Formulation Development of Antihypertensive Buccal Patches and Characterisation

Abstract

Buccal patches containing atenolol and nifedipine were fabricated from mucoadhesive polymers like chitosan and hydroxypropyl methylcellulose (HPMC) 15CPS for the purpose of prolonging drug release and improving their bioavailability. The fabricated films were smooth, uniform and the colour was brown with good flexibility. The weight and thickness of all the formulations were found to be uniform. The drug content was in the range of 95–98%, indicating drug uniformity. Swelling index increased with increased content of HPMC, highest swelling index of 0.7935 was shown by formulation FA3. Bioadhesive force, tensile strength, percentage elongation and mucoadhesion time increased with the increase in HPMC concentration. In vitro drug release showed controlled rate of drug release for formulations with higher concentration of HPMC such as FA3 which released of 97.16% of atenolol and 96.96% nifedipine in 5.5 h. The drug release from the patches followed Korsmeyer Peppas model except for the formulations FA1 which followed first order model. Ex vivo permeation studies through porcine mucosa showed maximum permeation of 96.32 and 95.12% for atenolol and nifedipine, respectively from FA3 in 6 h. In vivo in rabbits demonstrated prolonged drug absorption from the buccal patch FA3 and the  both drugs from the formulation FA3 greater than that of oral solution indicating enhanced bioavailability via buccal route. In vitro in vivo correlation was obtained in the range of 0.9413–0.9724. Satisfactory ex vivo in vivo correlation was obtained for both the drugs in the range of 0.9729–9802. 

Keywords:  Buccal, atenolol, nifedipine, chitosan, HPMC