Background: With excellent shape memory and superelastic properties, shape memory alloy (SMA) is an ideal actuator, and it can form smart structure for different applications in medical field. However, SMA devices cause apparent thermal damage to the surrounding tissues when it works in vivo, making the application of smart structure that is composed of SMA actuator in vivo is greatly limited. Methods: In this paper, coating (APA) with PLA as the main body to limit the heat conduction, a multifunctional Ag nanoparticles (AgNPs)/polylactic acid (PLA)/Al2O3 was synthesized. The Al2O3 layer was formed by micro-arc oxidation (MAO) and AgNPs were synthesized by silver nitrate and ethylene glycol. Scanning electron microscopy, transmission electron microscope, and Fourier transform infrared spectra were applied to analyze the morphology and characterization of APA coating. The antimicrobial activity, thermal insulation activity, and biocompatibility of APA coating were furtherly explored and verified through animal experiments and immunohistochemistry. Results: With different particle sizes and concentrations of AgNPs, APA multi-functional films were successfully prepared. The Al2O3 layer was closely combined with SMA and formed a porous surface, so the PLA and AgNPs layers can firmly adhere to SMA, thus reducing the release of nickel ions in SMA. AgNPs gave APA coating excellent antibacterial activity and effectively inhibited the growth of Staphylococcus aureus. In addition, coupled with the low thermal conductivity of PLA and Al2O3, AgNPs were tightly anchored on the surface of PLA, which has high infrared reflectivity, making the APA coating obtain good thermal insulation performance. Conclusion: We have successfully prepared the APA coating and obtained the optimum amount of AgNPs, which makes it have good thermal insulation performance, good antibacterial activity and good biocompatibility, which provides a new prospect for the application of SMA.
展开▼
机译：背景：具有优异的形状记忆和超弹性性能，形状记忆合金（SMA）是理想的执行器，可以形成智能结构，用于医疗领域的不同应用。然而，当它在体内工作时，SMA器件对周围组织的显而易见的热损坏，使得智能结构的应用在体内由SMA执行器组成的智能结构非常有限。方法：在本文中，用PLA作为主体的涂层（APA）为主体限制导热，合成多官能Ag纳米颗粒（AgNP）/聚乳酸（PLA）/ Al 2 O 3。通过微弧氧化（MAO）形成Al 2 O 3层，通过硝酸银和乙二醇合成AgNP。扫描电子显微镜，透射电子显微镜和傅里叶变换红外光谱分析APA涂层的形态和表征。通过动物实验和免疫组织化学进一步探索APA涂层的抗微生物活性，保温活性和生物相容性。结果：采用不同的颗粒尺寸和AgNP的浓度，成功制备了APA多功能膜。 Al 2 O 3层与SMA紧密结合并形成多孔表面，因此PLA和AgNPS层可以牢固地粘附到SMA上，从而减少SMA中镍离子的释放。 AGNPS涂覆优异的抗菌活性，有效地抑制金黄色葡萄球菌的生长。另外，与PLA和Al2O3的低导热率相结合，agnps紧密锚固在PLA的表面上，具有高红外反射率，使APA涂层获得良好的隔热性能。结论：我们已成功制备APA涂层并获得最佳AgNP，这使得它具有良好的保温性能，良好的抗菌活性和良好的生物相容性，为SMA的应用提供了一种新的前景。
展开▼
