
This article discusses the various blood interactions that may occur with various types of nano drug-loading systems. Nanoparticles enter the blood circulation as foreign objects. On the one hand, they may cause a series of inflammatory reactions and immune reactions, resulting in the rapid elimination of immune cells and the reticuloendothelial system, affecting their durability in the blood circulation. On the other hand, the premise of the drug-carrying system to play a therapeutic role depends on whether they cause coagulation and platelet activation, the absence of hemolysis and the elimination of immune cells. For different forms of nano drug-carrying systems, we can find the characteristics, elements and coping strategies of adverse blood reactions that we can find in previous researches. These adverse reactions may include destruction of blood cells, abnormal coagulation system, abnormal effects of plasma proteins, abnormal blood cell behavior, adverse immune and inflammatory reactions, and excessive vascular stimulation. In order to provide help for future research and formulation work on the blood compatibility of nano drug carriers.
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Affiliation(s)
- Shiqi Guo
- School of Pharmacy, Key Laboratory of Molecular Pharmacology and Drug Evaluation (Yantai University), Ministry of Education, Collaborative Innovation Center of Advanced Drug Delivery System and Biotech Drugs in Universities of Shandong, Yantai University, Yantai 264005, China
| | - Yanan Shi
- College of Life Science, Yantai University, Yantai 264005, China
| | - Yanzi Liang
- School of Pharmacy, Key Laboratory of Molecular Pharmacology and Drug Evaluation (Yantai University), Ministry of Education, Collaborative Innovation Center of Advanced Drug Delivery System and Biotech Drugs in Universities of Shandong, Yantai University, Yantai 264005, China
| | - Lanze Liu
- College of Life Science, Yantai University, Yantai 264005, China
| | - Kaoxiang Sun
- School of Pharmacy, Key Laboratory of Molecular Pharmacology and Drug Evaluation (Yantai University), Ministry of Education, Collaborative Innovation Center of Advanced Drug Delivery System and Biotech Drugs in Universities of Shandong, Yantai University, Yantai 264005, China
- State Key Laboratory of Long-acting and Targeting Drug Delivery System, Luye Pharmaceutical Co., Ltd., Yantai 264003, China
| | - Youxin Li
- School of Pharmacy, Key Laboratory of Molecular Pharmacology and Drug Evaluation (Yantai University), Ministry of Education, Collaborative Innovation Center of Advanced Drug Delivery System and Biotech Drugs in Universities of Shandong, Yantai University, Yantai 264005, China
- State Key Laboratory of Long-acting and Targeting Drug Delivery System, Luye Pharmaceutical Co., Ltd., Yantai 264003, China
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Zebiri H, Van Den Berghe H, Sayegh S, Chammas PE, Pompée C, Chammas M, Garric X. Synthesis of PLA-poly(ether urethane)-PLA copolymers and design of biodegradable anti-adhesive membranes for orthopaedic applications. J Mater Chem B 2021; 9:832-845. [PMID: 33347521 DOI: 10.1039/d0tb02545c] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Peritendinous adhesions cause chronic pain and disability. Leading causes are trauma to tendons and surrounding tissues and immobilization after surgery. Adhesions occur between 24 hours to 6 weeks after surgery. Anti-adhesion barriers are currently the best option available to prevent peritendinous adhesions, but are ineffective and difficult to use. We developed an anti-adhesive membrane that can be easily applied during tendon surgery and effectively prevent adhesions. The membrane is based on a new triblock copolymer, is non-toxic, can be bio-eliminated, and has a degradation rate of more than 6 weeks for optimal anti-adhesion effect. We synthesized and characterized poly(ether urethane) (PEU) from poly(ethylene glycol). Triblock copolymers poly(lactic acid)-PEU-poly(lactic acid) (PLA-PEU-PLA) were then synthesized from PEU with PLA blocks of different lengths, and characterized. The membranes were shaped by hot molding and their mechanical properties, contact angle, water uptake, the kinetics of in vitro degradation and cytotoxicity were studied. Mechanical properties were developed according to the needs of orthopaedic surgeons. Results showed that membranes maintained their filmogenic integrity, have a degradation rate for optimal adhesion prevention, can be bioeliminated and biocompatible suggesting that they could be safely and effectively used as anti-adhesion orthopaedic devices. These results support the use of PLA-PEU-PLA membranes as a medical device, however, the effectiveness of the membranes in vivo needs to be further evaluated. A future study using an in vivo rat model of postoperative peritendinous adhesions is currently being developed.
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Affiliation(s)
- Hadda Zebiri
- Institut des Biomolécules Max Mousseron (IBMM), UMR 5247, CNRS, Université Montpellier, ENSCM, Faculté de Pharmacie, Bâtiment I, 15 Avenue Charles Flahault, BP14491, 34093 Montpellier Cedex 5, France.
