Abstract text (incl. figure legends and references)
Platelets tend to be activated immediately when contacting any non-physiological surfaces. The development of anti-platelet adhesion/activation surfaces is important for platelet storage bags/tubing and many blood-contacting devices. Chemical modification can tune the response of cells to contacting surfaces but requires a long process involving many regulatory challenges to transfer into a marketable product. Biophysical modification refers to varying surface topography, elasticity, or porosity, and thus, can overcome those limitations. We developed hydrogels and nanostructured surfaces of different shapes to minimize platelet adhesion/activation. Further, we integrated functional molecules into these surfaces to enhance the surface function. The glass was modified with biomaterials including collagen, laminin, agarose, fibronectin, and poly-L-lysine (Fig. 1A)1,2 while nanostructured surfaces (Fig. 1B)3-5 were fabricated using a mask-free nanoprinting fluid force microscope. Atomic force microscopy, contact angle, confocal laser microscopy, and scanning electron microscopy were used to characterize the surfaces including stiffness, wettability, platelet-surface adhesion force, nanostructures, and platelet-surface response. Agarose was identified as the most stable surface and exhibited the strongest anti-platelet adhesion properties.2 Interestingly, integration into agarose iron oxide nanoparticles that carry antibacterial characteristics did not enhance platelet activation2 but caused bacterial death. Groove, hive, and grid nanostructured surfaces exhibited strong anti-platelet adhesion properties, especially the hive features.3,4 After UV-cure, the integrated biomolecules (rhodamine or biotin) in the nanostructures conserved their functions.5 Our findings contribute to the development of better anti-platelet adhesion/activation and anti-bacterial surfaces for blood-contacting devices.