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Covalent surface modification of titanium oxide with different adhesive peptides: Surface characterization and osteoblast-like cell adhesion

Tue, 30 Jun 2009 22:00:00 GMT

Covalent surface modification of titanium oxide with different adhesive peptides: Surface characterization and osteoblast-like cell adhesion Dettin, Monica; Bagno, Andrea; Gambaretto, Roberta; Iucci, Giovanna; Conconi, Maria Teresa; Tuccitto, Nunzio; Menti, Anna Michela; Grandi, Claudio; Di Bello, Carlo; Licciardello, Antonino; Polzonetti, Giovanni 2009-07 Journal of biomedical materials research 90A 35-45 A fundamental goal in the field of implantology is the design of innovative devices suitable for promoting, implant-to-tissue integration. This result can be achieved by means of surface modifications aimed at optimizing tissue regeneration. In the framework of oral and orthopedic implantology, surface modifications concern both the optimization of titanium/titanium alloy surface roughness and the attachment of biochemical factors able to guide cellular adhesionand/or growth. This article focuses on the covalent attachment of two different adhesive peptides to rough titanium disks. The capability of biomimetic surfaces to increase osteoblast adhesion and the specificity of their biological activity due to the presence of cell adhesion signal-motif have also been investigated. In addition, surface analyses by profilometry, X-ray photoelectron spectroscopy, and time of flight-secondary ion mass spectrometry have been carried out to investigate the effects and modifications induced by grafting procedures. (C) 2008 Wiley Periodicals, Inc. J Biomed Mater Res 90A:35-45, 2009

Assessment of novel chemical strategies for covalent attachment of adhesive peptides to rough titanium surfaces: XPS analysis and biological evaluation

Sat, 31 Oct 2009 23:00:00 GMT

Assessment of novel chemical strategies for covalent attachment of adhesive peptides to rough titanium surfaces: XPS analysis and biological evaluation Dettin, Monica; Thushari, Herat; Gambaretto, Roberta; Iucci, Giovanna; Battocchio, Chiara; Bagno, Andrea; Ghezzo, Francesca; Di Bello, Carlo; Polzonetti, Giovanni; Di Silvio, Lucy 2009-11 Journal of Biomedical Materials Research A 91A 463-479 Bioactive molecules have been proposed to promote beneficial interactions at bone-implant interfaces for enhancing integration. The main objective of this study was to develop novel methods to functionalize oxidized titanium surfaces by the covalent immobilization of bioactive peptides, through selective reaction involving single functional groups. In the first protocol, an aminoalkylsilane was covalently linked to the Ti oxide layer, followed by covalent binding of glutaric anhydride to the free NH2 groups. The carboxylic group Of glutaric anhydride was used to condense the free N-terminal group of the side-chain protected peptide sequence. Finally, the Surface was treated with trifluoroacetic acid to deprotect side-chain groups. In the second protocol, the peptide was directly anchored to the Ti oxide surface via UV activation of an arylazide peptide analogue. X-ray photoelectron spectroscopy analyses confirmed that modifications induced onto surface composition were in agreement with the reactions performed. The peptide density of each biomimetic Surface was determined on the basis of radiolabeling and XPS derived reaction yields. The in vitro cellular response of the biomimetic surfaces was evaluated using a primary human osteoblast cell model. Cell adhesion, proliferation, differentiation, and mineralization were examined at initial-, short-, and long-time periods. In was shown that the biomimetic surface obtained through photoprobe-marked analogue that combines an easily-performed modification provides a favorable surface for an enhanced cellular response. (C) 2008 Wiley Periodicals, Inc. J Biomed Mater Res 91A: 463-479, 200

Self-Assembled Monolayers Based on Pd-Containing Organometallic Thiols:Preparation and Structural Characterization

Fri, 31 Jul 2009 22:00:00 GMT

Self-Assembled Monolayers Based on Pd-Containing Organometallic Thiols:Preparation and Structural Characterization Vitaliano, Rosa; Fratoddi, Ilaria; Venditti, Iole; Roviello, Giuseppina; Battocchio, Chiara; Polzonetti, Giovanni; Russo, Maria Vittoria 2009-08 The Journal of phisical chemistry A 113 14730–14740 Multilayers and self-assembled monolayers of on-purpose-preparedorganometallic thiolates, trans-[Pd(PBu3)(2)(SCOCH3)(2)], trans-[(C6H5CC)Pd(PBu3)(2)(SCOCH3)], and trans, trans-[(CH3COS)Pd(PBu3)(2)-(CC-C6H4-C6H4-C C)(PBu3)(2)Pd(SCOCH3)] Were deposited onto goldsurfaces. High-resolution X-ray photoelectron spectroscopy andnear-edge X-ray absorption fine structure measurements allowed us toassess the anchoring of the organometallic thiols onto gold substrates;the interaction occurring at the interface; and their molecularorientation oil the surface with tilt angles of about 30 degrees-40degrees, depending on. the investigated molecule. The molecule packingdensity/coverage was also assessed.

