Evaluation of Plantago major L. seed mucilage as a rate controlling matrix for sustained release of propranolol hydrochloride

Polysaccharide mucilage derived from the seeds of Plantago major L. (family Plantaginaceae) was investigated for use in matrix formulations containing propranolol hydrochloride. HPMC K4M and tragacanth were used as standard for comparison. The hardness, tensile strength, and friability of tablets increased as the concentration of mucilage increased, indicating a good compactibility of the mucilage powders. The rate of release of propranolol hydrochloride from P. major mucilage matrices was mainly controlled by the drug/mucilage ratio. Formulations containing P. major mucilage were found to exhibit release rate comparable with HPMC containing matrices at a lower drug/polymer (drug/HPMC 2:1). These results demonstrated that P. major mucilage is a better release retardant compared to tragacanth at equivalent content. The results of kinetic analysis showed that in F3 (containing 1:2 drug/mucilage) the highest correlation coefficient was achieved with the zero order model. The swelling and erosion studies revealed that, as the proportion of mucilage in tablets was increased, there was a corresponding increase in percent swelling and a decrease in percent erosion of tablets. The DSC and FT-IR studies showed that no formation of complex between the drug and mucilage or changes in crystallinity of the drug was occurred