Strong Antibacterial Fibers From Lysozyme and Single Walled Carbon Nanotubes

V.A. Davis, D.W. Horn, G. Ao, M. Maugey, C. Zakri, P. Poulin
Auburn Unviersity, US

Keywords: nanotube, SWNT, lysozyme, antibacterial, fiber

Summary:

Dry spinning stabilized aqueous dispersions of single-walled carbon nanotubes (SWNT) and lysozyme (LSZ) can result in high strength antibacterial fibers. LSZ is a naturally abundant antibacterial enzyme, which can be found in chicken egg white. The retention of LSZ’s natural antibacterial activity during dispersion with SWNT, has enabled the manufacture of coatings and fibers that combine the properties of SWNT with the antibacterial properties of LSZ. Fibers are of particular interest for biomedical applications such as fabrics, dressings, clothing, and medical devices. Research has shown that LSZ’s tryptophan residue has sufficiently favorable interactions with SWNT to enable dispersion of individuals at low concentration. However, at higher concentrations depletion effects result in large SWNT aggregates. The addition of the cationic surfactant TTAB enabled an order of magnitude higher concentration and stable spinning dispersions. The dispersions were combined with an aqueous polyvinyl alcohol (PVA) solution and dry spun into fibers. The fibers’ mechanical properties were strongly influenced by the initial dispersion state. The most robust fibers were dry spun from LSZ-TTAB-SWNT supernatants that were combined with the PVA solution; they had four times the toughness of spider silk and 70% of the native LSZ activity.