title: Photomediated crosslinking of C6-cinnamate derivatized type I collagen.
abstract: Synthesis and characterization of cinnamated Type I collagen and its related mechanical properties after photomediated crosslinking were investigated in detail. Using an EDC/NHS conjugation method, collagen was chemically modified to incorporate a photosensitive cinnamate moiety. The cinnamated collagen was fully characterized by 1H NMR, UV-vis, and circular dichroism (CD) spectroscopy, as well as by rheological and mechanical analyses. Cinnamated collagens with varying degrees of derivatization retained collagen triple helical structure. The rheological spectra of collagen solutions demonstrate that the storage modulus decreases with increasing cinnamate content, owing to a decrease in physical crosslinking. The kinetics of the crosslinking process in both hydrated gels and dry films were monitored by UV-vis spectroscopy and confirmed that crosslinking was complete within 60 min of irradiation. The uniaxial stress-strain behavior of crosslinked collagen films, including Young's modulus and ultimate tensile strength, was comparable to values reported for glutaraldehyde-crosslinked monomeric collagen films. These data demonstrate that derivatization of collagen with photosensitive cinnamate moieties provides a facile route for solid-state crosslinking, thereby improving the mechanical properties of collagen and enhancing the potential applicability of collagen-based materials in tissue engineering and drug delivery.
authors.affiliation: Department of Polymer Science and Engineering, School of Chemistry and Chemical Technology, Shanghai Jiao-Tong University, Shanghai 200240, People's Republic of China.
authors.forename: Chang-Ming
authors.initials: CM
authors.lastname: Dong
authors.forename: Xiaoyi
authors.initials: X
authors.lastname: Wu
authors.forename: Jeffrey
authors.initials: J
authors.lastname: Caves
authors.forename: Shyam S
authors.initials: SS
authors.lastname: Rele
authors.forename: Benjamin S
authors.initials: BS
authors.lastname: Thomas
authors.forename: Elliot L
authors.initials: EL
authors.lastname: Chaikof
mesh_terms: D001672:Biocompatible Materials / Q000032:analysis / Q000737:chemistry / Q000528:radiation effects; D002934:Cinnamates / Q000032:analysis / Q000737:chemistry* / Q000528:radiation effects*; D024042:Collagen Type I / Q000032:analysis / Q000737:chemistry* / Q000528:radiation effects*; D003432:Cross-Linking Reagents / Q000737:chemistry* / Q000528:radiation effects; D004343:Drug Implants / Q000737:chemistry; D004548:Elasticity / Q000528:radiation effects; D008027:Light; D008422:Materials Testing; D010777:Photochemistry / Q000379:methods*; D033081:Shear Strength; D013718:Tensile Strength / Q000528:radiation effects; D023822:Tissue Engineering / Q000379:methods
chemical_list: D001672:Biocompatible Materials; D002934:Cinnamates; D024042:Collagen Type I; D003432:Cross-Linking Reagents; D004343:Drug Implants; C029010:cinnamic acid