ABSTRACT:
Mucoadhesive patch releasing the drug in the oral cavity at predetermined rate may present distinct advantages over traditional dosage forms such as tablets, gels and solutions. The present study was concerned with the preparation and evaluation of mucoadhesive buccal patches of nifedipine as it’s half life is 2hr and drug has high first pass metabolism. A buccal patch for systemic administration of nifedipine in the oral cavity has been developed using two different mucoadhesive polymers namely HPMC K4M and Carbapol 974. The developed patches were evaluated for the physicochemical, mechanical and drug release characteristics. The formulations were tested for Patch thickness, Surface pH, Folding endurance, Swelling index, Residence time, in vitro drug permeation studies, moisture absorption studies and in vitro bioadhesion studies. The patches showed good mechanical and physicochemical properties to withstand environment of oral cavity. The in-vitro release study showed that patches could deliver drug to the oral mucosa for a period of 8 hrs. The results indicate that suitable bioadhesive buccal patches with good permeability could be prepared. The formulation with HPMC K4M (2.5%) and Carbapol 974 (3.5%) shows 89.58% and 91.45% permeated through cellophane membrane in 8 hr. The physicochemical interactions between Nifedipine and polymers were investigated by Fourier transform infrared (FTIR) Spectroscopy. FTIR study shows no any evidence of an interaction with the polymers used and was present in an unchanged state.