Ligand capture and activation of human platelets at monolayer modified gold surfaces

摘要: Blood platelet adhesion is crucial in dictating haemocompatibility of medical implants and capture diagnostics. Understanding the role activation at chemically modified interfaces important but relatively unexplored. Using scanning electron microscopy confocal fluorescence a quantitative assessment blood platelets self-assembled monolayers mixed (SAMs) on gold as function status was conducted. Single were prepared using thiol-functionalized arginine-glycine-aspartic acid (RGD), C-Ahx-GRGDS (Ahx = aminohexanoic linker), thiolated poly(ethylene)glycol (PEG-COOH) 1-octanethiol. When incubated with suspensions resting platelets, RGD promoted compared to bare or alkanethiol gold. Increasing ratio deposition solution decreased extent adhesion. Platelet increased approximately 3 fold PEG-COO- surfaces RGD-alone. Platelets adhered RGD : alkane SAM found be captured their state. In contrast, activated by these substrates. The effect treating chemical activators, Mn2+ DTT physiological activator, thrombin, efficiency also investigated. treated presented similar untreated while surprisingly yielded very significant decrease And, any that captured, Thrombin efficiencies platelets. However, fully activated. distinction between physiologically interesting likely originate from differences conformation integrin induced each process. Finally, surface could reversed incubation linear cyclical for PEGCOO- respectively. specificity removal confirmed occurring through integrin–RGD interactions.