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Nakhaei K, Ishijima M, Ikeda T, Ghassemi A, Saruta J, Ogawa T. Ultraviolet Light Treatment of Titanium Enhances Attachment, Adhesion, and Retention of Human Oral Epithelial Cells via Decarbonization. MATERIALS (BASEL, SWITZERLAND) 2020; 14:E151. [PMID: 33396339 PMCID: PMC7796045 DOI: 10.3390/ma14010151] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/04/2020] [Revised: 12/22/2020] [Accepted: 12/28/2020] [Indexed: 01/01/2023]
Abstract
Early establishment of soft-tissue adhesion and seal at the transmucosal and transcutaneous surface of implants is crucial to prevent infection and ensure the long-term stability and function of implants. Herein, we tested the hypothesis that treatment of titanium with ultraviolet (UV) light would enhance its interaction with epithelial cells. X-ray spectroscopy showed that UV treatment significantly reduced the atomic percentage of surface carbon on titanium from 46.1% to 28.6%. Peak fitting analysis revealed that, among the known adventitious carbon contaminants, C-C and C=O groups were significantly reduced after UV treatment, while other groups were increased or unchanged in percentage. UV-treated titanium attracted higher numbers of human epithelial cells than untreated titanium and allowed more rapid cell spread. Hemi-desmosome-related molecules, integrin β4 and laminin-5, were upregulated at the gene and protein levels in the cells on UV-treated surfaces. The result of the detachment test revealed twice as many cells remaining adherent on UV-treated than untreated titanium. The enhanced cellular affinity of UV-treated titanium was equivalent to laminin-5 coating of titanium. These data indicated that UV treatment of titanium enhanced the attachment, adhesion, and retention of human epithelial cells associated with disproportional removal of adventitious carbon contamination, providing a new strategy to improve soft-tissue integration with implant devices.
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Affiliation(s)
- Kourosh Nakhaei
- Weintraub Center for Reconstructive Biotechnology, Division of Advanced Prosthodontics, UCLA School of Dentistry, Los Angeles, CA 90095, USA; (K.N.); (M.I.); (T.I.); (A.G.); (T.O.)
| | - Manabu Ishijima
- Weintraub Center for Reconstructive Biotechnology, Division of Advanced Prosthodontics, UCLA School of Dentistry, Los Angeles, CA 90095, USA; (K.N.); (M.I.); (T.I.); (A.G.); (T.O.)
| | - Takayuki Ikeda
- Weintraub Center for Reconstructive Biotechnology, Division of Advanced Prosthodontics, UCLA School of Dentistry, Los Angeles, CA 90095, USA; (K.N.); (M.I.); (T.I.); (A.G.); (T.O.)
- Department of Complete Denture Prosthodontics, Nihon University School of Dentistry, 1-8-13 Kanda Surugadai, Chiyoda-ku 101-8310, Tokyo, Japan
| | - Amirreza Ghassemi
- Weintraub Center for Reconstructive Biotechnology, Division of Advanced Prosthodontics, UCLA School of Dentistry, Los Angeles, CA 90095, USA; (K.N.); (M.I.); (T.I.); (A.G.); (T.O.)
- Section of Periodontics, Department of Applied Dental Medicine, Southern Illinois University School of Dental Medicine, 2800 College Ave, Alton, IL 62002, USA
| | - Juri Saruta
- Weintraub Center for Reconstructive Biotechnology, Division of Advanced Prosthodontics, UCLA School of Dentistry, Los Angeles, CA 90095, USA; (K.N.); (M.I.); (T.I.); (A.G.); (T.O.)
- Department of Oral Science, Graduate School of Dentistry, Kanagawa Dental University, 82 Inaoka, Yokosuka 238-8580, Kanagawa, Japan
| | - Takahiro Ogawa
- Weintraub Center for Reconstructive Biotechnology, Division of Advanced Prosthodontics, UCLA School of Dentistry, Los Angeles, CA 90095, USA; (K.N.); (M.I.); (T.I.); (A.G.); (T.O.)
