Oligochitosan/Chitosan Oligosaccharides (COS) is one of Chitosan derivatives produced by the further hydrolysis of Chitosan resulting in a shorter chain length.

COS has a lower molecular weight (Mw), high degree of deacetylation (DD), and higher degree of polymerization (DP), thus being less viscous and completely water soluble.

With excellent absorption abilities at neutral pH, COS is a highly effective and anti-microbial bioactive material.