Unravelling the potential of nitric acid as a surface modifier for improving the hemocompatibility of metallocene polyethylene for blood contacting devices

Muthu Vignesh Vellayappan; Saravana Kumar Jaganathan; Ida Idayu Muhamad

doi:10.7717/peerj.1388

Unravelling the potential of nitric acid as a surface modifier for improving the hemocompatibility of metallocene polyethylene for blood contacting devices

PeerJ. 2016 Jan 19:4:e1388. doi: 10.7717/peerj.1388. eCollection 2016.

Authors

Muthu Vignesh Vellayappan¹, Saravana Kumar Jaganathan¹, Ida Idayu Muhamad¹

Affiliation

¹ IJN-UTM Cardiovascular Engineering Centre, Faculty of Biosciences and Medical Engineering, Universiti Teknologi Malaysia , Malaysia.

Abstract

Design of blood compatible surfaces is obligatory to minimize platelet surface interactions and improve the thromboresistance of foreign surfaces when they are utilized as biomaterials particularly for blood contacting devices. Pure metallocene polyethylene (mPE) and nitric acid (HNO3) treated mPE antithrombogenicity and hydrophilicity were investigated. The contact angle of the mPE treated with HNO3 decreased. Surface of mPE and HNO3 treated mPE investigated with FTIR revealed no major changes in its functional groups. 3D Hirox digital microscopy, SEM and AFM images show increased porosity and surface roughness. Blood coagulation assays prothrombin time (PT) and activated partial thromboplastin time (APTT) were delayed significantly (P < 0.05) for HNO3 treated mPE. Hemolysis assay and platelet adhesion of the treated surface resulted in the lysis of red blood cells and platelet adherence, respectively indicating improved hemocompatibility of HNO3 treated mPE. To determine that HNO3 does not deteriorate elastic modulus of mPE, the elastic modulus of mPE and HNO3 treated mPE was compared and the result shows no significant difference. Hence, the overall observation suggests that the novel HNO3 treated mPE may hold great promises to be exploited for blood contacting devices like grafts, catheters, and etc.

Keywords: Blood contacting device; Hemocompatibility; Nitric acid; Surface modification.

Grants and funding

This work was supported partly by GUP Universiti Teknologi Malaysia with the Grant Vot No:Q.J130000.2509.10H13. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.