School of Petrochemical Engineering, Liaoning Petrochemical University, Fushun 113001, China.
College of Engineering, Shenyang Agricultural University, Shenyang 110866, China.
Molecules. 2024 Sep 21;29(18):4481. doi: 10.3390/molecules29184481.
Poly(-isopropylacrylamide) (PNIPAM) offers a promising platform for non-invasive and gentle cell detachment. However, conventional PNIPAM-based substrates often suffer from limitations including limited stability and reduced reusability, which hinder their widespread adoption in biomedical applications. In this study, PNIPAM copolymer films were formed on the surfaces of glass slides or silicon wafers using a two-step film-forming method involving coating and grafting. Subsequently, a comprehensive analysis of the films' surface wettability, topography, and thickness was conducted using a variety of techniques, including contact angle analysis, atomic force microscopy (AFM), and ellipsometric measurements. Bone marrow mesenchymal stem cells (BMMSCs) were then seeded onto PNIPAM copolymer films prepared from different copolymer solution concentrations, ranging from 0.2 to 10 mg·mL, to select the optimal culture substrate that allowed for good cell growth at 37 °C and effective cell detachment through temperature reduction. Furthermore, the stability and reusability of the optimal copolymer films were assessed. Finally, AFM and X-ray photoelectron spectroscopy (XPS) were employed to examine the surface morphology and elemental composition of the copolymer films after two rounds of BMMSC adhesion and detachment. The findings revealed that the surface properties and overall characteristics of PNIPAM copolymer films varied significantly with the solution concentration. Based on the selection criteria, the copolymer films derived from 1 mg·mL solution were identified as the optimal culture substrates for BMMSCs. After two rounds of cellular adhesion and detachment, some proteins remained on the film surfaces, acting as a foundation for subsequent cellular re-adhesion and growth, thereby implicitly corroborating the practicability and reusability of the copolymer films. This study not only introduces a stable and efficient platform for stem cell culture and harvesting but also represents a significant advance in the fabrication of smart materials tailored for biomedical applications.
聚（异丙基丙烯酰胺）（PNIPAM）为非侵入性和温和的细胞分离提供了一个有前途的平台。然而，传统的基于 PNIPAM 的基底通常存在稳定性有限和可重复使用性降低等限制，这阻碍了它们在生物医学应用中的广泛采用。在这项研究中，使用涉及涂覆和接枝的两步成膜方法在玻璃载玻片或硅片表面上形成 PNIPAM 共聚物膜。随后，使用多种技术对膜的表面润湿性、形貌和厚度进行了全面分析，包括接触角分析、原子力显微镜（AFM）和椭偏测量。然后，将骨髓间充质干细胞（BMMSCs）接种到不同共聚物溶液浓度（0.2 至 10mg·mL）制备的 PNIPAM 共聚物膜上，以选择最佳的培养基底，该基底允许在 37°C 下良好地细胞生长，并通过降低温度有效地细胞分离。此外，评估了最佳共聚物膜的稳定性和可重复使用性。最后，使用原子力显微镜（AFM）和 X 射线光电子能谱（XPS）检查两轮 BMMSC 粘附和分离后共聚物膜的表面形态和元素组成。结果表明，PNIPAM 共聚物膜的表面性质和整体特性随溶液浓度显著变化。根据选择标准，确定来自 1mg·mL 溶液的共聚物膜为 BMMSCs 的最佳培养基底。在两轮细胞粘附和分离后，一些蛋白质仍然留在膜表面上，作为随后细胞再粘附和生长的基础，从而隐含地证实了共聚物膜的实用性和可重复使用性。这项研究不仅为干细胞培养和收获提供了一个稳定高效的平台，而且代表了为生物医学应用定制的智能材料制造的重要进展。
