A precision technology for controlling protein adsorption and cell adhesion in bioMEMS

A surface coating technique is investigated to enhance device biocompatibility by eliminating bio-fouling, the strong but non-specific affinity of proteins and cells to attach to surfaces. This coating is a conformal, thin poly(ethylene glycol)-like film deposited in a glow discharge of tetraglyme. Substrates with different chemistries are successfully modified, and exhibit ultralow protein adsorption and cell attachment with the coating. This "stealth" or "non-fouling" coating can also be faithfully patterned using standard photolithography processes. The interaction of proteins and cells with patterned surfaces is limited only to the protein-adhesive domains, thus creating heterogeneous patterns of proteins and cell cultures on the surface. The potential benefits of our technique to applications such as cell-based assays and micro-electrodes are discussed.