Diffusional system based on tolazoline hydrochloride included in a reticulated carboxymethylcellulose hydrogel

This paper presents a diffusional system consisting of tolazoline hydrochloride included into a carboxymethylcellulose based hydrogel, showing a high swelling capacity in water. The process kinetics of the drug inclusion into hydrogel as well as of the drug releasing have been studied. The tolazoline hydrochloride release was performed by elution with a simulated biological fluid within the digestive tract, at the small intestine level (pH = 8.2) where the drug is mostly absorbed. The results make evident a zero-order kinetics over the 30-400 min range, which would place the system among those with 'sustained' release, with obvious advantages compared with the classical drug administration.