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Sharma D, Singh J. Long-term glycemic control and prevention of diabetes complications in vivo using oleic acid-grafted-chitosan‑zinc-insulin complexes incorporated in thermosensitive copolymer. J Control Release 2020; 323:161-178. [PMID: 32283211 PMCID: PMC7299807 DOI: 10.1016/j.jconrel.2020.04.012] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2020] [Revised: 03/12/2020] [Accepted: 04/07/2020] [Indexed: 12/31/2022]
Abstract
Daily injections for basal insulin therapy are far from ideal resulting in hypo/hyperglycemic episodes associated with fatal complications in type-1 diabetes patients. Here we report a delivery system that provides controlled release of insulin closely mimicking physiological basal insulin requirement for an extended period following a single subcutaneous injection. Stability of insulin was significantly improved by formation of zinc-insulin hexamers, further stabilized by electrostatic complex formation with chitosan polymer. Insulin complexes were homogenously incorporated into PLA-PEG-PLA, a biodegradable thermogel copolymer, that instantaneously forms a subcutaneous gel-depot following injection. Chitosan polymer was hydrophobically modified using oleic acid prior to complex formation with insulin to enable distribution of oleic acid-grafted-chitosan‑zinc-insulin complexes into the hydrophobic core of PLA-PEG-PLA thermogel-copolymer micelles. In vivo, daily administration of marketed long-acting insulin, glargine, resulted in fluctuating blood glucose levels between 91 and 443 mg/dL in type 1 diabetic rats. However, single administration of thermogel copolymeric formulation successfully demonstrated slow diffusion of insulin complexes maintaining peak-free basal insulin level of 21 mU/L for 91 days. Sustained release of basal insulin also correlated with efficient glycemic control (blood glucose <120 mg/dL), prevention of diabetic ketoacidosis and absence of cataract development, unlike other treatment groups. Moreover, there was no sign of inflammation, tissue damage, or collagen deposition around depot site, suggesting exceptional biocompatibility of the formulation for long-term use.
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Affiliation(s)
- Divya Sharma
- Department of Pharmaceutical Sciences, School of Pharmacy, College of Health Professions, North Dakota State University, Fargo 58105, ND, USA.
| | - Jagdish Singh
- Deparment of Pharmaceutical Sciences, North Dakota State University, USA.
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Sharma D, Arora S, Singh J. Smart Thermosensitive Copolymer Incorporating Chitosan-Zinc-Insulin Electrostatic Complexes for Controlled Delivery of Insulin: Effect of Chitosan Chain Length. INT J POLYM MATER PO 2019; 69:1054-1068. [PMID: 33012880 DOI: 10.1080/00914037.2019.1655750] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
This work was designed to optimize thermosensitive copolymeric depot-based system for delivering insulin at a controlled rate for a prolonged period following a single subcutaneous injection. Intrinsic ability of insulin to form hexamers in the presence of zinc and electrostatic complexes with chitosan (CS) were explored for improving stability and release characteristics of insulin through the copolymeric depot. CS-zinc-insulin complexes were prepared using CS of different chain lengths (5, 30, 50, 200 kDa). Effect of different chain lengths of CS on the thermal stability, binding constant, and release profile of insulin was determined. Increasing chain length of CS demonstrated increasing thermal stability of insulin. However, higher chain length of CS adversely affected the release profile of insulin. Hydrolytic degradation analysis showed rapid degradation of copolymer in formulation containing higher chain length of CS (200 kDa)-zinc-insulin complexes, implying formation of bigger pores and channels in copolymeric matrix during initial release in this system. However, formulation containing smaller chain length of CS (5 kDa)-zinc-insulin complexes demonstrated slow copolymer degradation and sustained insulin release profile. Additionally, CS-zinc-insulin complexes were effective in preserving stability of insulin during the entire duration of release and storage.
