Hou Jingwen, Liu Yongjia, Han Zhihui, Song Dianwen, Zhu Bangshang
Instrumental Analysis Center, Shanghai Jiao Tong University, Shanghai 200240, China.
Department of Stomatology, Xuhui Central Hospital, 996 Huaihaizhong Road, Shanghai 200031, China.
Mater Sci Eng C Mater Biol Appl. 2021 Jan;120:111655. doi: 10.1016/j.msec.2020.111655. Epub 2020 Oct 22.
Hydroxyapatite (HA) combined with antimicrobial agents for biomedical application can effectively avoid the bacteria infection, while HA have the good performance. In this study, we prepared silver-hydroxyapatite (Ag-HA) nanocomposites using a one-pot method consisting of three sequential steps of wet chemical precipitation, ion exchange, and a silver mirror reaction. The HA nanoparticles used as the precursor for Ag ion doping were first synthesised by wet chemical precipitation. Next, Ag absorbed on HA surface through ion exchange reaction. Glucose was then added to initiate the silver mirror reaction, which made the Ag ions reduce to Ag and Ag nanoparticles in situ formed on HA nanoparticles. Subsequently, Ag-HA nanocomposites with different Ag content were prepared. X-ray diffraction, SEM, EDX mapping and TEM imaging confirmed that spherical Ag nanoparticles ~20-40 nm in diameter were adhered to the surface of HA nano-rods (0.4-0.8 μm in length and 15-40 nm in diameter). The Ag content (1.9-15.2 wt%) in the Ag-HA nanocomposites was adjusted by varying the feeding Ag/Ca molar ratio (2.0-20%). The cell viability evaluation in vitro proved that Ag-HA nanocomposites had low cytotoxicity to L929 normal cells. Meanwhile, the antibacterial examinations in vitro demonstrated that Ag-HA nanocomposites had obvious antibacterial effects on Gram-positive bacteria, Gram-negative bacteria, and fungus. The antibacterial results were dose-dependent on the accumulation of silver content. The Ag-HA nanocomposites loaded PMMA resins also demonstrated a potential antibacterial activity against S. mutans. This paper presents a convenient and bio-friendly approach for preparing Ag-HA nanocomposites with adjustable Ag content, which are a promising material for biomedical applications.
羟基磷灰石（HA）与抗菌剂结合用于生物医学应用时，能有效避免细菌感染，同时HA性能良好。在本研究中，我们采用一锅法制备了银-羟基磷灰石（Ag-HA）纳米复合材料，该方法包括湿化学沉淀、离子交换和银镜反应三个连续步骤。用作银离子掺杂前驱体的HA纳米颗粒首先通过湿化学沉淀法合成。接下来，银通过离子交换反应吸附在HA表面。然后加入葡萄糖引发银镜反应，使银离子还原为银，并在HA纳米颗粒上原位形成银纳米颗粒。随后，制备了具有不同银含量的Ag-HA纳米复合材料。X射线衍射、扫描电子显微镜、能谱映射和透射电子显微镜成像证实，直径约20-40nm的球形银纳米颗粒附着在HA纳米棒表面（长度为0.4-0.8μm，直径为15-40nm）。通过改变进料银/钙摩尔比（2.0-20%）来调节Ag-HA纳米复合材料中的银含量（1.9-15.2wt%）。体外细胞活力评估证明，Ag-HA纳米复合材料对L929正常细胞具有低细胞毒性。同时，体外抗菌检测表明，Ag-HA纳米复合材料对革兰氏阳性菌、革兰氏阴性菌和真菌具有明显的抗菌作用。抗菌结果与银含量的积累呈剂量依赖性。负载有PMMA树脂的Ag-HA纳米复合材料对变形链球菌也表现出潜在的抗菌活性。本文提出了一种方便且生物友好的方法来制备银含量可调的Ag-HA纳米复合材料，它们是生物医学应用中有前景的材料。
