Hydroxyapatite (HA) and related materials have been frequently studied as ceramic-based bone graft materials due to their outstanding biocompatibility and osteoconduction. Since the bones are the load supporting parts of a vertebrate, they must have good fracture toughness (K_IC) to avoid fracture at high loading during limb movements. However, the main shortcomings of HA are the poor fracture toughness and brittleness. The mechanical properties of HA need to be improved for orthopedic applications, therefore it is often fabricated with other materials into a composite. This article focuses on the effect of carbon nanostructures (CNSs) especially graphene nanoplatelets (GNPs) on the mechanical, physicochemical properties and in-vitro bio-functional performances of HA. We provide an overview on the preparation and characterization of the HA–GNPs composites. To conclude, the challenges in the fabrication of multi-substituted HA–GNPs composites and future outlooks in the biomedical domain are discussed.

中文翻译：

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羟基磷灰石-石墨烯纳米片复合材料作为骨移植替代品的概述：力学行为和体外生物功能

羟基磷灰石（HA）和相关材料由于其出色的生物相容性和骨传导性而经常被研究为陶瓷基骨移植材料。由于骨骼是脊椎动物的负荷支撑部分，因此骨骼必须具有良好的断裂韧性（K _IC），以避免肢体运动时高负荷下的断裂。但是，HA的主要缺点是断裂韧性和脆性差。HA在骨科应用中的机械性能需要提高，因此通常将其与其他材料制成复合材料。本文重点研究碳纳米结构（CNS）特别是石墨烯纳米片（GNP）对机械，物理化学性质和体外的影响HA的生物功能性能。我们提供了HA-GNPs复合材料的制备和表征的概述。总之，讨论了多取代HA-GNPs复合材料的制造挑战以及生物医学领域的未来前景。