Tapsir Zafirah, Jamaludin Farah H, Pingguan-Murphy Belinda, Saidin Syafiqah
1 Biomedical Sciences Laboratory, Faculty of Biosciences & Medical Engineering (FBME), 54702 Universiti Teknologi Malaysia , Skudai, Johor, Malaysia.
2 Biomedical Engineering Department, Faculty of Engineering, 236783 University of Malaya , Kuala Lumpur, Malaysia.
J Biomater Appl. 2018 Feb;32(7):987-995. doi: 10.1177/0885328217744081. Epub 2017 Nov 29.
The utilisation of hydroxyapatite and collagen as bioactive coating materials could enhance cells attachment, proliferation and osseointegration. However, most methods to form crystal hydroxyapatite coating do not allow the incorporation of polymer/organic compound due to production phase of high sintering temperature. In this study, a polydopamine film was used as an intermediate layer to immobilise hydroxyapatite-collagen without the introduction of high sintering temperature. The surface roughness, coating adhesion, bioactivity and osteoblast attachment on the hydroxyapatite-collagen coating were assessed as these properties remains unknown on the polydopamine grafted film. The coating was developed by grafting stainless steel 316L disks with a polydopamine film. Collagen type I fibres were then immobilised on the grafted film, followed by the biomineralisation of hydroxyapatite. The surface roughness and coating adhesion analyses were later performed by using AFM instrument. An Alamar Blue assay was used to determine the cytotoxicity of the coating, while an alkaline phosphatase activity test was conducted to evaluate the osteogenic differentiation of human fetal osteoblasts on the coating. Finally, the morphology of cells attachment on the coating was visualised under FESEM. The highest RMS roughness and coating adhesion were observed on the hydroxyapatite-collagen coating (hydroxyapatite-coll-dopa). The hydroxyapatite-coll-dopa coating was non-toxic to the osteoblast cells with greater cells proliferation, greater level of alkaline phosphate production and more cells attachment. These results indicate that the immobilisation of hydroxyapatite and collagen using an intermediate polydopamine is identical to enhance coating adhesion, osteoblast cells attachment, proliferation and differentiation, and thus could be implemented as a coating material on orthopaedic and dental implants.
将羟基磷灰石和胶原蛋白用作生物活性涂层材料可增强细胞附着、增殖和骨整合。然而，由于高烧结温度的生产阶段，大多数形成晶体羟基磷灰石涂层的方法不允许聚合物/有机化合物的掺入。在本研究中，聚多巴胺膜用作中间层，以固定羟基磷灰石-胶原蛋白，而无需引入高烧结温度。评估了羟基磷灰石-胶原蛋白涂层的表面粗糙度、涂层附着力、生物活性和成骨细胞附着情况，因为这些特性在聚多巴胺接枝膜上尚不清楚。通过在不锈钢316L圆盘上接枝聚多巴胺膜来制备涂层。然后将I型胶原纤维固定在接枝膜上，随后进行羟基磷灰石的生物矿化。随后使用原子力显微镜（AFM）仪器进行表面粗糙度和涂层附着力分析。使用阿拉玛蓝测定法来确定涂层的细胞毒性，同时进行碱性磷酸酶活性测试以评估人胎儿成骨细胞在涂层上的成骨分化。最后，在场发射扫描电子显微镜（FESEM）下观察细胞在涂层上的附着形态。在羟基磷灰石-胶原蛋白涂层（羟基磷灰石-胶原-多巴胺）上观察到最高的均方根粗糙度和涂层附着力。羟基磷灰石-胶原-多巴胺涂层对成骨细胞无毒，具有更高的细胞增殖、更高水平的碱性磷酸酶产生和更多的细胞附着。这些结果表明，使用中间聚多巴胺固定羟基磷灰石和胶原蛋白可同样增强涂层附着力、成骨细胞附着、增殖和分化，因此可作为骨科和牙科植入物的涂层材料。
