College of Polymer Science and Engineering, State Key Laboratory of Polymer Materials Engineering, Sichuan University, Chengdu 610065, P. R. China.
J Biomater Sci Polym Ed. 2010;21(12):1637-52. doi: 10.1163/092050609X12525750021270. Epub 2010 Jun 9.
In this study, a series of 3-D interconnected porous scaffolds with various pore diameters and porosities was fabricated by freeze-drying with non-toxic biodegradable waterborne polyurethane (WBPU) emulsions of different concentration. The structures of these porous scaffolds were characterized by scanning electron microscopy (SEM), and the pore diameters were calculated using CIAS 3.0 software. The pores obtained were 3-D interconnected in the scaffolds. The scaffolds obtained at different pre-freeze temperatures showed a pore diameter ranging from 2.8 to 99.9 microm with a pre-freezing temperature of -60 degrees C and from 13.1 to 229.1 microm with a pre-freezing temperature of -25 degrees C. The scaffolds fabricated with WBPU emulsions of different concentration at the same pre-freezing temperature (-25 degrees C) had pores with mean pore diameter between 90.8 and 39.6 microm and porosity between 92.0 and 80.0%, depending on the emulsion concentration. The effect of porous structure of the scaffolds on adhesion and proliferation of human umbilical vein endothelial cells (HUVECs) cultured in vitro was evaluated using the MTT assay and environmental scanning electron microscopy (ESEM). It was found that the better adhesion and proliferation of HUVECs on 3-D scaffolds of WBPU with relative smaller pore diameter and lower porosity than those on scaffolds with larger pore and higher porosity and film. Our work suggests that fabricating a scaffold with controllable pore diameter and porosity could be a good method to be used in tissue-engineering applications to obtain carriers for cell culture in vitro.
在这项研究中，通过使用不同浓度的无毒可生物降解水性聚氨酯（WBPU）乳液进行冷冻干燥，制备了一系列具有不同孔径和孔隙率的 3D 互连通孔支架。通过扫描电子显微镜（SEM）对这些多孔支架的结构进行了表征，并使用 CIAS 3.0 软件计算了孔径。所得的孔是支架中的 3D 互连通的。在不同的预冻温度下获得的支架，在预冻温度为-60°C 时，孔径范围为 2.8 至 99.9 微米，在预冻温度为-25°C 时，孔径范围为 13.1 至 229.1 微米。在相同的预冻温度（-25°C）下，使用不同浓度的 WBPU 乳液制备的支架具有 90.8 至 39.6 微米之间的平均孔径和 92.0 至 80.0%之间的孔隙率，这取决于乳液的浓度。通过 MTT 测定法和环境扫描电子显微镜（ESEM）评估了支架的多孔结构对体外培养的人脐静脉内皮细胞（HUVEC）的粘附和增殖的影响。结果发现，与具有较大孔径和较高孔隙率的支架相比，具有相对较小孔径和较低孔隙率的 WBPU 3D 支架上 HUVEC 的粘附和增殖更好。我们的工作表明，制备具有可控制的孔径和孔隙率的支架可能是一种很好的方法，可用于组织工程应用，以获得体外细胞培养的载体。
