I searched for a method to purify chitosan and found out one from a research paper.
- first chitosan is dissolved in Acetic acid.
- then it is re-precipitated by 10% NaOH.
- Finally washed with distilled water until neutral and freeze dried.
After this treatment, molecular weight of purified chitosan was higher than that of the original chitosan.
Is molecular weight changing whilst dissolving in acetic acid?
Thank you in advance...