A Rapid Shear-induced Method for the Preparation of Chitosan Gel

Technology: Method for the preparation of chitosan

Industry: Pharmaceutical Waste-water treatment; Applications: Water Treatment;

Market: The global Chitosan market is projected to reach at a CAGR of 20.1% during (2023-2030).

Chitin is an amino polysaccharide, which is extracted from the exoskeleton of crustaceans such as crabs, prawns, lobsters & from the cell-wall of few fungi & chitosan solution has been used to flocculate or coagulate negatively-charged organic/inorganic impurities from wastewater, due to its polycationic nature.
The gelation of chitosan has been done using two techniques; crosslinking & copolymerization. However, those techniques are not able to produce gel due to using non-biodegradable grafts.
A few prior arts method discussed herein which lack mechanical stability & susceptible to change in pH, temperature, ionic strength.
Hence, it is needed to address above issues.

Present patent claimed a rapid shear induced method of forming chitosan gels using ionotropic gelation technique.(Refer Fig.1)

Said method comprises the steps of:

First Step describes about preparing a chitosan solution by dissolving chitosan in a mildly acidic aqueous solution;
Second step describes about forming a mixture by adding a water-soluble metal salt to said chitosan solution;
Third step describes about adding a solution of a water-soluble phosphate salt or Phosphoric acid, to said mixture of water soluble metal
salts and said chitosan solution; and
Fourth step describes about shaking said mixture of said water-soluble metal salt, the water-soluble phosphate salt & the chitosan solution to generate metal phosphates, in situ, & form the chitosan gels, without post processing or neutralization step.

Technical Perspective

Proposed chitosan gelation is produced either by shaking the mixture for a particular duration of ten seconds, or by longer storage of the mixture.
Said mildly acidic aqueous solution is selected among the group of acetic acid, hydrochloric acid, nitric acid, formic acid and trifluoroacetic acid, wherein the pH level of mildly acidic aqueous solution <6.5.

Industrial Perspective:

Bridgeable cost-effective method having features as mechanical stability, other parameters(pH, temperature & ionic strength.
Applicable Biotechnology & environmental applications

Prof. Dhamodharan R

Department of Chemistry

TRL-3

Proof of Concept & validated

Technology Transfer