title: Labeling of fibronectin by fluorescent and paramagnetic nanoprobes for exploring the extracellular matrix: bioconjugate synthesis optimization and biochemical characterization.
abstract: In this study, fibronectin-nanoparticles bioconjugates are developed and characterized. Multilabeled nanoparticles are composed of a core of the rare-earth oxide Gd(2)O(3):Tb(3+), capped with a set of Rhodamine B isothiocyanate encapsulated in a silica matrix and functionalized by a carboxylated polyethylene glycol shell. These nanoparticles are stabilized in aqueous solution and are found to contain about 400 carboxyl groups on their surface. Nanoparticle bioconjugation with highly purified human plasma fibronectin (Fn) is mediated by 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide and N-hydroxysuccinimide, resulting in an amide linkage between the carboxylic acid-terminated surface of the nanoparticle and the primary amine of Fn. The bioconjugation temperature and pH are optimized. The Local structure and global conformation of fibronectin-nanoparticle bioconjugates (FnNP*) are studied by fluorescence spectroscopy and enzymatic sites accessibility. Protein biochemical functionalities are globally conserved, and the protein is actually labeled. Elaboration of such complexes provides a promising bimodal contrasting agent for in vivo imaging.
authors.affiliation: Laboratoire de Physicochimie des Polymères et des Interfaces (LPPI-EA 2528), Institut des matériaux (I-MAT-FD 4122), Université de Cergy-Pontoise, 5 mail Gay-Lussac Neuville-sur-Oise, 95031 Cergy-Pontoise Cedex, France.
authors.forename: Céline
authors.initials: C
authors.lastname: Hoffmann
authors.forename: Anne-Charlotte
authors.initials: AC
authors.lastname: Faure
authors.forename: Cedric
authors.initials: C
authors.lastname: Vancaeyzeele
authors.forename: Stéphane
authors.initials: S
authors.lastname: Roux
authors.forename: Olivier
authors.initials: O
authors.lastname: Tillement
authors.forename: Emmanuel
authors.initials: E
authors.lastname: Pauthe
authors.forename: Fabrice
authors.initials: F
authors.lastname: Goubard
mesh_terms: D005353:Fibronectins / Q000097:blood*; D005453:Fluorescence; D006801:Humans; D006863:Hydrogen-Ion Concentration; D008280:Magnetics; D053758:Nanoparticles / Q000737:chemistry*; D011487:Protein Conformation; D013050:Spectrometry, Fluorescence; D013194:Staining and Labeling; D013499:Surface Properties; D013696:Temperature
chemical_list: D005353:Fibronectins