Dear Liker,

In order for chitosan to be dissolved in 0.1 M HCl, you have to heat at 60 C while stirring for 5-6 hours. If you prefer not to heat, you should stir the mixture for 12 hours. In some cases sonication might be efficient than stirring.

Hoping this will be helpful,

Rafik

Chitosan has a positive charge from the glucosamine groups. The aggregates you see may be caused by coacervation of the protein with the chitosan caused by ionic interactions. Two possible ways to eliminate this effect would be to change the pH and to add salt.

Use surfactants , in ppm