Buccal mucoadhesive tablets of flurbiprofen: Characterization and optimization

The aim of this work was to develop and optimize sustained-release mucoadhesive tablets of flurbiprofen. Mucoadhesive polymers used were chitosan as primary polymer and hydroxypropylmethyl celluose, hydroxypropyl cellulose, or sodium carboxymethyl cellulose as secondary polymer. Tablets were evaluated in terms of weight variation, thickness, hardness, friability, swelling, surface pH, in vitro mucoadhesive force, and in vitro release. The compatibility between flurbiprofen and the tablet excipients was confirmed by fourier transfer infrared studies. Both the primary and secondary polymers were found to have synergistic effects on tablet swelling, bioadhesion, and in vitro drug release. Formulations containing sodium carboxymethyl cellulose (F(1)) showed a maximum swelling index of 4.144 after 8 h, maximum mucoadhesive force (0.27 N), and convenient in vitro release over 8 h. D-optimal design was employed to evaluate the effect of the ratio of the primary polymer (X(1)) and the type of secondary polymer (X(2)) on the swelling index after 8 h (Y(1)), drug release after 8 h (Y(2)) and time taken for 30% drug release (Y(3)).