[Preparation of microarray-structured polymer film and its effect on 3D cell culture]

The two-dimensional (2D) cell culture model is currently used to study cellular processes and drug screening for human diseases. However, the growth of cells is affected by many factors. For conventional 2D cell culture, many of the difficulties are encountered in accurately replicating the cell function in three-dimensional (3D) tissues. Compared with 2D cell culture, much attention is paid to the cell-to-cell and cell-matrix interactions for 3D cell culture systems, which can more closely mimic the growth environment for cultured cells. Therefore, the 3D cell culture system was more suitable for a variety of applications such as drug screening and cell proliferation. In this work, we prepared microarray-structured polymer films with different geometric structures by nanoimprint lithography and used the films as cell culture platforms for the culture of 293T cells. Through the adjustment of the surface morphology and water contact angle of the prepared films, the regulation of the morphological changes of cell growth was successfully realized. Experimental results demonstrated that the hydrophilic films with 10 μm-pillar microstructure are applicable to 3D cell culture, whereas the hydrophobic films with 3 μm-pillar microstructure are only suitable for 3D culture of cells with a smaller size and stiff cuticular layer. In addition, cells tended to the formation of spheroids on the hydrophobic films, while cells usually adhered to the surface and grew on the hydrophilic films. This work represents further technological progress in the development of 3D cell culture, thereby facilitating future studies of physiologically relevant processes.