چکیده (انگلیسی):

The experimental work of studying
the adsorption of ketotifen and allopurinol by chitosan
focused on determining the solubilities and the
adsorption isotherms of the adsorbates employed in
this study. The adsorption of the aforementioned
compounds by chitosan was studied using the rotating
bottle method. The concentrations, both before and
after the attainment of equilibrium, were determined
with the aid of a reversed-phase high-performance
liquid chromatography column. The results of these
studies demonstrated that ketotifen and allopurinol are
both adsorbed by chitosan. The nonlinear Langmuirlike
and the Freundlich models both were applied to
the experimental data. The correlation coefficients
obtained from the nonlinear Langmuir-like model
were better than those obtained from Freundlich
model, suggesting that allopurinol and ketotifen
interacted with certain specific binding sites on the
chitosan surface. The allopurinol adsorption
experiments indicated that the particle size of chitosan
and therefore the surface area can significantly affect
the Langmuir capacity constant, while the affinity
constants are statistically the same. As expected from
the solubility studies, the ketotifen adsorption
experiments at 2 different pHs (7 and 10) showed that
the adsorption affinity at pH 10 was much higher than
at pH 7. What was not expected was that the capacity
constants were significantly different, suggesting that
further studies are needed using common ion buffers
and multicomponent adsorption for the proper
mechanism to be determined.