Carbon-centered radicals in γ-irradiated bone substituting biomaterials based on hydroxyapatite.
Gamma irradiated synthetic hydroxyapatite, bone substituting materials NanoBone(®) and HA Biocer were examined using EPR spectroscopy and compared with powdered human compact bone. In every case, radiation-induced carbon centered radicals were recorded, but their molecular structures and concentrations differed. In compact bone and synthetic hydroxyapatite the main signal assigned to the CO(2)                                   (-) anion radical was stable, whereas the signal due to the CO(3)                                   (3-) radical dominated in NanoBone(®) and HA Biocer just after irradiation. However, after a few days of storage of these samples, also a CO(2)                                   (-) signal was recorded. The EPR study of irradiated compact bone and the synthetic graft materials suggest that their microscopic structures are different. In FT-IR spectra of NanoBone(®), HA Biocer and synthetic hydroxyapatite the HPO(4)                                   (2-) and CO(3)                                   (2-) in B-site groups are detected, whereas in compact bone signals due to collagen dominate.
Institute of Nuclear Chemistry and Technology, Dorodna 16, 03-195, Warsaw, Poland. j.sadlo@ichtj.waw.pl
Jaroslaw
J
Sadlo
Grazyna
G
Strzelczak
Malgorzata
M
Lewandowska-Szumiel
Marcin
M
Sterniczuk
Lukasz
L
Pajchel
Jacek
J
Michalik
D001672:Biocompatible Materials / Q000737:chemistry / Q000528:radiation effects; D018786:Bone Substitutes / Q000737:chemistry* / Q000528:radiation effects*; D002244:Carbon / Q000737:chemistry* / Q000528:radiation effects; D020099:Coated Materials, Biocompatible / Q000737:chemistry / Q000528:radiation effects*; D004338:Drug Combinations; D017886:Durapatite / Q000737:chemistry* / Q000528:radiation effects; D004578:Electron Spin Resonance Spectroscopy; D005609:Free Radicals / Q000528:radiation effects; D005720:Gamma Rays; D006801:Humans; D011208:Powders; D012822:Silicon Dioxide / Q000737:chemistry / Q000528:radiation effects; D017550:Spectroscopy, Fourier Transform Infrared
D001672:Biocompatible Materials; D018786:Bone Substitutes; D020099:Coated Materials, Biocompatible; D004338:Drug Combinations; D005609:Free Radicals; C492956:HA-Biocer; C534915:NanoBone; D011208:Powders; D002244:Carbon; D012822:Silicon Dioxide; D017886:Durapatite