How about adding surfactant like tween20? I previously sustained PS micron sphere by adding tween 20 to the aqueous phase

They should dissolve at acidic pH

Hi,

To resuspend chitosan-TPP nanoparticles after isolation by centrifugation, it is necessary to first pipette a small glycerol bed (ca. 20 µL) at the bottom of the vial and carefully add on top of it the nanoparticles suspension (without mixing with the glycerol). After centrifugation (typically 10k x g, 40 min), the supernatant must be removed carefully and the nanoparticles pellet will be deposited at the glycerol phase. They can be resuspended by adding new solvent and by vigorous mixing in the pipette tip and vial. I hope that this is helpful.

I had the same problem ... I tried Ethanol, Methanol, Acetic Acid, Distilled Water, Toluene, Tetrahydrofuran, Hexane, Cyclohexane, Acetone, Ethyl Acetate, DMSO Methylene Chloride, Propanol Chloroform, Petroleum Ether. I suppose that the technique that I used for the crosslinking of the chitosan, caused the formation of strong bonds that hinder the solubility. You could deal with HCl and / or heat.

Highly recommended glycerol bed technique

Francisco or Sajit, do any of you have a published protocol that I can use for my encapsulations?

Thanks for all

It all about the methology applied, it is necessary to control the pH value for all the stages in order to prevent the strong bonds that sir Daniel Castañeda mentioned. Dr Francisco M Goycoolea gave an awesome explanation.

Have you already tested using an HCl solution (1N or greater) under agitation/shear?

In fact, the interactions between TPP and CHT are quite stable. Therefore, the combination of a potent chitosan protonator, combined with the use of intense energy input, such as a shear force, can help.

Generally nanoparticles not soluble. You can suspend it using sonicator. Regarding chitosan try to use 1% acetic acid.

2% acetic acid solution or 0.1% HCl solution

Chitosan Nanoparticles dissolve in acidic media, and chitosan dissolve in D.W. For dissolving of nano-chitosan it can added to solution of 1% acetic acid.

Try to use acetic acid