Influence of crosslinking process conditions on molecular and supermolecular structure of chitosan hydrogel membrane

Unmodified (Ch) and ionically crosslinked with sodium tripolyphosphate (Ch/TPP) chitosan membranes were prepared. Various crosslinking conditions (pH, crosslinking time) were applied. Differences in membrane molecular structure was examined using FTIR spectroscopy. Scanning electron microscopy (SEM) coupled with Energy Dispersive X-Ray (EDX) Spectrometer as well as atomic force microscopy (AFM) were used for estimation of an effect of crosslinking conditions on supermolecular structure of chitosan membrane. Strong effect of pH of crosslinking TPP solution on crosslinking agent distribution inside the membranes and roughness of membrane surface was found. Differences in membrane morphology prior and after crosslinking results from differences in crosslinking density.