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Specialty Chemistry Forums => Other Sciences Question Forum => Topic started by: gumusonur on August 03, 2018, 04:26:06 AM

Title: CHITOSAN
Post by: gumusonur on August 03, 2018, 04:26:06 AM

hi,

How can i solve ''Chitosan''?
anybody know?

thanks

Title: Re: CHITOSAN
Post by: P on August 03, 2018, 04:35:52 AM

Do you mean 'dissolve'? Or is there a problem to 'solve' with your batch of it.

I had to look up what it was   -  a sugary powder obtained from shrimp and crab shells? Wiki suggests they dissolve it with alkaline solutions. I have never done it. Sounds like sodium hydroxide will do it from the wiki page about it.

Title: Re: CHITOSAN
Post by: gumusonur on August 03, 2018, 04:54:17 AM

i read that we can solve chitosan in acetic acid but Sodium hydroxide is solution alkaline. despite the fact that i will try this method.

Title: Re: CHITOSAN
Post by: wildfyr on August 03, 2018, 09:28:36 AM

P I don't know where you got that info but, you use acidic solution. It protonates the amine to help solubility. Chitosan is made from Chitin by boiling it in caustic to deactylate the amine

Title: Re: CHITOSAN
Post by: gumusonur on August 03, 2018, 09:49:36 AM

wildfyr, which one should I use? asidic or basic solution?
i have very little chitosan. I have to use it carefully. :)
P and Wildfyr, also, i wanna many thanks to you for your interest..

Title: Re: CHITOSAN
Post by: wildfyr on August 03, 2018, 11:22:23 AM

Acid. I am absolutely sure. It is soluble below pH 4 I believe.

Title: Re: CHITOSAN
Post by: P on August 06, 2018, 04:42:37 AM

Quote from: wildfyr on August 03, 2018, 09:28:36 AM

P I don't know where you got that info but, you use acidic solution.

I'll bow to your better knowledge of it - As O said, I had to look it up because I didn't know what it was. The wiki page said sodium hydroxide - maybe that's the pre treatment to help solubility:

"Chitosan /ˈkaɪtəsæn/ is a linear polysaccharide composed of randomly distributed β-(1→4)-linked D-glucosamine (deacetylated unit) and N-acetyl-D-glucosamine (acetylated unit). It is made by treating the chitin shells of shrimp and other crustaceans with an alkaline substance, like sodium hydroxide." - https://en.wikipedia.org/wiki/Chitosan

Title: Re: CHITOSAN
Post by: wildfyr on August 06, 2018, 08:25:11 PM

Yep, you do a heterogenous reaction of chitin with caustic, then filter and rinse with water. As I said before, this deactylates the amide. The resulting amine cns be protonated to give a water soluble polymer with a lot of nifty properties.

Title: Re: CHITOSAN
Post by: gumusonur on August 07, 2018, 09:02:47 AM

hey, 1.5% Chitosan dissolved in 1% acetic acid and %1 lactic acid solution. thanks everything.