Propranolol hydrochloride release behaviour of crosslinked chitosan membranes.

Chitosan membranes of 20 microns thickness were prepared by a solvent evaporation technique and crosslinked with different concentrations of glutaraldehyde to obtain membranes of various degrees of crosslinking. These membranes were characterized by thermogravimetric (TG) analysis, differential scanning calorimetry (DSC) and tensile strength studies. The effect of crosslinking on the permeability of membranes to propranolol hydrochloride was evaluated by permeation studies conducted in static glass diffusion cells. A decrease in the thermal stability of chitosan membranes due to crosslinking was observed. The tensile strength of the membranes was improved by crosslinking. The introduction of crosslink points within the membrane reduced its permeability to propranolol hydrochloride as evidenced by decreased permeability and diffusion coefficients. Permeability studies revealed the operation of a pore mechanism in the transport of hydrophilic agents such as propranolol hydrochloride through chitosan and crosslinked chitosan membranes.