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Suzuki N, Takabe T, Yamauchi Y, Koyama S, Koike R, Rikukawa M, Liao WT, Peng WS, Tsai FY. Palladium-catalyzed Mizoroki-Heck reactions in water using thermoresponsive polymer micelles. Tetrahedron 2019. [DOI: 10.1016/j.tet.2019.01.047] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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3
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Wang L, Lu G, Lu Q, Kaplan DL. Controlling Cell Behavior on Silk Nanofiber Hydrogels with Tunable Anisotropic Structures. ACS Biomater Sci Eng 2018; 4:933-941. [DOI: 10.1021/acsbiomaterials.7b00969] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
| | - Guozhong Lu
- Department of Burns and Plastic Surgery, The Third Affiliated Hospital of Nantong University, Wuxi 214041, People’s Republic of China
| | | | - David L. Kaplan
- Department of Biomedical Engineering, Tufts University, Medford, Massachusetts 02155, United States
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van Almen GC, Talacua H, Ippel BD, Mollet BB, Ramaekers M, Simonet M, Smits AIPM, Bouten CVC, Kluin J, Dankers PYW. Development of Non-Cell Adhesive Vascular Grafts Using Supramolecular Building Blocks. Macromol Biosci 2015; 16:350-62. [DOI: 10.1002/mabi.201500278] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2015] [Revised: 10/08/2015] [Indexed: 11/08/2022]
Affiliation(s)
- Geert C. van Almen
- Department of Biomedical Engineering; Laboratory of Chemical Biology, and Institute for Complex Molecular Systems; Eindhoven University of Technology; P.O. Box 513 5600 MB Eindhoven The Netherlands
| | - Hanna Talacua
- Department of Cardio-Thoracic Surgery; University Medical Center Utrecht; 3584 CX Utrecht The Netherlands
| | - Bastiaan D. Ippel
- Department of Biomedical Engineering; Laboratory of Chemical Biology, and Institute for Complex Molecular Systems; Eindhoven University of Technology; P.O. Box 513 5600 MB Eindhoven The Netherlands
| | - Björne B. Mollet
- Department of Biomedical Engineering; Laboratory of Chemical Biology, and Institute for Complex Molecular Systems; Eindhoven University of Technology; P.O. Box 513 5600 MB Eindhoven The Netherlands
| | - Mellany Ramaekers
- Department of Biomedical Engineering; Laboratory of Chemical Biology, and Institute for Complex Molecular Systems; Eindhoven University of Technology; P.O. Box 513 5600 MB Eindhoven The Netherlands
| | - Marc Simonet
- Department of Biomedical Engineering; Soft Tissue Biomechanics and Tissue Engineering and Institute for Complex Molecular Systems; Eindhoven University of Technology; P.O. Box 513 5600 MB Eindhoven The Netherlands
| | - Anthal I. P. M. Smits
- Department of Biomedical Engineering; Soft Tissue Biomechanics and Tissue Engineering and Institute for Complex Molecular Systems; Eindhoven University of Technology; P.O. Box 513 5600 MB Eindhoven The Netherlands
| | - Carlijn V. C. Bouten
- Department of Biomedical Engineering; Soft Tissue Biomechanics and Tissue Engineering and Institute for Complex Molecular Systems; Eindhoven University of Technology; P.O. Box 513 5600 MB Eindhoven The Netherlands
| | - Jolanda Kluin
- Department of Cardio-Thoracic Surgery; University Medical Center Utrecht; 3584 CX Utrecht The Netherlands
| | - Patricia Y. W. Dankers
- Department of Biomedical Engineering; Laboratory of Chemical Biology, and Institute for Complex Molecular Systems; Eindhoven University of Technology; P.O. Box 513 5600 MB Eindhoven The Netherlands
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Surface characteristics and biofunctionality of a novel high-performance, hydrophilic Jeffamine-added fluoro-containing polyimide for biomedical applications. JOURNAL OF POLYMER RESEARCH 2015. [DOI: 10.1007/s10965-014-0628-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Synthesis of Fluorinated Amphiphilic Block Copolymers Based on PEGMA, HEMA, and MMA via ATRP and CuAAC Click Chemistry. INT J POLYM SCI 2014. [DOI: 10.1155/2014/464806] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Synthesis of fluorinated amphiphilic block copolymers via atom transfer radical polymerization (ATRP) and Cu(I) catalyzed Huisgen 1,3-dipolar cycloaddition (CuAAC) was demonstrated. First, a PEGMA and MMA based block copolymer carrying multiple side-chain acetylene moieties on the hydrophobic segment for postfunctionalization was carried out. This involves the synthesis of a series of P(HEMA-co-MMA) random copolymers to be employed as macroinitiators in the controlled synthesis of P(HEMA-co-MMA)-block-PPEGMA block copolymers by using ATRP, followed by a modification step on the hydroxyl side groups of HEMA via Steglich esterification to afford propargyl side-functional polymer, alkyne-P(HEMA-co-MMA)-block-PPEGMA. Finally, click coupling between side-chain acetylene functionalities and 2,3,4,5,6-pentafluorobenzyl azide yielded fluorinated amphiphilic block copolymers. The obtained polymers were structurally characterized by1H-NMR,19F-NMR, FT-IR, and GPC. Their thermal characterizations were performed using DSC and TGA.
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Nakayama Y. Hyperbranched polymeric "star vectors" for effective DNA or siRNA delivery. Acc Chem Res 2012; 45:994-1004. [PMID: 22353143 DOI: 10.1021/ar200220t] [Citation(s) in RCA: 64] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Although gene therapy offers an attractive strategy for treating inherited disorders, current techniques using viral and nonviral delivery systems have not yielded many successful results in clinical trials. Viral vectors such as retroviruses, lentiviruses, and adenoviruses deliver genes efficiently; however, the possibility of negative outcomes from viral transformation cannot be completely ruled out. In contrast, various types of nonviral vectors are attracting considerable attention because they are easier to handle and induce weak immune responses. Cationic polymers, such as polyethylenimine (PEI) and poly(N,N-dimethylaminopropyl acrylamide) (PDMAPAAm), can generate nanoparticles through the formation of polyion complexes, "polyplexes" with DNA. These nonviral systems offer many advantages over viral systems. The primary obstacle to implementing these cationic polymers in an effective gene therapy remains their comparatively inefficient gene transfection in vivo. We describe four strategies for the development of hyperbranched star vectors (SVs) for enhancing DNA or siRNA delivery. The molecular design was performed by living radical polymerization in which the chain length can be controlled by photoirradiation and solution conditions, including concentrations of the monomer or iniferter (a molecule that serves as a combination of initiator, transfer agent, and terminator). The branch composition is controlled by the types of monomers that are added stepwise. In our first strategy, we prepared a series of only cationic PDMAPAAm-based SVs with no branches or 3, 4, or 6 branching numbers. These SVs could form polyion complexes (polyplexes) by mixing with DNA only in aqueous solution. The relative gene expression activity of the delivered DNA increased according to the degree of branching. In addition, increasing the molecular weight of SVs and narrowing their polydispersity index (PDI) improved their activity. For targeting DNA delivery to the specific cells, we modified the SV with ligands. Interestingly, the SV could adsorb the RGD peptide, making gene transfer possible in endothelial cells which are usually refractory to such treatments. The peptide was added to the polyplex solution without covalent derivatization to the SV. The introduction of additional branching by cross-linking using iniferter-induced coupling reactions further improved gene transfection activity. After block copolymerization of PDMAPAAm-based SVs with a nonionic monomer (DMAAm), the blocked SVs (BSVs) produced polyplexes with DNA that had excellent colloidal stability for 1 month, leading to efficient in vitro and in vivo gene delivery. Moreover, BSVs served as carriers for siRNA delivery. BSVs enhanced siRNA-mediated gene silencing in mouse liver and lung. As an alternative approach, we developed a novel gene transfection method in which the polyplexes were kept in contact with their deposition surface by thermoresponsive blocking of the SV. This strategy was more effective than reverse transfection and the conventional transfection methods in solution.
