Abstract
The main objective of the paper was to prepare eco-friendly chiral hydrogels from chitosan and betulinic aldehyde under ultrasonic radiation effect, targeting their use for enantiomeric separations. This strategy promoted the obtaining of the hydrogels by supramoleclar organization of the imine units bonding the betuline skeleton with chitosan into ordered clusteres, while not altering the physico-chemical properties of the reagents. FTIR, SEM, CD spectroscopy and POM techniques were used to prove the pelicularities of the hydrogelation mechanism under the ultrasonication. The stability of the hydrogels was investigated by monitoring the influence of the swelling in three media of diferent pH, by POM and CD. It was concluded that the chiral hydrogels prepared by ultrasonication are stable when the pH vary from acidic to basic, indicating the new synthetic approach as a valuable method to yield suitable materials for enatiomeric separations in medical field.
Keywords: chitosan hydrogels; ultrasonication; betulinic aldehyde; chiroptical; enantiomeric filtration