Development of antimicrobial composite films of chitin nanofiber reinforced chitosan containing silver salt / Tang Chee Kuang

• Main Author: Tang, Chee Kuang
• Format: Thesis
• Published: 2017
• Subjects: T Technology (General)
• Online Access: http://studentsrepo.um.edu.my/8553/4/KGA100021_THESIS.pdf; http://studentsrepo.um.edu.my/8553/

Pure chitosan films have poor tensile strength and elasticity. Hence development of high strength composites that is biocompatible for biomedical applications are desired. In this work, 16.7 wt. % of chitin nanofiber, extracted using acid hydrolysis process was incorporated into chitosan polymer matrix to improve the tensile strength and elasticity of the composite films. Composite films were prepared from chitosan by solution casting after incorporating chitin nanofibers as nanofillers and different types of silver salt as antimicrobial agent. Silver sulfate, Ag2SO4 and silver acetate, AgC2H3O2 with various amounts of 0.1, 0.3, 0.5 and 0.7 g were doped into the polymer matrix to improve the antimicrobial properties of the composite films. Results show that the tensile strength of the chitosan films can be increased by incorporating chitin nanofibers and silver sulfate up to a certain amount without appreciable change in the chemical structure of the chitosan films. The addition of 0.1 g of silver sulfate could improve greatly the tensile strength of neat chitin-chitosan composite while providing improved antimicrobial properties. The antimicrobial efficacy of the composite films was proven using the Kirby-Bauer disk diffusion susceptibility test with Escherichia coli. Silver ion release test demonstrates that the amount of silver salt incorporated into the composites could produce sufficient silver ion for enhancing antimicrobial capability. Overall results suggested that chitin nanofiber-chitosan doped with 0.1 g silver sulfate have a potential for application where antimicrobial characteristics is needed such as wound healing dressings, food packaging industries or coatings for medical devices.