Investigations have been carried out to elucidate the influence of the decision parameters
on the particle size of chitosan microspheres intended as support for immobilized
enzymes. The chitosan particles were prepared by w/o emulsion crosslinking method
by dispersing the aqueous chitosan solution in an oil phase composed of 40 v/v% paraffin
oil and 60 v/v% n-octane in the presence of Tween 80 surfactant agent. After emulsification
the droplets were hardened by glutaraldehyde crosslinking agent resulting in spherical
microparticles. During a series of experiments the speed of stirring applied for emulsification,
the concentration of the chitosan, the relative amounts of the surfactant and the
glutaraldehyde were varied according to a plan obtained by four factorial three levels
experimental design. The depending variable was the mean size of the chitosan microspheres.
After evaluating the result of the experiments it was found that the concentration
of chitosan, the relative amounts of the surfactant and crosslinking agents had significant
influence on the particle size, while surprisingly the stirring rate had only non
significant, minor effect.