Microwave assisted aloe vera coating on metallocen polyethylene for improving biocompatibility

Abstract

Metallocene polyethylene (mPE) is known for its commendable physical and mechanical properties, but the problem of hemocompatibility hampers its clinical application. Therefore, an Aloe vera (AV) extract was coated on mPE assisted by microwave to rectify this problem. Initially, the duration of microwave treatment was optimized to 60 s by considering the weight degradation of the samples. Similarly, the coating time of fibrous AV extract was optimized to 12 h (A-12 h-mPE) and 24 h (A- 24 h-mPE) based on wettability increment. Fourier transform infrared (FTIR) spectra showed the addition of OH- groups and the vibration characteristic of several active constituents available in the AV coating. The decrease in mean contact angle of pristine mPE (P-mPE) from 88.43° to 32.93° in the A-24 h-mPE sample, depicts an increase in the wettability. Meanwhile, scanning electron microscopy (SEM) images displayed the presence of AV extract. The influence of microwave in enhancing the coating characteristics was investigated through Hirox 3D images, peel test, and degradation studies. In addition, an improvement in average surface roughness (Ra) of P-mPE from 2.069 nm to 7.796 nm for the A-24 h-mPE was interpreted through atomic force microscopy (AFM) analysis. Finally, the in vitro coagulation studies indicated a reasonable delay in blood clotting time on the AV coated mPE samples, which was presented by activated partial thromboplastin time (170 s) and prothrombin time (39 s) assay. The coated mPE samples also reduced hemolysis and platelet adhesion insinuating the potential usage of AV coated mPE in permanent and temporary blood contacting devices.