Objective: Transmucosal buccal drug delivery could be an alternative for oral administration for systemic delivery of Verapamil Hydrochloride (VH), as it has low bioavailability 20 - 35 % due to its extensive first pass metabolism and variable absorption at GIT. Method: Buccal patches of VH were prepared by solvent casting method using bioadhesive polymers HPMC K4M, Carbopol 934P, Chitosan acetate and Okra mucilage isolated from Hibiscus esculantus fruits, in various combinations as per 24 half factorial model. The prepared medicated patches were subjected for in vitro and ex vivo characterization. Results: The mass uniformity, thickness, drug content, surface pH and folding endurance for the medicated patches were found satisfactory. The formulation contains Chitosan acetate and Okra mucilage has moderate swelling 38.86 % w/w in 2h, ex vivo mucoadhesion strength 27.78 ± 0.12 g on porcine buccal membrane and sustained in vitro release rate as 73.14 % (F7) compared to 93.06 % (F1) in 120 min with non-Fickian mechanism. The flux value of F1 (0.635 mg/cm2/h) was modified to the range of 0.538 mg/cm2/h to 0.294 mg/cm2/h by addition of Chitosan acetate and Okra mucilage in combination with HPMC K4M and Carbopol 934P. No significant changes were observed in the Physical and chemical characteristics during short term stability study. Chemical compatibility of VH with polymers was confirmed by FTIR spectroscopy. Conclusion: Overall, Chitosan acetate and Okra mucilage imparts good physical properties to the buccal patch, significantly controls release and diffusion of VH from the matrix film with satisfactory bucco-adhesion.
Key words: Buccal Patches, Mucoadhesive, Transmucosal, Verapamil HCl, Okra Mucilage, Chitosan Acetate.