Micropattern array with gradient size (µPAGS) plastic surfaces fabricated by PDMS (polydimethylsiloxane) mold-based hot embossing technique for investigation of cell-surface interaction.
Recently, it was found that the variations of physical environment significantly affect cell behaviors including cell proliferation, migration and differentiation. Through a plastic surface with controlled mechanical properties such as stiffness, one can change the orientation and migration of cells in a particular direction, thereby determining cell behaviors. In this study, we demonstrate a polydimethylsiloxane (PDMS) mold-based hot embossing technique for rapid, simple and low-cost replication of polystyrene (PS) surfaces having micropatterns. The PDMS mold was fabricated by UV-photolithography followed by PDMS casting; the elastomeric properties of PDMS enabled us to obtain conformal contact of the PDMS mold to a PS surface and to create high transcription quality of micropatterns on the PS surface. Two different types of circular micropillar and microwell arrays were successfully replicated on the PS surfaces based on the suggested technique. The micropatterns were designed to have various diameters (2-150 µm), spacings (2-160 µm) and heights (1.4, 2.4, 8.2 and 14.9 µm), so as to generate the gradient of physical properties on the surface. Experimental parametric studies indicated that (1) the embossing temperature became a critical processing parameter as the aspect ratio of micropattern increased and (2) the PDMS mold-based hot embossing could successfully replicate micropatterns, even having an aspect ratio of 2.7 for micropattern diameter of 6 µm, with an optimal processing condition (embossing pressure and temperature of 0.4 MPa and 130 °C, respectively) in this study. We carried out cell experiments with adipose-derived stem cells on the replicated PS surface with the height of 1.4 µm to investigate cellular behaviors in response to the micropattern array with gradient size. Cellular experiment results showed that the micropillar-arrayed surface improved cell proliferation as compared with the microwell-arrayed surface. We could also estimate the ranges of pattern sizes having the desired effects on the cellular behaviors.
Department of Mechanical Engineering, Pohang University of Science and Technology (POSTECH), Korea.
Min Jin
MJ
Choi
Ju Young
JY
Park
Kyoung Je
KJ
Cha
Jong-Won
JW
Rhie
Dong-Woo
DW
Cho
Dong Sung
DS
Kim
D000818:Animals; D001709:Biotechnology / Q000295:instrumentation*; D018929:Cell Culture Techniques / Q000295:instrumentation* / Q000379:methods*; D002454:Cell Differentiation / Q000502:physiology; D048708:Cell Growth Processes / Q000502:physiology; D002478:Cells, Cultured; D004129:Dimethylpolysiloxanes / Q000737:chemistry*; D006358:Hot Temperature; D008856:Microscopy, Fluorescence; D055616:Microtechnology / Q000295:instrumentation*; D010012:Osteogenesis; D011137:Polystyrenes / Q000737:chemistry; D011312:Pressure; D013234:Stem Cells; D013499:Surface Properties; D054457:Tissue Scaffolds
D004129:Dimethylpolysiloxanes; D011137:Polystyrenes; C013830:baysilon