Tuning Polydimethylsiloxane (PDMS) properties for biomedical applications

¹Applied Research & Innovation, Nova Scotia Community College, Ivany Campus, Dartmouth, NS, B2Y 0A5, Canada

²Ivan Curry School of Engineering, Acadia University, Wolfville, NS, B4P 2R6, Canada

³PennState College of Engineering, Pennsylvania State University, University Park, PA 16802, USA

Adv. Mater. Lett., 2019, 10 (2), pp 107-111

DOI: 10.5185/amlett.2019.2130

Publication Date (Web): Dec 19, 2018

Copyright © IAAM-VBRI Press

E-mail: etienne.mfoumou@nscc.ca

Abstract

Polydimethylsiloxane (PDMS) is used extensively to study cell-substrate interactions because its mechanical properties are easily tuned in physiologically relevant ranges. These changes in mechanical properties are also known to modulate surface chemistry and cell response. In this study, PDMS pre-polymer was combined with increasing amounts of cross-linker (3.3, 5.0, 10.0, 12.5, 20.0 and 33.3 wt.%). The solutions were mixed in sterile conditions and degassed, then poured into 60 mm cell culture dishes to a depth of 1 mm. This was followed by curing at a constant temperature of 75 ^oC for 2 hours. The PDMS substrates were then exposed to an air plasma for 10 minutes. All substrates were exposed to UV light for further sterilization and understanding of the structure/morphology of the substrates was obtained with microscopic techniques. A SH-SY5Y neuroblastoma cell line was used in cell culture experiment. Cells were plated at a concentration of 300 x 10⁶ cells/dish on plasma treated PDMS substrates and incubated at 37 ^oC in a humidified 5 % CO₂ environment. For the assessment of morphological changes, images of cells growing on each substrate were captured using an inverted phase contrast microscope. Cell adhesion as well as immunofluorescence analyses were conducted, and the mechanical as well as surface properties of PDMS were correlated to neuroblastoma cell behaviour. The results reveal that the physicality of the extracellular matrix/environment (ECM) substrate governs cell behavior regardless of hormones, cytokines, or other soluble regulatory factors. The approach used in this study may open up new avenues in translational medicine and pharmacodynamics research. 

Keywords

Polydimethylsiloxane, cell-substrate interactions, cell culture, cell transdifferentiation, mechanical and surface properties.