Construction and in vitro characterization of an optimized porosity-enabled amalgamated matrix for sustained transbuccal drug delivery

This research focused on constructing and characterizing an optimized porosity-enabled amalgamated matrix (P-EAM) for sustained transbuccal drug delivery. An interphase, co-particulate, co-solvent, homogenization technique and lyophilization guided through a Box-Behnken experimental design was employed in the fabrication, characterization and optimization of 15 P-EAMs. The effects of varying factor levels on the characteristic in vitro physicochemical performances of the P-EAMs were explored. Formulations had an average weight of 128.44 +/- 3.48 mg with a dimensional size of 8 mm by 5 mm. Surface morphology showed varieties of pore structures, widespread distributions and uneven inter-connectors. Satisfactory drug-loading was achieved (53.14 +/- 2.19-99.02 +/- 0.74%). Overall amount of drug released in 8 h was measured by the MDT50% value which ranged between 22.50 and 225.00 min. Formulation demonstrated significant levels of ex vivo bioadhesive strength measured as detachment force (F-det = 0.964 +/- 0.015 to 1.042 +/- 0.025 N) and work of adhesion (omega(adh) = 0.0014 +/- 0.00005 to 0.0028 +/- 0.00008J). The potential of the P-EAMs to initiate and sustain ex vivo transbuccal permeation of drug was shown and measured as a cumulative value of between 25.02 +/- 0.85 and 82.21 +/- 0.57% in 8 h. Formulations were mesoporous in nature with pore sizes ranging from 40 to 100 angstrom characterized by the presence of interconnectors. Statistical constraints were simultaneously set to obtain levels of independent variables that optimized the P-EAM formulation. (C) 2010 Elsevier B.V. All rights reserved.