Micropatterned Smart Culture Surfaces via Multi-Step Physical Coating of Functional Block Copolymers for Harvesting Cell Sheets with Controlled Sizes and Shapes

Cell micropatterning on micropatterned thermoresponsive polymer-based culture surfaces facilitates the creation of on-demand and functional cell sheets. However, the fabrication of micropatterned surfaces generally includes complicated procedures with multi-step chemical reactions. To overcome this issue, this study proposes a facile preparation of micropatterned thermoresponsive surfaces via a two-step physical coating of two different diblock copolymers. Both copolymers contain poly(butyl methacrylate) blocks as hydrophobic anchors for water-stable polymer deposition. At first, thermoresponsive polymer layers are constructed on cell culture dishes via spin-coating block copolymers containing poly(N-isopropylacrylamide) blocks that exhibit a transition temperature of approximate to 30 degrees C in aqueous media. To create polymer micropatterns on the thermoresponsive surfaces, microcontact printing of block copolymers containing hydrophilic poly(N-acryloylmorpholine) (PNAM) blocks is performed using polydimethylsiloxane stamps. Stamped PNAM-based block polymers are adsorbed to the outermost thermoresponsive surfaces, and increase the surface hydrophilicity with decreasing protein adsorption. Cells adhere and proliferate on the thermoresponsive domains at 37 degrees C, whereas the stamped hydrophilic domains remain cell-repellent for 7 days. At 20 degrees C, cell sheets with controlled sizes and shapes are harvested from the surfaces with the desired micropatterns. This technique is useful for the preparation of micropatterned polymer surfaces for various biomedical applications.

Automated summary

This study proposes a facile preparation method of micropatterned thermoresponsive surfaces by physically coating two different diblock copolymers. The method involves constructing thermoresponsive polymer layers on cell culture dishes and creating polymer micropatterns using microcontact printing, providing a useful technique for various biomedical applications.