Preparing Chito-Oligosaccharides as Antimicrobial Agents for Cotton

Abstract

Cotton fabric with good antimicrobial activity and durability to washing is obtained by using chito-oligosaccharides without the need for a binding chemical as a crosslinker. The fully deacetylated chitosan is depolymerized into chito-oligosaccharide using sodium nitrite. The average degree of polymerization (DP) of chito-oligosaccharide is determined by color imetric titration of a terminal aldehyde group of chito-oligosaccharide. In a pad-dry-cure process, two different chito-oligosaccharides (DP = 3 and 10) are applied to cotton fabric using the chemical reactivity of the terminal aldehyde group. The antimicrobial activity and durability to washing of the treated cotton are evaluated. The results show that at the fiftieth wash cycle, the cotton fabrics treated with 2.4% chito-oligosaccharide are able to maintain 95% (for a DP of 3) and 100% (for a DP of 10) bacterial reductions.