Formulation and In-Vitro Evaluation of Mucoadhesive Diltiazem Hydrochloride Buccal Tablets


Mucoadhesive tablets for buccal administration of diltiazemhydrochloride were prepared as an alternative to available diltiazem HCl dosageforms. Two types of tablets were developed each containing two mucoadhesivecomponents (hydroxypropylmethyl cellulose HPMC and sodium alginate) and(HPMC and carbopol) for each types, batches were produced by changingquantity of polymer. The formulations were tested for mucoadhesiveperformance and release pattern. In vitro bioadhesive strength studies showedthat the HPMC/carbopol formulations were more bioadhesive and less drugrelease rate compared with HPMC/alginate formulations. Increasing the contentof HPMC in HPMC/alginate tablets resulted in increase in detachment forcesand swelling index but lower release rates were observed. The release behaviorof all formulations was non-Fickian mechanism controlled by a combination ofdiffusion and chain relaxation mechanisms and best fitted zero-order kinetics.The buccoadhesive diltiazem HCl tablets containing 18.75% sodium alginateand 37.5% HPMC showed suitable release kinetics (n = 0.86, K0 zero orderrelease = 10.29 mg/h, MDT = 4.8 h) , good adhesive properties and did not showany interaction between polymers and drug based on FT-IR study.