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Affiliation(s)
- Yasuhide Nakayama
- Division of Medical Engineering and Materials, National Cerebral and Cardiovascular Center Research Institute
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Layer-by-Layer Assembled Multilayer Films of Methoxypoly(ethylene glycol)-block-poly(α,L-glutamic acid) and Chitosan with Reduced Cell Adhesion. Macromol Biosci 2011; 11:1211-7. [DOI: 10.1002/mabi.201100053] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2011] [Revised: 04/07/2011] [Indexed: 11/07/2022]
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Preparation of well-defined poly(ether-ester) macromers: photogelation and biodegradability. Acta Biomater 2011; 7:1496-503. [PMID: 21095246 DOI: 10.1016/j.actbio.2010.11.023] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2010] [Revised: 11/12/2010] [Accepted: 11/17/2010] [Indexed: 11/23/2022]
Abstract
Two series of poly(ether-ester)-based bis-functional macromers terminated with acrylate groups and a well-defined number of ester bonds were synthesized. One series had a chain of 1, 3 or 5 ester bonds at both ends of the central poly(ethylene glycol) block (molecular weight, about 1000), while the other had an alternating structure of oligo(ethylene glycol) each of them linked to two ester bonds, in which 6 or 10 ester bonds were incorporated equally in the macromer molecules and the total molecular weight was adjusted by about 1000. Irradiation of all poly(ether-ester) macromers mixed with camphorquinone resulted in the formation of gels. Gel yield increased and hydrophilic properties of the gels produced decreased with irradiation time. The elastic modulus of the gels decreased with the number of ester bonds. Upon incubation in a PBS solution (pH 8.04), all gels were gradually degraded with time. At 3 weeks of incubation, the degradation ratio increased linearly with the number of ester bonds per unit of molecular weight of the macromers. The order of in vivo degradation rates determined from weight loss was similar to that of the in vitro study. Thus, these poly(ether-ester) macromers may be useful for biodegradable biomaterials or tissue engineering scaffolds.
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Muñoz-Bonilla A, van Herk AM, Heuts JPA. Preparation of Hairy Particles and Antifouling Films Using Brush-Type Amphiphilic Block Copolymer Surfactants in Emulsion Polymerization. Macromolecules 2010. [DOI: 10.1021/ma9027257] [Citation(s) in RCA: 83] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Alexandra Muñoz-Bonilla
- Laboratory of Polymer Chemistry, Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven, The Netherlands
- Instituto de Ciencia y Tecnología de Polímeros (CSIC), C/Juan de la Cierva 3, 28006 Madrid, Spain
| | - Alex M. van Herk
- Laboratory of Polymer Chemistry, Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven, The Netherlands
| | - Johan P. A. Heuts
- Laboratory of Polymer Chemistry, Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven, The Netherlands
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Tan BH, Hussain H, Liu Y, He CB, Davis TP. Synthesis and self-assembly of brush-type poly[poly(ethylene glycol)methyl ether methacrylate]-block-poly(pentafluorostyrene) amphiphilic diblock copolymers in aqueous solution. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2010; 26:2361-2368. [PMID: 19785395 DOI: 10.1021/la902816b] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Well-defined fluorinated brush-like amphiphilic diblock copolymers of poly[poly(ethylene glycol)methyl ether methacrylate] (P(PEGMA)) and poly(pentafluorostyrene) (PPFS) have been successfully synthesized via atom transfer radical polymerization (ATRP). The self-assembly behavior of these polymers in aqueous solutions was studied using (1)H NMR, fluorescence spectrometry, static and dynamic light scattering and transmission electron microscopy techniques. The micellar structure comprised of PPFS as the core and brush-like (hydrophobic main chain and hydrophilic branches) polymers as the coronas. The hydrodynamic radius (R(h)) of the micelles in aqueous solution was in the nanometer range, independent of the polymer concentration, consistent with a closed association model. Diblock copolymers with a longer P(PEGMA) block formed micelles with smaller R(h) and lower aggregation numbers consistent with an improved solubilization of the core. The micelles possessed a thick hydration layer as verified by the ratio of the radius of gyration, R(g) to the hydrodynamic radius, R(h). The aggregation number and ratio of R(g) to R(h) were observed to increase with temperature (20-50 degrees C), while the R(h) of the micelle decreased slightly over the same temperature range. An increase in temperature induced the brush-like PEG segments in the corona to dehydrate and shrink while forming micelles with larger aggregation numbers.
