TY - GEN A1 - Imam, Neama Gomaa A1 - Harfouche, Messaoud A1 - Abdelghany, Amr Mohamed A1 - Flege, Jan Ingo T1 - Effect of Cu incorporation in silicate and modified borate bioglass materials for health applications: insights from synchrotron-based x-ray absorption spectroscopy T2 - Discover Materials N2 - This contribution investigates the effect of variable copper incorporation (x = 0.2, 1.0, 2.0, and 4.0) in silicate (45 SiO2, 24.5 CaO, 24.5 Na2O, 6P2O5wt%) and modified borate (45 B2O3, 24.5 CaO, 24.5 Na2O, 6P2O5wt%) bioglass materials to be used for bone bonding applications. X-ray absorption fine structure spectroscopy (XAFS) has been used to determine the oxidation states and local coordination structure of Cu atoms in silicate-based and borate-based glasses at the Cu K-edge (~ 8979 eV). The oxidation states of Cu atoms have been determined by near-edge XAFS (XANES) fingerprinting employing reference standard compounds of Cu. Cu (I) and Cu (II) XANES spectra of the standard reference compounds were linearly combined to fit the normalized μ(E) data of the collected XANES spectra using linear combination fitting (LCF approach). The obtained results prove that most of the silicate glass samples contain Cu2O almost exclusively, while modified borate glass samples contain a significant mixture of Cu2O and CuO phases. According to the literature, the remarkable coexistence of Cu2O and CuO phases within the borate sample, particularly when x = 4, promotes the conversion process to allow the more facile formation of hydroxy carbonate apatite (HCA). The best fit structural parameters derived from extended-XAFS (EXAFS) fitting show that the ratio between Cu (I) and Cu (II) in borate glass agreed well with that extracted from XANES analysis. XANES and EXAFS conclude that borate glass with x = 4 is the most suitable composition for bone bonding applications. KW - Bioglass KW - Local coordination KW - Oxidation state KW - Silicate KW - Borate KW - Synchrotron radiation KW - Short-range order KW - XANES KW - LCF KW - EXAFS Y1 - 2024 U6 - https://doi.org/10.1007/s43939-024-00103-8 SN - 2730-7727 VL - 4 IS - 1 PB - Springer Science and Business Media LLC ER -