In contemporary society, a large percentage of medical equipment coming in contact with blood is manufactured from plastic polymers. Unfortunately, exposure may result in undesirable protein-material interactions that can potentially trigger deleterious biological processes such as thrombosis. To address this problem, we have developed an ultrathin antithrombogenic coating based on monoethylene glycol silane surface chemistry. The strategy is exemplified with polycarbonate-a plastic polymer increasingly employed in the biomedical industry. The various straightforward steps of surface modification were characterized with X-ray photoelectron spectroscopy supplemented by contact angle goniometry. Antithrombogenicity was assessed after 5 min exposure to whole human blood dispensed at a shear rate of 1000 s(-1). Remarkably, platelet adhesion, aggregation, and thrombus formation on the coated surface was greatly inhibited (>97% decrease in surface coverage) compared to the bare substrate and, most importantly, nearly nonexistent.