title: Mass Spectrometry and Ion Mobility Characterization of Bioactive Peptide-Synthetic Polymer Conjugates.
abstract: The bioconjugate BMP2-(PEO-HA)2, composed of a dendron with two monodisperse poly(ethylene oxide) (PEO) branches terminated by a hydroxyapatite binding peptide (HA), and a focal point substituted with a bone growth stimulating peptide (BMP2), has been comprehensively characterized by mass spectrometry (MS) methods, encompassing matrix-assisted laser desorption ionization (MALDI), electrospray ionization (ESI), tandem mass spectrometry (MS2), and ion mobility mass spectrometry (IM-MS). MS2experiments using different ion activation techniques validated the sequences of the synthetic, bioactive peptides HA and BMP2, which contained highly basic amino acid residues either at the N-terminus (BMP2) or C-terminus (HA). Application of MALDI-MS, ESI-MS, and IM-MS to the polymer-peptide biomaterial confirmed its composition. Collision cross-section measurements and molecular modeling indicated that BMP2-(PEO-HA)2exists in several folded and extended conformations, depending on the degree of protonation. Protonation of all basic sites of the hybrid material nearly doubles its conformational space and accessible surface area.
authors.affiliation: Departments of †Chemistry and ‡Polymer Science, The University of Akron , Akron, Ohio 44325, United States.
authors.forename: Ahlam
authors.initials: A
authors.lastname: Alalwiat
authors.affiliation: Departments of †Chemistry and ‡Polymer Science, The University of Akron , Akron, Ohio 44325, United States.
authors.forename: Wen
authors.initials: W
authors.lastname: Tang
authors.affiliation: Departments of †Chemistry and ‡Polymer Science, The University of Akron , Akron, Ohio 44325, United States.
authors.forename: Selim
authors.initials: S
authors.lastname: Gerişlioğlu
authors.affiliation: Departments of †Chemistry and ‡Polymer Science, The University of Akron , Akron, Ohio 44325, United States.
authors.forename: Matthew L
authors.identifier: 0000-0003-4089-6916
authors.initials: ML
authors.lastname: Becker
authors.affiliation: Departments of †Chemistry and ‡Polymer Science, The University of Akron , Akron, Ohio 44325, United States.
authors.forename: Chrys
authors.identifier: 0000-0002-7916-4782
authors.initials: C
authors.lastname: Wesdemiotis
mesh_terms: D000595:Amino Acid Sequence; D001665:Binding Sites; D055396:Bone Morphogenetic Protein 2 / Q000737:chemistry*; D017886:Durapatite / Q000737:chemistry; D010455:Peptides / Q000737:chemistry*; D011092:Polyethylene Glycols / Q000737:chemistry*; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods; D053719:Tandem Mass Spectrometry / Q000379:methods
chemical_list: D055396:Bone Morphogenetic Protein 2; D010455:Peptides; D011092:Polyethylene Glycols; D017886:Durapatite