Driving Cells with Light‐Controlled Topographies

Abstract

Cell–substrate interactions can modulate cellular behaviors in a variety of biological contexts, including development and disease. Light‐responsive materials have been recently proposed to engineer active substrates with programmable topographies directing cell adhesion, migration, and differentiation. However, current approaches are affected by either fabrication complexity, limitations in the extent of mechanical stimuli, lack of full spatio‐temporal control, or ease of use. Here, a platform exploiting light to plastically deform micropatterned polymeric substrates is presented. Topographic changes with remarkable relief depths in the micron range are induced in parallel, by illuminating the sample at once, without using raster scanners. In few tens of seconds, complex topographies are instructed on demand, with arbitrary spatial distributions over a wide range of spatial and temporal scales. Proof‐of‐concept data on breast cancer cells and normal kidney epithelial cells are presented. Both cell types adhere and proliferate on substrates without appreciable cell damage upon light‐induced substrate deformations. User‐provided mechanical stimulation aligns and guides cancer cells along the local deformation direction and constrains epithelial colony growth by biasing cell division orientation. This approach is easy to implement on general‐purpose optical microscopy systems and suitable for use in cell biology in a wide variety of applications.

Quantitative Study of Morphological Features of Stem Cells onto Photopatterned Azopolymer Films

“…For instance, studies have recently demonstrated that a biocompatible azopolymer can efficiently control the phenotype of neurons by influencing how cells respond to the nanometric grooves: i.e., by promoting a synaptic formation of multiple neurites or the elongation of single predominant neurites along preferential directions over time [40]. In the current scenario, complex topographies could be instructed on demand, under a controlled light stimulation, with arbitrary spatial distributions over a wide range of spatial and temporal scales [41]. In this perspective view, the route toward the design of bioinspired materials that are able to dynamically interact and/or instruct cells for innovative approaches in tumor diagnosis and in vivo cancer modeling can be traced.…”

Multifunctional Structured Platforms: From Patterning of Polymer-Based Films to Their Subsequent Filling with Various Nanomaterials

“…Generally, in order to transfer a pattern from the mold to polymeric films deposited on flexible [ 107 ], solid [ 108 ], or textile [ 3 ] substrates, molds are mechanically pressed against a polymer melt [ 109 ] or films while heating the latter to melting temperatures [ 110 , 111 ] ( Figure 5 a). For efficiency reasons, it is also possible to press the molds against films soaked with non-solvents to form surface “gels” [ 112 ], or against as drop-cast solutions [ 113 ] or even to poor solutions of interest directly on the mold [ 114 ] and heat afterwards.…”

“…There is a variety of structures that can be obtained with TNIL ( Table 2 ) and employed in different biological applications [ 111 , 113 , 114 , 119 , 120 ], organic photovoltaics [ 121 ], interfaces [ 122 ], superhydrophobic surfaces [ 107 ], memory elements [ 123 ], dental implants [ 124 ], etc. Miniaturized patterns obtained by TNIL and consisting in poly(benzyl methacrylate) (PBMA) lines/2D gratings and nanoholes were recently reported [ 87 ] ( Figure 6 a–b).…”

Functional Liquid Crystal Polymer Surfaces with Switchable Topographies

“…[ 17,25,115–118 ] Other applications of switchable surfaces include biomedical applications, such as regulating the cell adhesion, spreading, shaping, proliferation, migration, and differentiation. [ 15,119–122 ]…”