Fabrication of carbon nanotube nanocomposites via layer-by-layer assembly and evaluation in biomedical application

Aim: To investigate the influence of ion pairing of carboxylated multiwalled carbon nanotubes (MWCNT-COOH) and polycations on the layer-by-layer assembly of nanocomposites and their biocompatibility for biomedical applications. Materials & methods: Strong polycation poly(dimethyldiallylammonium chloride), and weak polycations chitosan and polyethyleneimine were selected to assembly with MWCNT-COOH. The MWCNT-COOH/polycation nanocomposites were analyzed by their physicochemical, electrical properties and biocompatibility. Results: The ion pairing of CNTs/polyelectrocytes played a critical role in the layer-by-layer assembly. Strong interactions between MWCNTs and poly(dimethyldiallylammonium chloride) produced thicker nanocomposites with rougher surfaces, higher MWCNT mass and better conductance. All the MWCNT multilayered nanocomposites were of good biocompatibility. Conclusion: The MWCNT multilayered nanocomposites hold high potential for biomedical applications.