Membranas do tipo fibras ocas de poli(éter imida) para aplicação em hemodiálise

Abstract

Hemodialysis is the most commonly used treatment for chronic kidney disease. Although consolidated, it still presents some limitations, such as the low removal of medium sized molecules and the low biocompatibility of the membranes used during the procedure. Therefore, this study aims at the synthesis and characterization of hemocompatible hollow fiber membranes to application in hemodialysis. The effects of operational variables and synthesis conditions on the production of hollow fibers of polyetherimide and polyvinylpyrrolidone (PEI/PVP) were evaluated and their surface modification was carried out through the covalent attachment of heparin. Transport properties of functionalized hollow fibers were comparable to commercial high flux dialysers, presenting hydraulic permeability of 63,8 L/h.m².bar, with better removal of medium molecular weight solutes. The surface modification resulted in more hydrophilic membranes (contact angle reduced from 76.5° to 58.5°), reducing the occurrence of protein adsorption by more than 50%; in contact with blood, these membranes reduced the occurrence of platelet adhesion, increased APTT from 34 s to 46 s, and did not lead to the complement system activation. These results indicate that the modified membranes have antithrombogenic and biocompatibility characteristics, which are desired for materials of the hemodialysis filters.