Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Departamento de Química, Brazil.
Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Departamento de Química, Brazil.
Mater Sci Eng C Mater Biol Appl. 2019 Jun;99:762-769. doi: 10.1016/j.msec.2019.02.023. Epub 2019 Feb 7.
SrCO is frequently used as Sr source in ceramic cements, but its application as bioactive coating for metallic implants has not been explored yet. Aiming at rapid osteointegration and because of the well-known Sr effects on bone metabolism, researchers have sought to design Sr-containing biomaterials. In this context, developing simple techniques to prepare Sr-based coatings is a must nowadays. Here, we describe the use of a bioinspired lipid-mediated approach to grow SrCO hybrid films on Ti surfaces at room temperature. To obtain these coatings, we applied the Langmuir-Blodgett technique to deposit phospholipid films with high degree of organization on Ti. In this way, we expected that controlled SrCO crystal growth could be templated by the array of nucleation points arising from electrostatic interaction between Sr and the phospholipid polar heads. To control surface composition and the amount of Sr released from the coatings, we also promoted CaCO co-precipitation in the hybrid films. We characterized the hybrid coatings in terms of morphology, chemical structure, wettability, and ability to release Sr upon immersion in biological medium. In vitro osteoblast culture on mixed SrCO/CaCO films revealed that the osteogenic response depended on surface composition, as indicated by alkaline phosphatase activity overexpression, which is an early indicator of osteoblast differentiation. Results showed that the mixed SrCO/CaCO hybrid film created a synergic environment for osteoblasts, and that proper Sr release associated with a Ca-rich environment might have optimized the Sr anabolic effect. In conclusion, we have proposed a bioinspired and versatile technique to grow hybrid films that can control surface composition and Sr release. Our results open an opportunity to explore the use of SrCO-based coatings for rapid metallic implant osteointegration.
SrCO 通常被用作陶瓷水泥中的 Sr 源，但尚未探索其在金属植入物生物活性涂层中的应用。由于众所周知的 Sr 对骨代谢的影响，研究人员一直致力于设计含 Sr 的生物材料。在这种情况下，如今必须开发制备 Sr 基涂层的简单技术。在这里，我们描述了一种仿生脂质介导的方法，即在室温下在 Ti 表面上生长 SrCO 杂化膜。为了获得这些涂层，我们应用 Langmuir-Blodgett 技术在 Ti 上沉积具有高度组织化的磷脂膜。通过这种方式，我们期望通过 Sr 与磷脂极性头之间的静电相互作用产生的成核点的阵列来模板控制 SrCO 晶体的生长。为了控制表面组成和从涂层中释放的 Sr 量，我们还促进了混合膜中 CaCO 的共沉淀。我们从形态、化学结构、润湿性和在生物介质中浸泡时释放 Sr 的能力等方面对杂化涂层进行了表征。在混合 SrCO/CaCO 薄膜上进行成骨细胞培养的结果表明，成骨反应取决于表面组成，如碱性磷酸酶活性过表达所指示的，这是成骨细胞分化的早期指标。结果表明，混合 SrCO/CaCO 杂化膜为成骨细胞创造了协同环境，与富含 Ca 的环境相关的适当 Sr 释放可能优化了 Sr 合成代谢作用。总之，我们提出了一种仿生且多功能的技术来生长可以控制表面组成和 Sr 释放的杂化膜。我们的结果为探索基于 SrCO 的涂层在快速金属植入物骨整合中的应用提供了机会。
