人体干细胞繁殖生长能力增强超音速火焰喷涂纳米氧化钛-羟基磷灰石涂层

Enhanced Proliferation and Growth of Human Stem Cells on the Surface of HVOF-sprayed Nano TiO_2-HA Coatings

超音速火焰(HVOF)喷涂纳米氧化钛加10%羟基磷灰石(HA)(n-TiO2-10%HA)粉末制备的生物医学涂层有望取代大气等离子喷涂的HA涂层。选用这种方法的原因为TiO2在人体内的稳定性很高(即没有溶解),另外,在Ti-6Al-4V的基板上的结合强度超过APS-HA涂层2倍。为了探索这些新材料和涂层的生物表现,在超音速火焰喷涂的n-TiO2和n-TiO2-10%HA的涂层表面上进行了从1到21天的人体间质干细胞(hMSCs)培养,APS的HA涂层和未涂层的Ti-6Al-4V合金基体作为对照。对hMSCs的活性特征进行了以下分析:阿拉莫尔艾迪布尔细胞的繁殖;生化碱性磷酸酶(ALP)活性的分析;细胞骨架组织(通过荧光/共聚焦显微镜)及细胞/基体的互动(通过扫描电子显微镜(SEM))。细胞繁殖和生化分析表明,在n-TiO2-10%HA涂层上培养的hMSCs表现出了类似的或优于APS-HA涂层上的hMSCs生物活性。细胞骨架组织在超音速火焰喷涂n-TiO2-10%HA涂层表面上具有更高的细胞繁殖和附着程度。这些结果对下一代高性能长寿命热喷涂生物涂层具有重要意义。

Biomedical thermal spray coatings produced via high velocity oxy-fuel （HVOF） from nanostructured titania （n-TiO2） and 10% hydroxyapatite （HA） （n-TiO2-10%HA） powders have been engineered as possible future alternatives to HA coatings deposited via air plasma spray （APS）. This approach was chosen due to the stability of TiO2 in the human body （i.e., no dissolution） and bond strength values on Ti-6Al-4V substrates more than two times higher than those of APS HA coatings. To explore the bioperformance of these novel materials and coatings, human mesenchymal stem cells （hMSCs） were cultured from 1 to 21 days on the surface of HVOF-sprayed n-TiO2 and n-TiO2-10%HA coatings. APSHA coatings and uncoated Ti-6Al-4V substrates were employed as controls. The active profiles of the hMSCs were evaluated for cell proliferation by Alamar Bleu assay, biochemical analysis of alkaline phosphatase （ALP） activity, cytoskeleton organization （fluorescent/confocal microscopy） and cell/substrate interaction via scanning electron microscopy （SEM）. Cell proliferation and biochemical analysis indicated that the hMSCs cultured on n-TiO2-10%HA coatings exhibited similar or superior levels of bioactivity to hMSC cultured on APS HA. The cytoskeleton organization demonstrated a higher degree of cell proliferation and attachment on the HVOF-sprayed n-TiO2-10%HA coatings. These results are considered promising for engineering improved performance and increased longevity in the next generation of thermally sprayed biomedical coatings.