Polyelectrolyte Complexation of Chitosan and WS2 Nanotubes

Eimear Magee, Fengwei Xie, Stefano Farris, Andrea Dsouza, Chrystala Constantinidou, Alla Zak, Reshef Tenne, Tony McNally

Research output: Contribution to journalArticlepeer-review


The inclusion of tungsten disulphide nanotubes (WS2 NTs) in chitosan, plasticized with glycerol, facilitates the formation of a polyelectrolyte complex. The glycerol interrupts the intramolecular hydrogen bonding between chitosan chains allowing positively charged protonated amines of chitosan to form a complex with negatively charged oxygen ions chemisorbed to the tungsten atoms in defects. These interactions, with the unique mechanical and chemical properties of WS2 NTs, result in a chitosan film with superior properties relative to unfilled chitosan. Even at low WS2 NT loadings (≤1 wt%), the Young's modulus (E) increases by 59%, tensile strength (σ) by 40% and tensile toughness by 74%, compared to neat chitosan, without sacrificing ductility. Addition of highly dispersed WS2 NTs significantly improves the gas barrier properties of chitosan, with a 50% reduction in oxygen permeability, while the addition of both glycerol and WS2 NTs to chitosan effectively reduces the carbon dioxide permeability by 80% and the water vapor transmission rate by 90%. The intrinsic antimicrobial efficacy of chitosan against both Gram-positive and Gram-negative bacteria is enhanced on inclusion of WS2 NTs. Polyelectrolyte complexation of WS2 NTs and glycerol-plasticized chitosan provides a cost-effective, sustainable route to biodegradable films with desirable mechanical, gas barrier properties, and antimicrobial efficacy suitable for food packaging applications.

Original languageEnglish
Article number2300501
JournalAdvanced Materials Interfaces
Issue number6
Early online date17 Dec 2023
Publication statusPublished - 23 Feb 2024


  • antimicrobial efficacy
  • barrier properties
  • chitosan
  • composite
  • polyelectrolyte complex
  • WS nanotubes

ASJC Scopus subject areas

  • Mechanics of Materials
  • Mechanical Engineering

Cite this