Publications

Glial cell adhesion and protein adsorption on SAM coated semiconductor and glass surfaces of a microfluidic structure

Sasaki, Darryl Y.; Cox, Jimmy D.; Follstaedt, Susan C.; Curry, Mark S.; Skirboll, Steven K.; Gourley, Paul L.

The development of microsystems that merge biological materials with microfabricated structures is highly dependent on the successful interfacial interactions between these innately incompatible materials. Surface passivation of semiconductor and glass surfaces with thin organic films can attenuate the adhesion of proteins and cells that lead to biofilm formation and biofouling of fluidic structures. We have examined the adhesion of glial cells and serum albumin proteins to microfabricated glass and semiconductor surfaces coated with self-assembled monolayers (SAM) of octadecyltrimethoxysilane (OTMS) and N-(triethoxysilylpropyl)-O-polyethylene oxide urethane (TESP), to evaluate the biocompatibility and surface passivation those coatings provide. These films were exposed to solutions containing serum albumin proteins (4 mg/mL), glial cells in culturing media, and glial cells under fluid flow. While the OTMS surface resisted cell spreading and growth under culture conditions, the same surface induced biofouling in a cell flow experiment with a microfluidic structure. Interestingly, the TESP surface, which was supportive of cell adhesion and proliferation under cell culturing conditions, effectively passivated the microfluidic structure to cell adhesion and biofouling. The results suggest that the cell adhesion process is not only dependent on the chemistry of the surface but also on the time allotted to the cell to probe the surface.