Enhancing antibacterial property: tetraethyl orthosilicate influence on quaternised chitosan/PVA film / Mohd Akasyah Sulaiman and Norin Zamiah Kassim Shaari

As a food packaging material, a biofilm barricades the food from contaminants. A film formulated from biopolymers with antibacterial properties is useful and holds high potential as a food packaging alternative since biopolymers are degradable, compostable, and made from renewable resources. Chitosan has been reported to demonstrate antimicrobial properties which are efficient against gram-positive and gram-negative bacteria. However, in its pure form, chitosan has poor solubility in most solvents and is limited to acidic environments only. Thus, in this study, chitosan was quaternised using hexadecyl trimethyl ammonium bromide to enhance its hydrophilicity and its antibacterial effectiveness. A film was formulated with a blend of quaternised chitosan with polyvinyl alcohol and tetraethyl orthosilicate. The FTIR results revealed the presence of peaks around 1400 cm-1 representing the asymmetric bending of the trimethylammonium group and 950 cm-1 corresponding to the quaternary ammonium group which show the success of the quaternisation process and the crosslinking with tetraethyl orthosilicate (TEOS) results in improving the hydrophilicity of the film. By using the technique of diffusion on the disc examined against E. coli, it was observed that all formulated films regardless of the presence of TEOS have antibacterial properties. The fabricated films can be used as food packaging alternative materials.