Spatially Controlled Cell Adhesion via Micropatterned Surface Modification of Poly(dimethylsiloxane)

Abstract

Spatial control of cell growth on surfaces can be achieved by the selective deposition of molecules that influence cell adhesion. The fabrication of such substrates often relies upon photolithography and requires complex surface chemistry to anchor adhesive and inhibitory molecules. The production of simple, cost-effective substrates for cell patterning would benefit numerous areas of bioanalytical research including tissue engineering and biosensor development. Poly(dimethylsiloxane) (PDMS) is routinely used as a biomedical implant material and as a substrate for microfluidic device fabrication; however, the low surface energy and hydrophobic nature of PDMS inhibits its bioactivity. We present a method for the surface modification of PDMS to promote localized cell adhesion and proliferation. Thin metal films are deposited onto PDMS through a physical mask in the presence of a gaseous plasma. This treatment generates topographical and chemical modifications of the polymer surface. Removal of the deposited metal exposes roughened PDMS regions enriched with hydrophilic oxygen-containing species. The morphology and chemical composition of the patterned substrates were assessed by optical and atomic force microscopies as well as X-ray photoelectron spectroscopy. We observed a direct correlation between the surface modification of PDMS and the micropatterned adhesion of fibroblast cells. This simple protocol generates inexpensive, single-component substrates capable of directing cell attachment and growth.

Surface modification of cobalt–chromium–tungsten–nickel alloy using octadecyltrichlorosilanes

“…For SAM/sp-Co-Cr, the peaks observed at [8]. In the literature, the BE of Si 2p peak at $102 eV was assigned to Si-O-Si cross-links [65][66][67][68][69] and the peak at $102.6 eV BE was assigned to Si-O-Metal linkages [65,69,70]. In our study, the BE of Si 2p was observed at 102.…”

Endothelial cell adhesion and growth within a bioassay chamber using microstamped ECM proteins

“…22 Our work confirms other findings where endothelial cells have been shown to be partially excluded from hydrophobic surfaces in favor of hydrophilic surfaces due to a reduced adhesion on hydrophobic surfaces. 8,25 Furthermore, others have shown a decrease in cell viability/density on hydrophobic glass, 8 which we also confirm. The resulting impact that we show on the degree of confluence of the cells was a 10-fold increase in confluence by only providing a hydrophilic vs. hydrophobic bare glass substrate both in culture and in the bioassay chamber.…”

“…The significantly higher cell density within the patterned regions is thus likely due to a combination of factors, including the probable inability for cells to adhere to hydrophobic surfaces. 22,25,26 Within the ECM stamped areas, the higher density could have been due to either an increase in initial endothelial cell attachment to ECM proteins, 6,19 although where cells initially land is partly due to statistical probably. Despite this, others have shown an increased ability to direct cells onto patterned collagen IV onto hydrophobic glass coverslips because the cells had an increased ability to initiate attachment to collagen IV.…”

Patterned PDMS based cell array system: a novel method for fast cell array fabrication

“…Due to the low surface energy and hydrophobicity, PDMS surfaces inhibit cell adhesion (Patrito et al 2007). However, a good adhesion is obtained between PDMS and polished surfaces like tissue culture polystyrene plate (TCPS) and glass (Lotters et al 1997).…”