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Affiliation(s)
- B H Tan
- Institute of Materials Research and Engineering, Agency for Science, Technology and Research, 3 Research Link, Singapore 117602.
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12
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Nakayama Y, Ishikawa A, Sato R, Uchida K, Kambe N. Photodimerization and Polymerization of PEG Derivatives through Radical Coupling using Photochemistry of Dithiocarbamate. Polym J 2008. [DOI: 10.1295/polymj.pj2008132] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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13
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Nuttelman CR, Rice MA, Rydholm AE, Salinas CN, Shah DN, Anseth KS. Macromolecular Monomers for the Synthesis of Hydrogel Niches and Their Application in Cell Encapsulation and Tissue Engineering. Prog Polym Sci 2008; 33:167-179. [PMID: 19461945 PMCID: PMC2390836 DOI: 10.1016/j.progpolymsci.2007.09.006] [Citation(s) in RCA: 140] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Hydrogels formed from the photoinitiated, solution polymerization of macromolecular monomers present distinct advantages as cell delivery materials and are enabling researchers to three-dimensionally encapsulate cells within diverse materials that mimic the extracellular matrix and support cellular viability. Approaches to synthesize gels with biophysically and biochemically controlled microenvironments are becoming increasingly important, and require strategies to control gel properties (e.g., degradation rate and mechanism) on multiple time and size scales. Furthermore, biological responses of gel-encapsulated cells can be promoted by hydrogel degradation products, as well as by the release of tethered biologically relevant molecules.
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Affiliation(s)
- Charles R Nuttelman
- Department of Chemical and Biological Engineering, University of Colorado, Boulder, CO
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Gromadzki D, Makuška R, Netopilík M, Holler P, Lokaj J, Janata M, Štěpánek P. Comb copolymers of polystyrene-poly(tert-butyl (meth)acrylate) prepared by combination of nitroxide mediated polymerization and photoinduced iniferter technique. Eur Polym J 2008. [DOI: 10.1016/j.eurpolymj.2007.10.024] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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15
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Optimal irradiation wavelength in iniferter-based photocontrolled radical polymerization. ACTA ACUST UNITED AC 2008. [DOI: 10.1002/pola.22787] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Lin CC, Sawicki SM, Metters AT. Free-radical-mediated protein inactivation and recovery during protein photoencapsulation. Biomacromolecules 2007; 9:75-83. [PMID: 18088094 DOI: 10.1021/bm700782c] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Photoencapsulation of protein therapeutics is very attractive for preparing biomolecule-loaded hydrogels for a variety of biomedical applications. However, detrimental effects of highly active radical species generated during photoencapsulation must be carefully evaluated to maintain efficient hydrogel cross-linking while preserving the structure and bioactivity of encapsulated biomolecules. Here, we examine the free-radical-mediated inactivation and incomplete release of proteins from photocurable hydrogels utilizing lysozyme as a conservative model system. Various protein photoencapsulation conditions were tested to determine the factors affecting lysozyme structural integrity and bioactivity. It was found that a portion of the lysozyme becomes conjugated to polymer chains at high photoinitiator concentrations and long polymerization times. We also found that the more hydrophilic photoinitiator Irgacure-2959 (I-2959, 2-hydroxy-1-[4-(hydroxyethoxy)phenyl]-2-methyl-1-propanone) causes more damage to lysozyme compared to the hydrophobic photoinitiator Irgacure-651 (I-651, 2,2-dimethoxy-2-phenylacetophenone), even though I-2959 has been previously shown to be more cytocompatible. Furthermore, while nonacrylated PEG provides only limited protection from the denaturing free radicals that are present during hydrogel curing, acrylated PEG macromers effectively preserve lysozyme structural integrity and bioactivity in the presence of either photoinitiator. Overall, these findings indicate how photopolymerization conditions (e.g., photoinitiator type and concentration, UV exposure time, etc.) must be optimized to obtain a functional hydrogel device that can preserve protein bioactivity and provide maximal protein release.
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Affiliation(s)
- Chien-Chi Lin
- Department of Bioengineering, Clemson University, Clemson, South Carolina, USA
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Zhou YM, Ishikawa A, Okahashi R, Uchida K, Nemoto Y, Nakayama M, Nakayama Y. Deposition transfection technology using a DNA complex with a thermoresponsive cationic star polymer. J Control Release 2007; 123:239-46. [PMID: 17881077 DOI: 10.1016/j.jconrel.2007.08.026] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2007] [Revised: 08/06/2007] [Accepted: 08/19/2007] [Indexed: 11/21/2022]
Abstract
A novel non-viral gene transfection method in which DNA complexes were kept in contact with a deposition surface (deposition transfection) was developed. We designed a novel aqueous thermoresponsive adsorbent material for DNA deposition, which was a star-shaped copolymer with 4-branched chains. Each chain is comprised of a cationic poly(N,N-dimethylaminopropyl acrylamide) (PDMAPAAm) block (Mn: ca. 3000 g x mol(-1)), which formed an inner domain for DNA binding and a thermoresponsive poly(N-isopropylacrylamide) (PNIPAM) block (Mn: ca. 6000 g x mol(-1)), which formed an outer domain for surface adsorption. Complex formation between the copolymer and the luciferase-encoding plasmid DNA occurred immediately upon simple mixing in an aqueous medium; polyplexes approximately 100 nm in size were formed. Because the lower critical solution temperature of the polyplexes was approximately 35 degrees C, they could deposit on the substrate by precipitation from an aqueous solution upon warming, which was confirmed by quartz crystal microbalance (QCM) method and water contact angle measurement. When COS-1 cells were cultured on the polyplex-deposited substrate in a culture medium, the luciferase activity observed was higher than that observed on a DNA-coated substrate with or without the cationic polymer before and after complete adhesion and by conventional solution transfection using the polyplexes. The activity was enhanced with an increase in the charge ratio (surfactant/pDNA) with permissible cellular cytotoxicity.
