Synergistic effect of carbon nanotubes and graphene for high performance cellulose acetate membranes in biomedical applications.

Comparative evaluation of innovative combinations of three types of carbon nanomaterial (CNM) highlighted membranes with important potential for biomedical applications. Non-solvent induced phase separation coupled with ultrasound technique was used to generate membranes comprised of (i) cellulose acetate/ammonia functionalized carbon nanotubes (CA/CNT), (ii) cellulose acetate/ammonia functionalized graphene oxide (CA/GO), and (iii) cellulose acetate/CNT-GO. Structural, topographical and thermal features as well as water and ethanol permeation, bovine serum albumin (BSA) and haemoglobin (Hb) rejection were evaluated. Biocompatibility in terms of cytotoxicity, cell proliferation and adhesion were explored using a 3T3E1 cell line. The formation of amorphous structures, within which the CNMs were well dispersed, facilitated the development of smoother topographies. Addition of CNMs generated morphological changes influencing a decrease in water and ethanol fluxes. Furthermore, CNMs concentrated within the membrane skin layer exhibited repellent effects against BSA and Hb molecules and excellent cytocompatibility.