Prevention of Thrombogenesis from Whole Human Blood on Plastic Polymer by Ultrathin Monoethylene Glycol Silane Adlayer

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

Adlayer-Mediated Antibody Immobilization to Stainless Steel for Potential Application to Endothelial Progenitor Cell Capture

This work describes the straightforward surface modification of 316L stainless steel with BTS, <i>S</i>-(11-trichlorosilylundecanyl)-benzene­thiosulfonate, a thiol-reactive trichlorosilane cross-linker molecule designed to form intermediary coatings with subsequent biofunctionalization capability. The strategy is more specifically exemplified with the immobilization of intact antibodies and their Fab′ fragments. Both surface derivatization steps are thoroughly characterized by means of X-ray photoelectron spectroscopy. The antigen binding capability of both types of biofunctionalized surfaces is subsequently assessed by fluorescence microscopy. It was determined that BTS adlayers achieve robust immobilization of both intact and fragmented antibodies, while preserving antigen binding activity. Another key finding was the observation that the Fab′ fragment immobilization strategy would constitute a preferential option over that involving intact antibodies in the context of <i>in vivo</i> capture of endothelial progenitor cells in stent applications