Publication details

Authors: Liu, L.; Koo, Y.; Collins, B.; Xu, Z.; Sankar, J.; Yun, Y. 
Title: Biodegradability and platelets adhesion assessment of magnesium-based alloys using a microfluidic system 
Type: Journal Article 
Publisher: PLoS One 
Year: 2017 
Volume: 12 
Start Page: e0182914 
End Page:  
DOI: 10.1371/journal.pone.0182914 
Abstract: Magnesium (Mg)-based stents are extensively explored to alleviate atherosclerosis due to their biodegradability and relative hemocompatibility. To ensure the quality, safety and cost-efficacy of bioresorbable scaffolds and full utilization of the material tunability afforded by alloying, it is critical to access degradability and thrombosis potential of Mg-based alloys using improved in vitro models that mimic as closely as possible the in vivo microenvironment. In this study, we investigated biodegradation and initial thrombogenic behavior of Mg-based alloys at the interface between Mg alloys' surface and simulated physiological environment using a microfluidic system. The degradation properties of Mg-based alloys WE43, AZ31, ZWEK-L, and ZWEK-C were evaluated in complete culture medium and their thrombosis potentials in platelet rich plasma, respectively. The results show that 1) physiological shear stress increased the corrosion rate and decreased platelets adhesion rate as compared to static immersion; 2) secondary phases and impurities in material composition induced galvanic corrosion, resulting in higher corrosion resistance and platelet adhesion rate; 3) Mg-based alloys with higher corrosion rate showed higher platelets adhesion rate. We conclude that a microfluidic-based in vitro system allows evaluation of biodegradation behaviors and platelets responses of Mg-based alloys under specific shear stress, and degradability is related to platelets adhesion. 
Keywords: Alloys/*adverse effects/chemistry, Biocompatible Materials/*adverse effects/chemistry, Blood Platelets/cytology/drug effects, Corrosion, Equipment Design, Humans, Magnesium/*adverse effects/chemistry, Materials Testing/*instrumentation, Microfluidic Analytical Techniques/*instrumentation, *Platelet Adhesiveness/drug effects, Surface Properties, Thrombosis/*etiology