In the past decade, polymeric magnetic membranes have been used to investigate mechanical stimuli on adherent cells and cellular mechanotransduction. However, the homogeneity of these particles inside these membranes is often overlooked. In this study, magnetic polydimethylsiloxane (PDMS) membranes were prepared by using magnetite (Fe₃O₄) particles effectively dispersed inside PDMS for the assessment of possible cellular behavior changes. Magnetite particles were synthesized using the co-precipitation method. Magnetic-particle-embedded PDMS (mpPDMS) membranes were prepared by homogenizing magnetic particles with a PDMS elastomer before the curing process. The magnetization, molecular composition and mechanical properties of these mpPDMS membranes were analyzed by using vibrating-sample magnetometry, optical microscopy, Fourier transform infrared spectroscopy and rheometry. The biocompatibility, cell viability and morphology of human fetal osteoblast (hFOB) cells were evaluated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, alamarBlue cell proliferation assay and F-actin/4′,6-diamino-2-phenylindole staining. The results indicated that membranes fabricated using the presented methodology had increased magnetic particle homogeneity compared with those in previous studies and hFOB cells maintained their functionality on 0.5% (w/w) mpPDMS membranes. The methodology for the fabrication of mpPDMS reported here could be used in future studies for the investigation of cellular mechanotransduction pathways in a more controlled and repeatable manner on PDMS-based substrates.

中文翻译：

---

制备均质磁性 PDMS 膜以调节细胞行为

在过去的十年中，聚合物磁膜已被用于研究对贴壁细胞和细胞机械转导的机械刺激。然而，这些膜内这些颗粒的均匀性常常被忽视。在这项研究中，磁性聚二甲基硅氧烷 (PDMS) 膜是通过使用磁铁矿 (Fe ₃ O ₄) 粒子有效地分散在 PDMS 内，用于评估可能的细胞行为变化。使用共沉淀法合成磁铁矿颗粒。磁性粒子嵌入的 PDMS (mpPDMS) 膜是通过在固化过程之前用 PDMS 弹性体均质化磁性粒子来制备的。这些 mpPDMS 膜的磁化强度、分子组成和机械性能通过使用振动样品磁力测定法、光学显微镜、傅里叶变换红外光谱和流变仪进行了分析。通过 3-(4,5-二甲基噻唑-2-基)-2,5-二苯基四唑溴化试验、alamarBlue 细胞增殖试验和 F-actin/4 评估人胎儿成骨细胞 (hFOB) 的生物相容性、细胞活力和形态',6-diamino-2-phenylindole 染色。结果表明，与以前的研究相比，使用所提出的方法制造的膜具有更高的磁粉均匀性，并且 hFOB 细胞在 0.5% (w/w) mpPDMS 膜上保持其功能。此处报道的 mpPDMS 制造方法可用于未来的研究，以在基于 PDMS 的基材上以更可控和可重复的方式研究细胞机械转导途径。