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Affiliation(s)
- Divya Sharma
- Department of Pharmaceutical Sciences, School of Pharmacy, College of Health Professions, North Dakota State University, Fargo 58105, ND, USA
| | - Sanjay Arora
- Department of Pharmaceutical Sciences, School of Pharmacy, College of Health Professions, North Dakota State University, Fargo 58105, ND, USA
| | - Jagdish Singh
- Department of Pharmaceutical Sciences, School of Pharmacy, College of Health Professions, North Dakota State University, Fargo 58105, ND, USA
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Francolini I, Silvestro I, Di Lisio V, Martinelli A, Piozzi A. Synthesis, Characterization, and Bacterial Fouling-Resistance Properties of Polyethylene Glycol-Grafted Polyurethane Elastomers. Int J Mol Sci 2019; 20:E1001. [PMID: 30823606 PMCID: PMC6412681 DOI: 10.3390/ijms20041001] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2019] [Revised: 02/15/2019] [Accepted: 02/20/2019] [Indexed: 12/13/2022] Open
Abstract
Despite advances in material sciences and clinical procedures for surgical hygiene, medical device implantation still exposes patients to the risk of developing local or systemic infections. The development of efficacious antimicrobial/antifouling materials may help with addressing such an issue. In this framework, polyethylene glycol (PEG)-grafted segmented polyurethanes were synthesized, physico-chemically characterized, and evaluated with respect to their bacterial fouling-resistance properties. PEG grafting significantly altered the polymer bulk and surface properties. Specifically, the PEG-grafted polyurethanes possessed a more pronounced hard/soft phase segregated microstructure, which contributed to improving the mechanical resistance of the polymers. The better flexibility of the soft phase in the PEG-functionalized polyurethanes compared to the pristine polyurethane (PU) was presumably also responsible for the higher ability of the polymer to uptake water. Additionally, dynamic contact angle measurements evidenced phenomena of surface reorganization of the PEG-functionalized polyurethanes, presumably involving the exposition of the polar PEG chains towards water. As a consequence, Staphylococcus epidermidis initial adhesion onto the surface of the PEG-functionalized PU was essentially inhibited. That was not true for the pristine PU. Biofilm formation was also strongly reduced.
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Affiliation(s)
- Iolanda Francolini
- Department of Chemistry, Sapienza University of Rome, 00185 Rome, Italy.
| | - Ilaria Silvestro
- Department of Chemistry, Sapienza University of Rome, 00185 Rome, Italy.
| | - Valerio Di Lisio
- Department of Chemistry, Sapienza University of Rome, 00185 Rome, Italy.
| | - Andrea Martinelli
- Department of Chemistry, Sapienza University of Rome, 00185 Rome, Italy.
| | - Antonella Piozzi
- Department of Chemistry, Sapienza University of Rome, 00185 Rome, Italy.
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Facile melt processing technique for the preparation of super ductile PLA–PEG multiblock copolymers: The roles of catalyst and antioxidant loadings. Polym Degrad Stab 2018. [DOI: 10.1016/j.polymdegradstab.2018.10.010] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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Drug-Polymer Interaction, Pharmacokinetics and Antitumor Effect of PEG-PLA/Taxane Derivative TM-2 Micelles for Intravenous Drug Delivery. Pharm Res 2018; 35:208. [PMID: 30215146 DOI: 10.1007/s11095-018-2477-3] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2018] [Accepted: 08/07/2018] [Indexed: 10/28/2022]
Abstract
PURPOSE A novel polymer micelle was prepared with a high drug loading, good stability, high tolerance and better anti-tumor effect. METHODS TM-2 was encapsulated in poly-block-poly (D, L-lactic acid) self-assembled micelles by the thin-film hydration method. From the critical micelle concentrations of the copolymers, particle size, drug loading and encapsulation efficiency of drug-loading micelles, the appropriate polymer material could be assessed. Comparisons between TM-2 solution and TM-2 micelles were done to evaluate the pharmacokinetics and toxicity in rats, compared with Taxol to evaluate the anti-tumor effect in mice. RESULTS The optimized TM-2 micelles achieved a high drug loading (~20%) with the polymer material of PEG2k-PLA2.5k, with a particle size of 30 nm and no significant change in particle size after lyophilization. The result of pharmacokinetic experiment displayed that the half-life in vivo was obviously prolonged. The maximum tolerated dose of TM-2 micelles was approximately 25 mg/kg in rats, and the relative tumor growth rate of Taxol (15 mg/kg), TM-2 (10 mg/kg), TM-2 (15 mg/kg) and TM-2 (40 mg/kg) in mice were 49.35%, 49.14%, 36.44 and 9.98% respectively. CONCLUSIONS TM-2 micelles with high drug loading increased drug solubility, improved tolerance, antitumor effects and reduced toxicity.
