title: Comparative performance of collagen nanofibers electrospun from different solvents and stabilized by different crosslinkers.
abstract: Collagen electrospun scaffolds well reproduce the structure of the extracellular matrix (ECM) of natural tissues by coupling high biomimetism of the biological material with the fibrous morphology of the protein. Structural properties of collagen electrospun fibers are still a debated subject and there are conflicting reports in the literature addressing the presence of ultrastructure of collagen in electrospun fibers. In this work collagen type I was successfully electrospun from two different solvents, trifluoroethanol (TFE) and dilute acetic acid (AcOH). Characterization of collagen fibers was performed by means of SEM, ATR-IR, Circular Dichroism and WAXD. We demonstrated that collagen fibers contained a very low amount of triple helix with respect to pristine collagen (18 and 16% in fibers electrospun from AcOH and TFE, respectively) and that triple helix denaturation occurred during polymer dissolution. Collagen scaffolds were crosslinked by using 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide (EDC), a commonly employed crosslinker for electrospun collagen, and 1,4-butanediol diglycidyl ether (BDDGE), that was tested for the first time in this work as crosslinking agent for collagen in the form of electrospun fibers. We demonstrated that BDDGE successfully crosslinked collagen and preserved at the same time the scaffold fibrous morphology, while scaffolds crosslinked with EDC completely lost their porous structure. Mesenchymal stem cell experiments demonstrated that collagen scaffolds crosslinked with BDDGE are biocompatible and support cell attachment.
authors.affiliation: Department of Chemistry ''G. Ciamician'' and National Consortium of Materials Science and Technology (INSTM, Bologna RU), University of Bologna, Bologna, Italy.
authors.forename: Andrea
authors.initials: A
authors.lastname: Fiorani
authors.forename: Chiara
authors.initials: C
authors.lastname: Gualandi
authors.forename: Silvia
authors.initials: S
authors.lastname: Panseri
authors.forename: Monica
authors.initials: M
authors.lastname: Montesi
authors.forename: Maurilio
authors.initials: M
authors.lastname: Marcacci
authors.forename: Maria Letizia
authors.initials: ML
authors.lastname: Focarete
authors.forename: Adriana
authors.initials: A
authors.lastname: Bigi
mesh_terms: D000818:Animals; D001672:Biocompatible Materials / Q000737:chemistry; D002072:Butylene Glycols; D002478:Cells, Cultured; D003094:Collagen / Q000737:chemistry* / Q000187:drug effects; D003432:Cross-Linking Reagents / Q000494:pharmacology*; D004355:Drug Stability; D004595:Electroplating / Q000379:methods; D005109:Extracellular Matrix / Q000737:chemistry; D008422:Materials Testing; D057139:Nanofibers / Q000737:chemistry*; D011817:Rabbits; D012997:Solvents / Q000494:pharmacology*; D023822:Tissue Engineering / Q000379:methods; D054457:Tissue Scaffolds / Q000737:chemistry
chemical_list: D001672:Biocompatible Materials; D002072:Butylene Glycols; D003432:Cross-Linking Reagents; D012997:Solvents; D003094:Collagen; C014376:1,4-bis(2,3-epoxypropoxy)butane