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Affiliation(s)
- Yue-Min Zhou
- Department of Bioengineering, Advanced Medical Engineering Center, National Cardiovascular Center Research Institute, Japan
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Nakayama Y, Kakei C, Ishikawa A, Zhou YM, Nemoto Y, Uchida K. Synthesis and in Vitro Evaluation of Novel Star-Shaped Block Copolymers (Blocked Star Vectors) for Efficient Gene Delivery. Bioconjug Chem 2007; 18:2037-44. [DOI: 10.1021/bc070045q] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Yasuhide Nakayama
- Department of Bioengineering, Advanced Medical Engineering Center National Cardiovascular Center Research Institute, Division of Biotechnology and Macromolecular Chemistry, Faculty of Engineering, Hokkaido University, Chemical Products Division, Development Department, Bridgestone Company, and Department of Materials Chemistry, Faculty of Science and Technology Ryukoku University
| | - Chiaki Kakei
- Department of Bioengineering, Advanced Medical Engineering Center National Cardiovascular Center Research Institute, Division of Biotechnology and Macromolecular Chemistry, Faculty of Engineering, Hokkaido University, Chemical Products Division, Development Department, Bridgestone Company, and Department of Materials Chemistry, Faculty of Science and Technology Ryukoku University
| | - Ayaka Ishikawa
- Department of Bioengineering, Advanced Medical Engineering Center National Cardiovascular Center Research Institute, Division of Biotechnology and Macromolecular Chemistry, Faculty of Engineering, Hokkaido University, Chemical Products Division, Development Department, Bridgestone Company, and Department of Materials Chemistry, Faculty of Science and Technology Ryukoku University
| | - Yue-Min Zhou
- Department of Bioengineering, Advanced Medical Engineering Center National Cardiovascular Center Research Institute, Division of Biotechnology and Macromolecular Chemistry, Faculty of Engineering, Hokkaido University, Chemical Products Division, Development Department, Bridgestone Company, and Department of Materials Chemistry, Faculty of Science and Technology Ryukoku University
| | - Yasushi Nemoto
- Department of Bioengineering, Advanced Medical Engineering Center National Cardiovascular Center Research Institute, Division of Biotechnology and Macromolecular Chemistry, Faculty of Engineering, Hokkaido University, Chemical Products Division, Development Department, Bridgestone Company, and Department of Materials Chemistry, Faculty of Science and Technology Ryukoku University
| | - Kingo Uchida
- Department of Bioengineering, Advanced Medical Engineering Center National Cardiovascular Center Research Institute, Division of Biotechnology and Macromolecular Chemistry, Faculty of Engineering, Hokkaido University, Chemical Products Division, Development Department, Bridgestone Company, and Department of Materials Chemistry, Faculty of Science and Technology Ryukoku University
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Nakayama Y, Okahashi R, Iwai R, Uchida K. Heparin bioconjugate with a thermoresponsive cationic branched polymer: a novel aqueous antithrombogenic coating material. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2007; 23:8206-11. [PMID: 17571905 DOI: 10.1021/la700323m] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
With a view to reducing the thrombogenic potential of artificial blood-contact devices and natural tissues, we developed a novel aqueous antithrombogenic coating material, comprising a heparin bioconjugate that incorporated a thermoresponsive cationic polymer as a surfactant. The polymer was prepared by the sequential steps of initiator-transfer agent-terminator (iniferter)-based living radical photopolymerization of N-[3-(dimethylamino)propyl]acrylamide, followed by the polymerization of N-isopropylacrylamide from tetra(N,N-diethyldithiocarbamylmethyl)benzene as a multifunctional iniferter. The polymer obtained possessed four branched chains, each consisting of a cationic PDMAPAAm block (Mn: ca. 3000 g.mol(-1)) forming an inner domain for heparin binding and a thermoresponsive PNIPAM block (Mn: ca. 6000 g.mol(-1)) forming an outer domain for surface fixation; bioconjugation of the polymer with heparin occurred immediately upon simple mixing in an aqueous medium. Because the lower critical solution temperature of the heparin bioconjugate was approximately 35 degrees C, it could be coated from an aqueous solution at room temperature. The excellent adsorptivity and high durability of the coating below 37 degrees C was demonstrated on several generally used polymers by wettability measurement and surface chemical compositional analysis, and on collagen sheets and rat skin tissue by heparin staining. Blood coagulation was significantly prevented on the heparin bioconjugate-coated surfaces. The thermoresponsive bioconjugate developed therefore appeared to satisfy the initial requirements for a biocompatible aqueous coating material.
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Affiliation(s)
- Yasuhide Nakayama
- Department of Bioengineering, Advanced Medical Engineering Center, National Cardiovascular Center Research Institute, Hokkaido University, 5-7-1 Fujishiro-dai, Suita, Osaka 565-8565, Japan.
