Landi Elena, Tampieri Anna, Celotti Giancarlo, Sprio Simone, Sandri Monica, Logroscino Giandomenico
ISTEC-CNR, Institute of Science and Technology for Ceramics, National Research Council, via Granarolo 64, 48018 Faenza (RA), Italy.
Acta Biomater. 2007 Nov;3(6):961-9. doi: 10.1016/j.actbio.2007.05.006. Epub 2007 Jun 19.
Porous apatites, which during resorption can release in situ Sr ions, were prepared to associate an anti-osteoporotic action with the peculiar features of the inorganic phase constituting the bone. Sr-substituted hydroxyapatite (SrHA) powder was directly synthesized using the classical neutralization route, but including Sr ions, and characterized. The higher solubility of SrHA granules of 400-600 microm size, potentially usable as a bone filler, was assessed compared with that of analogous stoichiometric HA granules. The Sr released in synthetic body fluid became constant after 1 week. The Ca release is improved for SrHA compared with stoichiometric HA, due to the higher solubility of the first material. Porous scaffolds with micro-macro interconnected porosity, which mimic the morphology of the spongy bone, were prepared by the impregnation of cellulose sponges with suspensions of the powder and a specific sintering process. A compressive strength of 4.52+/-1.40 MPa was obtained for SrHA scaffolds characterized with 45 vol.% of porosity. Promising biomedical applications, such as resorbable bone filler or bone substitute releasing in situ Sr ions for a prolonged time, can be hypothesized for the SrHA materials when pathologies related with Sr deficiency are present.
制备了在吸收过程中可原位释放锶离子的多孔磷灰石，以使抗骨质疏松作用与构成骨骼的无机相的独特特性相关联。采用经典的中和路线直接合成了含锶离子的锶取代羟基磷灰石（SrHA）粉末，并对其进行了表征。评估了尺寸为400 - 600微米、可能用作骨填充剂的SrHA颗粒与类似化学计量比的HA颗粒相比更高的溶解度。在合成体液中释放的锶在1周后变得恒定。由于第一种材料的溶解度更高，与化学计量比的HA相比，SrHA的钙释放得到了改善。通过用粉末悬浮液浸渍纤维素海绵并采用特定的烧结工艺，制备了具有微-宏相互连通孔隙率、模拟松质骨形态的多孔支架。孔隙率为45体积%的SrHA支架的抗压强度为4.52±1.40兆帕。当存在与锶缺乏相关的病症时，可以设想SrHA材料具有如可吸收骨填充剂或长时间原位释放锶离子的骨替代物等有前景的生物医学应用。
