Sub-micron texturing for reducing platelet adhesion to polyurethane biomaterials

• Published in: Journal of biomedical materials research 2006-03, Vol.76A (3), p.561-570
• Main Authors: Milner, Keith R., Snyder, Alan J., Siedlecki, Christopher A.
• Format: Article
• Language: English
• Subjects: Animals; Biocompatible Materials - chemistry; Blood Platelets - physiology; Blood Platelets - ultrastructure; Cattle; Materials Testing - methods; microfabrication; Microscopy, Electron, Scanning; platelet adhesion; Platelet Adhesiveness - physiology; polyurethane; Polyurethanes - chemistry; Surface Properties; texture
• ISSN: 1549-3296; 0021-9304; 1552-4965; 1097-4636
• DOI: 10.1002/jbm.a.30554

Platelet adhesion is a key event in thrombus development on blood‐contacting medical devices. It has been demonstrated that changes to the chemistry of a material surface can reduce platelet adhesion. In this work, it is hypothesized that sub‐micron surface textures may also reduce adhesion via a decrease in the surface area of material with which platelets can make contact, and hence a decreased probability of interaction with adhesive ligands. A polyether(urethane urea) was textured with two different sizes of sub‐micron pillars using a replication molding technique that did not alter the material surface chemistry. Adhesion of platelets was assessed in a physiologically relevant shear stress range of 0–67 dyn/cm2 using a rotating disk system. Platelets were immunofluorescently labeled and adhesion was compared on smooth and textured samples. Platelet adhesion was greatest at low shear stress ranging from 0 to 5 dyn/cm2, and sub‐micron textures were observed to reduce platelet adhesion in this range. Additionally, non‐adherent platelets did not demonstrate large‐scale activation after exposure to textured samples. We conclude that surface textures with sub‐platelet dimensions may reduce platelet adhesion from plasma to polyether(urethane urea) at low shear stress. © 2005 Wiley Periodicals, Inc. J Biomed Mater Res, 2006