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Zhou Y, Huang H, Nakayama Y. Highly effective in vivo gene transfection by blocked star vector. CONFERENCE PROCEEDINGS : ... ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL CONFERENCE 2007; 2006:501-3. [PMID: 17282226 DOI: 10.1109/iembs.2005.1616457] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Nano-structured four branched, blocked star vector (BSV) was molecular designed by iniferter-based photo-living radical copolymerization method of N,N-dimethylaminopropylacrylamide and then N,N-dimethylacrylamide from four dithiocarbamate-derivatized benzene for a novel gene derivery non-viral vector. The conjugated pDNA complexes were satisfactorily stable in the condition of the electrophoresis. Under the charge ratio of 5/1 (vector/pDNA), complexes of BSV and pDNA (BSV-pDNA) demonstrated satisfied transfection efficiency into COS-1 cells with a little cytotoxicity. Mice injected with BSV-pDNA polyplexes showed a higher level of gene expression in either liver, kidney or spleen using the optimal charge ratio as determined in in vitro. These results suggest the potential use of BSV as a non-viral vector in clinic.
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Affiliation(s)
- Y Zhou
- Department of Bioengineering, Advanced Medical Engineering Center, National Cardiovascular Center Research Institute, 5-7-1 Fujishiro-dai, Suita, Osaka 565-8565, Japan
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Cakmak I, Baykara H, Set B. Synthesis of poly(epichlorohydrin-g-methyl methacrylate) and poly(epichlorohydrin-g-styrene) graft copolymers by a combination of cationic and photopolymerization methods. J Appl Polym Sci 2007. [DOI: 10.1002/app.27217] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Nakayama Y, Masuda T. Development of a polymeric matrix metalloproteinase inhibitor as a bioactive stent coating material for prevention of restenosis. J Biomed Mater Res B Appl Biomater 2006; 80:260-7. [PMID: 16767737 DOI: 10.1002/jbm.b.30592] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Drug-eluting stents have been developed to prevent restenosis derived from excessive growth of smooth muscle cells (SMCs) after stenting. In almost every case, however, less- or non-biocompatible polymers were selected for the platform material for impregnating drugs on the stent strut. Consideration was given principally to the physical properties of the polymers, such as their adhesion to the strut and the drug dispersibility in the polymeric matrix. In this study, we designed a matrix metalloproteinase inhibitor (MMPI)-derivatized hydrophobic polymer (PMMPI) for use as a bioactive material for stent coating. This was a copolymer of n-butylmethacrylate and a vinyl monomer of synthetic MMPI (N-Hydroxy-5-carboxyethylcarbonyloxy-2(S)-methy-4(S)-(4-phenoxybenzoyl)amino-pentanamide: ONO-M11-335) with a molecular weight of about 32,000 and MMPI content of 45 per molecule. The precursor of the MMPI monomer produced significant activity in temporally inhibiting SMC proliferation without any cellular damage. After coating with the PMMPI, adhesion and proliferation of SMCs were manifestly prevented even when a small amount of MMPI was released from the polymer. The MMPI-immobilized surface may thus be effective for inhibiting both adhesion and proliferation of SMCs, which is the first step toward in vivo experimentation. It is very much expected that coating stent struts with PMMPI containing an appropriate combination of impregnated drugs will provide a powerful tool for prevention of restenosis with little cytotoxicity.
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Affiliation(s)
- Yasuhide Nakayama
- Department of Bioengineering, Advanced Medical Engineering Center, National Cardiovascular Center Research Institute, 5-7-1 Fujishiro-dai, Suita, Osaka 565-8565, Japan.
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Mizoguchi I, Ooe Y, Hoshino S, Shimura M, Kasahara T, Kano S, Ohta T, Takaku F, Nakayama Y, Ishizaka Y. Improved gene expression in resting macrophages using an oligopeptide derived from Vpr of human immunodeficiency virus type-1. Biochem Biophys Res Commun 2005; 338:1499-506. [PMID: 16274667 DOI: 10.1016/j.bbrc.2005.10.112] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2005] [Accepted: 10/19/2005] [Indexed: 11/24/2022]
Abstract
Vpr, an accessory gene product of human immunodeficiency virus type-1, is thought to transport a viral DNA from the cytoplasm to the nucleus in resting macrophages. Previously, we reported that a peptide encompassing amino acids 52-78 of Vpr (C45D18) promotes the nuclear trafficking of recombinant proteins that are conjugated with C45D18. Here, we present evidence that C45D18, when conjugated with a six-branched cationic polymer of poly(N,N-dimethylaminopropylacrylamide)-block-oligo(4-aminostyrene) (SV: star vector), facilitates gene expression in resting macrophages. Although there was no difference between SV alone and C45D18-SV with respect to gene transduction into growing cells, C45D18-SV resulted in more than 40-fold greater expression of the exogenous gene upon transduction into chemically differentiated macrophages and human quiescent monocyte-derived macrophages. The data suggest that C45D18 contributes to improving the ability of a non-viral vector to transduce macrophages with exogenous genes and we discuss its further application.
