Blood Compatibility of ZrO₂ Particle Reinforced PEEK Coatings on Ti6Al4V Substrates.

Jian Song,Weiqiang Liu,Hongyu Shi,Zhenhua Liao,Xiaohong Mu,Lin Xu,Dingding Xiang,Yuhong Liu

doi:10.3390/polym9110589

Abstract

Titanium (Ti) and its alloys are widely used in biomedical devices. As biomaterials, the blood compatibility of Ti and its alloys is important and needs to be further improved to provide better functionality. In this work, we studied the suitability of zirconia (ZrO2) particle reinforced poly-ether-ether-ketone (PEEK) coatings on Ti6Al4V substrates for blood-contacting implants. The wettability, surface roughness and elastic modulus of the coatings were examined. Blood compatibility tests were conducted by erythrocytes observation, hemolysis assay and clotting time of recalcified human plasma, to find out correlations between the microstructure of the ZrO2-filled PEEK composite coatings and their blood compatibilities. The results suggested that adding ZrO2 nanoparticles increased the surface roughness and improved the wettability and Derjaguin-Muller-Toporov (DMT) elastic modulus of PEEK coating. The PEEK composite matrix coated Ti6Al4V specimens did not cause any aggregation of erythrocytes, showing morphological normal shapes. The hemolysis rate (HR) values of the tested specimens were much less than 5% according to ISO 10993-4 standard. The values of plasma recalcification time (PRT) of the tested specimens varied with the increasing amount of ZrO2 nanoparticles. Based on the results obtained, 10 wt % ZrO2 particle reinforced PEEK coating has demonstrated an optimum blood compatibility, and can be considered as a candidate to improve the performance of existing PEEK based coatings on titanium substrates.

Highlights

Titanium (Ti) and its alloys have been widely used in blood-contacting medical devices, such as vascular stents, dental implants and artificial joints, owing to their excellent biocompatibility, CT/MRI compatibility and mechanical properties [1,2]
The surface roughness values (Ra) were measured by a 3D white-light interfering profilometer and the elastic modulus of the deposited coatings were determined by AFM
The variations of the surface roughness and elastic modulus of the PEEK based coatings are displayed in Figure 1, which can be regarded as the composites as a function of the ZrO2 particle content in wt %

Summary

Introduction

Titanium (Ti) and its alloys have been widely used in blood-contacting medical devices, such as vascular stents, dental implants and artificial joints, owing to their excellent biocompatibility, CT/MRI compatibility and mechanical properties [1,2]. It is reported that titanium is much more thrombogenic than other conventional biomaterials such as stainless steel [4]. Poor tribological behavior of titanium alloys limits its long-term service as an implant device [5]. Various biocoatings, such as hydroxyapatite (HA) [6], diamond-like carbon (DLC) [7], titanium nitrides (TiN) [8] and some polymeric coatings [9,10], have been developed to improve the tribological characteristics and hemocompatibility of Ti and. Each coating has its advantages and limits.

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Discussion

Conclusion