Platelet adhesion and activation are key events in thrombus or clot formation on blood-contacting biomaterials. Thus understanding the complex interactions between biomaterial surface properties and platelets is important for developing vascular access devices that limit thromboembolic events. Medical-grade poly(urethanes) are frequently used in blood-contacting medical devices due to their desirable mechanical properties and high level of hemocompatibility. Moreover, it has been shown that sub-platelet-sized micropatterns reduce platelet adhesion. Based on this evidence, we hypothesized that bio-inspired, antifouling Sharklet™ (SK) microtopographies replicated in biomedical thermoplastic poly(urethane) (TPU) reduce both platelet adhesion and activation compared to smooth (SM) controls.

Hot embossing biomedical TPU produced micropatterned and SM controls with identical surface chemistries to facilitate the evaluation of the influence of surface microtopography on platelet adhesion and activation. SK microtopographies reduced platelet adhesion by 86%, p=0.007 compared to SM controls. Similarly, platelet activation as measured by average individual platelet area was reduced significantly (68%, p=0.002) on the SK pattern compared to SM. Here, we demonstrate that the application of engineered surface microtopographies to blood-contacting medical devices such as CVCs could further improve blood-biomaterial interactions and thus hemocompatibility without the application of anticoagulant coatings. Incorporating this technology into medical devices could also improve patient safety by reducing in-hospital morbidity, mortality and treatment costs.

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