Gomes Sandrine, Kaur Amandeep, Grenèche Jean-Marc, Nedelec Jean-Marie, Renaudin Guillaume
Université Clermont Auvergne, SIGMA Clermont, Institut de Chimie de Clermont-Ferrand, BP 10448, F-63000 Clermont-Ferrand, France; CNRS, UMR 6296, ICCF, F-63178 Aubière, France.
Institut des Molécules et Matériaux du Mans, UMR CNRS 6283, Université du Maine, 72085 Le Mans Cedex, France.
Acta Biomater. 2017 Mar 1;50:78-88. doi: 10.1016/j.actbio.2016.12.011. Epub 2016 Dec 10.
Biphasic calcium phosphates (BCPs) are bioceramics composed of hydroxyapatite (HAp, Ca(PO)(OH)) and beta-Tricalcium Phosphate (β-TCP, Ca(PO)). Because their chemical and mineral composition closely resembles that of the mineral component of bone, they are potentially interesting candidates for bone repair surgery, and doping can advantageously be used to improve their biological behavior. However, it is important to describe the doping mechanism of BCP thoroughly in order to be able to master its synthesis and then to fully appraise the benefit of the doping process. In the present paper we describe the ferric doping mechanism: the crystallographic description of our samples, sintered at between 500°C and 1100°C, was provided by Rietveld analyses on X-ray powder diffraction, and the results were confirmed using X-ray absorption spectroscopy and Fe Mössbauer spectrometry. The mechanism is temperature-dependent, like the previously reported zinc doping mechanism. Doping was performed on the HAp phase, at high temperature only, by an insertion mechanism. The Fe interstitial site is located in the HAp hexagonal channel, shifted from its centre to form a triangular three-fold coordination. At lower temperatures, the Fe are located at the centre of the channel, forming linear two-fold coordinated O-Fe-O entities. The knowledge of the doping mechanism is a prerequisite for a correct synthesis of the targeted bioceramic with the adapted (Ca+Fe)/P ratio, and so to be able to correctly predict its potential iron release or magnetic properties.
Biphasic calcium phosphates (BCPs) are bioceramics composed of hydroxyapatite (HAp, Ca(PO)(OH)) and beta-Tricalium Phosphate (β-TCP, Ca(PO)). Because their chemical and mineral composition closely resembles that of the mineral component of bone, they are potentially interesting candidates for bone repair surgery. Doping can advantageously be used to improve their biological behaviors and/or magnetic properties; however, it is important to describe the doping mechanism of BCP thoroughly in order to fully appraise the benefit of the doping process. The present paper scrutinizes in detail the incorporation of ferric cation in order to correctly interpret the behavior of the iron-doped bioceramic in biological fluid. The temperature dependent mechanism has been fully described for the first time. And it clearly appears that temperature can be used to design the doping according to desired medical application: blood compatibility, remineralization, bactericidal or magnetic response.
双相磷酸钙（BCP）是由羟基磷灰石（HAp，Ca(PO)(OH)）和β-磷酸三钙（β-TCP，Ca(PO)）组成的生物陶瓷。由于它们的化学和矿物组成与骨的矿物成分非常相似，它们是骨修复手术中潜在的有吸引力的候选材料，并且掺杂可有利地用于改善其生物学行为。然而，为了能够掌握其合成方法并充分评估掺杂过程的益处，全面描述BCP的掺杂机制很重要。在本文中，我们描述了铁掺杂机制：通过对X射线粉末衍射进行Rietveld分析，提供了在500°C至1100°C之间烧结的我们样品的晶体学描述，并使用X射线吸收光谱和Fe穆斯堡尔光谱对结果进行了确认。该机制与先前报道的锌掺杂机制一样，取决于温度。仅在高温下通过插入机制对HAp相进行掺杂。Fe间隙位点位于HAp六方通道中，从其中心偏移以形成三角形三重配位。在较低温度下，Fe位于通道中心，形成线性双重配位的O-Fe-O实体。了解掺杂机制是正确合成具有合适（Ca+Fe）/P比的目标生物陶瓷的先决条件，从而能够正确预测其潜在的铁释放或磁性。
双相磷酸钙（BCP）是由羟基磷灰石（HAp，Ca(PO)(OH)）和β-磷酸三钙（β-TCP，Ca(PO)）组成的生物陶瓷。由于它们的化学和矿物组成与骨的矿物成分非常相似，它们是骨修复手术中潜在的有吸引力的候选材料。掺杂可有利地用于改善其生物学行为和/或磁性；然而，为了充分评估掺杂过程的益处，全面描述BCP的掺杂机制很重要。本文详细研究了铁阳离子的掺入，以便正确解释铁掺杂生物陶瓷在生物流体中的行为。首次全面描述了温度依赖性机制。显然，温度可用于根据所需的医学应用设计掺杂：血液相容性、再矿化、杀菌或磁响应。