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Špírková M, Hodan J, Serkis-Rodzeń M, Kredatusová J, Zhigunov A, Kotek J. The effect of pre-set extension on the degree of hydrolytic degradation in multicomponent polyurethane elastomers. Polym Degrad Stab 2017. [DOI: 10.1016/j.polymdegradstab.2017.05.033] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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10
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The influence of the length of the degradable segment on the functional properties and hydrolytic stability of multi-component polyurethane elastomeric films. Polym Degrad Stab 2017. [DOI: 10.1016/j.polymdegradstab.2017.01.021] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Kucharczyk P, Pavelková A, Stloukal P, Sedlarík V. Degradation behaviour of PLA-based polyesterurethanes under abiotic and biotic environments. Polym Degrad Stab 2016. [DOI: 10.1016/j.polymdegradstab.2016.04.019] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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12
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Li L, Liu X, Niu Y, Ye J, Huang S, Liu C, Xu K. Synthesis and wound healing of alternating block polyurethanes based on poly(lactic acid) (PLA) and poly(ethylene glycol) (PEG). J Biomed Mater Res B Appl Biomater 2016; 105:1200-1209. [DOI: 10.1002/jbm.b.33670] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2015] [Revised: 01/21/2016] [Accepted: 03/10/2016] [Indexed: 11/06/2022]
Affiliation(s)
- Linjing Li
- Multidisciplinary Research Center, Shantou University; Shantou Guangdong 515063 China
| | - Xiangyu Liu
- Multidisciplinary Research Center, Shantou University; Shantou Guangdong 515063 China
| | - Yuqing Niu
- Multidisciplinary Research Center, Shantou University; Shantou Guangdong 515063 China
| | - Jianfu Ye
- Multidisciplinary Research Center, Shantou University; Shantou Guangdong 515063 China
| | - Shuiwen Huang
- Multidisciplinary Research Center, Shantou University; Shantou Guangdong 515063 China
| | - Chao Liu
- Aleo BME, Inc; University Park Pennsylvania 16802
| | - Kaitian Xu
- Multidisciplinary Research Center, Shantou University; Shantou Guangdong 515063 China
- Department of Materials Science and Engineering; Jinan University; Guangzhou 510632 China
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13
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Preparation and properties of biodegradable polyurethane networks from carbonated soybean oil. Polym Bull (Berl) 2015. [DOI: 10.1007/s00289-015-1342-3] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Barrett DG, Luo W, Yousaf MN. Developing chemoselective and biodegradable polyester elastomers for bioscaffold application. J Mater Chem B 2015; 3:1405-1414. [PMID: 32264491 DOI: 10.1039/c4tb01481b] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Thermal polyesterification has emerged as a successful method for synthesizing polyesters for biomedical applications. However, to date, no general functionalization strategy has been incorporated into materials designed by the thermal polycondensation of polyacids and polyols. Herein, we report the design of several elastomers based on the thermal polycondensation of 4-ketopimelic acid, citric acid, and one of two diols: 1,6-hexanediol or 1,4-cyclohexanedimethanol. By varying the diol and the curing conditions, several elastomers were designed with a range of physical and mechanical properties. Poly(diol 4-ketopimelate-co-diol citrate) achieved Young's modulus, ultimate tensile stress, and rupture strain values of 0.39-1.13 MPa, 0.27-1.04 MPa, and 108-426%, respectively. Additionally, the incorporation of the ketone from 4-ketopimelic acid gave these materials two advantageous characteristics: a site for covalent functionalization through oxime formation and the ability to covalently bond to the surrounding tissue through imine linkages. Biocompatibility was studied both in vitro and in vivo in order to gain a complete understanding as to how biological systems respond to these novel materials. Based on preliminary results, we believe that poly(diol 4-ketopimelate-co-diol citrate) polyketoesters are excellent candidates for biomaterials.
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Affiliation(s)
- Devin G Barrett
- Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA.
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Niu Y, Li L, Chen KC, Chen F, Liu X, Ye J, Li W, Xu K. Scaffolds from alternating block polyurethanes of poly(ɛ-caprolactone) and poly(ethylene glycol) with stimulation and guidance of nerve growth and better nerve repair than autograft. J Biomed Mater Res A 2014; 103:2355-64. [DOI: 10.1002/jbm.a.35372] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2014] [Accepted: 11/16/2014] [Indexed: 11/12/2022]
Affiliation(s)
- Yuqing Niu
- Multidisciplinary Research Center, Shantou University; Daxue Lu 243 Shantou Guangdong 515063 China
| | - Linjing Li
- Multidisciplinary Research Center, Shantou University; Daxue Lu 243 Shantou Guangdong 515063 China
| | - Kevin C. Chen
- Multidisciplinary Research Center, Shantou University; Daxue Lu 243 Shantou Guangdong 515063 China
| | - Feiran Chen
- Department of Chemistry; Jinan University; Guangzhou 510632 China
| | - Xiangyu Liu
- Multidisciplinary Research Center, Shantou University; Daxue Lu 243 Shantou Guangdong 515063 China
| | - Jianfu Ye
- Multidisciplinary Research Center, Shantou University; Daxue Lu 243 Shantou Guangdong 515063 China
| | - Wei Li
- Department of Neurosurgery; the First Affiliated Hospital, Jinan University; Guangzhou 510630 China
| | - Kaitian Xu
- Department of Materials Science and Engineering; Jinan University; Guangzhou 510632 China
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