One of the main problems that remain in the implant industry is poor osseointegration due to bioinertness of implants. In order to promote bioactivity, calcium (Ca), phosphorus (P) and strontium (Sr) were incorporated into a TiO₂ porous layer produced by micro-arc oxidation. Ca and P as bioactive elements are already well reported in the literature, however, the knowledge of the effect of Sr is still limited. In the present work, the effect of various amounts of Sr was evaluated and the morphology, chemical composition and crystal structure of the oxide layer were investigated. Furthermore, in vitro studies were carried out using human osteoblast-like cells.

The oxide layer formed showed a triplex structure, where higher incorporation of Sr increased Ca/P ratio, amount of rutile and promoted the formation of SrTiO₃ compound. Biological tests revealed that lower concentrations of Sr did not compromise initial cell adhesion neither viability and interestingly improved mineralization. However, higher concentration of Sr (and consequent higher amount of rutile) showed to induce collagen secretion but with compromised mineralization, possibly due to a delayed mineralization process or induced precipitation of deficient hydroxyapatite. Ca-P-TiO₂ porous layer with less concentration of Sr seems to be an ideal candidate for bone implants.

植入物工业中仍然存在的主要问题之一是由于植入物的生物惰性而导致的骨整合不良。为了促进生物活性，将钙（Ca），磷（P）和锶（Sr）掺入通过微弧氧化产生的TiO ₂多孔层中。Ca和P作为生物活性元素已在文献中得到了很好的报道，但是，关于Sr作用的知识仍然有限。在目前的工作中，评估了各种数量的Sr的影响，并研究了氧化层的形貌，化学组成和晶体结构。此外，使用人成骨细胞样细胞进行了体外研究。

形成的氧化物层显示出三层结构，其中更高的Sr掺入量增加了Ca / P比，金红石的含量并促进了SrTiO ₃化合物的形成。生物学测试表明，较低的Sr浓度不会损害初始细胞黏附力，也不会降低生存能力，并且不会显着改善矿化作用。但是，较高的Sr浓度（以及随之而来的较高的金红石含量）显示诱导胶原蛋白分泌，但矿化程度降低，这可能是由于矿化过程延迟或羟基磷灰石缺乏引起的沉淀。Sr浓度较低的Ca-P-TiO ₂多孔层似乎是植入骨的理想选择。