Palladium nanoparticles supported on polyvinylpyridine: Catalyticactivity in Heck-type reactions and XPS structural studies

Sat, 28 Feb 2009 23:00:00 GMT

Palladium nanoparticles supported on polyvinylpyridine: Catalyticactivity in Heck-type reactions and XPS structural studies Evangelisti, Claudio; Panziera, Nicoletta; Pertici, Paolo; Vitulli, Giovanni; Salvadori, Piero; Battocchio, Chiara; Polzonetti, Giovanni 2009-03 Journal of catalysis 262 287-293 Palladium nanoparticles, obtained by metal vapour synthesis (MVS), weredeposited on cross-linked polyvinylpyridine. The Pd/PVPy system showedhigh catalytic activity in the Heck C-C coupling reaction of iodo- andbromo-arenes (iodobenzene, bromobenzene, p-nitrobromobenzene,p-bromoacetophenone, p-(methoxy)bromobenzene) with alkyl acrylates(methyl acrylate, n-butyl acrylate, ethylhexyltrans-3-(4-methoxyphenyl)acrylate) at 100 degrees C-175 degrees Cworking under nitrogen atmosphere as well as in air. The catalyst isstable and the leaching of metal in solution is very low. When reused,the recovered Pd/PVPy maintains the catalytic activity of the pristinematerial. XPS structural studies performed on the starting catalyst aswell as on the recovered one indicate the presence of a interactionbetween the basic nitrogen of the pyridine present in the polymer andthe metal. (C) 2009 Elsevier Inc. All rights reserved.

Assessment of novel chemical strategies for covalent attachment ofadhesive peptides to rough titanium surfaces: XPS analysis andbiological evaluation

Sat, 31 Oct 2009 23:00:00 GMT

Assessment of novel chemical strategies for covalent attachment ofadhesive peptides to rough titanium surfaces: XPS analysis andbiological evaluation Dettin, Monica; Herath, Thushari; Gambaretto, Roberta; Iucci, Giovanna; Battocchio, Chiara; Bagno, Andrea; Ghezzo, Francesca; Di Bello, Carlo; Polzonetti, Giovanni; Di Silvio, Lucy 2009-11 Journal of biomedical materials research 91A 463-479 Bioactive molecules have been proposed to promote beneficialinteractions at bone-implant interfaces for enhancing integration. Themain objective of this study was to develop novel methods tofunctionalize oxidized titanium surfaces by the covalent immobilizationof bioactive peptides, through selective reaction involving singlefunctional groups. In the first protocol, an aminoalkylsilane wascovalently linked to the Ti oxide layer, followed by covalent bindingof glutaric anhydride to the free NH2 groups. The carboxylic group Ofglutaric anhydride was used to condense the free N-terminal group ofthe side-chain protected peptide sequence. Finally, the Surface wastreated with trifluoroacetic acid to deprotect side-chain groups. Inthe second protocol, the peptide was directly anchored to the Ti oxidesurface via UV activation of an arylazide peptide analogue. X-rayphotoelectron spectroscopy analyses confirmed that modificationsinduced onto surface composition were in agreement with the reactionsperformed. The peptide density of each biomimetic Surface wasdetermined on the basis of radiolabeling and XPS derived reactionyields. The in vitro cellular response of the biomimetic surfaces wasevaluated using a primary human osteoblast cell model. Cell adhesion,proliferation, differentiation, and mineralization were examined atinitial-, short-, and long-time periods. In was shown that thebiomimetic surface obtained through photoprobe-marked analogue thatcombines an easily-performed modification provides a favorable surfacefor an enhanced cellular response. (C) 2008 Wiley Periodicals, Inc. JBiomed Mater Res 91A: 463-479, 2009

Covalent surface modification of titanium oxide with different adhesivepeptides: Surface characterization and osteoblast-like cell adhesion

Wed, 31 Dec 2008 23:00:00 GMT

Covalent surface modification of titanium oxide with different adhesivepeptides: Surface characterization and osteoblast-like cell adhesion Dettin, Monica; Bagno, Andrea; Gambaretto, Roberta; Iucci, Giovanna; Conconi, Maria Teresa; Tuccitto, Nunzio; Menti, Anna Michela; Grandi, Claudio; Di Bello, Carlo; Licciardello, Antonino; Polzonetti, Giovanni 2009 Journal of biomedical materials research. Part A 90A 35-45 A fundamental goal in the field of implantology is the design ofinnovative devices suitable foil promoting, implant-to-tissueintegration. This result can be achieved by means of surfacemodifications aimed at optimizing tissue regeneration. In the frameworkof oral and orthopedic implantology, surface modifications concern boththe optimization of titanium/titanium alloy surface roughness and theattachment of biochemical factors able to guide cellular adhesionand/or growth. This article focuses on the covalent attachment of twodifferent adhesive peptides to rough titanium disks. The capability ofbiomimetic surfaces to increase osteoblast adhesion and the specificityof their biological activity due to the presence of cell adhesionsignal-motif have also been investigated. In addition, surface analysesby profilometry, X-ray photoelectron spectroscopy, and time offlight-secondary ion mass spectrometry have been carried out toinvestigate the effects and modifications induced by graftingprocedures. (C) 2008 Wiley Periodicals, Inc. J Biomed Mater Res 90A:35-45, 2009