title: Gauging and Tuning Cross-Linking Kinetics of Catechol-PEG Adhesives via Catecholamine Functionalization.
abstract: The curing time of an adhesive material is determined by the polymerization and cross-linking kinetics of the adhesive formulation and needs to be optimized for the particular application. Here, we explore the possibility of tuning the polymerization kinetics and final mechanical properties of tissue-adhesive PEG gels formed by polymerization of end-functionalized star-PEGs with catecholamines with varying substituents. We show strong differences in cross-linking time and cohesiveness of the final gels among the catecholamine-PEG variants. Installation of an electron-withdrawing but π-electron donating chloro substituent on the catechol ring resulted in faster and more efficient cross-linking, while opposite effects were observed with the strongly electron-withdrawing nitro group. Chain substitution slowed down the kinetics and hindered cross-linking due either to chain breakdown (β-OH group, in norepinephrine) or intramolecular cyclization (α-carboxyl group, in DOPA). Interesting perspectives derive from use of mixtures of catecholamine-PEG precursors offering further opportunities for fine-tuning of the curing parameters. These are interesting properties for the application of catecholamine-PEG gels as tissue glues or biomaterials for cell encapsulation.
authors.affiliation: Max- Planck Institut für Polymerforschung , Ackermannweg 10, 55128 Mainz, Germany.
authors.forename: Julieta I
authors.initials: JI
authors.lastname: Paez
authors.affiliation: Max- Planck Institut für Polymerforschung , Ackermannweg 10, 55128 Mainz, Germany.
authors.forename: Oya
authors.initials: O
authors.lastname: Ustahüseyin
authors.affiliation: Max- Planck Institut für Polymerforschung , Ackermannweg 10, 55128 Mainz, Germany.
authors.forename: Cristina
authors.initials: C
authors.lastname: Serrano
authors.affiliation: Max- Planck Institut für Polymerforschung , Ackermannweg 10, 55128 Mainz, Germany.
authors.forename: Xuan-Anh
authors.initials: XA
authors.lastname: Ton
authors.affiliation: Max- Planck Institut für Polymerforschung , Ackermannweg 10, 55128 Mainz, Germany.
authors.forename: Zahid
authors.initials: Z
authors.lastname: Shafiq
authors.affiliation: Max- Planck Institut für Polymerforschung , Ackermannweg 10, 55128 Mainz, Germany.
authors.forename: Günter K
authors.initials: GK
authors.lastname: Auernhammer
authors.affiliation: Department of Chemical Sciences, University of Naples Federico II , Via Cintia, I-80126 Naples, Italy.
authors.forename: Marco
authors.initials: M
authors.lastname: d'Ischia
authors.affiliation: Max- Planck Institut für Polymerforschung , Ackermannweg 10, 55128 Mainz, Germany.|INM - Leibniz Institute for New Materials , Campus D2 2, 66123 Saarbrücken, Germany.|Saarland University , 66123 Saarbrücken, Germany.
authors.forename: Aránzazu
authors.initials: A
authors.lastname: del Campo
mesh_terms: D001672:Biocompatible Materials / Q000737:chemistry*; D002395:Catecholamines / Q000737:chemistry*; D002396:Catechols / Q000737:chemistry*; D003432:Cross-Linking Reagents / Q000737:chemistry*; D004295:Dihydroxyphenylalanine / Q000737:chemistry; D005782:Gels; D007700:Kinetics; D009638:Norepinephrine / Q000737:chemistry; D011092:Polyethylene Glycols / Q000737:chemistry*; D058105:Polymerization; D013329:Structure-Activity Relationship; D014014:Tissue Adhesives / Q000737:chemistry*; D023822:Tissue Engineering
chemical_list: D001672:Biocompatible Materials; D002395:Catecholamines; D002396:Catechols; D003432:Cross-Linking Reagents; D005782:Gels; D014014:Tissue Adhesives; D011092:Polyethylene Glycols; D004295:Dihydroxyphenylalanine; D009638:Norepinephrine