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Affiliation(s)
- Izuru Mizoguchi
- Research Institute, International Medical Center of Japan, 1-21-1 Toyama, Shinjuku-ku, Tokyo 162-8655, Japan
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Cheng Z, Zhu X, Kang ET, Neoh KG. Brush-type amphiphilic diblock copolymers from "living"/controlled radical polymerizations and their aggregation behavior. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2005; 21:7180-5. [PMID: 16042439 DOI: 10.1021/la051038y] [Citation(s) in RCA: 72] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Two brush-type amphiphilic diblock copolymers, poly(poly(ethylene glycol)methyl ether methacrylate-block-polystyrene) (P(PEGMA)-b-PS) and poly(glycidyl methacrylate)-block-poly(poly(ethylene glycol)methyl ether methacrylate) (P(GMA)-b-P(PEGMA)) were synthesized, respectively, via consecutive atom-transfer radical polymerizations (ATRPs) and reversible addition-fragmentation chain-transfer (RAFT) polymerizations. The diblock copolymers were characterized by gel permeation chromatography (GPC), (1)H nuclear magnetic resonance (NMR) spectroscopy, and FT-IR spectroscopy. The aggregation behavior of the two amphiphilic diblock copolymers in water was also studied. Scanning electron and transmission electron microscopic images revealed that spherical micelles (40-80 nm in diameter) from self-assembly of the P(PEGMA)-b-PS copolymers and wormlike micelles (60-120 nm in length and 20-30 nm in diameter) from self-assembly of the P(GMA)-b-P(PEGMA) copolymers were prevalent. The spherical P(PEGMA)-b-PS micelles could self-assemble gradually into giant aggregates of several micrometers in diameter.
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Affiliation(s)
- Zhenping Cheng
- Department of Chemical and Biomolecular Engineering, National University of Singapore, Kent Ridge, Singapore 119260
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Ibusuki S, Iwamoto Y, Matsuda T. System-Engineered Cartilage Using Poly(N-isopropylacrylamide)-Grafted Gelatin as in Situ-Formable Scaffold: In Vivo Performance. ACTA ACUST UNITED AC 2003; 9:1133-42. [PMID: 14670101 DOI: 10.1089/10763270360728044] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Our previous study showed that cartilaginous tissue can be engineered in vitro with articular chondrocytes and poly(N-isopropylacrylamide)-grafted gelatin. This short-term in vivo study for cartilage repair was performed to screen a candidate method for a long-term study. In our previous in vitro study, however, two potential problems with the tissue-engineered cartilage were identified: (1). leakage of the transplant due to temperature decline and (2). concave deformation of transplant due to compressive loading. To solve these problems, we investigated in this study the usefulness of suturing with two different covering materials (periosteum or collagen film) and preculturing an engineered tissue for 2 weeks. PNIPAAm-gelatin-based engineered cartilage samples were evaluated at 5 weeks after operation by gross and microscopic examination. Leakage occurred only in specimens without precultured tissue and with a collagen film. Minimal surface deformation occurred in all specimens with precultured tissue. The score on gross examination showed that transplants with precultured tissue acquired a higher score than did the others. Histological evaluation showed a minimal foreign-body response of PNIPAAm-gelatin in all specimens and higher maturity as a cartilaginous tissue in specimens with precultured tissue. These results indicate that transplantation with precultured tissue may be a suitable method for a long-term in vivo study.
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Affiliation(s)
- Shinichi Ibusuki
- Department of Biomedical Engineering, Graduate School of Medicine, Kyushu University, Fukuoka, Japan
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Matsuda T, Nagase J, Ghoda A, Hirano Y, Kidoaki S, Nakayama Y. Phosphorylcholine-endcapped oligomer and block co-oligomer and surface biological reactivity. Biomaterials 2003; 24:4517-27. [PMID: 12922161 DOI: 10.1016/s0142-9612(03)00344-2] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Phosphorylcholine (PC)-endcapped oligomer and block co-oligomer were prepared by employing a photoiniferter-based quasi-living polymerization technique. The designed oligomer had a PC polar head group attached to an alkylene chain at one end of the molecule and an oligo(styrene) (oligoST) segment at the other end. In the co-oligomer, an oligo(N,N-dimethylacrylamide) (oligoDMAAm) segment was inserted between both ends of the oligomer mentioned above. Surface coating of these amphiphilic substances, using an appropriate coating procedure, resulted in a very hydrophilic characteristic, suggesting that the oligoST anchored on the substrate and the PC polar head group was exposed to or located on the outer coating layer. Non-cell adhesivity in serum-containing medium was observed, while slightly reduced protein adsorption was observed. Thus, PC-endcapped oligomer and block co-oligomer appear to function as a biocompatible coating.
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Affiliation(s)
- Takehisa Matsuda
- National Cardiovascular Center Research Institute, Department of Bioengineering, 5-7-1, Fujishiro-dai, Suita, Osaka 565-8565, Japan.
