药物传递策略旨在通过增加靶向部位的药物浓度并使药物不会传递到非靶标组织，从而最大化药物的治疗效能。人们对使用磁性纳米颗粒结合施加的磁场来选择性地控制药物在目标组织中的积累和释放以及最小化对其他组织的影响非常感兴趣。本研究通过溶剂蒸发法将疏水性阿霉素（DOX，模拟药物）和疏水性油酸超顺磁性纳米颗粒（SPION-OA）封装到水性聚脲纳米胶囊（CPUM）的疏水核心中，制备了基于水性聚脲纳米胶囊的磁靶向药物传递系统。制备的药物载荷磁纳米胶囊（CPUM-DOX-SPION）呈球形，平均直径约为158 nm。磁纳米胶囊在体外表现出超顺磁性，具有优异的磁共振成像（MRI）对比效应和T2弛豫。通过MTT检测和流式细胞术评估样品在不存在和存在磁场下的细胞相容性和细胞摄取，并利用共聚焦显微镜对细胞进行成像。磁场的应用增加了细胞毒性和细胞摄取，同时改善了DOX的传递。此外，肿瘤体积的体内研究显示，在外部磁场的存在下，使用CPUM-DOX-SPION处理的小鼠组与在无磁场下使用相同的磁纳米胶囊和相同剂量的游离DOX处理的小鼠组相比，肿瘤生长明显受到抑制，而体重无明显损失。此外，体内MRI实验显示了这些磁纳米胶囊作为MRI诊断探针的潜力，结果表明磁导引的CPUM-SPION磁纳米胶囊传递到肿瘤中能够显著提高靶向效果。所有结果表明，制备的新型磁纳米胶囊将是有效的磁导引化疗药物传递和图像引导个体化医学的有前景的治疗系统。版权所有©2023 Elsevier B.V.保留所有权利。

Drug delivery strategies aim to maximize a drug's therapeutic efficiency by increasing the drug's concentration at the target site while minimizing delivery to off-target tissues. There is a great deal of interest in using magnetic nanoparticles in combination with applied magnetic fields to selectively control drug accumulation and release in target tissue while minimizing effects on other tissues. In this study, a magnetic targeted drug delivery system based on waterborne polyurethane nanomicelles was prepared by encapsulating hydrophobic doxorubicin (DOX, model drug) and hydrophobic oleic acid-superparamagnetic nanoparticles (SPION-OA) into the hydrophobic core of waterborne polyurethane micelles (CPUM) using the solvent evaporation method. The prepared drug-loaded magnetomicelles (CPUM-DOX-SPION) had a spherical shape with an average diameter of 158 nm. The magnetomicelles showed superparamagnetic properties with excellent magnetic resonance imaging (MRI) contrast effects and T2 relaxation in vitro. In the absence and presence of a magnetic field, the cytocompatibility and cellular uptake of the samples were assessed by MTT assay and flow cytometry, respectively, and the cells were imaged with a confocal microscope. Application of the magnetic field increased cellular cytotoxicity and cellular uptake in association with improved DOX delivery. In addition, the in vivo study of tumor volume showed that tumor growth of the mice group treated with CPUM-DOX-SPION in the presence of an external magnetic field was significantly retarded, with no apparent loss of body weight, compared with the same magnetomicelles in the absence of the magnetic field and with free DOX at the same dose. Moreover, the in vivo MRI experiment indicated the potential of these magnetomicelles as a probe in MRI diagnosis for tumor targeting, and the results showed that magnetically guided delivery of CPUM-SPION magnetomicelles into tumors could significantly improve the targeting efficacy. All the results suggest that the prepared novel magnetomicelles will be promising theranostic systems for effective magnetically guided delivery of chemotherapeutic agents and image-guided personalized medicine.Copyright © 2023 Elsevier B.V. All rights reserved.