Cell investigation into the biocompatibility of adult human dermal fibroblasts with PCL nanofibers/TiO2 nanotubes on the surface of Ti-30Ta alloy for biomedical applications.

The polymer poly(ε-caprolactone) (PCL) has been used in the biomaterial field for its relatively inexpensive price and suitability for modification. Also, its chemical and biological properties are desirable for biomedical applications. The electrospinning process has been used for producing polymer fibers of PCL due in large part to an increased interest in nanoscale properties and technologies. Moreover, the use of biocompatible polymers for the viability of cell growth is a promising alternative to improve osseointegration. Characterization techniques such as scanning electron microscopy and contact angle were used for analyses of samples. Adult human dermal fibroblasts (neonatal) were utilized to evaluate the biocompatibility of the association of the electrospinning process of the biocompatible polymer (PCL) with TiO2 nanotubes on the Ti-30Ta alloy surface. The results of this study showed a favorable response for adhesion on the surface. This promising material is due to the modulation of the biological response.

Hemocompatibility of hyaluronan enhanced linear low density polyethylene for blood contacting applications.

Despite their overall success, different blood-contacting medical devices such as heart valves, stents, and so forth, are still plagued with hemocompatibility issues which often result in the need for subsequent replacement and/or life-long anticoagulation therapy. Consequently, there is a significant interest in developing biomaterials that can address these issues. Polymeric-based materials have been proposed for use in many applications due to their ability to be finely tuned through manufacturing and surface modification to enhance hemocompatibility. In this study, we have developed a novel, hydrophilic biomaterial comprised of an interpenetrating polymer network (IPN) of hyaluronan (HA) and linear low density polyethylene (LLDPE). HA is a highly lubricous, anionic polysaccharide ubiquitously found in the human body. It is currently being investigated for a vast array of biomedical applications including cardiovascular therapies such as hydrogel-based regenerative cell therapies for myocardial infarction, HA-coated stents, and surface modifications of polyurethane and metals for use in blood-contacting implants. The aim of this study was to assess the in vitro thrombogenic response of the hydrophilic polymer surface, HA-LLDPE for future potential use as flexible heart valve leaflets. The results indicate that HA-LLDPE is non-toxic and reduces thromobogenicity as compared to LLDPE surfaces, asserting its feasibility for use as a blood-contacting biomaterial. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 106B: 1964-1975, 2018.

Glycocalyx-Inspired Nitric Oxide-Releasing Surfaces Reduce Platelet Adhesion and Activation on Titanium.

The endothelial glycocalyx lining the inside surfaces of blood vessels has multiple features that prevent inflammation, blood clot formation, and infection. This surface represents the highest standard in blood compatibility for long-term contact with blood under physiological flow rates. Engineering materials used in blood-contacting biomedical devices, including metals and polymers, have undesirable interactions with blood that lead to failure modes associated with inflammation, blood clotting, and infection. Platelet adhesion and activation are key events governing these undesirable interactions. In this work, we propose a new surface modification to titanium with three features inspired by the endothelial glcyocalyx: First, titanium surfaces are anodized to produce titania nanotubes with high surface area. Second, the nanostructured surfaces are coated with heparin-chitosan polyelectrolyte multilayers to provide glycosaminoglycan functionalization. Third, chitosan is modified with a nitric oxide-donor chemistry to provide an important antithrombotic small-molecule signal. We show that these surfaces are nontoxic with respect to platelets and leukocytes. The combination of glycocalyx-inspired features results in a dramatic reduction of platelet and leukocyte adhesion and platelet activation.