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Hyeong Kwon O, Kikuchi A, Yamato M, Okano T. Accelerated cell sheet recovery by co-grafting of PEG with PIPAAm onto porous cell culture membranes. Biomaterials 2003; 24:1223-32. [PMID: 12527263 DOI: 10.1016/s0142-9612(02)00469-6] [Citation(s) in RCA: 125] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Fabrication of functional tissue constructs from designed three-dimensional structures of cells using the layered method of cultured cell sheets could prove to be an attractive approach to tissue engineering. Rapid recovery of cell sheets is considered to be important as a basic technology for practical assembly of tissue-mimicking structures. To accelerate required culture substrate hydrophilic/hydrophobic functional changes according to the hydrated/dehydrated structural changes in response to culture temperature alteration, poly(N-isopropylacrylamide) (PIPAAm) was grafted with poly(ethylene glycol) (PEG) onto porous culture membranes by electron beam irradiation. Analyses by attenuated total reflection-Fourier transform infrared and electron spectroscopy for chemical analysis revealed that PIPAAm and PEG were successfully grafted to surfaces of porous membranes. PIPAAm-grafted porous membranes (PIPAAm-PM) were compared with porous membranes co-grafted with various amounts of PEG and PIPAAm (PIPAAm(PEG)-PM) for cell sheet detachment experiments. Approximately 35min incubation at 20 degrees C was required to completely detach cell sheets from PIPAAm-PM in a static condition, while only 19min to detach cell sheets from PIPAAm(PEG0.5%)-PM, which is co-grafted with PIPAAm and 0.5wt% of PEG. With porous membranes, water molecules were accessed by the PIPAAm molecules grafted on the surfaces from both underneath and peripheral to the attached cell sheet, resulting in more rapid hydration of grafted PIPAAm molecules and detachment of cell sheet than that for nonporous tissue culture polystyrene (TCPS) dish. With PIPAAm(PEG)-PMs, grafted PEG chains should accelerate the diffusion of water molecules to PIPAAm grafts, showing more rapid detachment of cell sheet compare to PIPAAm-PMs.
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Affiliation(s)
- Oh Hyeong Kwon
- Institute of Advanced Biomedical Engineering and Science, Tokyo Women's Medical University, 8-1 Kawadacho, Shinjuku, 162-8666, Tokyo, Japan
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Mizutani M, Arnold SC, Matsuda T. Liquid, phenylazide-end-capped copolymers of epsilon-caprolactone and trimethylene carbonate: preparation, photocuring characteristics, and surface layering. Biomacromolecules 2002; 3:668-75. [PMID: 12099809 DOI: 10.1021/bm0101670] [Citation(s) in RCA: 62] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Photoreactive phenylazide-end-capped liquid copolymers were prepared by ring-opening copolymerization of epsilon-caprolactone (CL) and trimethylene carbonate (TMC) at an equimolar monomer feed ratio in the presence of a polyol, namely, a low-molecular-weight alcohol (di-, tri-, and tetraol) or poly(ethylene glycol) (PEG) as an initiator and tin(II) 2-ethylhexanoate as a catalyst, followed subsequently by phenylazide derivatization at their hydroxyl terminus. These tri- and tetrabranched liquid copolymers (precursors) with a molecular weight from approximately 2500 to 7000 g/mol were cross-linked to yield insoluble solids by ultraviolet (UV) light irradiation. The photocuring rate increased with increasing functionality of phenylazide and UV intensity and decreasing thickness of the liquid film of precursors. The photo-cross-linkability of phenylazide-derivatized liquid copolymers was found to be higher than that of the corresponding coumarin-derivatized liquid copolymers. Poly(lactide) (PLA) films surface-layered with photocured copolymers were prepared by coating surfaces with phenylazide-derivatized copolymers and their subsequent photoirradiation. Endothelial cells adhered well on the nontreated PLA and low-molecular-weight alcohol-based copolymer-layered and photocured films. Little cell adhesion was observed on the hydrolytically surface-eroded PLA film and the PEG-based copolymer-layered film. When a phenylazide-derivatized hexapeptide with the cell-adhesion tripeptidyl sequence, Arg-Gly-Asp (RGD), common to cell adhesive proteins, was photoimmobilized on these surfaces, the surfaces became cell adhesive. Microarchitectured surfaces, which were prepared by sequential procedures of surface coating and photocuring using a photomask with lattice windows, produced regionally differentiated cell adhesiveness.
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Affiliation(s)
- Manabu Mizutani
- Department of Bioengineering, National Cardiovascular Center Research Institute, 5-7-1 Fujishiro-dai, Suita, Osaka 565-8565, Japan
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Luo N, Hutchison JB, Anseth KS, Bowman CN. Surface-Initiated Photopolymerization of Poly(ethylene glycol) Methyl Ether Methacrylate on a Diethyldithiocarbamate-Mediated Polymer Substrate. Macromolecules 2002. [DOI: 10.1021/ma011487e] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Ning Luo
- Department of Chemical Engineering, University of Colorado, Boulder, Colorado 80309-0424; Howard Hughes Medical Institute, University of Colorado, Boulder, Colorado 80309-0424; and Department of Restorative Dentistry, University of Colorado Health Sciences Center, Denver, Colorado 80045-0508
| | - J. Brian Hutchison
- Department of Chemical Engineering, University of Colorado, Boulder, Colorado 80309-0424; Howard Hughes Medical Institute, University of Colorado, Boulder, Colorado 80309-0424; and Department of Restorative Dentistry, University of Colorado Health Sciences Center, Denver, Colorado 80045-0508
| | - Kristi S. Anseth
- Department of Chemical Engineering, University of Colorado, Boulder, Colorado 80309-0424; Howard Hughes Medical Institute, University of Colorado, Boulder, Colorado 80309-0424; and Department of Restorative Dentistry, University of Colorado Health Sciences Center, Denver, Colorado 80045-0508
| | - Christopher N. Bowman
- Department of Chemical Engineering, University of Colorado, Boulder, Colorado 80309-0424; Howard Hughes Medical Institute, University of Colorado, Boulder, Colorado 80309-0424; and Department of Restorative Dentistry, University of Colorado Health Sciences Center, Denver, Colorado 80045-0508
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