Introduction: Polyimide (PI) exhibits good biocompatibility and high mechanical strength, but biological inertness that does not stimulate bone regeneration, while laponite possesses excellent bioactivity.
Methods: In this study, to improve the bioactivity of PI, nano–laponite ceramic (LC)–PI composites (LPCs) were fabricated by melt processing as implantable materials for bone repair.
Results: The compressive strength, hydrophilicity, and surface roughness of LPCs with 40 w% LC content (LPC40s) were higher than LPC20s, and LPC20s higher than pure PI. In addition, no apatite mineralization occurred on PI, while apatite mineralized on LPCs in simulated body fluid. Compared with LPC20, more apatite deposited on LPC40, indicating good bioactivity. Moreover, the adhesion, proliferation, and alkaline phosphatase activity of rat bone mesenchymal stem cells on LPCs significantly increased with LC content increasing in vitro. Furthermore, the evaluations of animal experiments (micro-CT, histology, and pushout load) revealed that compared with LPC20 and PI, LPC40 significantly enhanced osteogenesis and osseointegration in vivo.
Discussion: Incorporation of LC into PI obviously improved not only surface physicochemical properties but also biological properties of LPCs. LPC40 with high LC content displayed good biocompatibility and bioactivity, which markedly promoted osteogenesis and osseointegration. Therefore, with its superior biocompatibility and bioactivity, LPC40 could be an alternative candidate as an implant for orthopedic applications.

Keywords: laponite, polyimide, cytocompatibility, bone repair


中文翻译：

---

纳米锂皂石陶瓷对聚酰亚胺基生物复合材料的表面性能、磷灰石矿化、细胞反应和骨整合的影响

简介：聚酰亚胺（PI）具有良好的生物相容性和较高的机械强度，但具有生物惰性，不刺激骨再生，而锂皂石具有优异的生物活性。
方法：在本研究中，为提高 PI 的生物活性，通过熔融加工制备纳米锂皂石陶瓷 (LC)-PI 复合材料 (LPCs) 作为骨修复的可植入材料。
结果：LC含量为40 w%的LPCs（LPC40s）的抗压强度、亲水性和表面粗糙度均高于LPC20s，LPC20s高于纯PI。此外，PI上没有磷灰石矿化，而模拟体液中的LPC上磷灰石矿化。与LPC20相比，LPC40上沉积的磷灰石较多，表明其具有良好的生物活性。此外，大鼠骨间充质干细胞在 LPCs 上的粘附、增殖和碱性磷酸酶活性随着 LC 含量的增加而显着增加。此外，动物实验（微 CT、组织学和推出负荷）的评估表明，与 LPC20 和 PI 相比，LPC40 显着增强了体内成骨和骨整合。
讨论：将LC掺入PI中不仅明显改善了LPC的表面理化性质，而且还改善了LPC的生物学性质。高LC含量的LPC40表现出良好的生物相容性和生物活性，显着促进成骨和骨整合。因此，凭借其卓越的生物相容性和生物活性，LPC40 可以作为骨科应用植入物的替代候选者。

关键词：锂皂石，聚酰亚胺，细胞相容性，骨修复