Development and Evaluation of Mucoadhesive Buccal Tablet of Simvastatin

Mucoadhesive buccal tablets of Simvastatin were prepared with an objective of enhanced bioavailability using Carbopol 934P in varying concentration with secondary polymers like Sodium alginate, Sodium CMC, HPMC K4M, Xanthan gum by direct compression method. Preformulation studies confirmed identity and purity of the drug by means of IR Spectroscopy and Melting point determination. An analytical method was developed for Simvastatin. The tablets were evaluated for hardness, thickness, weight variation, friability and drug content concluded that all these parameters were in acceptable range of pharmacopoeial specification. The tablets were studied for surface pH, swelling index, in vitro drug release, ex vivo residence time, mucoadhesive strength, ex vivo permeation. The surface pH of the tablet was from 6.16 to 6.66 which fall in the range of salivary pH and all the tablets showed ex vivo residence time of 3.24 to 6.35 h indicated good adhesive capacity of tablet. The buccal tablet showed good swelling of >65% up to 8 h maintaining the integrity of polymers. The in vitro release of simvastatin was extended only for 6–7 h, if Carbopol 934P in combination with secondary polymer Xanthan gum was used. While the tablets contained Carbopol 934P along with Sodium alginate, Sodium CMC, HPMC K4M prolonged the released up to 8 h. Hence Carbopol 934P along with sodium alginate, Sodium CMC, HPMC K4M could be used to prepared prolonged released buccal tablet. The in vitro release of batches containing Carbopol 934P with sodium CMC show maximum drug release 97.11% which obeyed Korsemeyer-Peppas release kinetics with Non fickian transport mechanism of release due to more hydrophilic nature of polymer and drug. All the tablets showed good mucoadhesive strength of 7.60 to 30.10 g with high force of adhesion. The ex vivo permeation concluded that Carbopol enhanced the flux and permeability coefficient of simvastatin from the tablets. More flux observed in batches containing Carbopol 934P with Sodium CMC.