This paper proposes a shape-memory balloon (SMB) to improve bone cement injection efficiency and postoperative thermo/chemotherapy for bone tumors. The SMB consists of biodegradable poly(ε-caprolactone) (PCL), an anticancer drug (doxorubicin, DOX), and heat-generating magnetic nanoparticles (MNPs). The balloon shape is fabricated in a mold by crosslinking PCL macromonomers with DOX and MNPs. The mechanical properties and shape-transition temperature (approximately 40 °C) of the SMB are modulated by adjusting the molecular weight of PCL and the crosslinking density. This allows safe inflation at the affected site with a 400% expansion rate by simple blow molding. The expanded shape is temporarily memorized at 37 °C, and the computed tomography image shows that the bone cement is successfully injected without extra pressure or leakage. The SMB releases DOX for over 4 weeks, allowing a prolonged effect at the local site. The local dosing is constant as the medication is continuously released, demonstrating an ON–OFF switchable heating/cooling response to alternating magnetic field irradiation. In vitro cytotoxic studies have demonstrated that heat generation/drug release and only drug release from the balloon kill approximately 99% and 60% of human osteosarcoma cells, respectively. The proposed SMB is promising in postoperative local thermo/chemotherapy for bone tumors.

中文翻译：

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形状记忆球囊提供同步热疗/化疗以提高抗骨肉瘤疗效

本文提出了一种形状记忆球囊 (SMB)，以提高骨水泥注射效率和骨肿瘤术后热/化疗。SMB 由可生物降解的聚（ε-己内酯）（PCL）、抗癌药物（多柔比星、DOX）和发热磁性纳米粒子（MNP）组成。通过将 PCL 大分子单体与 DOX 和 MNP 交联，在模具中制造气球形状。SMB 的机械性能和形状转变温度（约 40 °C）通过调节 PCL 的分子量和交联密度来调节。通过简单的吹塑成型，这可以在受影响的部位以 400% 的膨胀率进行安全充气。扩张后的形状在 37 °C 下暂时记忆，计算机断层扫描图像显示骨水泥成功注入，没有额外的压力或泄漏。SMB 释放 DOX 超过 4 周，允许在本地站点产生长期影响。随着药物的连续释放，局部剂量是恒定的，这表明对交变磁场照射的开-关可切换加热/冷却响应。体外细胞毒性研究表明，产热/药物释放和仅从球囊释放药物可分别杀死约 99% 和 60% 的人骨肉瘤细胞。拟议的 SMB 在骨肿瘤的术后局部热/化学疗法中很有前景。