title: Molecular level interactions in brushite-aminoacids composites.
abstract: The interaction of aminoacids (Glycine, Proline, Lysine) with brushite based bone cements has been investigated by several techniques (FTIR spectroscopy, Thermogravimetry-TG, Scanning Electron Microscopy-SEM, mechanical properties studies), with the aim to elucidate the properties of the resulting composite materials and the interaction occurring at molecular level between the inorganic matrix and the organic moieties. Brushite phase is predominantly obtained also in the presence of aminoacids added during preparation of the bone cement. Focusing on Glycine incorporation, the presence of a fraction of bulk Glycine, weakly interacting with the inorganic matrix, together with Glycine specifically interacting with adsorption sites can be envisaged, as pointed out by FT IR and thermogravimetric data. In detail, FT-IR data evidenced changes in shape and position of bands associated to stretching modes of the carboxylic groups in Glycine structure, which can be explained by the coordination of these functional groups with the Ca ions in the matrix. Heating this composite at controlled temperature results in the detection of a condensation products, either cyclic condensation product, either dipeptide. Diffuse and not specific H-bonding seems to be the main form of interaction of Proline and Lysine with brushite. Due to the coordination with Ca ions here described, Glycine can act as retardant during brushite preparation, allowing good workability of the resulting composite.
authors: Dept. of Civil, Chemical and Environmental Engineering-DICCA, University of Genova, P.le J.F. Kennedy 1, I-16129 Genova, Italy.
authors: Alberto
authors: A
authors: Lagazzo
authors: Dept. of Civil, Chemical and Environmental Engineering-DICCA, University of Genova, P.le J.F. Kennedy 1, I-16129 Genova, Italy.
authors: Fabrizio
authors: F
authors: Barberis
authors: Dept. of Earth, Environment and Life Science-DISTAV, University of Genova, C.so Europa 26, I-16132 Genova, Italy.
authors: Cristina
authors: C
authors: Carbone
authors: Dept. of Civil, Chemical and Environmental Engineering-DICCA, University of Genova, P.le J.F. Kennedy 1, I-16129 Genova, Italy.
authors: Gianguido
authors: G
authors: Ramis
authors: Dept. of Civil, Chemical and Environmental Engineering-DICCA, University of Genova, P.le J.F. Kennedy 1, I-16129 Genova, Italy. Electronic address: Elisabetta.Finocchio@unige.it.
authors: Elisabetta
authors: E
authors: Finocchio
mesh_terms: D000596:Amino Acids / Q000737:chemistry*; D002130:Calcium Phosphates / Q000737:chemistry*; D005998:Glycine / Q000737:chemistry; D006860:Hydrogen Bonding; D008239:Lysine / Q000737:chemistry; D008855:Microscopy, Electron, Scanning; D011392:Proline / Q000737:chemistry; D017550:Spectroscopy, Fourier Transform Infrared; D055672:Static Electricity; D013818:Thermogravimetry
chemical_list: D000596:Amino Acids; D002130:Calcium Phosphates; D011392:Proline; D008239:Lysine; C494366:calcium phosphate, dibasic, dihydrate; D005998:Glycine
keywords: Brushite; FT-IR spectroscopy; Glycine; Lysine; Proline